JP4020263B2 - Viscous fluid filled damper - Google Patents

Description

  The present invention relates to discs such as CDs, CD-ROMs, DVDs, DVD-ROMs, DVD-RAMs, and magneto-optical disks used for audio equipment, video equipment, information equipment, various precision equipments including in-vehicle use and consumer use. More particularly, the present invention relates to a viscous fluid-filled damper that attenuates vibration of a mechanical chassis on which a disk playback mechanism is mounted.

  The disk reproduction mechanism reproduces recorded data from the disk by rotating the disk at a high speed and moving a non-contact reading device such as an optical pickup or a magnetic head close to the disk. Therefore, internal vibrations may be generated by vibrations caused by the operation of the drive system mechanical elements of the disk or non-contact reader, or vibrations caused by high-speed rotation of the so-called eccentric disk. In addition, for example, a car audio device and a car navigation device such as a car-mounted disk device may be subject to running vibration and shock, and a portable disk device may be subject to disturbance vibration and shock when carried. Acts on the mechanical chassis as an impact. When these disturbance vibrations, disturbance vibrations, and shocks act on the mechanical chassis, a reproduction error that cannot be corrected by software means may occur. Therefore, a coil spring and a viscous fluid-filled damper are usually interposed between the mechanical chassis and the housing in which the mechanical chassis is built.

  A conventional viscous fluid-filled damper 1 has a structure in which a highly viscous viscous fluid 3 such as silicone oil is sealed in a sealed container 2 as shown in FIG. The sealed container 2 includes a cylindrical peripheral wall portion 4 made of a hard resin such as polypropylene, a dome-shaped flexible membrane portion 5 made of a rubber-like elastic body such as a thermoplastic elastomer that is fixed and closed at one end thereof, and a peripheral wall. It is comprised with the cover body 6 which consists of hard resin, such as a polypropylene, which adheres to the other end of the part 4 and obstruct | occludes.

  The attachment structure is such that the attachment shaft 9 provided in the mechanical chassis 8 is inserted into the insertion recess 7a of the stirring cylinder portion 7 formed integrally with the flexible membrane portion 5, and the attachment screw N is inserted into the hole 6a of the lid body 6. Is inserted and fixed to the side wall 10a of the housing 10 of the disk device by screwing. However, in this mounting structure, the static load of the mechanical chassis 8 is directly applied to the flexible film portion 5 to cause distortion deformation, and the damping effect is extremely inferior. Therefore, the static load of the mechanical chassis 8 is supported by, for example, a plurality of coil springs 10b attached to the side wall 10a, so that the static load is hardly applied to the flexible film portion 5 of the viscous fluid-filled damper 1. It is normal. As another mounting structure, there is a case where the viscous fluid-filled damper 1 is fixed to the bottom wall 10c of the housing 10 as shown by a two-dot chain line in FIG. 10 b prevents the static load of the mechanical chassis 8 from being applied to the viscous fluid-filled damper 1. In any mounting structure, the vibration transmitted between the mechanical chassis 8 and the housing 10 is insulated by the expansion and contraction of the coil spring 10b, and the viscous fluid-filled damper 1 attenuates the free vibration of the coil spring 10b. To function.

As a prior art document disclosing such prior art, the present applicant has known the following.
Japanese Patent Laid-Open No. 2000-220681 (FIG. 3) Japanese Patent Laying-Open No. 2001-271867 (FIG. 9)

  By the way, in such a viscous fluid-filled damper 1, the vibration of the mechanical chassis 8 can normally be effectively damped by the elastic deformation of the flexible film portion 5 and the viscosity of the viscous fluid 3 stirred by the stirring cylinder portion 7. However, when vibration in the vicinity of the natural frequency of the vibration isolation system, particularly in the low frequency region of 10 to 30 Hz, is applied, the amplitude of the mechanical chassis 8 increases due to the resonance phenomenon. Particularly, in-vehicle or portable disk devices are easily subjected to an impact, and when the impact is applied, the mechanical chassis 8 is momentarily displaced greatly. In these cases, the conventional viscous fluid-filled damper 1 has a problem that the mounting shaft 9 may be disengaged from the normal insertion state of the insertion recess 7a.

  That is, normally, the engagement head 9a of the mounting shaft 9 abuts and engages with the engagement recess 7b of the insertion recess 7a having a relative shape with the engagement head 9a. A regular plug-in state is maintained.

However, when the mechanical chassis 8 is largely displaced due to the resonance or impact as described above, the engaging head 9a is engaged with the engaging recess 7b made of a rubber-like elastic body by the urging generated in the pulling direction as shown in FIG. May be deformed so as to spread and disengage. When the insertion state of the mounting shaft 9 becomes incomplete in this way, the stirring action of the viscous fluid 3 is diminished and the original damping performance is impaired. Further, if the insertion state is continuously imperfect while the insertion state is incomplete, the mounting shaft 9 moves up and down inside the insertion recess 7a, the friction cylinder 3 is damaged by the friction, and the viscous fluid 3 is exposed to the outside. There is a risk of leakage. And if it completely escapes from the incomplete state, the damping performance can no longer be exhibited at all.

