JP2005180611A - Magnetic field controlling viscous fluid-sealed damper and method of controlling the same - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To control the viscosity of a viscous fluid by acting external magnetic field to magnetic particles according to an actual temperature by eliminating the separation of the actual temperature of the viscous fluid in which the magnetic particles are mixed from the measured temperature of a temperature sensor in a magnetic field controlling viscous fluid sealed-damper. <P>SOLUTION: The temperature sensing part 9b of the temperature sensor 9 is brought into direct contact with the viscous fluid 3 in the sealed container 2 of the magnetic field controlling viscous fluid sealed-damper 1. The portion of the sealed container 2 where the conduction part 9a of the temperature sensor 9 extending from the temperature sensing part 9b thereof to the outside is passed is sealed liquidtight so that the viscous fluid 3 does not leak to the outside to prevent vibration damping property from being impaired. <P>COPYRIGHT: (C)2005,JPO&NCIPI

Description

  The present invention relates to a viscous fluid-filled damper that attenuates vibration of a disk device that reads data from a disk-shaped recording medium by a non-contact reading method, such as an in-vehicle CD player, and more particularly to a viscous fluid containing magnetic particles. The present invention relates to a magnetic field control viscous fluid-filled damper capable of controlling damping characteristics by controlling the viscosity of a viscous fluid in accordance with the density of magnetic particles along a magnetic field line by applying an external magnetic field in a variable manner.

In the disk device as described above, since a reproduction error may occur due to internal vibration or external vibration, a vibration isolator is generally interposed between the housing and the disk device. As this vibration isolator, one end side opening of a cylindrical peripheral wall portion made of a hard resin such as polypropylene is sealed with a rubber elastic film such as a thermoplastic elastomer, and the opening end on the other end side of the container body There is known a viscous fluid-sealed damper in which a hermetic container is closed with a lid made of a hard resin, and a viscous fluid such as silicone oil is sealed in the hermetic container (Patent Document 1).
JP 2000-18311 A

By the way, it is known that the viscous fluid sealed in the viscous fluid-filled damper has temperature dependency in viscosity. That is, when the temperature of the viscous fluid becomes low, the viscosity increases, and when the temperature becomes high, the viscosity decreases. Therefore, there is a problem that the damping characteristic exhibited by the viscous fluid also changes depending on the temperature. Therefore, a magnetic field control viscous fluid-filled damper is known in which a magnetic fluid is used as the viscous fluid of the viscous fluid-filled damper, and the viscosity of the magnetic fluid can be adjusted by applying an external magnetic field that is variable in strength. For this damper, the internal temperature of the housing that houses the disk device is measured by a temperature sensor, and an external magnetic field is applied to the magnetic fluid accordingly, thereby controlling the viscosity of the viscous fluid to a constant level. A technique for trying to reduce the influence of the dependency on the attenuation characteristic has been proposed (Patent Document 2).
Japanese Utility Model Publication No. 7-19645

  According to this prior art, an external magnetic field is applied in accordance with a change in the internal temperature of the housing, so that it is expected that the temperature dependence of the magnetic fluid can be reduced. However, since the action of the external magnetic field is controlled based on the internal temperature detected by the temperature sensor located away from the damper, it may deviate from the actual magnetic fluid temperature. Attenuation performance may not be obtained.

  The present invention is based on the above-described technology, and its purpose is to eliminate the deviation between the temperature measured by the temperature sensor and the actual temperature of the viscous fluid, and to match the actual temperature of the viscous fluid. It is to be able to control and to reduce the influence of temperature dependence.

  In order to achieve the above object, the present invention provides a hermetically sealed container including a container body having an annular opening end and a lid that closes the opening end, in which a viscous fluid containing magnetic particles is sealed in a liquid-tight manner. There is provided a temperature sensor having a temperature sensing unit in contact with the viscous fluid inside the sealed container for the magnetically controlled viscous fluid-filled damper in which the viscosity of the viscous fluid changes by applying an external magnetic field to the magnetic particles. It is characterized by that. In the present invention, since the temperature sensing part of the temperature sensor is in direct contact with the viscous fluid inside the sealed container, the measurement temperature does not deviate from the actual temperature, and the measurement accuracy of the temperature of the viscous fluid can be increased. Therefore, even if the temperature of the viscous fluid changes, magnetic field control that appropriately applies a variable magnetic field suitable for the temperature of the viscous fluid is possible so that the apparent viscosity of the viscous fluid does not substantially change. The temperature dependence of the fluid can be reduced.

  In the damper, the temperature sensor has a conductive part extending from the temperature sensing part to the outside of the sealed container, and the sealed container includes the introduction part of the conductive part, the introduction part, and the introduction part. And a sealing member that liquid-tightly closes the gap with the conductive portion. In the present invention, leakage of viscous fluid to the outside of the sealed container is prevented by the sealing member, and vibration damping properties are not impaired.

  According to the present invention, in the damper, the introduction portion of the sealed container is a hole-shaped portion, and the sealing member is a rubber-like elastic body that liquid-tightly closes a gap between the conductive portion of the temperature sensor and the hole-shaped portion. It is comprised as an elastic seal piece. In the present invention, by the elastic deformation following the shape of the elastic seal piece, the gap between the conductive portion of the temperature sensor and the hole-like portion is sealed in a liquid-tight state in a pressed state, thereby preventing leakage of viscous fluid. .

  In the damper having a hole-shaped portion, the hole-shaped portion of the sealed container is a mounting groove directed to at least one of the boundary between the opening end of the container main body and the lid, and the elastic seal piece is attached to the damper. It is configured to be provided so as to face each other along the longitudinal direction of the mounting groove. In the present invention, leakage of viscous fluid can be prevented by exhibiting liquid-tightness due to the close contact of the elastic seal piece along the longitudinal direction of the mounting groove which is a hole-like portion.

