JP3660277B2 - Mounting device for power unit in automobile - Google Patents

Description

[0001]
BACKGROUND OF THE INVENTION
The present invention relates to a front-wheel drive vehicle in which a power unit in which an engine and a manual transmission are integrated is supported horizontally on a front portion of a vehicle body via a plurality of mounts, and more particularly to a mounting device for the power unit.
[0002]
[Prior art]
In a liquid-sealed engine mount that supports the vibration of an automobile engine, two liquid chambers that increase or decrease in volume due to vibration in the vertical direction are connected by an orifice to cause vertical damping, and the volume is reduced by vibration in the horizontal direction. Japanese Patent Publication No. 63-61533 discloses a technique in which two liquid chambers that increase and decrease are connected by an orifice so as to generate horizontal attenuation.
[0003]
[Problems to be solved by the invention]
By the way, when a power unit that integrates the engine and manual transmission is supported horizontally on the vehicle body, when the accelerator pedal is turned on and off, the power unit is centered on the differential center line of the manual transmission due to the reaction caused by the increase or decrease of the engine speed. Thus, it is known that the vibration is generated by swinging back and forth. The frequency of this vibration varies depending on the gear position at that time, but is generally in the range of 1.5 Hz to 7 Hz.
[0004]
Conventionally, the mount that supports the power unit on the vehicle body that generates damping in the front-rear direction is intended to reduce the vibration in the riding comfort area (engine feeling) with a frequency of about 10 Hz.・ Vibration when turned off could not be reduced sufficiently.
[0005]
The present invention has been made in view of the above-described circumstances, and in a vehicle in which a power unit in which an engine and a manual transmission are integrated is supported horizontally on a vehicle body, vibrations when an accelerator pedal is turned on / off by setting the mount thereof. The purpose is to reduce effectively.
[0006]
[Means for Solving the Problems]
In order to achieve the above object, according to the first aspect of the present invention, in a front-wheel drive vehicle in which a power unit in which an engine and a manual transmission are integrated is supported horizontally on a front portion of a vehicle body via a plurality of mounts. A side engine in which at least one of the plurality of mounts has both a function of attenuating vibrations in the vertical direction and a function of attenuating vibrations in the longitudinal direction of the vehicle body by an orifice. The side engine mount is an orifice against vibrations around the left and right axes of the power unit caused by turning on / off the accelerator pedal , in order to achieve both the vibration reduction performance and ride comfort performance associated with turning on / off the accelerator pedal. the attenuation is set the frequency at which maximum 1.5Hz~7Hz by Together are, for vibrations of small amplitude in the ride area, power unit mounting device in a motor vehicle, characterized in that the attenuation by the orifice has set the frequency at which a maximum 10Hz vicinity is proposed.
[0007]
According to the above configuration, at least one of the plurality of mounts supporting the power unit with integrated engine and manual transmission, constituted by vertical vibration and side engine mount together damping vibrations of the vehicle body longitudinal direction, the side since attenuation for the longitudinal direction of the vehicle body vibrations due to the orifice of the engine mount has set the frequency at which a maximum 1.5Hz～7Hz, possible to effectively reduce the vibration around lateral axis of the power unit by turning on and off of the accelerator pedal Can do . In addition, the side engine mount is set to a frequency at which the attenuation to the vehicle longitudinal vibration by the orifice is maximized when a small amplitude vibration is input, so that the vibration in the riding comfort region having a frequency near 10 Hz is set. It is possible to effectively reduce both vibration reduction performance and ride comfort performance associated with accelerator pedal on / off.
[0008]
According to the invention described in claim 2 , in addition to the configuration of claim 1 , the side engine mount is a mount having the longest distance from the differential center line among the plurality of mounts. A device for mounting a power unit in an automobile is proposed.
