KR20040026827A - Variable damping apparatus of door opening and shutting sound for vehicle - Google Patents

Abstract

PURPOSE: A variable damping apparatus of opening/shutting sound for a vehicle is provided to detect vibration of a door by using an LVDT(Linear Variable Differential Transformer) and to improve opening/shutting sound as to frequency band. CONSTITUTION: A door glass(24) is installed between a door outer panel(34) and a door inner panel(36) including a weather strip(38). A door belt rail(26) is installed inside the door inner panel. A dynamic stabilizer(28) is fixed to a dynamic stabilizer plate(40) installed to a side of the belt rail. The dynamic stabilizer comprises a damper(44) filled with magnetor-rheological fluid and an LVDT(Linear Variable Differential Transformer,46). A rubber pad is hinged to the other surface of the dynamic stabilizer, contacting a surface of the door glass regularly. An electronic control unit(32) detects control of a damper of the dynamic stabilizer and a signal of the LVDT and controls with set information. Thereby, opening/shutting sound is improved by controlling spring coefficient according to frequency as to shutting noise of the door.

Description

VARIABLE DAMPING APPARATUS OF DOOR OPENING AND SHUTTING SOUND FOR VEHICLE}

The present invention relates to a variable opening and closing attenuation device for a vehicle door, and more particularly, to improve the door opening and closing sound by using a door glass as a dynamic damper for preventing the vibration of the door (LVDT: Linear Variable Differential) Detect door vibration by changing the opening / closing speed of the door using a transformer, and suppress the door vibration by the magnetorheological fluid-filled damper by dynamic stabilizer to improve the door opening and closing sound by frequency band It relates to a variable opening and closing sound attenuation device of a vehicle door.

In general, the opening and closing sound of the door is the most important first impression for general buyers to contact and evaluate the car, and plays an important role in determining the consumer's desire to purchase and the quality of the vehicle.

Objective evaluation factors of the door opening and closing sound can be largely divided into sound pressure, loudness, decay time, sharpness, roughness, and the like. There are Semantic Differential Method (PCM) and Paired Comparison Method (PCM).

SDM is mainly used to evaluate the characteristics of the sound by selecting the vocabulary representing the characteristics of the sound to be evaluated, and comparing the characteristics of the sound by analyzing the evaluation values for each vocabulary. It is often used to determine which sound is best.

That is, in order to improve the door opening and closing sound, the door structure should rapidly attenuate high frequency vibration noise of 2.5kHz or more due to resonance, and in particular, the vibration noise in the 1 ~ 2kHz region sensitive to the human ear should be reduced.

In addition, in order to identify the problem area of the door opening and closing sound, it is necessary to measure the vibration of each part of the door and to measure the frequency response function of the parts exhibiting the vibration corresponding to the problem noise frequency to determine whether the door structure is resonated by each part.

The conventional door structure according to this is shown in FIG. 1, and a diagram showing the improvement in the case of evaluating the door opening and closing sound and the specific high frequency noise using the conventional door structure is shown in FIG.

The door 2 attaches and forms a window glass rail 8 with a predetermined gap between the door inner panel 4 and the door outer panel 6, and on the inner side facing the stabilizer rubber pad 10 The door glass 14 is interposed between the door inner panel 4 and the upper edge of the door outer panel 6, and the door glass 14 is inserted and installed to be supported therebetween.

Evaluating the door opening and closing sound by the above-described method of the door (2) it can be seen that the noise (V) is greatly generated at a specific high frequency (L), in order to improve the specific door opening and closing speed High noise (V) generated at a specific high frequency (L) is reduced to low noise (V1).

As described above, when evaluating the door opening and closing sound, only a specific door opening and closing speed is evaluated, thereby improving the frequency-specific improvement of the door opening and closing sound due to resonance caused by various door opening and closing speed changes.

As the door glass of the door does not play more than the mass when viewed from the vibration side, the stabilizer rubber pad is a fixed type and cannot absorb the impact of the door glass during the flow of the door glass, and the stabilizer rubber pad has a characteristic value There is a limit to reducing only certain vibration frequencies.

