JP2005059806A - Engine mounting system - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To reduce assembly cost by reducing the number of vehicle body tightening points on a power plant P while satisfying such contradicting requests as a reduction in idle vibration and the displacement of the power plant by driving reaction in a well-balanced state when the power plant P is laterally loaded on an FF vehicle. <P>SOLUTION: Torque rods 40 and 56 are integrally mounted on mount members 3 and 5 disposed on both right and left sides of the power plant P, and the load support points f1 and f2 of the power plant P by these both mount members 3 and 5 are made higher than a conventional three-point pendulum mount to set vertical distances D1 and D2 between the load support points f1 and f2 and a roll shaft R. A separate torque rod connecting the power plant P to a vehicle body is abolished. <P>COPYRIGHT: (C)2005,JPO&NCIPI

Description

  The present invention relates to an engine mount system for mounting a power plant in an engine room of an automobile, and particularly to the technical field of a layout configuration of mount members in the case of horizontal mounting with a crankshaft directed in the vehicle width direction.

  Conventionally, as this type of engine mounting system, for example, as disclosed in Patent Literature 1, both ends of the longitudinal direction (direction in which the crankshaft extends) of the power plant in which the engine and the transmission are arranged in series are respectively provided. Some vehicle body side frames located on the left and right ends of the engine room are elastically supported by two main mount members. Since such a mounting member is responsible for most of the weight of the power plant, a certain level of dynamic spring is required at least in the vertical direction, which tends to be disadvantageous in terms of absorbing and blocking engine vibration.

  In other words, vibration generated mainly around the roll axis due to torque fluctuations during engine idle operation, etc., is not so large in amplitude, but is in a low frequency range that makes humans feel uncomfortable. It is desirable to prevent transmission to Therefore, in general, an inertia main shaft mount is employed in which the mount members at the left and right ends are arranged as close as possible to the roll inertia main shaft (hereinafter simply referred to as the roll shaft) of the power plant. In this way, even if the mount member is somewhat hard in the vertical direction (having a high dynamic spring), the dynamic spring around the roll axis becomes soft, thereby suppressing transmission of idle vibration to the vehicle body. Can do.

  However, if the dynamic spring around the roll axis is softened in this way, for example, when the engine drive output (torque) fluctuates greatly, such as during sudden acceleration, the entire power plant rolls greatly due to the reaction force (torque). There is a risk that the shaft rotates (rolls) around the shaft, thereby causing a problem of interference with surrounding components, or excessive deformation of the rubber portion of the mount member, resulting in a loss of durability.

  In this regard, in the case of a general inertia spindle mount, in addition to the main mount members arranged on the left and right sides of the power plant, for example, as disclosed in Patent Document 2, a stopper member for regulating the rolling of the power plant (Roll stoppers) are usually provided before and after the power plant.

  For example, as disclosed in Patent Document 3, the support point of the power plant by the left and right mounting members is set to be slightly higher, and the entire power plant is swingably supported like a pendulum. There is also known a structure in which a torque rod for restricting the swinging is provided independently so as to connect the lower end portion of the power plant and the vehicle body side (hereinafter referred to as a three-point pendulum mount).

In the three-point pendulum mount, since the support point of the power plant load is farther from the roll inertia spindle than the general inertia spindle mount, there is a possibility that the reduction of idle vibration is somewhat disadvantageous. When force (torque) is applied, the rotation of the power plant around the roll axis is restricted by the left and right mounting members themselves, and the mass of the power plant functions as an inertial body that suppresses the swinging of the power plant. It is considered that even if only one torque rod is used, the vibration can be effectively suppressed.
French Patent Application Publication No. 2737008 Japanese Utility Model Publication No. 63-122264 German Patent Application No. 4209613

  By the way, in each of the conventional engine mount systems, in addition to the main mount members on the left and right sides receiving the weight of the power plant, the roll displacement is independently regulated before and after the power plant, or at the lower end, etc. A mounting member is provided. For this reason, when assembling a power plant to the vehicle body in an automobile assembly line, in addition to the mounting fastening work at the minimum two places necessary to support the power plant, it can be mounted at another place apart from that. Fastening work is required, which is a major obstacle to reducing assembly costs.

  In recent years, fuel efficiency regulations and exhaust gas regulations for automobiles have become stricter, and along with this, the number of auxiliary equipment for the engine itself and equipment installed in the engine room is also increasing. From the viewpoint of securing space, it is desirable that the number of vehicle body fastening points of the power plant is as small as possible.

  The present invention has been made in view of the above points, and an object of the present invention is to provide a mounting system for an engine (power plant) that is horizontally mounted on a so-called FF vehicle or the like, and includes two mounting members and a torque rod. We devised the arrangement configuration to regulate the displacement of the power plant due to the driving reaction force and to ensure sufficient durability of the mount member, while reducing the number of fastening points with the power plant body and reducing assembly costs Is to plan.

