JP2019083269A - Damper damping force variable device, damper system comprising the device, and vehicle mounted with the damper system - Google Patents

Abstract

To provide a damper damping force variable device including a mechanism for efficiently exhausting heat generated from a step-up transformer even when the step-up transformer is covered with an electromagnetic shield, and to provide a damper system comprising the device, and a vehicle mounted with the damper system.SOLUTION: A damper damping force variable device 400 is a device controlling damping force of a damper using an electric viscous fluid, and comprises: a boosting control circuit board on which a boosting transformer 436 and a microprocessor for controlling the boosting transformer are mounted; and airtight cases 410, 420 that accommodate the boosting control circuit board. The boosting transformer is covered with a box-shaped electromagnetic shield 440 via a filling material. The electromagnetic shield has a box shape having one face facing an airtightness case, the one face abutting on the inner face of the airtight case, the one face facing the airtight case having projected and recessed structure.SELECTED DRAWING: Figure 3

Description

  The present invention relates to a technology for actively changing damper damping force, and more particularly to a damper damping force variable device that varies damping force by an electrical signal, a damper system including the device, and a vehicle equipped with the damper system. It is.

  Various damping force variable dampers have been researched and developed in recent years in order to achieve both improvement in riding comfort and improvement in traveling operability in a vehicle (for example, an automobile). There are several types of damping force control methods, but methods using electro-rheological fluid (ERF) have attracted attention.

  ERF is a fluid whose viscosity coefficient changes even under the same temperature and pressure when placed in an electric field, and has the feature that the viscosity can be reversibly controlled over a wide range of orders of magnitude by an external electric field. The ERF-based damping force variable damper is highly responsive because it can directly control the viscosity of the fluid with an electrical signal, and it is highly reliable because it does not require a movable part to adjust fluid resistance (failure risk) There is an advantage of

  For example, in Patent Document 1 (Japanese Patent Application Laid-Open No. 11-287283), an outer cylinder containing an electro-rheological fluid inside and provided with vanes extending radially inward on the inner peripheral side, and relative rotation inside the outer cylinder Between the respective vanes so as to be provided and located between the outer cylinder and the inner cylinder and the inner cylinder provided with other vanes extending radially outward on the outer peripheral side and adjacent to each other in the circumferential direction An electro-rheological fluid is provided between the first and second liquid chambers provided at least in the inner cylinder and the outer cylinder and the inner cylinder being relatively rotated. A flow path means for circulating the electric field, an electric field applying portion provided in the inner cylinder and located in the middle of the flow path means, for applying an electric field to the electro-rheological fluid flowing through the flow path means; A wiring portion which is inserted and which feeds power to the electric field applying portion from the outside, and is provided in the inner cylinder so as to be located around the wiring portion. , Damper Using electrorheological fluid comprising constituting a sealing means for blocking the wiring portion from the electrorheological fluid flowing through the flow path means, is disclosed.

  According to Patent Document 1, the wiring portion can be disposed in a non-contact state with the electro-rheological fluid, and it is not necessary to provide a complicated mechanism such as a seal member around the wiring portion, and the wiring portion can It is said that the connection operation at the time of connection to the connector can be facilitated, and the workability at the time of assembly can be improved.

  Further, in Patent Document 2 (Japanese Patent Application Laid-Open No. 2007-064331), an electro-rheological fluid is sealed in a case, and a rotating body is incorporated in the case, one electrode is provided on the rotating body, and the other electrode is one electrode The electrorheological fluid damper is provided in the case in such a manner that the gap between the two electrodes is filled with the electrorheological fluid, and the electric field is applied between the electrodes to control the torque of the rotating body. An electrorheological fluid damper is disclosed, which is characterized in that an enclosed region of an electrorheological fluid and a gas chamber are partitioned by a plate-like elastic partition member.

  According to Patent Document 2, in the electro-rheological fluid damper, it is supposed that the volume change due to the temperature of the electro-rheological fluid can be reliably compensated and a stable damping characteristic can be secured.

JP 11-287283 A Japanese Patent Application Publication No. 2007-064331

  Control of a damping force variable damper using an ERF is usually performed by an on-board electronic control unit (ECU). The use environment of a vehicle (for example, an automobile) is a very severe environment for electronic devices, and on-board ECUs are required to have high heat resistance, high weather resistance, and high vibration resistance. Then, from the viewpoint of weather resistance, the on-vehicle ECU is usually housed in an airtight case. Further, with the development of car electronics, in recent years, countermeasures against electromagnetic interference (EMI) have also become an important issue.