  In the damper according to the present invention, the introduction portion of the sealed container is a hole-shaped portion, and the sealing member is configured as a cured resin body that is liquid-tightly fixed to the conductive portion of the temperature sensor and the hole-shaped portion. The In the present invention, the resin cured body as a sealing member is liquid-tightly fixed to the hole portion and the introduction portion of the temperature sensor, thereby preventing the leakage of viscous fluid and the temperature sensor to the hole portion. Can be fixed at a predetermined position.

  According to the present invention, the damper having a cured resin body as a sealing member is configured such that the cured resin body is filled and cured with a liquid resin in a gap between the conductive portion of the temperature sensor and the hole-shaped portion. In the present invention, since the liquid resin enters the gap between the hole-shaped portion and the conductive portion and is cured, leakage of the viscous fluid is reliably prevented.

  The present invention is configured as a resin molded body in which the resin cured body is integrally molded by mold molding so as to cover the conductive portion of the temperature sensor with respect to the damper having the cured resin body as a sealing member. In the present invention, since the resin molded body, which is a cured resin body, is integrally molded by molding with respect to the conductive portion of the temperature sensor, leakage of viscous fluid is reliably prevented.

  The present invention is configured such that the damper having a cured resin body as a sealing member is provided with an ultrasonic fusion bonding portion for fixing the cured resin body that is the sealing member and the hole portion of the sealed container. In the present invention, since the cured resin body and the hole-shaped part of the sealed container are integrated by the ultrasonic fusion part, leakage of the viscous fluid is surely prevented. In this case, the ultrasonic fusion part can be configured to be formed at the same time by ultrasonic fusion when the lid is fixed to one end opening of the container body. According to this, both the one-end opening of the container main body and the lid and the adhesion between the cured resin body and the hole-like portion can be completed in a single ultrasonic fusion process. Efficiency can be improved.

  In the damper, the temperature sensor has a conductive portion extending from the temperature sensing portion to the outside of the sealed container, and the conductive material of the temperature sensor is molded into either the container body or the lid of the sealed container. It is configured with the part embedded in one piece. In the present invention, the container body and the lid body are resin molded bodies in which the conductive portion of the temperature sensor is embedded, for example, by mold molding such as insert molding. Therefore, the temperature sensor is firmly attached to the container body and lid body with mass production efficiency. It can be fixed and integrated, and the viscous fluid can be reliably prevented from leaking.

  The present invention forms either one of an annular convex part or an annular concave part that engages with each other along the circumferential direction of the opening end of the container main body, and the lid is provided with either one of the above-mentioned dampers. Configured. In the present invention, the boundary surface between the open end of the container main body and the lid body is an uneven surface in which the annular protrusion and the annular recess are interleaved with each other, and the leakage of viscous fluid is reliably prevented.

  In order to achieve the above object, the present invention provides a magnetic field control viscous fluid sealing damper that controls the viscosity of a viscous fluid by applying an external magnetic field to the viscous fluid containing magnetic particles sealed in a sealed container. Regarding the control method, a temperature sensor in which the temperature sensing unit is in direct contact with the viscous fluid is installed in the sealed container of the magnetic field control viscous fluid-filled damper, and the viscous fluid is changed according to the direct temperature of the viscous fluid detected by the temperature sensor. On the other hand, it is characterized in that the external magnetic field is variably changed to control the viscosity of the viscous fluid.

  In the present invention, since the temperature sensing unit of the temperature sensor is in direct contact with the viscous fluid inside the sealed container, the temperature measurement accuracy of the viscous fluid can be increased. Therefore, even if the temperature of the viscous fluid changes, the magnetic field control that appropriately applies a variable magnetic field suitable for the temperature of the viscous fluid is possible so that the apparent viscosity of the viscous fluid does not substantially change. The temperature dependence of the fluid can be reliably reduced. Regarding this control method, there is a method of causing the external magnetic field to be variably changed with respect to the viscous fluid, such as a method of bringing the external magnetic field close to the magnetic field control viscous fluid-filled damper, which is proposed by the applicant of the present application. The method described in JP-A-2003-49895 can be used in the present invention. As another method, there is a method of variably blocking an external magnetic field acting on a magnetic field control viscous fluid-filled damper, which is configured as described below.

  According to the present invention, in the control method, the magnetic field control viscous fluid-filled damper is configured according to any one of the present inventions. According to this, the operation and effect of each magnetic field control viscous fluid-filled damper of the present invention described above is also exhibited.

  The present invention includes a magnetic field forming member that forms a transverse magnetic field in a hermetically sealed container of a magnetic field control viscous fluid-filled damper and a magnetic shield member, and directly controls the viscous fluid detected by the temperature sensor. The strength of the transverse magnetic field applied to the viscous fluid is determined according to the temperature, and at least one of the magnetic field forming member and the magnetic shield member is driven according to the strength, and the magnetic shield member blocks the transverse magnetic field. Thus, an external magnetic field that is variable in strength is applied to the viscous fluid.