  In addition, when the mechanical chassis 8 is greatly displaced due to the above-described resonance vibration or impact, the stirring cylinder portion 7 may collide with the peripheral wall portion 4 or the lid portion 6 made of hard resin and break. Also in this case, the viscous fluid 3 flows out to the outside and the damping performance is impaired, and the mechanical chassis 8 and the like are also soiled by the flowed viscous fluid 3.

  The conventional problems as described above are dealt with by changing the material of the stirring cylinder portion 7 to one having a high hardness that can reliably hold the mounting shaft 9 or one having a high durability that is hard to break and hard to wear. There is a way. However, in this case, the material of the stirring cylinder portion 7 and the series of flexible membrane portions 5 are also changed at the same time, and there is a problem that the vibration damping performance is lowered.

  There is also a coping method in which the holding force of the mounting shaft 7 is improved by making the inner diameter of the insertion recess 7 a of the stirring cylinder portion 7 smaller than the outer diameter of the mounting shaft 9. However, this increases the difficulty of inserting the mounting shaft 7 into the insertion recess 7a, and in order to insert the stirring cylinder portion 7 into the proper position without contacting the peripheral wall portion 4 and the lid body 6, Skilled skills are required.

  The present invention has been made against the background of the prior art as described above. An object of the present invention is to make it difficult for the mounting shaft to come out of the stirring cylinder part and to prevent the stirring cylinder part from being broken easily without impairing the vibration damping performance of the viscous fluid-filled damper.

In order to achieve the above object, the present invention includes a sealed container and a viscous fluid sealed in the sealed container, and the sealed chassis is provided with a mechanical chassis having a disk-shaped recording medium reproducing device, or the mechanical chassis. An agitation tube portion that holds an attachment shaft formed by inserting a retaining portion that bulges radially outward in a shaft portion protruding from any of the housings to be accommodated; and
A viscous fluid-filled damper provided with a flexible membrane portion made of a rubber-like elastic body that supports the stirring cylinder portion in a floating state, and the stirring cylinder portion is formed of a rubber-like elastic body continuous with the flexible membrane portion In addition, the movement of the retaining portion in the removal direction is directed outward in the radial direction of the rubber-like elastic body at least in the corresponding portion closer to the shaft portion than the boundary between the shaft portion and the retaining portion of the mounting shaft in the stirring cylinder portion. The hard wall part which controls by deform | transforming into is provided , and this hard wall part is a molded object fixed to the rubber-like elastic body which comprises a stirring cylinder part by mold forming .

  When the mounting shaft is about to be displaced greatly from the normal insertion state due to resonance vibration or impact, the retaining portion of the mounting shaft is deformed so as to push the stirring cylinder portion outward. In the present invention, deformation of the stirring tube portion is suppressed by the hard wall portion at a position closer to the shaft portion side than the boundary between the shaft portion and the retaining portion of the mounting shaft. For this reason, even if it receives a resonance vibration or an impact, the mounting shaft is difficult to come off and a strong holding force can be exhibited. And since the remaining part of the stirring cylinder part excluding the hard wall part is a rubber-like elastic body continuous with the flexible film part, by elastic deformation of the flexible film part and stirring of the viscous fluid by the stirring cylinder part, Excellent vibration damping effect can be obtained.

  The viscous fluid-filled damper according to the present invention is configured such that a hard wall portion is also formed on the outer surface on the front end side of the stirring tube portion.

  In the present invention, since the hard wall portion is also formed on the outer surface on the tip side of the stirring tube portion, the stirring tube portion is difficult to break even if it collides with the inner surface of the sealed container by being greatly displaced by receiving resonance vibration or impact, High vibration durability can be exhibited.

  The hard wall portion of the viscous fluid-filled damper of the present invention is made of a material having a hardness capable of suppressing deformation that spreads the stirring cylinder portion by the retaining portion of the mounting shaft, such as a synthetic resin or a metal. it can.

  As a specific example of the hard wall portion in the viscous fluid-filled damper of the present invention, it can be configured as a molded body fixed to a rubber-like elastic body constituting the stirring cylinder portion by molding. According to this, the adhering strength between the hard wall portion and the stirring tube portion can be increased. As the manufacturing method, there are a method of forming the hard wall portion and the stirring tube portion in two colors, and a method of inserting the hard wall portion when forming the stirring tube portion.

