JP2005221000A - Sealed hydraulic damper - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a sealed hydraulic damper having a metallic diaphragm with fully impermeability against oxygen, lubricant or the like and having satisfactory durability. <P>SOLUTION: The sealed hydraulic damper 1 is provided with a diaphragm 8 made of metal, and a first spring 8a and a second spring 8b having elasticity at both ends of the metallic diaphragm 8 by bending the metallic diaphragm 8. The first spring 8a is pushed into a first groove 2d by means of a crimping member 11, and the diaphragm 8, a housing 2, and a plunger 3 are so combined that the second spring 8b is pushed into a second groove 3e by means of a cap 4. <P>COPYRIGHT: (C)2005,JPO&NCIPI

Description

  The present invention relates to a sealed hydraulic damper used in an internal combustion engine.

  A sealed hydraulic damper is used as a silent mechanism or a gap adjusting mechanism in a valve operating apparatus of an internal combustion engine, which is as follows.

  In recent years, development of an electromagnetically driven valve operating device that opens and closes an intake valve and an exhaust valve using electromagnetic force has been underway. Such an electromagnetically driven valve operating device includes an armature made of a magnetic material that moves forward and backward in conjunction with an intake / exhaust valve, and a valve closing electromagnet that attracts the armature in the valve closing direction when an excitation current is applied. And a valve opening electromagnet that attracts the armature in the valve opening direction when an exciting current is applied.

  In such an electromagnetically driven valve device, the armature and the intake / exhaust valve stems are used to suppress the impact noise caused by the collision between the armature and the electromagnet and the collision between the intake / exhaust valve and the valve seat. A sealed hydraulic damper may be disposed between the ends.

  In this sealed hydraulic damper, a housing whose one end is an open end and the other end is closed, a plunger that is slidably inscribed in the housing, and a diaphragm that connects the housing and the plunger to cover the open end are provided. A configuration with which it is provided is known. In this configuration, a high-pressure chamber is formed between the plunger and the other end of the housing, and a reservoir chamber partially formed of a diaphragm is formed on the open end side of the housing. By filling the chamber with oil, a damping effect can be obtained with respect to the relative motion between the plunger and the housing by utilizing the viscous resistance of the oil moving between the high pressure chamber and the reservoir chamber (for example, Patent Document 1). reference.).

  In the above prior art, the diaphragm is often formed of rubber. In this case, since the diaphragm is highly permeable to gas and oil, oxygen and lubricating oil in the internal combustion engine permeate the diaphragm, and the reservoir chamber In some cases, the oil reacts with the oil sealed in the high-pressure chamber. In this case, the oil performance may be deteriorated, for example, the oil becomes highly viscous at a high temperature.

  On the other hand, attempts have been made to form the diaphragm with metal, but in this case, the durability of the metal diaphragm has become a problem. For example, in the vicinity of the joint portion between the metal diaphragm and the housing or the plunger, the metal diaphragm may cause metal fatigue and the sealing performance may deteriorate. Further, when the dimensions of the metal diaphragm change at high temperatures, excessive thermal stress may be applied to the diaphragm or the sealing performance may deteriorate.

Further, as a sealing method that can be used when the diaphragm and the housing or the plunger are coupled, there is a conventional technique in which the fixed end of the diaphragm is fixed with a disc spring and the sealing performance is improved by using the biasing force of the disc spring. However (see, for example, Patent Document 2), under the conditions in which the temperature change repeatedly occurs as in an internal combustion engine, there is a possibility that the pressing effect of the disc spring may be reduced due to thermal cycle fatigue. In addition, even under excessive vibration conditions, the elastic deformability of the disc spring may be reduced.
JP 2001-254609 A Japanese Patent Publication No. 3-3096 JP 2001-93841 A JP 2003-156155 A

  An object of the present invention is to provide a sealed hydraulic damper having a metal diaphragm having sufficient impermeability to oxygen and a lubricant and having sufficient durability.

  In the present invention for achieving the above object, the diaphragm in the hermetic hydraulic damper is made of metal, and an elastic spring portion is formed at the end of the metal diaphragm by bending the metal diaphragm. Form. And it makes the diaphragm, a housing, and a plunger couple | bond together by pressing the said spring part to the coupling | bond part in a housing and a plunger with a press member.