  In order to achieve the above-mentioned object, the inventors of the present application have conducted intensive experiments and research. As a result, the left and right mounting members are integrally formed based on the above-described configuration of the three-point pendulum mount (Patent Document 3). By providing a torque rod and setting the power plant load support point by both the mount members higher than in the past and setting it within a predetermined range, the drive reaction can be achieved without providing an independent torque rod. It was found that the displacement of the power plant due to force can be sufficiently regulated.

  Thus, the invention of claim 1 is such that a power plant in which an engine and a transmission are arranged in series is mounted horizontally so that the longitudinal direction thereof is the vehicle width direction, and is mounted at both ends of the engine side and the transmission side, respectively. An engine mount system that is elastically supported at two points by the mounted mount member and includes a torque rod for restricting the swing of the power plant in the roll direction is assumed.

  The torque rods are integrally provided on the engine-side and transmission-side mount members, and power plant load support points on the engine-side and transmission-side mount members are respectively provided from the roll shafts of the power plant. And the vertical distance between the load support point on the engine side and the roll shaft is set to a predetermined value or more.

  With the above configuration, first, like the three-point pendulum mount of the conventional example (Patent Document 3), the load support points on the two mount members at both ends in the longitudinal direction of the power plant are both intentionally upward from the roll axis. By separating them from each other, two contradictory actions of reducing idle vibration and restricting displacement by driving reaction force can be obtained with a relatively simple configuration in a well-balanced manner.

  Here, when the load support point of the power plant by the mount member is moved away from the roll axis, the displacement amount at the geometric mount member position with respect to the rotation angle of the power plant around the roll axis increases. At the same time, the input load (force) is reduced by this principle. Therefore, if the distance between the load support point and the roll shaft is increased by a predetermined value or more, the rubber of the mount member is provided by the torque rod provided integrally with the mount member. The deformation of the portion can be effectively regulated to ensure the durability thereof easily, and the rolling of the power plant itself can be effectively suppressed by the torque rod.

  Accordingly, it is not necessary to provide a torque rod separately from the mounting member, and the number of fastening points to the power plant body is two, which is the minimum necessary, so that the assembly cost of the automobile can be further reduced, and the engine It is also easy to secure an arrangement space for devices and the like in the room.

  Here, the vertical distance between the support point of the power plant load and the roll shaft in the mount member is specifically, for example, the vertical distance between the engine-side load support point and the roll shaft, the conventional three-point pendulum. Compared with the mount (the one provided with a torque rod separate from the mount member so as to connect the lower end of the power plant to the vehicle body side), it may be set larger by about 60 mm or more (invention of claim 2). . In this way, the total value of the loads input to the two mount members when a driving reaction force acts on the power plant is substantially the same as the total value of the loads input to the two mount members and the torque rod in the three-point pendulum mount. Therefore, the operation of the invention of claim 1 can be obtained with certainty.

  Alternatively, the vertical distance between the power plant load support point and the roll shaft in each of the engine side and transmission side mounting members may be set to approximately 100 mm or more (invention of claim 3). If it carries out like this, it becomes a structure substantially equivalent to the said Claim 2.

  In addition to the configuration of each of the above inventions, when the height of the transmission side load support point is equal to or less than the height of the engine side load support point, the vertical distance between the load support points is set to about 50 mm or less. Is preferable (Invention of Claim 4). In this way, the swing support shaft of the power plant that connects the two load support points on the left and right sides approaches the horizontal, so that the swing support shaft approaches the center axis of the drive reaction torque to the power plant in parallel. Thus, the force applied to the two left and right mount members due to the action of the drive reaction force torque is not greatly biased to one of them, so that the durability of the mount member can be more easily ensured.

  As described above, according to the engine mounting system according to the present invention, torque rods are integrally provided on the mounting members respectively disposed on the left and right sides of the power plant mounted horizontally in the engine room of the automobile, and the mount By setting the load support point of the power plant in the member higher than a predetermined value, a large driving reaction force (torque) was applied to the power plant during sudden acceleration without providing a separate torque rod from the mount member. Sometimes, excessive rolling can be prevented. As a result, the number of fastening points with the vehicle body of the power plant can be reduced to further reduce the assembly cost of the automobile, and the space in the engine room can be easily secured.

  Hereinafter, embodiments of the present invention will be described in detail with reference to the drawings. It should be noted that the following description of the preferred embodiment is merely illustrative in nature, and is not intended to limit the present invention, its application, or its use.