  In the present invention, a transverse magnetic field is formed in the sealed container, and a strong magnetic field that appears as parallel and high-density magnetic field lines can be directly and uniformly applied to magnetic particles in the viscous fluid. In addition, since the magnetic field can be sufficiently applied, not only the binary viscosity fluid viscosity control by switching between the magnetic field state and the no magnetic field state, but also variable by analog control that gradually increases or decreases the magnetic field. Viscosity control is also possible. In order to perform such variable viscosity control, the strength of the transverse magnetic field applied to the viscous fluid is obtained according to the direct temperature of the viscous fluid detected by the temperature sensor, and according to the strength. It is only necessary to drive at least one of the magnetic field forming member and the magnetic shield member and block the transverse magnetic field in whole or in part by the magnetic shield member. Therefore, it is possible to instantaneously switch between the magnetic field state and the non-magnetic field state by a simple method of adjusting the driving amount, and it is easy to perform the switching stepwise. In this case, the drive of the magnetic field forming member or the magnetic shield member can be configured in various forms. For example, either the magnetic field forming member or the magnetic shield member can be rotated relative to the central axis of the damper so that the transverse magnetic field is blocked by the magnetic shield member. Further, the magnetic field forming member and the magnetic shield member are configured to be laterally slid in a direction orthogonal to the central axis of the damper, and when the magnetic field forming member and the magnetic shield member are at the opposing positions, the transverse magnetic field is the magnetic shield member. When the magnetic field forming member and the magnetic shield member are in a slide position separated by a lateral slide, the transverse magnetic field is not blocked by the magnetic shield member and the damper is not blocked by the magnetic fluid. It is also possible to drive such that it extends. Furthermore, a magnetic field forming member such as a magnet is disposed outside the outer peripheral surface of the sealed container enclosing the viscous fluid, and a plurality of shield walls are provided with a predetermined interval between the magnetic field forming member and the sealed container. A magnetic shield member having an outer magnetic shield wall and an inner magnetic shield wall arranged in a row may be provided, and the outer magnetic shield wall and the inner magnetic shield wall may be driven to slide relative to each other. In this configuration, due to the relative sliding, the transverse magnetic field of the magnetic field forming member reaches the viscous fluid when the space where the outer magnetic shield wall and the inner magnetic shield wall overlap each other is opened. On the other hand, due to the relative slide, when the gap between the shield walls does not overlap, the transverse magnetic field of the magnetic field forming member is blocked by the shield wall of the outer magnetic shield wall and the inner magnetic shield wall. .

  According to the magnetic field control viscous fluid encapsulated damper and the magnetic field control viscous fluid encapsulated damper control method of the present invention, the measurement accuracy of the viscous fluid is improved by direct temperature measurement, and the temperature dependence of the viscous fluid is improved by more appropriate magnetic field control. Therefore, it is possible to reliably attenuate the vibration of the disk device that reads data from a disk-shaped recording medium such as an in-vehicle CD player by a non-contact reading method regardless of the environmental temperature. Contributes to increased added value of equipment.

  Hereinafter, an example of an embodiment of the present invention will be described with reference to the drawings.

First Embodiment of Magnetic Field Control Viscous Fluid Enclosed Damper [FIGS. 1 to 5] ; A magnetic field control viscous fluid encapsulated damper 1 shown in FIG. 1 is a liquid container containing a viscous fluid 3 containing magnetic particles (not shown). Constructed by tightly enclosing.

  The sealed container 2 includes a container body 4 and a lid 5. Among these, the container body 4 includes a cylindrical peripheral wall portion 6 made of a hard resin such as polypropylene. A floating support portion 7 is provided at an upper end portion of the peripheral wall portion 6, and a stirring cylinder portion 8 that protrudes toward the inside of the closed container 2 (container body 4) is formed at the top portion. The floating support portion 7 and the stirring cylinder portion 8 are integrally formed by molding a rubber-like elastic body such as a thermoplastic elastomer. On the other hand, an outward flange 6 a is formed in an annular shape at the lower end of the peripheral wall 6. The lid 5 is also made of a hard resin such as polypropylene, and has an annular protrusion 5a as an “annular protrusion”. An annular recess 6c that engages with the annular protrusion 5a is formed at the inner peripheral portion of the outward flange 6a, that is, the lower end of the inner peripheral surface 6b of the peripheral wall 6 so as to correspond to the annular protrusion 5a.

  The circumferential wall 6 is formed with a groove 6d along the radial direction, and an elastic seal piece 6e made of a rubber-like elastic body such as a thermoplastic elastomer is formed inside the groove 6d. The elastic seal piece 6e is integrally formed simultaneously with the molding of the floating support portion 7 and the stirring tube portion 8 with respect to the peripheral wall portion 6. As shown in FIG. 2, the elastic seal piece 6e is formed over the outward flange 6a and the annular recess 6c. Further, the elastic seal piece 6e is formed with a curved contact surface 6f having a circular arc shape along the outer peripheral surface shape of the conductive portion 9a of the thermocouple 9 as a "temperature sensor". The conductive portion 9a of the thermocouple 9 is connected to a controller that performs control to apply an external magnetic field that is variable in strength to the magnetic field control viscous fluid-filled damper 1. On the other hand, the lid 5 is formed with a projection 5b that engages with the groove 6d of the peripheral wall 6, and the projection 5b is formed with an attachment groove 5c that accommodates the elastic seal piece 6e and the conductive portion 9a. Has been.

  Therefore, as shown in FIG. 3, when the lid 5 is fixed to the peripheral wall 6 by ultrasonic fusion or the like, the annular protrusion 5 a of the lid 5 is fitted into the annular recess 6 c of the peripheral wall 6, and the groove portion of the peripheral wall 6. The protrusion 5b of the lid 5 is fitted into 6d, and the curved contact surface 6f of the elastic seal piece 6e in the groove 6d of the peripheral wall 6 is elastically in contact with the outer peripheral surface of the conductive portion 9a. 5c. As described above, in this embodiment, the viscous fluid 3 is prevented from leaking due to the concave / convex boundary surface due to the concave / convex engagement between the annular recess 6c and the annular protrusion 5a, and the pressing contact of the elastic seal piece 6e over the longitudinal direction of the conductive portion 9a. As a result, the inside of the mounting groove 5c is sealed in a liquid-tight manner. Therefore, the viscous fluid 3 remains liquid-tightly sealed inside the sealed container 2 and does not leak to the outside.