More specifically, a hollow housing in which one end is an open end and the other end is closed,
A plunger slidably inscribed in the housing;
A first coupling portion provided on a side surface of the housing and a diaphragm covering the open end of the housing by coupling with a second coupling portion provided on the open end side surface of the plunger;
A high-pressure chamber is formed by being surrounded by the inner surface on the other end side of the housing and the surface on the other end side of the plunger,
A reservoir chamber is formed by being surrounded by the surface of the open end side of the plunger and the diaphragm,
The high pressure chamber and the reservoir chamber are filled with oil,
A sealed hydraulic damper provided with a flow passage through which the oil flows between the high pressure chamber and the reservoir chamber,
The diaphragm is formed of a metal, and a spring portion formed by bending an end portion of the diaphragm is formed in a portion coupled to the first coupling portion and / or a portion coupled to the second coupling portion. Provided,
It further comprises a pressing member that presses the spring portion against the first coupling portion and / or the second coupling portion.

  Here, in the configuration including the housing, the plunger, and the diaphragm coupled to them, the diaphragm is deformed when the housing and the plunger move relative to each other. At that time, the diaphragm generally tries to deform uniformly. However, when the diaphragm and the housing or the plunger are coupled by a method such as welding or adhesion, a portion of the diaphragm that is coupled to the housing or the plunger is fixed without flexibility. Yes. Accordingly, in the diaphragm, the diaphragm cannot be uniformly deformed in the vicinity of the portion that is coupled to the housing or the plunger, and the amount of deformation in that portion is a place away from the portion that is coupled to the housing or the plunger. It becomes larger than the deformation amount. As a result, with relative movement of the housing and the plunger, an excessive load may be applied in the vicinity of the portion of the diaphragm that is coupled to the housing or the plunger.

Therefore, when the diaphragm is formed of metal, metal fatigue may occur in the vicinity of the portion coupled with the housing or the plunger, and the sealing performance of the diaphragm may be deteriorated. As a result, the durability of the sealed hydraulic damper is deteriorated. Moreover, at the time of high temperature, there exists a possibility that said metal fatigue may be accelerated | stimulated and the sealing performance may deteriorate by the dimension of a diaphragm changing.

  Therefore, in the present invention, an elastic spring portion is formed at both ends or one end of the diaphragm by bending the end portion of the diaphragm formed of metal. Further, the spring portion is pressed by the pressing member against the first coupling portion provided on the side surface of the housing and / or the second coupling portion provided on the side surface of the plunger. Thereby, the sealing property between the diaphragm and the housing and / or between the diaphragm and the plunger can be ensured by a simple structure. Further, when the housing and the plunger are relatively moved, the spring portion is appropriately deformed, so that the degree of freedom of the diaphragm in the first coupling portion or the second coupling portion can be increased. As a result, it is possible to suppress the load from being concentrated near the first coupling portion or the second coupling portion, and as a result, it is possible to improve the durability of the sealed hydraulic damper.

  In addition, even when the dimension of the diaphragm changes at high temperature, the spring part can absorb the dimension change, and thermal stress is applied to the diaphragm, thereby promoting metal fatigue of the diaphragm. It is possible to suppress the deterioration of the sealing performance. As a result, the environmental resistance of the sealed hydraulic damper can be improved.

  In the above, when the spring portion is formed only at one end of the diaphragm and the spring portion is pressed only to the first coupling portion, the other end of the diaphragm is welded or bonded. You may couple | bond with the said 2nd coupling | bond part by the method of. Moreover, when it is set as the structure which presses the said spring part only to a said 2nd coupling part, about the other end of the said diaphragm, you may couple | bond with the said 1st coupling part by methods, such as welding or adhesion | attachment. Whether the spring portion is formed only at one end of the diaphragm or at both ends may be determined by the magnitude and distribution of the load on the diaphragm.

  Here, the pressing member may be pressed so that the spring portion is elastically deformed to a compression rate of 50% or less with respect to its elastic limit when assembled at room temperature. By doing so, the compression ratio of the spring portion is about 50% with respect to its elastic limit even at high temperatures, and good spring properties can be maintained even at high temperatures. And at the time of high temperature, it can suppress more reliably that the load with respect to the said diaphragm and the sealing performance deteriorate by the dimensional change of the said diaphragm. As a result, the environmental resistance of the sealed hydraulic damper can be improved more reliably.

Further, in the present invention, when a spring portion formed by bending an end portion of the diaphragm is provided in a portion that is coupled to the first coupling portion,
The first coupling portion is a first groove portion formed by a groove provided on a side surface of the housing substantially perpendicular to a sliding direction of the plunger,
A spring portion provided at a portion coupled to the first groove portion is formed by bending an end portion of the diaphragm in an annular shape on the side facing the first groove portion when the diaphragm is coupled to the first groove portion. And
The pressing member has a hollow shape that is open at both ends, and can accommodate therein a portion that is coupled to the first groove portion of the diaphragm, and is a portion that is plastically deformed by caulking work and is coupled to the first groove portion. A caulking member that presses the spring portion provided on the first groove portion,
The diaphragm may be coupled to the first groove portion by being crimped by the caulking member in a state where a spring portion provided in a portion coupled to the first groove portion is intruded into the first groove portion. .