  In addition, specifically, the hard wall portion can be configured to be formed in an endless annular shape over the entire circumference of the stirring cylinder portion, thereby making it difficult to deform the stirring cylinder portion over the entire circumference. In addition, the hard wall portion of the present invention can be configured to be formed intermittently in the circumferential direction of the stirring tube portion, and this also makes it difficult to deform the stirring tube portion. In this case, more specifically, a resin-molded product having a hard wall portion having a cylindrical base portion and a plurality of projecting piece portions formed in a cantilever shape from the cylindrical base portion in parallel with the axis. The hard wall portion can be configured as an annular resin molded body having slits along the axial direction and spaced apart in the circumferential direction.

  As another specific example of the hard wall portion of the viscous fluid-filled damper of the present invention, it can be configured as a cylindrical molded body that is fitted into an annular recess formed on the outer peripheral surface of the stirring tube portion. The cylindrical portion can be made difficult to deform. In this case, the cylindrical molded body may be made of a material having a hardness capable of suppressing deformation of the stirring cylinder portion, and a material such as a synthetic resin or a metal can be used.

  In addition, the shape of the inner peripheral surface of the stirring cylinder portion in the viscous fluid-filled damper of the present invention as described above does not necessarily have to be a relative shape to the shape of the outer peripheral surface of the mounting shaft. There is no corresponding portion (engagement concave part of the conventional example described above) with the engagement head of the conventional example, and there may be a shape without unevenness in the longitudinal direction. In other words, the viscous fluid-filled damper according to the present invention is only required to be able to suppress deformation caused by expanding the stirring cylinder portion in the direction in which the retaining portion of the mounting shaft is pulled out by the hard wall portion. Therefore, if the retaining portion is formed on the mounting shaft, such an effect of the hard wall portion can be exhibited even if the inner peripheral surface of the stirring tube portion does not necessarily have a corresponding portion.

  In addition, the rubber-like elastic body used as the flexible membrane portion and the stirring cylinder portion in the viscous fluid-filled damper according to the present invention is not highly durable as it is very difficult to break or wear out. A soft rubber-like elastic body that is excellent in vibration damping effect due to elastic deformation is used. Such a rubber-like elastic body is JIS K 6253 type A and has a hardness of about 0 to 60.

  According to the viscous fluid-filled damper of the present invention, since the hard wall portion can exert a strong holding force with respect to the mounting shaft, even if the mounting shaft is largely displaced due to resonance or impact, the mounting shaft is difficult to come off.

  According to the viscous fluid-filled damper of the present invention, since the hard wall portion is formed also on the outer surface on the tip side of the stirring tube portion, the high vibration durability of the stirring tube portion can be exhibited. Even if the stirring cylinder part collides with the inner surface of the sealed container, it is difficult to break.

  Therefore, according to the viscous fluid-filled damper of the present invention described above, excellent vibration damping performance can be continuously obtained even when used in an environment where strong vibrations and impacts are applied, such as car audio devices and car navigation devices. It is possible to demonstrate.

  Embodiments of the present invention will be described below with reference to the drawings. In addition, about the member which is common in a prior art, and the structure which is common between embodiment, the same code | symbol is attached | subjected and duplication description is abbreviate | omitted.

First Embodiment [FIGS. 1 to 3] : A viscous fluid-filled damper 11 of this embodiment has a configuration in which a viscous fluid 3 is sealed in a sealed container 2 as shown in FIG. The sealed container 2 includes a peripheral wall portion 4 made of a hard resin such as polypropylene, a lid body 6, and a flexible film portion 5 made of a thermoplastic elastomer as a rubber-like elastic body.

  The flexible membrane portion 5 of this embodiment is formed with a thick opening side end portion 5a that is fixed to the peripheral wall portion 4, and secures a large fixing area with respect to the peripheral wall portion 4 and buckles the opening side end portion 5a. It is difficult to obtain the shape maintaining property of the entire flexible film portion 5. A lower standing wall 5b extends from the opening-side end 5a, and a lower lateral wall 5c extends radially inward from the upper end. The upper standing wall portion 5d extends again from the inner peripheral end of the lower horizontal wall portion 5c, and the upper horizontal wall portion 5e extends from the upper end thereof. Thus, by making the flexible film part 5 into a step shape, the effective length of the flexible film part 5 which is elastically deformed is increased, and the damping performance is enhanced. And the stirring cylinder part 12 is integrally formed in the inner peripheral end of the upper side wall part 5e.

  The stirring tube portion 12 of this embodiment has a bottomed cylindrical shape. The outer peripheral surface 13 has a shape with an equal diameter and no unevenness in the longitudinal direction. On the other hand, the insertion concave portion 14 includes, in order from the opening end side thereof, a columnar shaft portion 9b and a relative inner peripheral surface 14a of the mounting shaft 9, and an engaging head as a “preventing portion” of the mounting shaft 9. 9a and an engagement recess 14b having a relative shape are formed. At the upper end of the engaging recess 14b, a locking receiving surface 14c is formed in which the stepped surface 9c of the engaging head 9a of the mounting shaft 9 abuts and locks in the pulling direction.