  And in the magnetic field control viscous fluid enclosure damper 1 of this form, tip part 9b as a "temperature sensing part" in thermocouple 9 will be located inside sealed container 2, and will contact with fluid 3 directly. Therefore, it is possible to increase the measurement accuracy of the temperature of the viscous fluid 3, and even if the temperature of the viscous fluid 3 changes, the temperature of the viscous fluid 3 is set so that the apparent viscosity of the viscous fluid 3 does not substantially change. Magnetic field control that appropriately applies a suitable variable magnetic field is possible, and the temperature dependence of the viscous fluid 3 can be reduced.

  The viscous fluid 3 sealed in the closed container 2 as described above is a silicone oil system such as dimethyl silicone oil, methyl phenyl silicone oil, methyl hydrogen silicone oil, or fluorine-modified silicone oil, mineral oil such as paraffin oil, or rapeseed oil. For example, vegetable oils such as polybutene, low molecular weight liquid polymers such as polybutene, phthalates, and aqueous solutions with adjusted viscosity are used. Among these, a silicone oil type that has a small viscosity change with respect to fluctuations in the ambient temperature of use is preferable.

  As magnetic particles (not shown) to be mixed with the viscous fluid 3, particles such as iron, nickel, carbon steel, silicon ore, alnico, Ferrox Dewar, ferrite, cobalt, permalloy can be used. Among them, a ferromagnetic particle having a high magnetic susceptibility such as soft ferrite powder that is not coercive or has little coercivity is preferable for increasing the response speed of viscosity change. The surface of the magnetic particles may be treated with a surface treatment agent such as a silane coupling agent.

  The viscous fluid 3 may be further mixed with a dispersion carrier that suppresses the sedimentation of the magnetic particles and maintains the dispersion state. Any dispersion carrier that does not react or dissolve in the viscous fluid 3 can be used. For example, polymethylsilsesquioxane powder, dry silica particles, glass beads, glass balloons, and their surface-treated products can be used. These may be used alone or in combination. In particular, it is preferable to use silicone resin powder that has a very high vibration damping effect due to viscosity, or wet silica that suppresses the viscosity change due to the temperature of the viscous fluid 3.

  The ratio of the viscous fluid 3, the magnetic particles and the dispersion carrier is 5 to 65% by volume of the magnetic particles and 5 to 65% by volume of the dispersion carrier with respect to the viscous fluid 3, and the total amount of the magnetic particles and the dispersion carrier is It is preferable that the viscosity fluid 3 is mixed so as to be in the range of 10 to 70% by volume. According to this, since it is possible to superimpose both moderate fluidity of the viscous fluid 3 and uniform dispersion of the magnetic particles by the dispersion carrier, an excellent vibration damping effect by viscoelasticity control can be exhibited. It is.

  The magnetic field control viscous fluid-filled damper 1 of the first embodiment as described above can be modified as shown in FIGS. 4 and 5, for example. In this example, as shown in FIG. 4, a resin layer 9 c covering the outer periphery is formed on the conductive portion 9 a of the thermocouple 9. The conductive portion 9a is formed by covering two conductive wires connected by the tip portion 9a, and the resin layer 9c is formed so as to cover it. And the groove part 6g which lacks the elastic seal pieces 6e as mentioned above is formed in the surrounding wall part 6. As shown in FIG. The protrusion 5b of the lid 5 facing the groove 6g is the same as described above.

  In such a configuration, when the peripheral wall portion 6 and the lid 5 are aligned, the protruding portion 5 b of the lid 5 is fitted into the groove portion 6 g of the peripheral wall portion 6. In this state, a gap exists around the resin layer 9c of the conductive portion 9a. Then, the outward flange 6a of the peripheral wall 6 and the lid 5 are ultrasonically fused. Then, by this ultrasonic fusion, the resin layer 9c is melted or softened, and the melted resin is filled in the gap existing between the groove 6g and the mounting groove 5c of the protrusion 5b and hardened. As a result, as shown in FIG. 5, a resin sealing portion 10 as a “resin cured body” is formed around the conductive portion 9a to seal the gap, and the resin sealing portion 10 and the groove 6g. And the ultrasonic fusion part 11 is formed in the boundary with the mounting groove 5c, and leakage of the viscous fluid 3 to the outside is prevented. Therefore, according to this example, since the resin sealing portion 10 is formed according to the shape of the gap, the sealed container 2 is reliably sealed. Further, since the ultrasonic fusion performed when the peripheral wall portion 6 and the lid 5 are fixed to each other is also used for forming the resin sealing portion 6h, the mass production efficiency can be improved.

  As another modification, for example, a liquid resin such as an adhesive is applied around the resin layer 9c shown in FIG. 4 and filled in a gap existing between the groove 6g and the mounting groove 5c of the protrusion 5b. It is also possible to cure and form the resin sealing portion 10 shown in FIG. In this sense, the resin layer 9c is not formed on the conductive portion 9a of the thermocouple 9, but a liquid resin such as an adhesive is directly applied to the outer periphery thereof, and the gap is filled and cured to obtain the resin shown in FIG. It is also possible to form the sealing portion 10. These “resin cured bodies” can also reliably seal the sealed container 2 and reliably prevent leakage of the viscous fluid 3.

Second Embodiment of Magnetic Field Controlled Viscous Fluid Enclosed Damper [FIGS. 6 to 8] ; Magnetic field controlled viscous fluid-enclosed damper 12 of this embodiment is a configuration of peripheral wall portion 13 and lid 14 of container body 4 constituting hermetic container 2. Is different from the first embodiment. In other words, in this embodiment, the conductive portion 15 a of the thermocouple 15 as a “temperature sensor” is embedded in the peripheral wall portion 13. Specifically, the peripheral wall portion 13 is made of a hard resin such as polypropylene, and the thermocouple 15 is set in the molding die and injection molded so that the conductive portion 15a is embedded in the peripheral wall portion 13 at the time of molding. . As a result, the conductive portion 15a is integrated with the peripheral wall portion 13 in an embedded state, and the inner peripheral surface of the peripheral wall portion 13 is connected to the two metal pieces forming the conductive portion 15a as a “temperature sensing portion”. The tip portion 15b protrudes. On the other hand, the conductive extension 15c connected to each of the two metal pieces extends to the outside on the outer peripheral surface of the peripheral wall 13. The conductive extension 15c is connected to a controller that performs control to give an external magnetic field that is variable in strength to the magnetic field control viscous fluid-filled damper 12.