If it carries out like this, the said diaphragm and the said housing can be assembled | attached easily by making the said spring part penetrate | invade and fit in the said 1st groove part. Further, the caulking member is put on the spring portion in this state. In other words, in a state where the diaphragm and the housing are assembled, the diaphragm and the housing are inserted into the inside of the substantially cylindrical caulking member, and then the caulking work is performed. Thus, the first groove and the spring can be easily and reliably coupled.

  Further, in this case, in the direction parallel to the movement direction of the plunger, the spring portion is inserted into the first groove portion and is thus fitted, so that the relative position of the spring portion with respect to the housing is restricted. However, in the present invention, when the diaphragm is pulled in a direction parallel to the movement direction of the plunger, the entire diaphragm moves reversibly with respect to the housing by the elasticity of the spring portion. Can do. Further, the spring portion can be deformed, moved, and rotated within the range of restriction of the first groove portion. As a result, the degree of freedom in the first groove portion of the housing can be greatly increased, and an excessive load can be suppressed from being generated in the vicinity of the first groove portion of the diaphragm.

  Here, it is preferable that the first groove portion is provided in a closed curve shape over the entire circumference of the side surface of the housing. Moreover, it is desirable that the spring portion is formed over the entire portion of the diaphragm that is coupled to the first groove portion. Furthermore, it is preferable that a cross section of the diaphragm in a portion coupled with the first groove is substantially the same shape as the outer periphery of the housing in the first groove. If it carries out like this, the said diaphragm and the said housing can be couple | bonded more reliably, and a sealing performance can be improved.

Further, in the present invention, when a spring portion formed by bending an end portion of the diaphragm is provided in a portion that is coupled to the second coupling portion,
A columnar portion projecting toward the open end side of the housing is provided on the open end side surface of the plunger,
The second coupling portion is a second groove portion including a groove provided on a side surface of the columnar portion substantially perpendicularly to a sliding direction of the plunger.
A spring portion provided at a portion coupled to the second groove portion is formed by bending an end portion of the diaphragm in an annular shape on the side facing the second groove portion when the diaphragm is coupled to the second groove portion. And
The pressing member is a cap that is attached to the columnar portion by fitting the inner hole portion with the columnar portion;
A spring portion provided at a portion where the cap is mounted on the columnar portion and coupled to the second groove portion in a state where a spring portion provided at a portion coupled with the second groove portion is inserted into the second groove portion. However, the diaphragm may be coupled to the second groove portion by being pressed against the second groove portion by the inner hole portion.

  If it carries out like this, the said diaphragm and the said plunger can be easily assembled | attached by making the said spring part penetrate | invade and fit in the 2nd groove part provided in the columnar part of the said plunger like the above-mentioned description. Furthermore, by attaching the cap to the columnar part in this state, the second groove part and the spring part can be easily combined. Moreover, the freedom degree in the said 2nd groove part of the said diaphragm can be increased significantly, and it can suppress that an excessive load arises near the 2nd groove part of the said diaphragm.

  Also in this case, it is desirable that the second groove portion is provided in a closed curve shape over the entire circumference of the side surface of the columnar portion. In addition, it is preferable that the spring portion is formed over the entire area of the diaphragm that is coupled to the second groove portion. Furthermore, it is preferable that a cross section of the diaphragm in a portion coupled to the second groove portion has substantially the same shape as an outer periphery of the columnar portion in the second groove portion. If it carries out like this, the said diaphragm and the said plunger can be couple | bonded more reliably, and a sealing performance can be improved.

  The means for solving the problems in the present invention can be used in combination as much as possible.

  In the present invention, it is possible to ensure sufficient impermeability of the diaphragm in the sealed hydraulic damper to oxygen and a lubricant, and to improve the durability of the sealed hydraulic damper.

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

  FIG. 1 is a view showing a sealed hydraulic damper in the present embodiment. A sealed hydraulic damper 1 shown in FIG. 1 is provided with a substantially cylindrical housing 2 whose upper end in the drawing is an open end and whose lower end is closed. A substantially cylindrical plunger 3 is also disposed inside the housing 2. A sufficient clearance is secured between the outer peripheral surface 3a of the plunger 3 and the inner peripheral surface 2a of the housing 2 in order for the plunger 3 to reciprocate by sliding inside the housing 2.