  And the hard wall part 15 which consists of hard resin, such as a polypropylene, is integrally embedded by the shaping | molding in the stirring cylinder part 12 of this form. As shown in FIG. 3, the hard wall portion 15 is formed in an endless annular shape, and the length along the axial direction thereof is substantially the depth of the locking recess 14b, that is, the axial direction of the engaging head 9a. It is about the same as the length along. The lower end of the hard wall portion 15 is located on the radial extension line of the aforementioned locking receiving surface 14c.

Next, the operation and effect of the hard wall portion 15 of this embodiment will be described. When the mechanical chassis 8 is greatly displaced due to resonance vibration or impact and the mounting shaft 9 is about to move in the pull-out direction as in FIG. The surface 14c is pressed in the pulling direction, and the inner peripheral surface 14a is pushed outward in the radial direction.

  However, the stirrer tube portion 12 is formed with a hard wall portion 15, and the lower end of the stirrer tube portion 12 is positioned substantially at an extension of the locking receiving surface 14 c of the mounting shaft 9. Further, the thickness of the thermoplastic elastomer forming the stirring tube portion 12 in the radially inner portion of the hard wall portion 15 is thin. Therefore, in the portion where the hard wall portion 15 exists, elastic deformation outward in the radial direction is suppressed, and it is difficult for the engaging head portion 9a of the mounting shaft 9 to spread the inner peripheral surface 14a of the stirring tube portion 12. It becomes. In this embodiment, it is possible to suppress the detachment from the engagement recess 14b, which is the normal insertion position of the engagement head 9a, in this way.

Second Embodiment [FIG. 4] This embodiment is different from the first embodiment in the configuration of the hard wall portion 22 in the stirring tube portion 21. That is, the hard wall portion 22 of this embodiment is formed up to the upper end side of the stirring tube portion 21. Therefore, it becomes possible to make it difficult to be deformed over the substantially entire length of the inner peripheral surface 14 a of the plug-in cylinder portion 14, and a stronger holding force for the mounting shaft 9 can be exhibited. Further, a peripheral wall 23 having a diameter smaller than that of the stirring tube portion 21 is formed at the upper end of the hard wall portion 22. Therefore, a large contact area of the hard wall portion 22 with respect to the stirring cylinder portion 21 can be secured, and a strong fixing force can be exhibited.

Third Embodiment [FIG. 5] : This embodiment is different from the first embodiment in the configuration of the hard wall portion 32 in the stirring tube portion 31. That is, the hard wall portion 32 of this embodiment is formed in a thin layer covering the entire outer surface of the stirring tube portion 31. As a result, it becomes possible to make it difficult to deform the stirring cylinder portion 31 as a whole, and to exert a strong holding force with respect to the mounting shaft (not shown). Further, even if the stirring cylinder part 31 receives resonance or impact and collides with the lid 6 or the peripheral wall part 4 made of hard resin, the outer surface of the stirring cylinder part 31 is covered with the hard wall part 32. Therefore, damage to the stirring cylinder portion 31 can be suppressed. In addition, in the insertion recessed part 14 of this form, the engagement recessed part 14d is made into the substantially arrow-head shape, and the attachment shaft of a relative shape is inserted in this.

Fourth Embodiment [FIG. 6] : This embodiment is a modification of the third embodiment. That is, in the third embodiment, the lower end of the stirring tube portion 31 including the hard wall portion 32 is formed into a cornered shape, but in this embodiment, the stirring tube portion 41 is formed into a rounded shape including the hard wall portion 42. It is a thing. Further, the engagement recess 14e of the insertion recess 14 of the present embodiment has a substantially spherical shape, and an attachment shaft (not shown) having an engagement head of a shape relative to this is inserted.

  By the way, in the stirring cylinder part 41 of this form, the surface direction is lacking the latching receiving surface 14c along the radial direction of the stirring cylinder parts 12, 21, and 31 as shown in 1st-3rd embodiment. However, the engaging head portion of the mounting shaft inserted into the engaging concave portion 14e is pressed so as to push the inner peripheral surface 14a in the pulling direction to deform the stirring tube portion 41, and the stirring tube portion 41 is deformed. Is the same as that of the above-mentioned embodiment. Therefore, even in the present embodiment in which the insertion recess 14 is formed with the engagement recess 14e having a substantially spherical shape and lacks the locking receiving surface 14c, it is possible to make it difficult for the mounting shaft to come off. Further, even if the stirring tube portion 41 receives resonance or impact and collides with the lid 6 or the peripheral wall portion 4 made of hard resin, the outer surface of the stirring tube portion 41 is covered with the hard wall portion 42. Therefore, damage can be suppressed.