  Viscosity control of ERF requires application of high voltage (e.g., 1-5 kV). Therefore, a vehicle-mounted ECU that controls the damping force variable damper needs a boost control circuit (for example, a circuit including a microprocessor, a switching element, a capacitor, a regulator, a boost transformer, and the like) for generating a high voltage.

  Here, the step-up transformer is a component having the largest power consumption (about 10 W) of the power consumption of the step-up control circuit (for example, about 50 W per system). Furthermore, the step-up transformer is a representative electromagnetic noise source in a step-up control circuit, and it is desirable that an electromagnetic shield be provided as a countermeasure against EMI.

  In other words, the step-up transformer, which is most likely to generate heat in the step-up control circuit, is covered with the electromagnetic shield and mounted inside the airtight case for the on-vehicle ECU. As a result, depending on the use environment of the vehicle, it becomes difficult to sufficiently cool the heat generation of the step-up transformer, and the temperature in the on-vehicle ECU exceeds the heatproof temperature of the electronic components that constitute the step-up control circuit. It is feared that it will cause dysfunction.

  Patent Documents 1 and 2 unfortunately do not have any description or suggestion regarding the technology for solving the overheat problem in the on-vehicle ECU having such a boost control circuit. Therefore, it is an object of the present invention to solve the problem of overheating in a vehicle-mounted ECU having a step-up control circuit, a mechanism for efficiently removing heat generated by the step-up transformer even when the step-up transformer is covered by an electromagnetic shield. An object of the present invention is to provide a damper damping force variable device having the same and a damper system provided with the device. Another object of the present invention is to provide a vehicle equipped with the damper system.

  (I) One embodiment of the present invention is a device for controlling the damping force of a damper using an electro-rheological fluid, wherein a step-up transformer and a microprocessor for controlling the step-up transformer are mounted; An airtight case for accommodating the step-up control circuit board, the step-up transformer being covered with a box-shaped electromagnetic shield via a filler, and the electromagnetic shield facing the airtight case; It is an object of the present invention to provide a damper damping force variable device characterized in that one surface of a box shape is in contact with the inner surface of the airtight case, and the one surface facing the airtight case has a concavo-convex structure.

The present invention can add the following improvements and changes to the above-described damper damping force variable device (I).
(I) In the electromagnetic shield, the surface area of the one surface facing the airtight case is larger than the surface area of the one surface facing the step-up control circuit board.
(Ii) The box shape of the electromagnetic shield is a square frustum shape, and the one surface opposite to the airtight case is a bottom surface of the square frustum shape.
(Iii) The airtight case has a concavo-convex structure in a region in contact with the electromagnetic shield.
(Iv) The electromagnetic shield has an average shape in which the one surface facing the airtight case is convex outward.

  (II) Another aspect of the present invention is a damping force variable damper system having a damper using an electro-rheological fluid and a damper damping force variable device, wherein the damper damping force variable device is the damper damping force described above. It is a variable device, and the damper damping force variable device and the damper are connected by a wire harness. The damping force variable damper system is provided.

  (III) Yet another aspect of the present invention is a damping force variable damper system having a damper using an electro-rheological fluid and a damper damping force variable device, wherein the damper damping force variable device is the above-described damper damping It is a force variable device, and the damper damping force variable device is disposed directly on the damper, to provide a damping force variable damper system.

  (IV) Yet another aspect of the present invention is a vehicle equipped with a variable damping force damper system, wherein the variable damping force damper system is the variable damping force damper system described above, To provide

  According to the present invention, the damper damping force variable device has a mechanism for efficiently removing heat generated by the step-up transformer even when the step-up transformer in the step-up control circuit is covered with an electromagnetic shield. A damper system can be provided, and the overheat problem in a vehicle-mounted ECU having a boost control circuit can be solved. In addition, a vehicle equipped with the damper system can be provided.