  A retainer clip 12 that functions as a stopper of the plunger 3 is attached to the upper end portion of the inner peripheral surface 2 a of the housing 2. Therefore, the axial displacement of the plunger 3 in the housing 2 is restricted by the bottom surface 2 b of the housing 2 and the retainer clip 12. Note that a stem end receiving surface 2c is provided on the back side of the bottom surface of the housing 2 so that the stem end portion 20 of the intake / exhaust valve comes into contact therewith.

  A columnar portion 3b having a substantially cylindrical shape is provided in the central portion of the plunger 3 on the open end side of the housing 2. The cap 4 is attached to the columnar portion 3b by fitting the inner hole portion 4a with the columnar portion 3b from above in the figure. On the upper surface of the cap 4, an armature tip 30 in the electromagnetically driven valve is disposed. The armature tip 30 pushes down the upper surface of the cap 4 with energization during the valve opening operation of the electromagnetically driven valve. As a result, the plunger 3 and the housing 2 are lowered, and further, the stem end portion 20 in contact with the valve receiving surface 2c is lowered. As a result, the intake / exhaust valve is opened.

  Further, in this embodiment, the diaphragm 8 is coupled to the housing 2 at the portion A in FIG. 1 and is coupled to the plunger 3 at the portion B in FIG. 1, so that the diaphragm 8 covers the open end of the housing 2. ing. A reservoir chamber 9 is mainly defined by the diaphragm 8 and the plunger 3. The high pressure chamber 5 is defined mainly by the lower surface 3 c of the plunger 3 and the bottom surface 2 b of the housing 2. The reservoir chamber 9 and the high-pressure chamber 5 are filled with silicon oil.

  The plunger 3 is formed with an oil passage 3d provided so as to communicate between the side surface near the base of the columnar portion 3b and the lower surface 3c of the plunger 3. The high pressure chamber 5 is provided with a plate 6, a plunger spring 7 and a check ball 10. The plate 6 holds the check ball 10 in a state where the outer peripheral portion is supported by the upper end of the plunger spring 7. When the plunger 3 is stationary, the upper end of the plunger spring 7 abuts against the lower surface 3c of the plunger 3 so that the check ball 10 closes one end of the oil passage 3d.

  On the other hand, the lower end of the plunger spring 7 is in contact with the bottom surface 2b of the housing 2, and always urges the plunger 3 and the plate 6 upward. The check ball 10 functions as a check valve that opens only when the high pressure chamber 5 is at a lower pressure than the reservoir chamber 9.

  Next, the operation of the sealed hydraulic damper 1 will be described with reference to FIG. Here, as described above, the armature 30 applies a downward load in FIG. 1 to the cap 4 with energization during the valve opening operation of the electromagnetically driven valve. The stem end 20 of the intake / exhaust valve is in contact with the valve receiving surface 2c. The stem end 20 of the intake / exhaust valve is closed by a valve spring (not shown), ie, upward in FIG. It is energized.

  Here, the figure shown in FIG. 1 shows a state where the plunger 3 is fully extended and is in a state before being assembled to the internal combustion engine. In a state where the sealed hydraulic damper 1 is assembled to the internal combustion engine, the plunger 3 is in the vicinity of half of the plunger stroke as shown in FIG. When the armature 30 of the electromagnetically driven valve starts to descend from this state, the force in the valve opening direction presses the cap 4, and this pressing force acts on the plunger 3. When the force acting on the plunger 3 exceeds the urging force of the plunger spring 7, the plunger 3 is pressed downward and the silicon oil in the high pressure chamber 5 is pressurized. Therefore, the hydraulic pressure in the high pressure chamber 5 becomes higher than the hydraulic pressure in the reservoir chamber 9, and the oil passage 3 d is closed by the check ball 10.

  When the oil passage 3d is closed, the transfer of silicon oil between the high pressure chamber 5 and the reservoir chamber 9 is stopped. Therefore, the force acting on the plunger 3 is transmitted to the housing 2 through the high pressure chamber 5, and the plunger 3 is displaced downward while receiving the reaction force of the plunger spring 7. Accordingly, as indicated by a black arrow in FIG. 2A, silicon oil gradually flows from the high pressure chamber 4 through the clearance between the outer peripheral surface 3 a of the plunger 3 and the inner peripheral surface 2 a of the housing 2. It leaks out and the sealed hydraulic damper 1 gradually contracts.

  On the other hand, when the electromagnetically driven valve performs a valve closing operation, the armature 30 starts an upward movement. Accordingly, the stem end portion 20 of the intake / exhaust valve starts to rise in accordance with the urging force of the valve spring. Further, when the intake / exhaust valve reaches the fully closed position, the reaction force from the valve spring does not act on the housing 2. At this time, the plunger 3 tries to slide upward with respect to the housing 2 by the urging force of the plunger spring 7, and the hydraulic pressure in the high pressure chamber 5 decreases.