In order to solve the problems of the prior art made as described above, an object of the present invention is to improve the door opening and closing sound (LVDT :) by using the door glass as a dynamic damper for preventing the vibration of the door. By detecting the vibration of door by changing the opening and closing speed of the door by using Linear Variable Differential Transformer) and suppressing the vibration of the door by various door opening and closing speed by dynamic stabilizer, The present invention provides a variable sound damping device.

The present invention for realizing this

A door glass inserted and installed between the door outer panel and the door inner panel of the vehicle door via a weather strip;

A door belt rail installed at a predetermined interval inside the door inner panel;

A dynamic stabilizer comprising a damper and an elevity in which a magnetorheological fluid is enclosed in a dynamic stabilizer plate attached to a predetermined area on one side of the door belt rail;

A rubber pad installed to be in contact with one surface of the door glass while being hinged to the other side of the dynamic stabilizer;

To provide a vehicle door vibration preventing device comprising a damper control of the dynamic stabilizer and an electronic control device that is electrically connected to sense the signal of the elevity and control by a predetermined information.

The dynamic stabilizer is operated by a fixed plate fixed to a dynamic stabilizer plate, a support plate hinged with rubber pads facing each other at a predetermined distance from the fixed plate, and an electric signal of an electronic controller between the fixed plate and the support plate. And a damper having a magnetic rheological fluid sealed therein, and an elevity which is installed to connect an electric signal to an electronic control device for measuring vibration at the lower side of the damper. To provide.

The damper includes a hollow spring having an attachment plate formed on both sides thereof, a magnetorheological fluid filled and enclosed in the spring, and an electromagnet arranged to be magnetized by an electrical signal of an electronic controller at a predetermined distance from the spring to the outside. The present invention provides a variable opening and closing attenuation device for a vehicle door.

1 is a view showing a door structure according to the prior art.

Figure 2 shows a graph of the evaluation of the door structure according to the prior art and the case of a particular high frequency noise reduction.

Figure 3 is a view showing the configuration of the door vibration preventing device according to the present invention.

4 shows a damper applied to FIG. 3;

5 is a graph showing the effect of the door vibration preventing device according to the present invention in a graph comparison.

Figure 6 is a view for explaining the principle (a), structure (b), output characteristics (c) of the LV applied to the present invention with reference.

7 is a view for explaining the magnetic variable fluid applied to the present invention for reference.

* Description of the symbols for the main parts of the drawings *

22: door open and close variable attenuation device 23: door

24: door glass 26: door bell trail

28: dynamic stabilizer 30: rubber pad

32: Electronic control device 34: Door outer panel

36: door inner panel 38: weather strip

40: dynamic stabilizer plate 42: magnetic rheology fluid

44: damper 46: elvity

50: fixed plate 52: support plate

54: mounting plate 56: hollow spring

58: electromagnet

Hereinafter, with reference to the accompanying drawings a preferred embodiment of the present invention will be described in more detail.

Figure 3 is a view showing the configuration of the variable opening and closing sound attenuation device of the door according to the invention, Figure 4 is an enlarged view showing a damper applied to Figure 3, Figure 5 is a variable opening and closing sound of the door according to the present invention It is a figure which showed the effect of the attenuation apparatus compared with graph.

The opening / closing sound variable attenuator 22 of the vehicle door includes a door glass 24, a door bell trail 26, a dynamic stabilizer 28, a rubber pad 30, and an electronic controller 32 of the vehicle door 23. It consists of.

The door glass 24 is inserted and installed between the door outer panel 34 and the door inner panel 36 of the vehicle door 23 with the weather strip 38 interposed therebetween.

The door bell trail 26 is provided in parallel with the door glass 24 at regular intervals from the inside of the door inner panel 36.

The dynamic stabilizer 28 includes a damper 44 and an elevity 46 encapsulating the magnetorheological fluid 42 in a dynamic stabilizer plate 40 attached to a predetermined area on one side of the door belt rail 26. ), And one side is fixedly mounted.

The dynamic stabilizer 28 fixes the fixed plate 50 to the dynamic stabilizer plate 40, and hinges the rubber pad 30 facing the fixed plate 50 at a predetermined interval to the support plate 52. (48) a damper (44) provided with a magnetorheological fluid (42) provided between the fixed plate (50) and the support plate (52) so as to operate by an electrical signal of the electronic control device (32); The damper 44 is configured to include an elevity 46 which is installed to connect an electric signal to the electronic control device 32 measuring vibrations.