Fifth Embodiment [FIGS. 7 and 8] : This embodiment is different from the first embodiment in the configuration of the hard wall portion 52 of the stirring tube portion 51. As shown in FIG. 8, the hard wall portion 52 is formed to have a cylindrical base portion 52a and four protruding piece portions 52b formed in a cantilever shape along the axial direction from the cylindrical base portion 52a. Has been. The projecting piece 52b is formed thick, and the thermoplastic elastomer in the radially inner portion is thin. Therefore, in this embodiment, even if the mounting shaft 9 is pressed in the pulling direction, the thick protruding piece 52b is strongly suppressed so that the stirring cylinder 51 does not elastically deform radially outward. Become. If the protruding piece 52b is formed thick as in the present embodiment, the insertion of the mounting shaft 9 becomes very hard and there is a problem that the mounting workability is slightly inferior. In this embodiment, in order to eliminate this problem, as shown in FIG. 8, a split groove 52 c is provided that insulates adjacent projecting piece parts 52 b, and is filled with a thermoplastic elastomer forming the stirring cylinder part 51. I am doing so. For this reason, since the thermoplastic elastomer filled in the split groove 52c is relatively easily deformed, the pressing force required for inserting the mounting shaft 9 can be slightly reduced so that the mounting workability is not impaired. Yes.

Sixth Embodiment [FIG. 9] : This embodiment is different from the first embodiment in that, as shown in FIG. 9A, the insertion concave portion 62 of the stirring cylinder portion 61 has a surface difference or unevenness in the depth direction. It is a point that has a flat surface shape without any gaps. When the mounting shaft 9 is inserted into the insertion recess 62, as shown in FIG. 9B, the bottom side of the stirring tube portion 61 is radially directed by the engagement head 9a having a larger diameter than the insertion recess 62. It will be installed in a state of being spread outward. When the mounting shaft 9 is pressed in the removal direction, the hard wall portion 15 suppresses the compressive deformation of the thermoplastic elastomer on the inside thereof in the radially outward direction. Similarly to the form, the elastic deformation of the stirring cylinder portion 61 in the radially outward direction is suppressed, and the attachment shaft 9 is difficult to come off. In this way, if the engagement head 9a is formed on the mounting shaft 9, in the viscous fluid-filled damper 11 of the present invention, an engagement recess having a relative shape is necessarily formed in the insertion recess of the stirring cylinder portion. The mounting shaft 9 can be made difficult to come off even in such a case.

Seventh Embodiment [FIG. 10] This embodiment is different from the first embodiment in that the hard wall portion 72 of the stirring tube portion 71 is formed on the upper end side, and in the depth direction of the insertion concave portion 14. An engaging recess 14f is formed at an intermediate position, and a lower inner peripheral surface 14g similar to the upper inner peripheral surface 14a is formed below the engaging concave portion 14f. Even if the stirring cylinder portion 71 has such a configuration, it is possible to make it difficult to remove the attachment shaft (not shown) as in the above-described embodiments.

Eighth Embodiment [FIG. 11] : This embodiment is different from the first embodiment in that the hard wall portion 82 of the stirring cylinder portion 81 is formed up to the distal end side of the stirring cylinder portion 81. Similarly to the first embodiment, the hard wall portion 82 of this embodiment is an endless ring and is integrally formed with a flexible membrane portion 83 made of a rubber-like elastic body by molding. With such a configuration, similarly to the first embodiment, even when resonance vibration or impact is applied, the mounting shaft 9 is difficult to come out, and the stirring cylinder 81 is greatly displaced to form the peripheral wall 84 and the lid 85 made of hard resin. Even if it collides, since the outer surface on the front end side of the stirring cylinder portion 81 is covered with the hard wall portion 82, the outflow of the viscous fluid 3 to the outside due to breakage can be suppressed.

  The high vibration durability of the stirring cylinder 81 is the same as that of the stirring cylinder 31 of the third embodiment and the stirring cylinder 41 of the fourth embodiment. It is formed as a thin layer that is thinner than the thickness of the rubber-like elastic body that constitutes the stirring tube portions 31 and 41. On the other hand, the hard wall portion 82 of this embodiment is thicker than the thickness of the rubber-like elastic body constituting the stirring tube portion 81 and is formed as a thick concave shape from the upper end side to the lower end side. . Therefore, compared with 3rd Embodiment and 4th Embodiment, the outstanding high vibration durability is exhibited.

Ninth Embodiment [FIG. 12] : This embodiment is a modification of the stirring cylinder portion 81 in the eighth embodiment. The difference from the stirring tube portion 81 of the eighth embodiment is that the upper end side of the hard wall portion 92 of the stirring tube portion 91 extends to a position close to the base end of the stirring tube portion 91 and the hard wall portion. The lower end of 92 is formed with a hole 93 that serves as an inlet for the rubber-like elastic body during molding. In this embodiment, in addition to the same operations and effects as in the eighth embodiment, the upper end side of the hard wall portion 92 extends to a position close to the base end of the stirring tube portion 91, so that the length of the stirring tube portion 91 is increased. There exists an advantage which can make it difficult to remove the attachment shaft 9 over a direction.