  When the pressure in the high-pressure chamber 5 becomes lower than that in the reservoir chamber 9, the check ball 10 is separated from the opening of the oil passage 3d, so that the high-pressure chamber 5 and the reservoir chamber 9 communicate with each other in FIG. The silicon oil returns from the reservoir chamber 9 to the high pressure chamber 5 as indicated by a black arrow. As a result, the plunger 3 is raised until the cap 4 comes into contact with the armature 30, and the gap with the armature 30 is set to 0 (zero).

  That is, when the intake / exhaust valve is opened, the housing 2 is displaced while receiving the reaction force of the valve spring 7, and oil gradually leaks from the high pressure chamber 5 into the reservoir chamber 9, so that the entire sealed hydraulic damper 1 is Shrink. When the intake / exhaust valve reaches the fully closed position, the plunger 3 slides upward, so that the sealed hydraulic damper 1 is extended by the contraction.

  In this way, the sealed hydraulic damper 1 repeats constant expansion and contraction at all times during operation to buffer the operations of the armature 30 of the electromagnetically driven valve and the stem end 20 of the intake / exhaust valve. Suppresses collision noise. The diaphragm 8 is deformed by the expansion / contraction operation and the pressure change in the reservoir chamber 9 accompanying the expansion / contraction operation.

  Next, the diaphragm 8 and its mounting structure in the present embodiment will be described in detail. FIG. 3A shows a cross-sectional view of the diaphragm 8. The diaphragm 8 is formed of a thin film of ferritic stainless steel, and in this embodiment, its thickness is about 200 μm. When viewed from above in FIG. 3, it has a substantially circular shape. That is, the diaphragm 8 has a shape as a rotating body formed by rotating the diagram shown in FIG. 3A around its center line.

  A first spring portion 8 a is formed at the lower end of the diaphragm 8. On the other hand, a second spring portion 8 b is formed at the upper end of the diaphragm 8. FIG. 3B shows an enlarged view of the first spring portion 8a in the present embodiment. As shown in FIG. 3B, in the first spring portion 8a, the end portion of the diaphragm 8 is bent inward (in the housing 2 side in FIG. 1) in a substantially annular shape. From this state, an elastic force is generated by further deforming this portion. FIG. 3C shows another example of the mode of the diaphragm 8 in the first spring portion. By setting it as the 1st spring part 8a 'of such an aspect, Young's modulus can be made lower than the 1st spring part 8a shown in FIG.3 (b). 3A and 3B show the first spring portion 8a and the modified example 8a ′ of the first spring portion of the two spring portions of the diaphragm 8, the second spring portion 8b. A similar aspect can be taken.

  FIG. 4 shows a mounting structure of the first spring portion 8a and the second spring portion 8b in the present embodiment. FIG. 4A is an enlarged view of a portion A in FIG. 1 and shows a mounting structure of the first spring portion 8a. FIG. 4B is an enlarged view of a portion B in FIG. 1 and shows a mounting structure of the second spring portion 8b.

  As shown in FIG. 4A, a first groove 2 d is provided on the outer peripheral surface of the housing 2. The first groove 2d is formed over the entire outer peripheral surface of the housing 2 on a plane perpendicular to the central axis of the housing 2 in FIG. That is, the first groove 2d is formed in a perfect circle shape so as to surround the housing 2 as a whole. Here, the diameter R1 of the outer peripheral surface of the housing 2 is larger than the inner diameter R2 of the diaphragm 8 in the first spring portion 8a. On the other hand, the outer diameter R3 of the housing 2 in the first groove 2d is slightly smaller than or equal to R2. When the diaphragm 8 is attached to the housing 2, the opening on the first spring portion 8 a side of the diaphragm 8 is covered from the open end side of the cylindrical housing 2. At this time, although R1 is larger than R2, the opening on the first spring portion 8a side of the diaphragm 8 can be covered on the housing 2 by elastic deformation of the first spring portion 8a.

  When the diaphragm 8 is further covered toward the other end of the housing 2, the first spring portion 8 a is fitted into the first groove portion 2 d, so that the diaphragm 8 is fixed to the housing 2. Furthermore, the crimping member 11 which has a cylindrical shape is covered from the top (state of the dashed-dotted line in Fig.4 (a)). The position of the caulking member 11 in the axial direction of the housing 2 is regulated by a caulking member regulating portion 2 e provided in the housing 2. Then, the housing 2 is caulked from the outside of the caulking member 11 in a direction in which the housing 2 is tightened together with the diaphragm 8 using a caulking jig (not shown). Here, the inner diameter R4 of the caulking member 11 before the caulking work is set larger than the outer diameter R5 of the diaphragm 8, so that the diaphragm 8 can be easily covered. Then, after the caulking work, the first spring portion 8a is prevented from being detached from the first mounting hole 2d by the tip portion 11a of the caulking member 11. As a result, the axial position of the diaphragm 8 in the housing 2 is regulated.