BRIEF DESCRIPTION OF THE DRAWINGS It is a partial see-through perspective schematic diagram which shows an example of the damping force variable damper system which concerns on 1st embodiment of this invention, and a motor vehicle carrying this damper system. It is a disassembled perspective schematic diagram which shows an example of the damper damping force variable apparatus which concerns on 1st embodiment. It is an enlarged section mimetic diagram showing an example of a damper damping force variable device concerning a first embodiment. FIG. 7 is an enlarged cross-sectional schematic view showing an example of a damper damping force variable device according to a second embodiment. It is an enlarged section mimetic diagram showing an example of a damper damping force variable device concerning a third embodiment. It is an enlarged section mimetic diagram showing an example of a damper damping force variable device concerning a 4th embodiment. It is a partial see-through perspective view showing an example of a damping force variable damper system concerning a 5th embodiment, and an automobile carrying the damper system.

  Hereinafter, embodiments according to the present invention will be more specifically described with reference to the drawings. However, the present invention is not limited to the embodiments described herein, and can be appropriately combined with the known technology or improved based on the known technology without departing from the technical concept of the invention. .

  For example, although an automobile equipped with a damping force variable damper system is described as an example in the present specification, the vehicle of the present invention is not limited to an automobile, and may be a motorcycle or a railway. It is also good. Moreover, the technical idea of the damping force variable damper system of the present invention is not limited to the damper system for a suspension, and other vibration suppression (for example, engine mount), shock absorption (for example, bumper), torque control It is also possible to apply to (for example, a clutch, a torque converter).

First Embodiment
(Damping force variable damper system and automobile equipped with the damper system)
FIG. 1 is a partially transparent perspective schematic view showing an example of a damping force variable damper system according to a first embodiment of the present invention and an automobile equipped with the damper system. An automobile 100 shown in FIG. 1 is provided with a suspension 200 for each of the four wheels, and the suspension 200 has a spring 210 and a damper 220. The damper 220 is a damper using ERF as a working fluid.

  Each damper 220 is connected to a damper damping force variable device 400 which is a type of on-vehicle ECU via a wire harness 300. The damper damping force variable device 400 has a boost control circuit board, which will be described later, inside thereof. A combination of the damper 220, the wire harness 300 and the damper damping force variable device 400 is a damping force variable damper system according to the first embodiment.

  The wheels of the automobile 100 vibrate by receiving forces of various frequencies, amplitudes, and directions depending on road surface conditions during traveling, speed, acceleration / deceleration, cornering, and the like. The variable damping force damper system according to the present invention can quickly adjust the damping force of each damper 220 individually to such various road surface inputs, thereby achieving high tire contactability (running operability) and high vehicle attitude stability. It is compatible with the nature (ride comfort). In addition, as described above, the damping force variable damper system of the present invention using the damper 220 using ERF has high responsiveness because the viscosity of the ERF can be directly controlled by an electric signal, and the movable property for adjusting fluid resistance It has the advantage of high reliability (small risk of failure) because it does not require a part.

  The damping force variable damper system in the present invention does not deny that it includes components other than the damper 220 of the suspension 200 (for example, the spring 210, a bush and an arm not shown). Moreover, in FIG. 1, although the damper damping force variable apparatus 400 is drawn as a central ECU system which controls four dampers 220 collectively (the four wire harnesses 300 are concentrated), the present invention is limited thereto It is not something to be done. For example, it may be divided into a damper damping force variable device in which two front wheels are combined and a damper damping force variable device in which two rear wheels are combined, or four each are connected to separate damper damping force variable devices May be

(Damper damping force variable device)
FIG. 2 is an exploded perspective schematic view showing an example of the damper damping force variable device according to the first embodiment. As described above, the damper damping force variable device 400 is illustrated as a central ECU method (including four boosting control circuits) that collectively controls the four dampers 220.

  As shown in FIG. 2, the damper damping force variable device 400 is a substrate (boost control circuit board 430) in which a boost control circuit is formed in an airtight case (airtight case upper lid 410 + airtight case lower lid 420). ) Is accommodated. The boost control circuit board 430 is configured, for example, by mounting the microprocessor 432, the switching element 433, the capacitor 434, the regulator 435, the boost transformer 436, etc. on the printed circuit board 431. The step-up transformer 436 is covered with a box-shaped electromagnetic shield 440 as a measure against EMI. In addition, the boost control circuit board 430 is provided with a connector 450 for connecting to the wire harness 300.