10th Embodiment [FIGS. 13-15] This form is a modification of the stirring cylinder part 81 in 8th Embodiment. The hard wall portion 102 provided in the stirring tube portion 101 of the present embodiment has a bottomed cylindrical shape and is formed as a length over the entire length of the stirring tube portion 101. The hard wall portion 102 is formed with a small diameter portion 103 and two slits 104 along the longitudinal direction of the stirring tube portion 101. Each slit 104 is formed at a symmetrical position about the axis of the stirring tube portion 101. Each slit 104 is formed from the upper end of the hard wall portion 102 to a position facing the inner bottom of the insertion recess 105 of the stirring tube portion 101. Then, a cylindrical soft covering portion 106 integral with the rubber-like elastic body of the flexible film portion 83 is formed so as to cover the entire circumference of the small diameter portion 103 while filling each slit 104. The stirring tube portion 101 of this embodiment is composed of a hard wall portion 102 and a soft covering portion 106.

  In the stirring cylinder portion 101 of the present embodiment as described above, the mounting shaft 9 is in contact with the inner peripheral surface of the hard wall portion 102, so that it rubs against the rubber-like elastic body constituting the stirring cylinder portion 101, that is, the soft covering portion 106. It can be eliminated at all. In this regard, the portion of the soft covering portion 106 that closes the slit 104 may come into contact with the mounting shaft 9. However, as long as the hard wall portion 102 is not worn away, the portion will not rub against the mounting shaft 9 and will not be worn. Therefore, as compared with the above-described embodiments, there is an advantage that the vibration durability of the stirring tube portion 101 can be remarkably improved because the rubber-like elastic body constituting the stirring tube portion 101 is hardly worn. is there.

  Even if the inner peripheral surface of the hard wall portion 102 is opposed to the outer peripheral surface of the mounting shaft 9, the mounting shaft 9 is fixed to the stirring cylinder portion 101 if the mounting shaft 9 is pushed so as to widen the slit 104. can do. In addition, the slit 104 is narrow and narrow, and is prevented from being pulled out unless a large force is applied thereto, so that a high holding force can be exhibited as in the above-described embodiments.

  13 and 14 show an example in which the slit 104 is formed up to the position facing the inner bottom of the insertion recess 105, but in order to further increase the holding force of the mounting shaft 9, for example, as shown in FIG. The shallow slit 107 up to the vicinity of the lower end position of the small diameter portion 103 may be used.

Eleventh Embodiment [FIG. 16] : This embodiment differs from the above embodiments in that an annular hard ring 112 as a “hard wall portion” is formed in an annular recess 111a formed on the outer peripheral surface of the stirring tube portion 111. Is configured to be fitted. Specifically, before filling the viscous fluid 3, the stirrer tube portion 111 is crushed so that the hard ring 112 is fitted into the annular recess 111a. Then, after that, the viscous fluid 3 is filled, and the lid body 6 is fixed to the peripheral wall portion 4 as in the first embodiment. Even if the stirring cylinder portion 111 has such a configuration, it is possible to make it difficult to remove the attachment shaft (not shown) as in the above-described embodiments.

  Hereinafter, based on an Example, the effect | action and effect of the viscous fluid enclosure damper by this invention are demonstrated more concretely.

The viscous fluid-filled damper used as an example has the same structure as that of the aforementioned eighth embodiment. This viscous fluid-filled damper uses a thermoplastic styrenic elastomer having a hardness of 20 (JIS K6253 type A) as a rubber-like elastic body constituting the stirring cylinder portion (81) and the flexible membrane portion (83), and has a hard wall. Polypropylene resin was used as the hard resin constituting the portion (82), the peripheral wall portion (84), and the lid (85). The rubber-like elastic body part and the flexible film part (83) constituting the stirring cylinder part (81) are the peripheral wall part (84) and the hard wall part obtained by molding in advance in the cavity of the injection mold. After transferring (82), a thermoplastic styrene-based elastomer is injected and integrally molded. Thus three of the container obtained, the three types of silicone grease rotational viscosity 1.3m ² /s,1.7m ² /s,1.9m ² / s as the viscous fluid (3) were each filled, finally The lid part (85) was joined to the peripheral wall part (84) by ultrasonic fusion to obtain viscous fluid-filled dampers of Examples 1 to 3.

  On the other hand, as a comparative example, as shown in FIG. 17 and FIG. 18, the same as in Examples 1 to 3 except that the stirring cylinder part (81) was formed of a styrene thermoplastic elastomer. A viscous fluid-filled damper was obtained.

  The viscous fluid-filled dampers of Examples 1 to 3 and Comparative Examples 1 to 3 obtained as described above were subjected to performance tests on vibration damping performance, vibration durability, and mounting shaft holding force.