Further, by the caulking operation, the portion 11b of the caulking member 11 facing the first spring portion 8a presses the first spring portion 8a toward the housing 2, and the first compression portion 11b is compressed to 50% or less of the elastic limit. 1 Spring part 8a is elastically deformed. In addition, the portion 11c of the crimping member 11 that faces the portion other than the first spring portion 8a of the diaphragm 8 does not lose the degree of freedom because the diaphragm 8 is sandwiched between the crimping member 11 and the housing 2. It can be crimped to such a position that a certain clearance is ensured between the housing 2 and the housing 2.

  As described above, when the first spring portion 8a of the diaphragm 8 is coupled to the first groove portion 2d of the housing 2, when the plunger 3 moves relative to the housing 2, the diaphragm is moved along with the movement. 8 is deformed. Further, with the movement of the silicon oil inside the diaphragm 8, a force for expanding or contracting the diaphragm 8 acts on the diaphragm 8.

  Even in such a case, the first spring portion 8a in the diaphragm 8 is elastically deformed as indicated by a broken line and a white arrow in FIG. 4A, and therefore an excessive load is concentrated on a specific portion of the diaphragm 8. Can be suppressed. Further, when the position of the plunger 3 with respect to the housing 2 is restored, the state of the diaphragm 8 is also restored by the elastic force of the first spring portion 8a. Therefore, it is possible to suppress fatigue of a specific portion of the diaphragm 8 while maintaining good sealing performance by the diaphragm 8. As a result, the sealing performance and durability of the diaphragm 8 can be improved.

  In addition, even when the dimensions of the diaphragm 8 expand due to expansion of the diaphragm 8 in a high temperature environment, the first spring portion 8a can be elastically deformed to absorb the dimensional change, and excessive thermal stress is generated. It can suppress that it applies to the diaphragm 8, or a sealing performance deteriorates. As a result, the environmental resistance of the diaphragm 8 can be improved.

  Furthermore, since the first spring portion 8a is elastically deformed to a compression rate of 50% or less with respect to its elastic limit by the caulking member 11 at the time of normal temperature assembly, the first spring portion 8a is excessively deformed even at a high temperature. It is possible to suppress the first spring portion 8a from losing its resilience when an excessive load acts and exceeds the elastic limit. And at the time of high temperature, it can suppress more reliably that the thermal stress concerning the diaphragm 8 increases by the dimensional change of the diaphragm 8, and a sealing performance deteriorates. As a result, the environmental resistance of the sealed hydraulic damper can be improved more reliably.

  Next, the mounting structure of the second spring portion 8b will be described. As shown in FIG. 4B, the columnar portion 3b of the plunger 3 is provided with a second groove portion 3e. 4A, when the diaphragm 8 is attached to the columnar portion 3b of the plunger 3, the opening on the second spring portion 8b side of the diaphragm 8 is covered from the tip side of the columnar portion 3b. The second spring portion 8b is fixed by being fitted into the second groove portion 3e (however, in the assembly process of the sealed hydraulic damper 1, the plunger 3 needs to be assembled to the diaphragm 8 before the housing 2). .)

  Further, the cap 4 is attached from the tip side of the columnar portion 3b. At this time, the inner diameter R11 of the inner hole portion 4a of the cap 4 is set to be larger than the outer diameter R12 on the base side of the second groove portion 3e in the columnar portion 3b, and the diaphragm 8 is interposed between the columnar portion 3a and the cap 4. Clearance is secured so as not to lose the degree of freedom. On the other hand, the second spring portion 8b is pressed against the second groove 3e by the cap 4 in a state of being elastically deformed to a compression rate of 50% or less with respect to its elastic limit.

As a result, when the diaphragm 8 is deformed due to the relative movement between the housing 2 and the plunger 3, the second spring portion 8b is elastically deformed as shown by the broken line and the white arrow in FIG. In addition, an excessive load is not concentrated on a specific portion of the diaphragm 8. Also, the lower end 4b of the cap 4 shown in FIG. 4 is chamfered, and a radius of curvature equivalent to R of the chamfer is set at a bending point in the portion of the diaphragm 8 that contacts the portion. . Accordingly, the diaphragm 8 is prevented from coming into contact with the sharply pointed part with the relative movement of the plunger 3 with respect to the housing 2, and the durability of the diaphragm 8 can be improved.