  As a result, in this embodiment, the tip 15b of the thermocouple 15 is in direct contact with the viscous fluid 3. For this reason, it is possible to improve the measurement accuracy of the temperature of the viscous fluid 3, and even if the temperature of the viscous fluid 3 changes, the temperature of the viscous fluid 3 does not substantially change even if the apparent viscosity of the viscous fluid 3 changes. It is possible to control the magnetic field by appropriately applying a variable magnetic field suitable for the temperature, and the temperature dependence of the viscous fluid 3 can be reduced. Further, in this embodiment, since the thermocouple 15 is integrated with the peripheral wall portion 14 by molding, it is possible to obtain a strong integrated structure with mass production efficiency and reliably prevent leakage of the viscous fluid 3 to the outside. it can.

  Further, as a result of integrally molding the thermocouple 15 with the peripheral wall portion 13 as described above, in this embodiment, the peripheral wall portion 13 does not require the groove portion as in the first embodiment, and the lid 14 also has a protrusion that engages with the groove portion. The part is also unnecessary. Therefore, the peripheral wall portion 13 and the lid 14 are respectively formed with endless annular recesses 13a and annular projections 14a that are engaged with each other. 14 are fixed together.

  In the present embodiment as described above, the thermocouple 15 is integrally formed on the peripheral wall portion 13, but the thermocouple 17 may be integrally formed on the lid 16 as shown in FIGS. 7 and 8, for example. Also by this, the conductive portion 17a of the thermocouple 17 is integrated in the cover 16 in an embedded state, and one end of the two metal pieces forming the conductive portion 17a is exposed on the upper surface of the cover 16 and the “temperature” The tip portion 17b as the “sensing portion” is configured to protrude. Further, the other end of the two metal pieces is exposed on the outer peripheral surface of the lid 16, and the conductive extension portion 17 c connected to each of the two pieces extends to the outside.

  The magnetic field control viscous fluid-filled dampers 1 and 12 of each embodiment described above can be variously modified. For example, although the thermocouples 9, 15, and 17 are illustrated as “temperature sensors”, other temperature sensors such as a platinum resistance thermometer or a thermistor may be used. Further, the shape of the sealed container 2 may be a rectangular tube shape instead of a cylindrical shape, or may not include the stirring tube portion 8.

Control Method of Magnetic Field Control Viscous Fluid Enclosed Damper [FIGS. 9 to 18] : Next, a control method of magnetic field control viscous fluid encapsulated damper will be described. Here, the magnetic field control viscous fluid shown in the second embodiment of FIG. An example using the enclosed damper 12 is shown. Note that the following description is the same even when other forms and modifications are used.

  FIGS. 9 and 10 show a magnetic field control active damper 21, which includes a damper portion 22 and a drive portion 23. The damper portion 22 includes a magnetic field control viscous fluid-filled damper 12, a magnetic shield bracket 24 that supports the damper 12, and a movable bracket 27 that can be rotated by a drive portion 23 and holds magnets 25 and 26. On the other hand, the drive unit 23 includes a motor 28 and a bracket 29 that supports the motor 28.

  In the magnetic field control viscous fluid-filled damper 12, the lid 14 is fixed to the magnetic shield bracket 24 by adhesion in this embodiment. On the other hand, a support pin protruding from the support object is inserted into the stirring cylinder portion 8 to be fixed to the support object.

  The magnetic shield bracket 24 includes a fixed portion 24a and a mounting leg portion 24b of the magnetic field control viscous fluid-filled damper 12, and is attached by, for example, screwing or bonding the mounting leg portion 24b to the inner bottom surface of the housing of the disk drive device. . The fixed portion 24a is formed by forming a projecting piece portion 24d that encloses the peripheral wall portion 13 and the floating support portion 7 of the magnetic field control viscous fluid-filled damper 12 from the outside along the circumferential direction on the disc-like base portion 24c. Therefore, the overall shape is substantially U-shaped. The inner peripheral surface of the projecting piece portion 24d is substantially the same diameter as the outer diameter of the lid 14 of the magnetic field control viscous fluid-filled damper 12, so that the magnetic field control viscous fluid-filled damper 12 has the lid 14 inside the projecting piece portion 24d. It is attached to the fixing portion 24a so as to be fitted while being fitted. In addition, the attachment leg part 24b is connected with the fixed part 24a in the position which does not interfere with the movable range of the movable bracket 27 mentioned later.

  The magnetic shield bracket 24 having such a structure is formed of a material that easily absorbs magnetic flux, that is, has a high magnetic permeability, and constitutes a “magnetic shield member” in the present invention. The specific material is formed of a ferromagnetic material having a high magnetic permeability such as silicon steel, ferrite, permalloy, cobalt-based amorphous, iron, or nickel. In addition, although the fixing | fixed part 24a and the attachment leg part 24b may be comprised as a separate member, in this embodiment, it is comprised as an integral thing which cannot be separated unless it is based on the cutting | disconnection of a raw material.

  The movable bracket 27 is formed by forming, on a rectangular base portion 27a, a projecting piece portion 27b that encloses the peripheral wall portion 13 and the floating support portion 7 of the magnetic field control viscous fluid-filled damper 12 from the outside along the circumferential direction. For this reason, the overall shape is substantially U-shaped like the magnetic shield bracket 24. The inner diameter of the projecting piece 27b is slightly large enough to create a gap between the outer diameter surface of the projecting piece 24d of the magnetic shield bracket 24, and the length along the circumferential direction of the projecting piece 27b is magnetic. It is approximately the same length as that of the projecting piece 24 d of the shield bracket 24. For example, silicon steel, ferrite, permalloy, cobalt-based amorphous, iron, nickel, and the like can be used as the material of the movable bracket 27 itself, so that a magnetic field is almost taken into the magnetic shield bracket 24 to thereby move the movable bracket 27. 27 can be prevented from going outside.