[0009]
According to the above configuration, of the plurality of mounts that support the power unit in which the engine and the manual transmission are integrated, the mount having the largest distance from the differential center line is the side engine mount mount that attenuates vibration in the longitudinal direction of the vehicle body. there so, it is possible to effectively reduce the vibration around lateral axis of the power unit by turning on and off the accelerator pedal.
[0010]
According to the invention described in claim 3 , in addition to the configuration of claim 1 or 2 , the side engine mount for attenuating vibration in the longitudinal direction of the vehicle body is located in the casing, the casing, An elastic body that can be elastically deformed so as to alternately increase or decrease the volume of the pair of liquid chambers in the casing according to vibrations in the front-rear direction of the power unit, and the cross-sectional area between the pair of liquid chambers is 15 mm ² or longer. is 300mm or more, and to be communicated with each other by the orifice set in the volume 4500 mm ³ or more, the power unit of the mounting device is proposed in an automobile.
[0011]
According to the above configuration, it is possible to effectively reduce vibration around the left and right axes of the power unit due to turning on / off of the accelerator pedal, and it is possible to effectively reduce vibration in a riding comfort region having a frequency near 10 Hz. Thus, it is possible to achieve both vibration reduction performance and ride comfort performance associated with the on / off of the accelerator pedal.
[0012]
The side engine mount M1, the transmission mount M2, the front engine mount M3, and the rear engine mount M4 correspond to the mount of the present invention. In particular, the side engine mount M1 has a distance from at least one mount or differential center line of the present invention. Corresponds to the largest mount.
[0013]
DETAILED DESCRIPTION OF THE INVENTION
Hereinafter, embodiments of the present invention will be described based on examples of the present invention shown in the accompanying drawings. 1 to 4 show an embodiment of the present invention. FIG. 1 is a perspective view of a power unit mounted horizontally on the front of a vehicle body, and FIG. 2 is an enlarged sectional view taken along line 2-2 of FIG. 3 is a cross-sectional view taken along line 3-3 of FIG. 2, and FIG. 4 is a graph showing characteristics of the attenuation coefficient of the mount with respect to the input frequency.
[0014]
As shown in FIG. 1, the power unit P mounted on the front of the vehicle body of an automobile is formed by integrating an engine E located on the left side and a manual transmission T located on the right side. The engine E is disposed with the cylinder block 11 and the cylinder head 12 on the lower side and the upper side, respectively, and is disposed horizontally with the crankshaft directed in the lateral direction of the vehicle body.
[0015]
The power unit P is supported on the vehicle body via four mounts. The first mount is a side engine mount M1, and the left side surface of the engine E is supported on the left front side frame 13. The second mount is a transmission mount M2, and supports the right side surface of the manual transmission T to the right front side frame 14. The third mount is a front engine mount M3, and the front surface of the engine E is supported by a cross member 15 that connects the left and right front side frames 13,14. The fourth mount is a rear engine mount M4, and the rear surface of the engine E is supported by a cross member (not shown) connecting the left and right front side frames 13,14. In FIG. 1, the rear engine mount M4 is hidden behind the engine E and cannot be seen.
[0016]
The side engine mount M1, the transmission mount M2, the front engine mount M3, and the rear engine mount M4 viewed from the side are arranged above the differential center line L extending in the left-right direction below the power unit P. The front engine mount M3 and the rear engine mount M4 are arranged on the front upper side and the rear upper side. The side engine mount M1 is located higher than the transmission mount M2, and the distance A from the differential center line L of the side engine mount M1 is the maximum of the four mounts M1 to M4. That is, the side engine mount M1 is disposed at a position farthest from the differential center line L among the four mounts M1 to M4.
[0017]
Next, the structure of the side engine mount M1 will be described based on FIG. 2 and FIG. The side engine mount M1 includes a liquid seal mount, and has a function of attenuating not only vertical vibrations but also longitudinal vibrations.