The test method for vibration damping performance is as follows. That is, a supported body having a mass of 300 g, which is assumed to be a mechanical chassis of a disk-shaped recording medium, is supported and suspended by four coil springs inside the casing, and four mounting shafts protrude downward on the supported body. The mounting shaft was inserted into the stirring cylinder portion of the viscous fluid-filled damper and held. The viscous fluid-filled damper was fixed to the bottom plate of the casing serving as a support, and the bottom plate of the casing was fixed on the vibration table. Then, the casing fixed to the vibration table is vibrated in the vertical direction at a constant acceleration of 9.8 m / s ² in the frequency range of 8 to 200 Hz, and the vibration transmissibility between the casing and the supported body is measured. The vibration damping performance was evaluated. The resonance magnification was obtained by measuring the acceleration a _{2 of the} supported body with respect to the acceleration a ₁ of the housing at the resonance frequency and converting it by a relational expression of ₂₀ Log (a ₂ / a ₁ ).

The vibration durability test method was performed by changing the vibration damping performance test and the vibration condition described above. That is, the casing fixed on the vibration table is vibrated in the vertical direction at a constant acceleration of 29.4 m / s ² in the frequency range of 10 to 50 Hz, and the viscous fluid leaks out from the viscous fluid-filled damper. The time until was measured.

  As a test method for the holding force of the mounting shaft, the maximum stress was measured when the mounting shaft was pulled upward at a speed of 500 mm / min with the viscous fluid-filled damper fixed to the bottom plate of the casing.

Table 1 shows the results of the above tests performed on viscous fluid-filled dampers for the examples and comparative examples. From these results, Examples 1 to 3 exhibit higher vibration damping performance than conventional Comparative Examples 1 to 3, but the stirring cylinder portion is less likely to be damaged and the outflow of viscous fluid can be suppressed. It can be seen that the excellent performance that it is difficult to come out can be demonstrated.

Sectional drawing which follows the FIG. 2SA-SA line of the viscous fluid enclosure damper by 1st Embodiment. The top view of the viscous fluid enclosure damper of FIG. The expansion perspective view of the stirring cylinder part of the viscous fluid enclosure damper of FIG. The expanded sectional view of the stirring cylinder part of the viscous fluid enclosure damper by 2nd Embodiment. The expanded sectional view of the stirring cylinder part of the viscous fluid enclosure damper by 3rd Embodiment. The expanded sectional view of the stirring cylinder part of the viscous fluid enclosure damper by 4th Embodiment. The expanded sectional view of the stirring cylinder part of the viscous fluid enclosure damper by 5th Embodiment. The expansion perspective view of the hard wall part shown in FIG. The expanded sectional view of the stirring cylinder part of the viscous fluid enclosure damper by 6th Embodiment. The expanded sectional view of the stirring cylinder part of the viscous fluid enclosure damper by 7th Embodiment. It is a figure which shows the viscous fluid enclosure damper by 8th Embodiment, and a fraction (A) is a sectional view (B) SB-SB sectional view, A sectional view (B) is a top view. It is a figure which shows the viscous fluid enclosure damper by 9th Embodiment, and is sectional drawing equivalent to FIG. 11 (B) SB-SB line. It is a figure which shows the viscous fluid enclosure damper by 10th Embodiment, and is sectional drawing equivalent to FIG. 11 (B) SB-SB line. The expanded sectional view which follows the SC-SC line of FIG. The expanded sectional view which shows the modification of the stirring cylinder part shown in FIG. The disassembled perspective view of the stirring cylinder part of the viscous fluid enclosure damper by 11th Embodiment. The schematic diagram explaining the use condition of the viscous fluid enclosure damper by a prior art example. The expanded sectional view of the stirring cylinder part of the viscous fluid enclosure damper of FIG.

Explanation of symbols

2 Sealed Container 3 Viscous Fluid 9 Mounting Shaft 11 Viscous Fluid Enclosed Damper (First Embodiment)
DESCRIPTION OF SYMBOLS 12 Stirring cylinder part 14 Insertion recessed part 14a Inner peripheral surface 14b Engaging recessed part 14c Locking receiving surface 21 Stirring cylinder part (2nd Embodiment)
22 hard wall part 23 peripheral wall 31 stirring cylinder part (3rd Embodiment)
32 Hard wall part 14d Locking receiving surface 41 Stirring cylinder part (4th Embodiment)
42 Hard wall portion 14e Locking receiving surface 51 Stirring tube portion (fifth embodiment)
52 Hard wall part 52a Base part 52b Projection piece part 61 Stirring cylinder part (6th Embodiment)
62 Insertion recessed part 71 Stirring cylinder part (7th Embodiment)
72 Hard wall part 14f Engagement recessed part 14g Lower inner peripheral surface 81 Stirring cylinder part (8th Embodiment)
82 Hard wall part 83 Flexible film part 84 Peripheral wall part 85 Cover body 91 Stirring cylinder part (9th Embodiment)
92 Hard wall part 93 Hole 101 Stirring cylinder part (10th Embodiment)
102 Hard wall part 103 Small diameter part 104 Slit 105 Insertion recessed part 106 Soft coating | coated part 107 Slit 111 Stirring cylinder part (11th Embodiment)
111a annular recess 112 hard ring (hard wall)