  Magnets 25 and 26 are attached to the projecting piece 27b, respectively. The magnets 25 and 26 are not only magnetic materials such as paramagnetic materials and diamagnetic materials that are magnetized by receiving an external magnetic field to generate a different polarity, but are also magnetized in advance when an external magnetic field acts on them. Also included are magnetic materials such as ferromagnets with high magnetic susceptibility that increase the degree of. Specifically, a magnetic material made of carbon steel, silicon steel, alnico, Ferrox Dewar, ferrite, cobalt, nickel, iron, permalloy, neodymium, or the like can be used. The magnets 25 and 26 are attached so that the opposite poles face each other with the magnetic field control viscous fluid-filled damper 12 sandwiched, such that one of them is an N pole and the other is an S pole.

  Further, as shown in FIG. 10, a rotating shaft 28 a protruding from the motor 28 of the drive unit 23 is fixed to the rectangular base portion 27 a of the movable bracket 27. Therefore, the movable bracket 27 is rotated by a predetermined amount by the motor 28 around the rotation shaft 28a. The rotation control of the motor 28 is performed by a control controller (not shown).

  Next, the operation of the magnetic field control active damper 21 will be described. In the state of FIG. 9 and FIG. 10, as shown in FIG. 11, the magnetic particles mixed in the viscous fluid 3 of the magnetic field control viscous fluid-filled damper 12 are parallel and high by the magnets 25 and 26 facing opposite poles. A transverse magnetic field MR represented by dense magnetic lines of force acts directly and uniformly. Therefore, in this magnetic field state, the magnetic particles are oriented in the viscous fluid 3 along the lines of magnetic force thereof, so that the viscosity of the viscous fluid 3 changes and the vibration damping characteristics of the magnetic field control viscous fluid sealing damper 12 change. .

  Then, from this magnetic field state, the movable bracket 27 is rotated 90 degrees clockwise by the motor 28 as shown in FIG. Then, the magnets 25 and 26 attached to the protruding piece portion 27b are in a state of overlapping each other with the protruding piece portion 24d of the magnetic shield bracket 24. Therefore, the transverse magnetic field MR formed between the magnets 25 and 26 is deflected so that the magnetic field lines pass through the inside of the magnetic shield bracket 24 made of a high permeability material, as shown in FIG. Accordingly, the transverse magnetic field MR hardly acts on the viscous fluid 3, the orientation of the magnetic particles as described above is hardly formed, and the viscosity of the viscous fluid 3 becomes a magnetic field state in which the viscosity hardly changes.

  As described above, by switching between the magnetic field state and the non-magnetic field state, the vibration damping characteristics of the magnetic field control viscous fluid-filled damper 12 can be variably changed. Since the transverse magnetic field MR by the magnets 25 and 26 can be applied directly and uniformly to the magnetic particles sufficiently, for example, the rotation angle is adjusted stepwise and the magnets 25 and 26 and If the length overlapping with the projecting piece 24d of the magnetic shield bracket 24 is changed stepwise or linearly, further analog variable control of vibration damping characteristics becomes possible.

  Next, a vibration control method using a specific magnetic field control active damper 21 will be described.

  The magnetic field control active damper 21 is used as shown in FIG. 14, for example. In FIG. 14, a mechanical chassis 31 of a disk drive device including a recording data reading device 30 that moves in the radial direction of a disk medium M such as a CD or a DVD is illustrated as an object to be supported. This is an example applied to the vibration isolation structure of the mechanical chassis 31 mounted on the in-vehicle CD changer. Of course, the number of magnetic field control active dampers 21 may be increased or decreased depending on the mounting form. .

  The magnetic field control active damper 21 is attached by inserting support pins 32 protruding from the four corners of the mechanical chassis 31 into the stirring cylinder portion 8 of the magnetic field control viscous fluid-filled damper 12. 28 is connected to the controller 34 provided in the mechanical chassis 31 via the wiring 33, and is driven under the control of the controller 34. The controller 34 may be dedicated to vibration control of the mechanical chassis 31, or may be used for controlling the drive system of the reading device 30.

  Further, the controller 34 is connected to the conductive extension 15 c of the thermocouple 15 of the magnetic field control viscous fluid-filled damper 12, and receives temperature data (current in this embodiment) obtained by directly measuring the viscous fluid 3. Further, the controller 34 stores a vibration control program in a memory (not shown), which is read out by an arithmetic processing unit in the controller 34 and subjected to arithmetic processing with the direct temperature of the viscous fluid 3 measured by the thermocouple 15 as an input. Is executed, the rotation angle of the movable bracket 27 by the motor 28, that is, the overlapping length of the magnets 25 and 26 with respect to the projecting portion 24d of the magnetic shield bracket 24, that is, the shielding length is controlled.

  Various control methods are possible to perform such a control operation. The simplest method is, for example, whether the temperature of the viscous fluid 3 detected by the thermocouple 15 causes the transverse magnetic field MR to act. When the predetermined threshold value is exceeded, the controller 34 outputs a drive signal for rotating the movable bracket 27 to the motor 28 so that the magnetic field state shown in FIG. On the other hand, when the temperature of the viscous fluid 3 falls below a predetermined threshold value, a drive signal for rotating the movable bracket 27 is output to the motor 28 so as to be in the no magnetic field state of FIG. Active vibration isolation of the mechanical chassis 31 can be performed by simple ON-OFF control in a magnetic field state or no magnetic field state, which is performed by the controller 34 executing a vibration control program.