  The dimensions of the airtight case (airtight case upper lid 410 + airtight case lower lid 420) are, for example, 200 mm × 150 mm × 50 mm, and the dimensions of the step-up transformer 436 are, for example, 40 mm × 40 mm × 40 mm It is.

  FIG. 3 is an enlarged schematic cross-sectional view showing an example of the damper damping force variable device according to the first embodiment. As shown in FIG. 3, the step-up transformer 436 is mounted on the printed circuit board 431 via the input / output pin 437 and is covered by the electromagnetic shield 440. By covering with the electromagnetic shield 440, electromagnetic noise generated in the step-up transformer 436 can be shielded, and EMI to other elements of the step-up control circuit can be suppressed.

  The frequency of the electromagnetic noise generated by the step-up transformer 436 is about 0.06 to 2 MHz. Therefore, from the viewpoint of the shielding effect, the electromagnetic shield 440 is preferably made of a metal material having high conductivity (for example, copper, aluminum).

  The box-shaped electromagnetic shield 440 may have a configuration in which one surface facing the printed circuit board 431 is an opening surface, and the one surface is also covered with a metal material having high conductivity (that is, six surfaces). It may be a configuration in which all is covered with a highly conductive metal material). When one surface opposite to the printed circuit board 431 is an opening surface, it is more preferable to form a dummy circuit 438 on the printed circuit board 431 to provide an electromagnetic shielding effect.

  Between the step-up transformer 436 and the electromagnetic shield 440, a high thermal conductivity filler 460 (for example, a high thermal conductivity potting material) is filled. In the electromagnetic shield 440, one surface (upper surface in the figure) of the box shape facing the airtight case (the airtight case upper cover 410 in FIG. 3) is in contact with the inner surface of the airtight case (airtight case upper cover 410). ing. Thus, the heat generation of the step-up transformer 436 can be efficiently transferred and dissipated to the airtight case upper lid 410 via the filler 460 and the electromagnetic shield 440.

  From the viewpoint of heat dissipation, it is preferable that the airtight case (here, at least the airtight case upper cover 410) in contact with the electromagnetic shield 440 be made of a corrosion-resistant metal material (eg, aluminum alloy, stainless steel). By forming the airtight case from a corrosion-resistant metal material, there are also secondary effects that can ensure the heat resistance, weather resistance, and durability required of the on-vehicle ECU.

  Furthermore, it is preferable to interpose a heat conductive material 470 (for example, heat dissipation grease) between the airtight case top cover 410 and the top surface of the electromagnetic shield 440. Thereby, the air gap which may be generated between the airtight case top cover 410 and the upper surface of the electromagnetic shield 440 can be filled, and a good heat transfer path (effective heat transfer area) can be secured.

  On the other hand, as a result of many trial manufactures by the present inventors, detailed experiments and investigations, the airtight case top cover 410 in the outer peripheral area (area of about 15 to 25 area%) of the upper surface (that is, the contact surface) of the electromagnetic shield 440. It was found that the heat transfer contact with this tends to decrease with time. In order to suppress this adverse effect, the surface area of the upper surface of the electromagnetic shield 440 in contact with the airtight case upper lid 410 should be larger than the area (projected area) of the upper surface (one surface facing the printed circuit board 431). It is preferable to comprise.

  Specifically, the surface area of the upper surface of the electromagnetic shield 440 is preferably 1.2 times or more, more preferably 1.3 times or more, and still more preferably 1.35 times or more of the facing projected area of the upper surface. As a result, a sufficient effective heat transfer area can be ensured over time.

  As a measure for enlarging the surface area of the contact surface of the electromagnetic shield 440, in the first embodiment, as shown in FIG. 3, the uneven surface is formed on the contact surface of the electromagnetic shield 440. For example, when a concavo-convex structure is formed by press drawing on a copper plate having a thickness of 0.5 mm, the surface area can be expanded by about 1.4 times compared to that before the processing.

  In addition, the concavo-convex structure also has the effect of enhancing the retention of the heat conducting material 470 between the airtight case top cover 410 and the top surface of the electromagnetic shield 440. In addition, the uneven structure enables the upper surface of the electromagnetic shield 440 to exhibit a certain degree of springability, and the tolerance of the processing dimensional accuracy of the airtight case top cover 410 and the electromagnetic shield 440 is expanded, and the vibration resistance in heat transfer contact There are also secondary effects such as the improvement of sex.