-Mount system configuration-
1 and 2 show a schematic configuration of an engine mount system S according to an embodiment of the present invention. In both figures, a symbol P is a power plant in which an engine 1 and a transmission 2 are coupled in series. This power plant P is mounted horizontally in an engine room of an automobile (not shown) so that its longitudinal direction (the direction in which the crankshaft of the engine 1 extends) is the vehicle width direction. It is elastically supported at two points with respect to the vehicle body side frames 6 and 7 via mount members 3 and 5 respectively disposed at the end portions on the engine 1 side and the transmission 2 side.

  FIG. 1 is a view of the engine 1 with all the intake and exhaust systems and accessories omitted, and only the main body is seen from the upper right side of the rear of the vehicle body, and FIG. The part is seen substantially horizontally from the rear of the vehicle body. As shown in the figure, the main body of the engine 1 is generally composed of a cylinder block 10 and a cylinder head 11 disposed on the cylinder block 10. The longitudinal end opposite to the transmission 2 (the vehicle body shown on the front side in FIG. 1). A belt cover 12 is disposed at the right end), a head cover 13 is disposed above the cylinder head 11, and an oil pan 14 (shown only in FIG. 2) is disposed below the cylinder block 10. Yes. And the lower end side of the engine side mounting bracket 15 is fastened to the right side wall of the cylinder head 11 through the belt cover 12, and the upper end portion of the mounting bracket 15 extending upward therefrom is bent substantially horizontally, so that the engine side It is fastened to the upper part of the mounting member 3 in a state of being superimposed from above. As will be described in detail later, the engine-side mount member 3 is a so-called liquid-sealed mount in this embodiment, and a cylindrical mount main body portion 30 is disposed with its axis line z (see FIG. 3) directed vertically. The mount main body 30 is fastened on the vehicle body side frame 6 by three brackets 31, 31, 31 attached to the lower outer periphery.

  In this embodiment, the transmission 2 is an automatic transmission in which a differential is integrated in addition to a torque converter and a transmission gear train (may be a manual transmission or a CVT), and a bell housing of the transmission case 20 20a is connected to the cylinder block 10 at the crankshaft side end of the engine 1 and drives the front wheels of the automobile from the bulging portion 20b formed at the rear of the bell housing 20a toward the left and right sides, respectively. Drive shafts 22 for extending are extended. The transmission-side mount member 5 is disposed so that the tip end portion of the tapered transmission case 20 is suspended from the side frame 7 on the left side of the vehicle body by the mount bracket 23. A detailed configuration of the transmission-side mount member 5 will be described later.

  In the power plant P in which the engine 1 and the transmission 2 are coupled in series as described above, the engine 1 is taller than the transmission 2 as shown in FIG. R (roll inertia main axis) is inclined downward from the end on the engine 1 side toward the transmission 2 side, as indicated by a one-dot chain line in the figure. The two mount members 3 and 5 that receive the weight of the power plant P are separated from the roll axis R upwardly, and the load support points f1 and f2 of the two mount members 3 and 5 are approximately the same. The same height is set (the engine 1 side f1 is slightly higher than the transmission 2 side f2, but the difference is preferably about 50 mm, for example). Thus, the power plant P can swing like a pendulum around a line segment L (swing support shaft: indicated by a virtual line in the figure) connecting the two load support points f1 and f2. It has become.

  The setting of the heights of the load support points f1 and f2 is a characteristic part of the present invention, and will be described in detail later. The engine mount system S according to this embodiment has the load support points f1 and f2 on the engine side and the transmission side. The vertical distances D1 and D2 between the roll axis R and the roll axis R are both set to a predetermined value (approximately 100 mm) or more. That is, the load rods f1 and f2 of the two mount members 3 and 5 are both separated from the roll axis R by a predetermined amount or more upward, so that the torque rods provided integrally with the mount members 3 and 5 respectively. The effect of 40 and 56 is enhanced so that rolling of the power plant P can be effectively suppressed.

  The vertical distances D1 and D2 between the load support points f1 and f2 and the roll axis R are as shown in FIG. 2 when the power plant P is viewed in the longitudinal direction of the vehicle body. Are the lengths of the legs of the perpendiculars that are respectively lowered to the roll axis R (lengths from the load support points f1 and f2 to the intersections of the perpendicular and the roll axis R). Here, as described above, the roll axis R of the power plant P is inclined downward from the engine 1 side toward the transmission 2 side, and therefore, between the load support point f2 on the transmission side and the roll axis R. Therefore, it is sufficient to set the vertical distance D1 between the load support point f1 on the engine side and the roll shaft R to be equal to or greater than the predetermined value.