The damper 44 has a hollow spring 56 having an attachment plate 54 formed on both sides thereof, a magnetorheological fluid 42 filled and sealed in the spring 56, and a predetermined distance from the spring 56. And an electromagnet 58 arranged to be magnetized by an electrical signal of the electronic control device 32 around the outside.

The rubber pad 30 is installed to be in constant contact with one surface of the door glass 24 while being connected to the other side of the dynamic stabilizer 28 by a hinge 48.

The electronic controller 32 is electrically connected to the damper 44 of the dynamic stabilizer 28 and the signal of the LV 46 to sense the signal and to control the preset information.

6 is a view for explaining the principle (a), structure (b), the output characteristic (c) of the elevity applied to the present invention, the principle (a) of the elevity 46 is The coil 60 wound around the wire becomes a magnet by flowing an electric current. On the contrary, when the magnet is inserted into or removed from the coil 60, the current flows through the coil 60. This is called electromagnetic induction. It is a phenomenon found.

The two properties of the electromagnetic induction are applied to a transformer 62 which is used as a power source for home power supply. The transformer 62 winds coils of four angles in opposite positions to the primary coil 64. When the AC voltage V1 flows, the iron core alternately changes the direction of the magnetic poles, so that the secondary coil 66 flows the AC voltage V2 proportional to the winding at the same frequency.

The LV 46 is a transformer having a variable iron core for reading the change in length by applying the principle of electromagnetic induction.

Referring to the structure (b) of the elevity 46, the primary coil 68, the secondary coil 70, and the variable iron core 72 are described.

This is a type in which the primary coil 68 is sandwiched between two secondary coils 70. The winding ends of the secondary coils 70 are connected to each other so that the two terminals of the winding start are used as output terminals.

In this state, when an alternating voltage is applied to the primary coil 68, when the iron core 72 is located at the center of the two secondary coils 70, the voltages of the mutual secondary coils are the same, and the output voltage does not occur. The position of the core is called the equilibrium point.

On the other hand, when the iron core is shifted from the equilibrium point, mutual inductance changes between the primary coil and the two secondary coils, and the voltage closer to the iron core is higher than that of the secondary coil. Output the difference as an alternating voltage.

LVDT's shape is thinner and longer than thicker and shorter, so it has better linearity and output safety.

Referring to the output characteristic c of the LV 46, the relationship between the iron core position x and the output voltage E 0 of the LV varies linearly over a wide range.

The dotted line 74 indicates voltages E1 and E2 occurring in the two secondary coils, and a relationship of E0 = (E1-E2) is established between them.

The reason why the voltage E0 is V-shaped at the equilibrium point is that the output voltage phase angle of AC is inverted by 180 degrees.

The reason why the voltage near the equilibrium point is not zero is that the output voltage does not become zero due to magnetic or electrical imbalance even if the iron core is in the center position due to the residual voltage. It happens

In addition, the magnetorheological fluid 42 applied to the present invention will be described with reference to FIG. 7. The magnetorheological fluid (hereinafter referred to as MR fluid) is a micron-sized magnet in a nonconductive solvent such as silicone oil or mineral oil. It is a non-colloidal solution in which dispersible particles are dispersed.If the magnetic field is not loaded, the dispersed particles have Newtonian fluid properties.However, when the magnetic field is loaded, the dispersed particles are polarized, forming fibers in a direction parallel to the loaded magnetic field. It is a fluid that is resistant to flow (solidification).

Until now, research on electric rheological fluid (ER fluid), which is a kind of controllable fluid like MR fluid, has been mainly limited to semi-active devices such as linear dampers and mounts, but recently, the advantages of the fast response speed of ER fluid are There is an active research on MR fluids which have the same disadvantages as low yield stress, narrow operating temperature range, and especially the susceptibility to impurities.

Referring to the operation of the present invention made as described above, the electronic control device 32 when opening and closing the door of the vehicle by the set information to the opening and closing sound vibration generated during the opening and closing of the door 23 to the elevity 46 Will be measured.