Claims (11)

A sealed container and a viscous fluid sealed in the sealed container,
In the sealed container,
A mounting shaft formed with a retaining portion that bulges outward in the radial direction on a shaft portion protruding from either a mechanical chassis having a reproducing device for a disk-shaped recording medium or a housing housing the mechanical chassis, An agitating tube portion that holds and holds
In a viscous fluid-filled damper provided with a flexible membrane portion made of a rubber-like elastic body that supports the stirring cylinder portion in a floating state,
The stirring tube portion is formed of a rubber-like elastic body that is continuous with the flexible membrane portion, and at least the portion of the stirring tube portion corresponding to the shaft portion side from the boundary between the shaft portion of the mounting shaft and the retaining portion is removed. Provided with a hard wall portion that restricts movement of the stopper portion in the pulling direction by suppressing deformation of the rubber-like elastic body in the radially outward direction, and the hard wall portion forms a stirring cylinder portion by molding A viscous fluid-filled damper, characterized in that it is a molded body fixed to a cylindrical elastic body . A sealed container and a viscous fluid sealed in the sealed container,
In the sealed container,
A mounting shaft formed with a retaining portion that bulges outward in the radial direction on a shaft portion protruding from either a mechanical chassis having a reproducing device for a disk-shaped recording medium or a housing housing the mechanical chassis, An agitating tube portion that holds and holds
In a viscous fluid-filled damper provided with a flexible membrane portion made of a rubber-like elastic body that supports the stirring cylinder portion in a floating state,
The stirring tube portion is formed of a rubber-like elastic body that is continuous with the flexible membrane portion, and at least the portion of the stirring tube portion corresponding to the shaft portion side from the boundary between the shaft portion of the mounting shaft and the retaining portion is removed. A hard wall is provided to restrict the movement of the stopper in the pulling direction by suppressing the outward deformation of the rubber-like elastic body in the radial direction, and the hard wall is formed also on the outer surface on the front end side of the stirring cylinder. and, and a rubber-like elastic material filling the pores is provided a hole at the lower end of the rigid wall portion, the viscous fluid-sealed damper, characterized in that the rubber-like elastic material is exposed to the outer surface of the agitation cylinder portion through the holes . A sealed container and a viscous fluid sealed in the sealed container,
In the sealed container,
A mounting shaft formed with a retaining portion that bulges outward in the radial direction on a shaft portion protruding from either a mechanical chassis provided with a reproducing apparatus for a disk-shaped recording medium or a housing that houses the mechanical chassis, An agitating tube portion that holds and holds
In a viscous fluid-filled damper provided with a flexible membrane portion made of a rubber-like elastic body that supports the stirring cylinder portion in a floating state,
The stirring tube portion is formed of a rubber-like elastic body continuous with the flexible membrane portion, and at least the portion of the stirring tube portion corresponding to the shaft portion side from the boundary between the shaft portion of the mounting shaft and the retaining portion is removed. the movement in the dropout direction of the retaining portion is provided rigid wall portion for regulating by suppressing deformation in the radial direction outwardly of the rubber-like elastic material, intermittently the rigid wall portion in the circumferential direction of the agitation cylinder portion It is with the cylindrical base portion and the viscous fluid-sealed damper, characterized in that a shape having a plurality of protruding portions formed in a cantilever shape along its axial direction from the cylindrical base portion. The viscous fluid-filled damper according to claim 1 or 2 , wherein the hard wall portion is formed in an endless annular shape over the entire circumference of the stirring cylinder portion. The viscous fluid-filled damper according to any one of claims 1 to 4 , wherein the hard wall portion is formed up to an upper end side of the stirring cylinder portion. The viscous fluid-filled damper according to any one of claims 1 to 5 , wherein the hard wall portion is formed also on the outer surface on the front end side of the stirring cylinder portion. The viscous fluid-filled damper according to any one of claims 1 to 6 , wherein the hard wall portion is formed so as to cover the entire outer surface of the stirring cylinder portion. The viscous fluid-filled damper according to any one of claims 1 to 3, 5, or 6 , wherein the hard wall portion is formed intermittently in the circumferential direction of the stirring tube portion. The viscous fluid-filled damper according to claim 8 , wherein the hard wall portion is formed in an annular shape having slits along the axial direction and spaced apart in the circumferential direction.   The viscous fluid-filled damper according to any one of claims 1 to 9, wherein the insertion concave portion of the stirring cylinder portion is flush with the depth direction. 4. The viscous fluid-filled damper according to claim 2 , wherein the hard wall portion is a molded body fixed to a rubber-like elastic body constituting the stirring cylinder portion by molding.

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