  In addition to this, for example, the following control method can further increase the accuracy of the measured temperature of the viscous fluid 3. That is, in this method, the controller 34 controls the strength of the transverse magnetic field MR according to the temperature of the viscous fluid 3 by executing a program for performing the control flow shown in FIG.

  The controller 34 reads the temperature data from the thermocouple 15 at regular time intervals (s10). Then, the magnetic force calculation flow of steps s12 to s32 is executed, and the magnetic force corresponding to the acquired temperature (sensor temperature) TZb of the viscous fluid 3, that is, the strength of the magnetic force applied to the viscous fluid 3 as the transverse magnetic field MR is obtained. Next, data relating to the rotation angle of the movable bracket 27, that is, the shielding length of the transverse magnetic field MR by the magnetic shield bracket 24 is obtained from the data table of the memory (s34). Then, a drive signal for rotating the movable bracket 27 based on the acquired data is output to the motor 28 (s36). As a result, the movable bracket 27 rotates, and the vibration control can be performed to make the damping characteristic of the magnetic field control viscous fluid-filled damper 1 variable.

  Next, a modification of the above embodiment will be described. In the above embodiment, the movable bracket 27 to which the magnets 25 and 26 are attached is rotated. However, the magnetic shield bracket 24 may be rotated without rotating the movable bracket 27.

  In the above-described embodiment, the example in which the magnetic shield bracket 24 is attached to the inner bottom surface of the housing via the attachment leg portion 24b and the motor 28 via the bracket 29 has been described. Such a mounting structure may be used. FIG. 16 shows the internal structure of an in-vehicle CD player in which a mechanical chassis 36 that drives and reproduces a disk medium M is housed in a metal box-shaped chassis 37 in an outer casing 35. This is to be assembled to the dashboard in the passenger compartment. The magnetic shield bracket 24 of the magnetic field control active damper 21 is directly fixed to the side wall 37 a of the box-type chassis 37. As shown in FIG. 17, the box-shaped chassis 37 is formed with an insertion hole 37 b formed in accordance with the rotation locus so that the protruding piece 27 b of the movable bracket 27 can rotate. The motor 28 is fixed to the side wall 37 a of the box-type chassis 37 via a bracket 38 having a hat-shaped cross section. As described above, the magnetic field control active damper 21 can be attached so as to be integrated with the box-type chassis 37 that is a supported object, when the mechanical chassis 36 that is the object of vibration isolation is a supported object. By adopting a simple mounting structure, it is possible to contribute to size reduction of the disk drive device while realizing high-level vibration isolation of the mechanical chassis 36.

  In the above embodiment, the length along the circumferential direction of the magnets 25 and 26 attached to the projecting piece portion 24d of the magnetic shield bracket 24 and the projecting piece portion 27b of the movable bracket 27 is set to be approximately the same length. In order to enhance the shielding effect, the protruding piece 24d of the magnetic shield bracket 24 may be made longer.

  According to the magnetic field control active damper 21 and the control method of the magnetic field control viscous fluid-filled damper 12 as described above, a magnetic field can be directly and uniformly applied to the magnetic particles in the viscous fluid 3. it can. Therefore, the active vibration isolation control that slightly changes the viscosity of the viscous fluid 3 is realized by slightly changing the strength of the transverse magnetic field MR according to the temperature of the viscous fluid 3, and a high vibration damping effect is obtained. For this reason, a wider range of anti-vibration design is possible than before, and a high vibration damping effect can be realized with a small and simple structure.

  Further, in the magnetic field control active damper 21, the viscosity of the viscous fluid 3 of the magnetic field control viscous fluid-filled damper 12 is controlled according to the temperature of the viscous fluid 3, and its vibration damping characteristics can be variably controlled. The effect can be demonstrated. Therefore, even if vibration having various vibration characteristics acts in an actual use environment such as an in-vehicle CD player, an excellent damping effect can be exhibited by magnetic field control suitable for input vibration.

BRIEF DESCRIPTION OF THE DRAWINGS It is an external view of the magnetic field control viscous fluid enclosure damper by 1st Embodiment, a division figure (A) is a front view, and a division figure (B) is the SA-SA sectional view taken on the line (A). The expansion disassembled perspective view of the SB part of FIG. 1 (A). The partial expansion perspective view of the SB part of FIG. 1 (A). FIG. 2 is an enlarged exploded perspective view corresponding to the SB portion of FIG. 1A, which is a modification of the magnetic field control viscous fluid-filled damper of FIG. 1. FIG. 3 is an enlarged perspective view corresponding to the SB portion of FIG. 1 (A) in a modified example of the magnetic field control viscous fluid-filled damper of FIG. 1. It is an external view of the magnetic field control viscous fluid enclosure damper by a 2nd embodiment, a division figure (A) is a front view, and a division figure (B) is an SC-SC line sectional view of a division figure (A). FIGS. 7A and 7B are external views of a modified example of the magnetic field control viscous fluid-filled damper of FIG. The expanded sectional view which follows the SE-SE line of FIG.7 (B). The front view which looked at the damper part of the magnetic field control active damper by one Embodiment from the arrow SG direction of FIG. The side view of the magnetic field control active damper seen from the arrow SH direction of FIG. FIG. 11 is a cross-sectional view taken along the line SE-SE in FIG. 9 schematically illustrating a magnetic field state of the magnetic field control active damper illustrated in FIGS. 9 and 10. The front view equivalent to FIG. 9 explaining operation | movement of the magnetic field control active damper of FIG. FIG. 13 is a cross-sectional view taken along the line SF-SF of FIG. 12, schematically illustrating a magnetic fieldless state of the magnetic field control active damper illustrated in FIG. 12. The top view of the internal structure of the disk drive apparatus which shows typically the use condition of the magnetic field control active damper by one Embodiment. The flowchart which shows the control method of the magnetic field control viscous fluid enclosure damper by one Embodiment. The internal structure explanatory drawing of the disc drive apparatus which shows the other attachment structure of a magnetic field control active damper. The front view of the attachment structure of the magnetic field control active damper seen from the arrow SI-SI direction of FIG. FIG. 17 is a cross-sectional view taken along line SJ-SJ in FIG. 16.