Second Embodiment
The second embodiment is different from the first embodiment in the configuration of the electromagnetic shield, and the others are the same. Therefore, only parts different from the first embodiment will be described.

(Damper damping force variable device)
FIG. 4 is an enlarged cross-sectional schematic view showing an example of the damper damping force variable device according to the second embodiment. In FIG. 4, the airtight case upper lid is drawn in a floating state (the airtight case upper lid and the airtight case lower lid are not fitted) so that the configuration of the electromagnetic shield can be easily understood.

  As shown in FIG. 4, the electromagnetic shield 441 of the damper damping force variable device 401 has an average shape in which the contact surface with the airtight case upper lid 410 is convex outward (convex upward in the drawing). The contact surface can exhibit elasticity like a thin plate spring. Thereby, the effect of the improvement of the tolerance of the processing dimension accuracy of the airtight case top cover 410 or the electromagnetic shield 441 and the improvement of the vibration resistance in the heat transfer contact can be enhanced compared to the first embodiment.

  In addition, "average shape" said here shall mean the shape at the time of averaging concavo-convex structure (in other words, the shape before forming concavo-convex structure).

Third Embodiment
The third embodiment is different from the first embodiment in the configuration of the airtight case top lid, and the others are the same. Therefore, only parts different from the first embodiment will be described.

(Damper damping force variable device)
FIG. 5 is an enlarged schematic sectional view showing an example of the damper damping force variable device according to the third embodiment. As shown in FIG. 5, the airtight case (here, the airtight case upper lid 411) of the damper damping force variable device 402 has a concavo-convex structure in a region in contact with the electromagnetic shield 440. Thereby, the retention of the heat conduction material 470 between the airtight case top lid 411 and the upper surface of the electromagnetic shield 440 can be enhanced compared to the first embodiment.

  In addition, in the third embodiment, the concavo-convex structure of the airtight case top lid 411 and the concavo-convex structure of the upper surface of the electromagnetic shield 440 are engaged, so that the vibration resistance in heat transfer contact is greatly improved.

  As a matter of course, the third embodiment may further incorporate the configuration of the second embodiment.

Fourth Embodiment
The fourth embodiment is different from the first embodiment in the configuration of the electromagnetic shield, and the others are the same. Therefore, only parts different from the first embodiment will be described.

(Damper damping force variable device)
FIG. 6 is an enlarged cross-sectional schematic view showing an example of the damper damping force variable device according to the fourth embodiment. As shown in FIG. 6, in the electromagnetic shield 443 of the damper damping force variable device 403, the area (projected area) of the contact surface with the airtight case upper lid 410 faces the contact surface (the printed circuit board 431 faces). It is configured to be larger than the area (projected area) of one side). In other words, the electromagnetic shield 443 has a shape in which the square frustum is turned upside down, and the bottom surface of the square frustum is a contact surface with the airtight case top cover 410. The fourth embodiment is advantageous in that the effective heat transfer area of the contact surface (upper surface in the drawing) of the electromagnetic shield 443 and the airtight case upper lid 410 can be easily expanded.

  As a matter of course, the fourth embodiment may further incorporate the configurations of the first to third embodiments.

Fifth Embodiment
The fifth embodiment is different from the first embodiment in the arrangement of the damper damping force variable device, and the other is the same. Therefore, only parts different from the first embodiment will be described.

(Damping force variable damper system and automobile equipped with the damper system)
FIG. 7 is a partially transparent perspective schematic view showing an example of a damping force variable damper system according to a fifth embodiment and an automobile equipped with the damper system. The automobile 101 shown in FIG. 7 is provided with a suspension 201 for each of the four wheels, and the suspension 201 has a spring 210 and a damper 221. The damper 221 is a damper using ERF as a working fluid.

  In the first embodiment, the damper 220 is connected to the damper damping force variable device 400 via the wire harness 300, but in the fifth embodiment, the damper damping force variable device 404 is directly connected to the individual dampers 221. It is arranged. Each damper damping force variable device 404 is connected to the central ECU 405 via the wire harness 301.