[0018]
The side engine mount M1 includes a casing 21 having a cylindrical main body portion 21a and a plate-like attachment portion 21b extending radially outward from a lower end thereof, and a substantially cylindrical outer portion inside the main body portion 21a. The tube 22 is fitted and fixed by the crimping portion 21c. The first elastic body 23 is fixed to the inner periphery of the outer cylinder 22 by baking, and the cup-shaped inner cylinder 24 is fixed to the inner periphery of the first elastic body 23 by baking. A cup-shaped second elastic body 25 is fixed to the lower end of the main body 21 a of the casing 21 by baking, and the partition wall 26 is fixed by baking along the upper edge of the second elastic body 25. The first liquid chamber 27 defined between the first elastic body 23 and the partition wall 26 and the second liquid chamber 28 defined between the second elastic body 25 and the partition wall 26 are connected via an orifice 26 a penetrating the partition wall 26. Communicate with each other.
[0019]
In the middle portion of the outer cylinder 22 in the vertical direction, two notches 22a and 22a positioned in the longitudinal direction of the vehicle body and two orifices positioned in the lateral direction of the vehicle body and communicating with the two notches 22a and 22a. 22b and 22b are formed. The orifices 22b and 22b are partitioned between the inner peripheral surface of the main body portion 21a of the casing 21 by processing the outer peripheral surface of the outer cylinder 22 into a thin wall. By forming the two notches 23a and 23a on the front and rear surfaces of the first elastic body 23 so as to face the inner circumference of the two notches 22a and 22a of the outer cylinder 22, the notches 22a and 22a of the outer cylinder 22 are formed. The notches 23a and 23a of the first elastic body 23 cooperate to partition the front third liquid chamber 29 and the rear fourth liquid chamber 30, and the third liquid chamber 29 and the fourth liquid chamber 30 are divided into two. The individual orifices 22b and 22b communicate with each other.
[0020]
Thus, in the side engine mount M1, the mounting portion 21b of the casing 21 is fixed to the left front side frame 13 by a plurality of bolts 31 and nuts 32, and the support plate 33 fixed to the inner cylinder 24 is a bolt 34 and nuts. It is fixed to the mounting bracket 36 of the engine E through 35.
[0021]
Next, the operation of the embodiment of the present invention having the above configuration will be described.
[0022]
Of the four mounts M1 to M4 that support the power unit P, when vertical vibration is input from the power unit P to the side engine mount M1, the inner cylinder 24 connected to the engine E is connected to the front side frame 13 The volume of the first liquid chamber 27 increases or decreases as the first elastic body 23 is elastically deformed by being displaced relative to the cylinder 22 in the vertical direction. When the engine E relatively moves downward and the volume of the first liquid chamber 27 decreases, the liquid in the first liquid chamber 27 passes through the orifice 26a of the partition wall 26 and flows into the second liquid chamber 28, and the second elastic body. 25 is inflated. On the contrary, when the engine E relatively moves upward and the volume of the first liquid chamber 27 increases, the liquid in the second liquid chamber 28 passes through the orifice 26a of the partition wall 26 while the second elastic body 25 is contracted. It flows into the liquid chamber 27. In this manner, the volume of the first liquid chamber 27 and the second liquid chamber 28 is alternately increased and decreased, and the liquid passes through the orifice 26a, thereby generating a damping force that suppresses the vertical vibration of the power unit P.
[0023]
By the way, when the driver depresses the accelerator pedal and the engine speed increases rapidly, or when the driver releases the accelerator pedal and the engine speed decreases rapidly, the differential center line that becomes the swing center by the reaction The power unit P vibrates back and forth around L, and the frequency of the back-and-forth vibration is approximately 1.5 Hz to 7 Hz although it varies depending on the gear position. This vibration has a relatively large amplitude and is about ± 5 mm in the front-rear direction at the position of the side engine mount M1 farthest from the differential center line L.