Accordingly, the LCD 46 receives the measured voltage, and the electronic control device 32 converts the voltage into displacement and converts the voltage into a displacement, and the door through the FFT (Fast Fourier Transform) of the acceleration component obtained through the second derivative over time. The frequency having the maximum vibration component of (23) is determined.

Therefore, the electronic controller 32 is a dynamic stabilizer that avoids the natural frequency of the door 23 in which an anxious closing sound occurs due to the excitation of the door 23 by the current opening / closing speed of the door 23 based on the determined frequency. The voltage is applied to the damper 44 side electromagnet 58 by the preset data.

As the voltage is applied to the electromagnet 58, the magnetorheological fluid (MR) 42 in the spring 56 can reduce the door closing noise of high frequency caused by vibration and resonance of the door 23 as much as possible. You have a spring factor.

In addition, the dynamic stabilizer 28 dynamically controls the door closing sound of the high frequency caused by door resonance during the opening and closing of the door 23 for each frequency.

In other words, in Fig. 5, the initial vibration opening and closing speed of the conventional door (V1) is reflected in the design is lowered to the vibration (V2), but afterwards it was not reflected in the design had to listen to the opening and closing sound (V3) to worry about the door opening and closing speed, but the present invention By applying the variable opening and closing sound attenuation device 22 of the door, the spring coefficient of the door vibration according to the opening and closing speed of the door 23 is added to or subtracted from the magnetism degree by the electromagnet 58 to the spring 56 in which the magnetorheological fluid 42 is enclosed. Corresponding control for each door closing sound frequency can be controlled to attenuate such that the reduction of vibrations V2 of the opening and closing sound of the door is improved.

The present invention has the effect of improving the opening and closing sound by controlling the spring coefficient for each frequency according to the door closing sound to improve the productability of the product.

In addition, there is an effect of improving the opening and closing sound of the door by reflecting all the vibrations according to the opening and closing speed of the door to reflect the door opening and closing sound of the prior art.

In addition, the rubber pad hinged to the dynamic stabilizer at the time of vertical flow of the door glass is in constant contact with the door glass, thereby absorbing the impact of the door glass when the door glass flows.

On the other hand, the spring in which the magnetorheological fluid is sealed in the damper has a spring coefficient for attenuation of the door closing noise of the high frequency caused by vibration and resonance of the door, thereby reducing the maximum.

In addition, the connection position of the rubber pad is variable in contact with the damper for each case, so that the characteristic value of the damping is varied, thereby reducing the various vibration frequencies.

Claims (3)

A door glass 24 inserted and installed between the door outer panel 34 of the vehicle door 23 and the door inner panel 36 via a weather strip 38; A door belt rail 26 installed at a predetermined interval inside the door inner panel 36; One side of the door belt rail 26 is composed of a damper 44 and an elevating member 46 having a magnetorheological fluid 42 encapsulated in a dynamic stabilizer plate 40 attached to a predetermined area. A fixed-mounted dynamic stabilizer 28, The rubber pad 30 is installed to be in constant contact with one surface of the door glass 24 while being connected to the hinge 48 on the other side of the dynamic stabilizer 28, And an electronic control device 32 which is electrically connected to control the damper 44 of the dynamic stabilizer 28 and the signal of the LV 46 to be controlled by preset information. Variable opening and closing sound attenuation device of the vehicle door. The dynamic stabilizer 28 includes a fixed plate 50 fixed to the dynamic stabilizer plate 40 and a rubber pad 30 facing the fixed plate 500 at regular intervals. 48. A damper 44 having a support plate 52 provided therein and a magnetorheological fluid 42 installed between the fixed plate 50 and the support plate 52 to operate by an electrical signal of the electronic control device 32. And an elevity 46 which is installed under the damper 44 so as to apply an electrical signal to the electronic control device 32 measuring vibrations. Variable damping device. 3. The damper 44 according to claim 2, wherein the damper 44 comprises a hollow spring 56 having an attachment plate 54 formed on both sides thereof, a magnetorheological fluid 42 filled and sealed in the spring 56, and the spring ( 56) opening and closing variable attenuation device for a vehicle door, characterized in that the configuration comprises an electromagnet (58) arranged to be magnetized by an electrical signal of the electronic control device (32) at an outer periphery.