  In addition, even when the dimensions of the diaphragm 8 expand due to expansion of the diaphragm 8 in a high temperature environment, the second spring portion 8b can be elastically deformed to absorb the dimensional change, and excessive thermal stress is generated. It can suppress that it applies to the diaphragm 8, or a sealing performance deteriorates. As a result, the environmental resistance of the diaphragm 8 can be improved.

  Further, since the second spring portion 8b is fixed in a state of being elastically deformed to a compression rate of 50% or less with respect to its elastic limit by the cap 4 at the time of assembly at room temperature, the second spring portion 8b is at a high temperature. When an excessive load acts on 8b and exceeds the elastic limit, it is possible to suppress the second spring portion 8b from losing its resilience. And at the time of high temperature, it can suppress more reliably that the thermal stress in the diaphragm 8 increases by the dimensional change of the diaphragm 8, and a sealing performance deteriorates. As a result, it is possible to more reliably improve the environmental resistance of the sealed hydraulic damper.

  As described above, in this embodiment, the diaphragm 8 made of metal has the first spring portion 8a and the second spring portion 8b at both ends thereof. The caulking member 11 and the cap 4 seal the silicon oil using the elastic force generated by pressing them. Therefore, good sealing performance can be ensured.

  Further, when the plunger 3 moves relative to the housing 2, the first spring portion 8 a and the second spring portion 8 b are appropriately deformed, and therefore, between the diaphragm 8 and the housing 2, and between the columnar portion 3 b and the housing 2. The degree of freedom in the coupling between them can be increased. Therefore, it is possible to suppress an excessive load from being applied to a specific portion of the diaphragm 8. As a result, even when a metal is used as the material of the diaphragm 8, the durability of the diaphragm 8 can be improved.

  In addition, even when the dimensions of the diaphragm 8 expand due to expansion of the diaphragm 8 in a high temperature environment, the dimensional change can be absorbed by elastic deformation of the first spring portion 8a and the second spring portion 8b. Further, it is possible to prevent the diaphragm 8 from being excessively subjected to thermal stress and the sealing performance from being deteriorated. As a result, the environmental resistance of the diaphragm 8 can be improved.

  Furthermore, since the first spring portion 8a and the second spring portion 8b are elastically deformed to a compression rate of 50% or less with respect to the elastic limit and silicon oil is sealed at the time of normal temperature assembly, The first spring portion 8a and the second spring portion 8b do not exceed the elastic limit. Thereby, at high temperature, it can suppress more reliably that the thermal stress in the diaphragm 8 increases by the dimensional change of the diaphragm 8, and a sealing performance deteriorates. As a result, it is possible to more reliably improve the environmental resistance of the sealed hydraulic damper.

In addition, in FIG. 5, another example of the attachment structure of the 1st spring part in a present Example is shown. Here, the first spring portion 8 a ″ is formed by bending the end portion of the diaphragm 8 in an annular shape on the outer peripheral side, that is, on the opposite side to the housing 2. Further, in the example shown in FIG. 5, the first groove portion 2 d described in FIG. 4 is not provided, and the function thereof is given to the crimping member 21. Further, by using a spring material as the material of the caulking member 21, the sealing performance by the first spring portion 8 a ″ and the restoring performance of the diaphragm 8 during the relative movement of the plunger 3 with respect to the housing 2 are obtained. Not only 'but also the elastic force of the caulking member 21 was used for improvement.

  In FIG. 5, a spring material such as an SCP material or SUS410 maraging steel is used for the caulking member 21. In the caulking work, the position of the caulking member 21 relative to the housing 2 is determined by firmly caulking the first caulking portion 21a with respect to the housing 2 without a gap. Further, the second caulking portion 21b is caulked while maintaining a clearance such that the diaphragm 8 is sandwiched between the housing 2 and the caulking member 21 and the degree of freedom is not lost.

  Accordingly, the position of the first spring portion 8a ″ can be regulated by the space between the first caulking portion 21a and the second caulking position 21b in the caulking member 21. At the same time, the first spring portion 8a ″ can be pressed toward the housing 2 by the portion 21c facing the first spring portion 8a ″. Furthermore, when the plunger 3 moves relative to the housing 2, the restoring force of the diaphragm 8 is generated not only by the deformation of the first spring portion 8 a ″ but also by deformation near the second caulking portion 21 b of the caulking member 21. Can be made.

  According to this configuration, the seal position of the diaphragm 8 with respect to the housing 2 can be changed by changing the position of the first caulking portion 21a, and further, the Young's modulus when generating the restoring force of the diaphragm 8 The degree of freedom of setting can be increased.

  In the above embodiment, the example in which the sealed hydraulic damper 1 is applied to an electromagnetically driven valve operating device has been described. However, the present invention may also be applied to a roller rocker valve operating device. Is possible. Further, the present invention can be applied to an adjustment mechanism that performs automatic tappet clearance.