[0024]
When the power unit P vibrates in the front-rear direction at the position of the side engine mount M1 in this way, the inner cylinder 24 connected to the engine E of the side engine mount M1 moves in the front-rear direction with respect to the outer cylinder 22 connected to the front side frame 13. Since the first elastic body 23 is elastically deformed and the volumes of the third liquid chamber 29 and the fourth liquid chamber 30 are alternately increased and decreased, the third liquid chamber 29 and the fourth liquid chamber 30 are When the liquid passes through the orifices 22b and 22b to be connected, attenuation that suppresses the longitudinal vibration of the power unit P is generated.
[0025]
By setting the characteristics of the orifices 22b and 22b to, for example, a cross-sectional area of 15 mm ² or more, a length of 300 mm or more, and a volume of 4500 mm ³ or more, the attenuation coefficient for longitudinal vibration with an amplitude of ± 5 mm is 1.2 Ns / frequency at a frequency of 5 Hz. The vibration in the front-rear direction that occurs when the accelerator pedal is turned on / off can be effectively reduced. In the same setting of the orifices 22b and 22b, when a vibration with a minute amplitude of about ± 1 mm is input in the front-rear direction, a damping coefficient of 0.8 Ns / mm or more is secured in the riding comfort region with a frequency of 8 Hz. It is possible to achieve both vibration reduction performance and ride comfort performance associated with pedal on / off.
[0026]
In the example shown in FIG. 4, by setting the characteristics of the orifices 22b and 22b separately from the above, the peak of the attenuation coefficient that reduces the vibration in the front-rear direction generated when the accelerator pedal is turned on and off is adjusted to 7 Hz. And the peak of the attenuation coefficient for improving riding comfort performance is adjusted to 9 Hz. In addition, the conventional example shown with a chain line has shown the characteristic of the side engine mount M1 which does not have the vibration damping function of the front-back direction.
[0027]
As described above, the frequency at which the maximum attenuation coefficient is obtained when a relatively large longitudinal vibration having an amplitude of about ± 5 mm is input to the side engine mount M1 is set to 1.5 Hz to 7 Hz, and the amplitude is ± By setting the frequency at which the maximum attenuation coefficient can be obtained when relatively small longitudinal vibrations of about 1 mm are input, in the vicinity of 10 Hz, vibration reduction performance and ride comfort performance associated with turning on / off the accelerator pedal Can be made compatible. In particular, since the side engine mount M1 farthest from the differential center line L, which is the center of oscillation of the power unit P, is selected as a mount that generates damping that reduces vibration in the front-rear direction, the vibration in the front-rear direction of the power unit P is more effective. Can be suppressed.
[0028]
As mentioned above, although the Example of this invention was explained in full detail, this invention can perform a various design change in the range which does not deviate from the summary.
[0029]
For example, in the embodiment, among the side engine mount M1, the transmission mount M2, the front engine mount M3, and the rear engine mount M4, only the side engine mount M1 attenuates vibration in the longitudinal direction of the vehicle body. Similarly, the vibration in the longitudinal direction of the vehicle body may be attenuated.
[0030]
【The invention's effect】
As described above, according to the first to third aspects of the present invention, in the front-wheel drive vehicle, at least one of the plurality of mounts that horizontally support the power unit at the front of the vehicle body attenuates the vibration in the vertical direction. And a side engine mount located on the side of the engine that has both the function of damping the vibration in the longitudinal direction of the vehicle body by the orifice, and the frequency at which the attenuation to the longitudinal vibration of the vehicle body by the orifice of the side engine mount is maximized Is set to 1.5 Hz to 7 Hz, it is possible to effectively reduce vibration around the left and right axes of the power unit due to the accelerator pedal being turned on and off . Moreover the side engine mount, since attenuation for orifices longitudinal direction of the vehicle body vibration when the vibration of small amplitude is input is set to the frequency that maximizes the 10Hz vicinity, frequency effect vibrations in comfort region of 10Hz vicinity Therefore, it is possible to achieve both the vibration reduction performance and ride comfort performance associated with turning on / off the accelerator pedal.