Explanation of symbols

1 Magnetic field control viscous fluid-filled damper (first embodiment)
2 Sealed container 3 Viscous fluid 4 Container body 5 Lid 5a Annular protrusion (annular convex part)
5b Protruding part 5c Mounting groove (introducing part, hole-like part)
6 peripheral wall portion 6a outward flange 6b inner peripheral surface 6c annular recess 6d groove portion 6e elastic seal piece (sealing member)
6f Curved contact surface 6g Groove (introduction part, hole-like part)
7 Floating support portion 8 Stirring tube portion 9 Thermocouple 9a Conductive portion 9b Tip portion 9c Resin layer 10 Resin sealing portion (sealing member, cured resin body)
11 Ultrasonic Fusion Part 12 Magnetic Field Controlled Viscous Fluid Enclosed Damper (Second Embodiment)
13 peripheral wall portion 13a annular recess 14 lid 14a annular projection 15 thermocouple (temperature sensor)
15a Conductive part 15b Tip part (temperature sensing part)
15c Conductive extension 16 Lid 17 Thermocouple (temperature sensor)
17a Conductive part 17b Tip part (temperature sensing part)
17c Conductive extension 21 Magnetic field control active damper 24 Magnetic shield bracket (magnetic shield member)
24d Projection pieces 25, 26 Magnet (magnetic field forming member)
27 Movable bracket (magnetic field forming member)
27b Projection piece 28 Motor (drive device)
34 Controller

Claims (13)

Viscous fluid containing magnetic particles is liquid-tightly sealed in a sealed container including a container main body having an annular open end and a lid for closing the open end, and an external magnetic field is applied to the magnetic particles. In the magnetic field control viscous fluid-filled damper in which the viscosity of the viscous fluid changes by
A magnetic field control viscous fluid-filled damper, characterized in that a temperature sensor having a temperature sensing part that comes into contact with the viscous fluid is provided inside the sealed container.   The temperature sensor has a conductive part extending from the temperature sensing part to the outside of the sealed container, and the sealed container has a gap between the introduction part of the conductive part and the conductive part contained in the introduction part. The magnetically controlled viscous fluid-filled damper according to claim 1, further comprising a sealing member that closes tightly.   The introduction portion of the sealed container is a hole-shaped portion, and the sealing member is an elastic seal piece made of a rubber-like elastic body that liquid-tightly closes the gap between the conductive portion of the temperature sensor and the hole-shaped portion. 2. Magnetic field control viscous fluid-filled damper according to 2.   The hole-shaped part of the sealed container is an attachment groove directed to at least one of the boundary between the opening end of the container main body and the lid, and the elastic seal piece is provided facing the longitudinal direction of the attachment groove. The magnetically controlled viscous fluid-filled damper according to claim 3.   3. The magnetic field control viscous fluid according to claim 2, wherein the introduction portion of the sealed container is a hole-shaped portion, and the sealing member is a resin cured body that is liquid-tightly fixed to the conductive portion of the temperature sensor and the hole-shaped portion. Enclosed damper.   The magnetically controlled viscous fluid-filled damper according to claim 5, wherein the cured resin body is a liquid resin filled and cured in a gap between the conductive portion of the temperature sensor and the hole-shaped portion.   The magnetically controlled viscous fluid-filled damper according to claim 5, wherein the cured resin body is a resin molded body integrally molded by molding so as to cover the conductive portion of the temperature sensor.   6. The magnetically controlled viscous fluid-filled damper according to claim 5, further comprising an ultrasonic fusion bonding portion for fixing the cured resin body as a sealing member and the hole-shaped portion of the sealed container.   The temperature sensor has a conductive portion extending from the temperature sensing portion to the outside of the sealed container, and the conductive portion of the temperature sensor is integrally embedded in either the container body or the lid of the sealed container by molding. 2. Magnetic field control viscous fluid-filled damper according to 2.   Either one of the annular convex part or the annular concave part which mutually engages is formed along the circumferential direction of the opening end of a container main body, The said other is provided in the cover body. Magnetic field control viscous fluid enclosure damper given in any 1 paragraph. In the control method of the magnetic field control viscous fluid sealing damper that controls the viscosity of the viscous fluid by applying an external magnetic field to the viscous fluid containing the magnetic particles sealed in the sealed container,
A temperature sensor in which the temperature sensing unit is in direct contact with the viscous fluid is installed in a sealed container of the magnetic fluid control viscous fluid-filled damper, and an external magnetic field is applied to the viscous fluid according to the direct temperature of the viscous fluid detected by the temperature sensor. A method for controlling a magnetically controlled viscous fluid-filled damper, wherein the viscosity of a viscous fluid is controlled by varying the strength of the fluid.   The method for controlling a magnetic field control viscous fluid-filled damper according to claim 11, wherein the magnetic field control viscous fluid-filled damper is any one of claims 1 to 10.   The magnetic field control member includes a magnetic field forming member that forms a transverse magnetic field in a sealed container of the viscous fluid-sealed damper, and a magnetic shield member. The magnetic fluid is applied to the viscous fluid according to the direct temperature of the viscous fluid detected by the temperature sensor. Obtain the strength of the transverse magnetic field, drive at least one of the magnetic field forming member or the magnetic shield member according to the strength, and make the external magnetic field variable by the magnetic shield member blocking the transverse magnetic field. 13. A method for controlling a magnetically controlled viscous fluid-filled damper according to claim 11 or 12, wherein the damper is applied to a fluid.

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