  In addition, since the sealed hydraulic damper in the present invention does not need to supply oil from the outside, the apparatus itself can be downsized. Therefore, the layout of the apparatus can be facilitated even when applied to the roller rocker type valve operating apparatus and the adjustment mechanism that performs automatic tappet clearance.

It is the figure which showed schematic structure of the sealing type hydraulic damper in the Example of this invention. It is a figure explaining operation | movement of the sealed hydraulic damper in the Example of this invention. It is a figure which shows the detail of the diaphragm and the 1st spring part in the Example of this invention. It is a figure which shows the attachment structure of the diaphragm in the Example of this invention. It is a figure which shows another example of the attachment structure of the diaphragm in the Example of this invention.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 ... Sealing hydraulic damper 2 ... Housing 2a ... Inner peripheral surface 2b ... Bottom 2c ... Stem end receiving surface 2d ... 1st groove part 2e ... Caulking member regulation part 3. .... Plunger 3a ... Outer peripheral surface 3b ... Columnar part 3c ... Lower surface 3d ... Oil passage 3e ... Second groove part 4 ... Cap 4a ... Inner hole part 4b ... Lower end 5 ... High pressure chamber 6 ... Plate 7 ... Plunger spring 8 ... Diaphragm 8a, 8a ', 8a "... 1st spring part 8b ... 2nd spring part 9 ... Reservoir chamber 10 ··· Check ball 11 ··· Caulking member 11a ··· Tip portion 11b · Portion corresponding to first spring portion 11c · Portion other than first spring portion in diaphragm 12 ... Retainer clip 21 ... Oak Member 21a · · · first caulking portion 21b · · · second caulking portions 21c · · · portion facing the first spring portion

Claims (3)

A hollow housing with one end open and the other closed;
A plunger slidably inscribed in the housing;
A first coupling portion provided on a side surface of the housing and a diaphragm covering the open end of the housing by coupling with a second coupling portion provided on the open end side surface of the plunger;
A high-pressure chamber is formed by being surrounded by the inner surface on the other end side of the housing and the surface on the other end side of the plunger,
A reservoir chamber is formed by being surrounded by the surface of the open end side of the plunger and the diaphragm,
The high pressure chamber and the reservoir chamber are filled with oil,
A sealed hydraulic damper provided with a flow passage through which the oil flows between the high pressure chamber and the reservoir chamber,
The diaphragm is formed of a metal, and a spring portion formed by bending an end portion of the diaphragm is formed in a portion coupled to the first coupling portion and / or a portion coupled to the second coupling portion. Provided,
A sealed hydraulic damper, further comprising a pressing member that presses the spring portion against the first coupling portion and / or the second coupling portion. When a spring portion formed by bending an end portion of the diaphragm is provided in a portion that is coupled to the first coupling portion,
The first coupling portion is a first groove portion formed by a groove provided on a side surface of the housing substantially perpendicular to a sliding direction of the plunger,
A spring portion provided at a portion coupled to the first groove portion is formed by bending an end portion of the diaphragm in an annular shape on the side facing the first groove portion when the diaphragm is coupled to the first groove portion. And
The pressing member has a hollow shape that is open at both ends, and can accommodate therein a portion that is coupled to the first groove portion of the diaphragm, and is a portion that is plastically deformed by caulking work and is coupled to the first groove portion. A caulking member that presses the spring portion provided on the first groove portion,
The diaphragm is coupled to the first groove portion by being crimped by the caulking member in a state where a spring portion provided in a portion coupled to the first groove portion is inserted into the first groove portion. The sealed hydraulic damper according to claim 1. When a spring portion formed by bending an end portion of the diaphragm is provided in a portion that is coupled to the second coupling portion,
A columnar portion projecting toward the open end side of the housing is provided on the open end side surface of the plunger,
The second coupling portion is a second groove portion including a groove provided on a side surface of the columnar portion substantially perpendicularly to a sliding direction of the plunger.
A spring portion provided at a portion coupled to the second groove portion is formed by bending an end portion of the diaphragm in an annular shape on the side facing the second groove portion when the diaphragm is coupled to the second groove portion. And
The pressing member is a cap that is attached to the columnar portion by fitting the inner hole portion with the columnar portion;
A spring portion provided at a portion where the cap is mounted on the columnar portion and coupled to the second groove portion in a state where a spring portion provided at a portion coupled with the second groove portion is inserted into the second groove portion. 3. The sealed hydraulic damper according to claim 1, wherein the diaphragm is coupled to the second groove portion by being pressed against the second groove portion by the inner hole portion.

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