[0031]
Further, according to the invention of claim 2 , among the plurality of mounts that support the power unit in which the engine and the manual transmission are integrated, the mount having the longest distance from the differential center line is the side that attenuates vibration in the longitudinal direction of the vehicle body. Since it is an engine mount, it is possible to effectively reduce vibration around the left and right axes of the power unit caused by turning on / off the accelerator pedal.
[0032]
In particular, according to the invention of claim 3, the one mount of the side engine that attenuates the vibration in the longitudinal direction of the vehicle body is in the casing and the casing, and the volume of the pair of liquid chambers in the casing is set to the power unit. And an elastic body that can be elastically deformed so as to alternately increase or decrease in accordance with vibrations in the front-rear direction, and the space between the pair of liquid chambers is set to a cross-sectional area of 15 mm ² or more, a length of 300 mm or more, and a volume of 4500 mm ³ or more Since the orifices communicate with each other, vibrations around the left and right axes of the power unit due to the accelerator pedal being turned on and off can be effectively reduced, and vibrations in the riding comfort region with a frequency in the vicinity of 10 Hz can be effectively reduced. This makes it possible to achieve both vibration reduction performance and ride comfort performance associated with turning the accelerator pedal on and off. The
[Brief description of the drawings]
1 is a perspective view of a power unit mounted horizontally on the front of a vehicle body. FIG. 2 is an enlarged sectional view taken along line 2-2 in FIG. 1. FIG. 3 is a sectional view taken along line 3-3 in FIG. ] Graph showing characteristics of mount attenuation coefficient with respect to input frequency [Explanation of symbols]
21 ... Casing 22b .. Orifice 23 ... First elastic body (elastic body)
29 ... Third liquid chamber (liquid chamber)
30 ... Fourth liquid chamber (liquid chamber)
L ... Differential center line M1 ... Side engine mount (mount, at least one mount, mount with the greatest distance from the diff center line)
M2 ... Transmission mount (mount)
M3 ... Front engine mount (mount)
M4 ... Rear engine mount (mount)
P ... Power unit T ... Manual transmission

Claims (3)

In a front-wheel drive vehicle in which a power unit (P) in which an engine (E) and a manual transmission (T) are integrated is supported horizontally on the front of a vehicle body via a plurality of mounts (M1 to M4),
At least one of the plurality of mounts (M1 to M4) has both a function of damping the vibration in the vertical direction and a function of damping the vibration in the longitudinal direction of the vehicle body by the orifice (22b, 22b). Side engine mount (M1) located on the side of the engine (E),
The side engine mount (M1) is designed to reduce the vibration around the left and right axes of the power unit (P) when the accelerator pedal is turned on and off in order to achieve both the vibration reduction performance and ride comfort performance associated with turning the accelerator pedal on and off. The frequency at which the attenuation by the orifices (22b, 22b) is maximized is set to 1.5 Hz to 7 Hz, and the vibration by the orifices (22b, 22b) is applied to vibration with a minute amplitude in the riding comfort region. attenuation, characterized in that to set the frequency at which a maximum 10Hz vicinity, the power unit mounting device in automobiles. The vehicle according to claim 1 , wherein the side engine mount (M1) is a mount having the longest distance from the differential center line (L) among the plurality of mounts (M1 to M4). Power unit mounting device. The side engine mount (M1) that attenuates vibrations in the longitudinal direction of the vehicle body is in the casing (21) and the casing (21), and a pair of liquid chambers (29, 30) in the casing (21). An elastic body (23) that can be elastically deformed so as to alternately increase or decrease the volume of the power unit (P) in accordance with vibrations in the front-rear direction, and the cross-sectional area between the pair of liquid chambers (29, 30) is 15 mm. ² or more, a length of 300mm or more, characterized in that it is communicated with each other by the orifice set in the volume 4500 mm ³ or more (22b, 22b), a power unit mounting device in a motor vehicle according to claim 1 or 2.

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