  The central ECU 405 is an ECU for controlling the four damper damping force variable devices 404 in an integrated manner. The central ECU 405 is not an essential component in the present invention, but preferably disposed. As the configuration of the damper damping force variable device 404, any configuration of the first to fourth embodiments can be used except that one system of boost control circuit is included.

  In the fifth embodiment, since the damper damping force variable device 404 is directly disposed on the damper 221, a cable with a high voltage specification (usually a thick insulating sheath is covered as the wire harness 301 to ensure insulation withstand voltage). Communication cables (generally, thin and light cables) can be used. This greatly contributes to the ease of wiring and weight reduction of the wire harness.

  The damper damping force variable device 404 is preferably fixed to the damper 221 via a fixing rib (for example, screwed and fixed to the outer cylinder of the damper 221). In other words, between the damper damping force variable device 404 and the damper 221, a gap (air gap) through which air can flow is formed in a region other than the fixed rib and the high voltage connector for viscosity control of the ERF. Is preferred.

  By providing the air gap, it is possible to suppress unwanted heat flow between the damper damping force variable device 404 and the damper 221. As a result, it is possible to prevent the viscosity fluctuation of the ERF in the damper 221 due to an unexpected temperature change and the overheating of the damper damping force variable device 404.

  The embodiments described above have been described in order to help the understanding of the present invention, and the present invention is not limited to only the specific configurations described. For example, it is possible to replace part of the configuration of the embodiment with the configuration of the common sense of the person skilled in the art, and to add the configuration of the common sense of the person skilled in the art to the configuration of the embodiment. That is, the present invention can delete, add to other configurations, and add other configurations without departing from the technical concept of the invention with respect to some of the configurations of the embodiments of the present specification. .

100, 101 ... car,
200, 201 ... suspension, 210 ... spring, 220, 221 ... damper,
300, 301 ... wire harness,
400, 401, 402, 403, 404 ... damper damping force variable device, 405 ... central ECU,
410, 411 ... airtight case upper lid, 420 ... airtight case lower lid,
430 ... boost control circuit board, 431 ... printed circuit board, 432 ... microprocessor,
433 ... switching element, 434 ... capacitor, 435 ... regulator,
436 ... step-up transformer, 437 ... input / output pin, 438 ... dummy circuit,
440, 441, 442, 443 ... electromagnetic shield, 450 ... connector,
460 ... filler, 470 ... heat conductive material.

Claims (8)

A device for controlling the damping force of a damper using an electrorheological fluid, comprising:
A step-up control circuit board on which a step-up transformer and a microprocessor for controlling the step-up transformer are mounted;
An airtight case for housing the boost control circuit board,
The step-up transformer is covered with a box-shaped electromagnetic shield via a filler,
The damper is characterized in that one surface of the box shape facing the airtight case is in contact with the inner surface of the airtight case, and the one surface facing the airtight case has a concavo-convex structure. Damping force variable device. In the damper damping force variable device according to claim 1,
The damper damping force variable device according to claim 1, wherein the electromagnetic shield has a surface area of the one surface facing the airtight case larger than an area of the one surface facing the step-up control circuit board. In the damper damping force variable device according to claim 2,
The box shape of the electromagnetic shield is a square frustum shape,
The damper damping force variable device according to claim 1, wherein the one surface facing the airtight case is a bottom surface of the quadrangular frustum shape. In the damper damping force variable device according to claim 2 or 3,
The damper damping force variable device according to claim 1, wherein the airtight case has a concavo-convex structure in a region in contact with the electromagnetic shield. The damper damping force variable device according to any one of claims 2 to 4.
The damper damping force variable device according to claim 1, wherein the electromagnetic shield has an average shape in which the one surface facing the airtight case is convex outward. A damping force variable damper system comprising a damper using an electro-rheological fluid and a damper damping force variable device, comprising:
The damper damping force variable device is the damper damping force variable device according to any one of claims 1 to 5,
A damper force variable damper system characterized in that the damper damping force variable device and the damper are connected by a wire harness. A damping force variable damper system comprising a damper using an electro-rheological fluid and a damper damping force variable device, comprising:
The damper damping force variable device is the damper damping force variable device according to any one of claims 1 to 5,
A damper force variable damper system characterized in that the damper damping force variable device is disposed directly on the damper.   A vehicle equipped with the variable damping damper system according to any one of claims 6 or 7 mounted on the variable damping damper system.

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