-Mount member structure-
Next, the detailed structure of the engine side mount member 3 will be described with reference to FIG. As shown enlarged in the figure, the mount main body 30 of the engine-side mount member 3 includes a substantially cylindrical metal casing 32 arranged so as to extend in the vertical direction, and a round opening at a substantially central portion on the upper surface thereof. And a connecting fitting 34 supported by the rubber elastic body 33 in a state of being inserted into the hole from above. The lower portion of the connecting metal fitting 34 is accommodated in the casing 32 and bonded to the upper portion of the rubber elastic body 33, while the upper portion is a shaft portion 34 a that extends upward from the upper surface of the casing 32. The lower surface of the bent portion of the engine side mounting bracket 15 is joined to the upper end surface of the shaft portion 34a, and both are fastened by the mounting bolt 35. That is, a bolt hole is drilled in the shaft portion 34a from the substantially central portion of the upper end surface thereof downward along the axis line z, and the mount bracket 15 is attached by the mounting bolt 35 screwed into the bolt hole. And the connection fitting 34 are fastened.

  On the other hand, an inverted conical supported portion 34b is formed in the lower portion of the connecting bracket 34. The supported portion 34b has an inverted conical shape that is gradually expanded downward from the lower end portion of the shaft portion 34a and then gradually sunk downward. A rubber elastic body 33 is provided between the supported portion 34a and the casing 32 facing the outer periphery thereof. That is, a mortar-shaped concave portion is formed on the upper inner peripheral side of the rubber elastic body 33, and the peripheral surface of the concave portion is attached to the outer peripheral surface of the supported portion 34b of the connection fitting 34. The elastic body 33 is formed in a substantially truncated cone shape so as to radiate outward from the entire lower side of the coupling metal 34 and extend obliquely downward, and the outer peripheral surface of the lower portion thereof is the casing 32. It is bonded to the inner peripheral surface of the lower part of the. Accordingly, the connecting fitting 33 is supported from below by the casing 32 via the rubber elastic body 33.

  As described above, the lower portion of the rubber elastic body 33 adhered and fixed to the lower portion of the casing 32 has a cylindrical shape that opens downward, and the relatively upper portion thereof is formed thick. On the other hand, the relatively lower portion is a thin layer portion made of a rubber film. An orifice plate 36 is press-fitted into the inner peripheral side of the thin layer portion from below, and a rubber diaphragm 37 is disposed from below to cover the entire lower portion of the orifice plate 36, whereby a rubber diaphragm 37 is disposed. A lower end opening of the elastic body 33 is liquid-tightly closed, and a cavity is formed inside. The diaphragm 37 is caulked by a bent portion at the lower end of the casing 32 in a state where an annular reinforcing plate 38 is embedded in a relatively thick outer peripheral portion, and this portion is superimposed on the outer peripheral portion of the orifice plate 36 from below. It has been.

  As described above, a buffer solution such as ethylene glycol is sealed in the cavity section defined in the rubber elastic body 33 so that the vibration of the power plant P input to the rubber elastic body 33 is absorbed and alleviated. This is the liquid chamber F. The inside of the liquid chamber F is divided into upper and lower portions by the orifice plate 36, and the upper side thereof is a pressure receiving chamber whose volume is enlarged or reduced with the deformation of the rubber elastic body 33, and the lower side is The volume is expanded or contracted by the deformation of the diaphragm 37, so that an equilibrium chamber is formed that absorbs the volume variation in the pressure receiving chamber. That is, on the outer periphery of the orifice plate 36, an orifice passage 39 having a double spiral shape is formed between the thin rubber layer 33 of the rubber elastic body 33 bonded to the inner periphery of the casing 32, and this orifice passage. The upper end of 39 opens to the pressure receiving chamber on the upper side of the liquid chamber F, while the lower end of the orifice passage 39 opens to the equilibrium chamber on the lower side of the liquid chamber F. The low-frequency vibrations acting on the pressure receiving chamber from the rubber elastic body 33 are damped by passing through the orifice passage 39.

  In addition to the above basic configuration, the mount member 3 is integrally provided with a torque rod 40 for restricting the swing of the power plant P in the roll direction. That is, the casing 32 of the mount main body 30 is provided with stays 41 and 41 made of two plate members parallel to each other so as to extend toward the rear of the vehicle body. A torque rod 40 is disposed between the mount main body 30 and the connection fitting 34 so as to extend in the longitudinal direction of the vehicle body. More specifically, the stays 41, 41 are formed by forming a steel plate in a substantially J shape by press molding, for example, and the lower ends thereof are welded to the outer periphery of the casing 32 of the mount main body 30. The upper ends are arranged side by side on the right side of the shaft 34a of the connection fitting 34, that is, at a position substantially horizontally away from the rear of the vehicle body.

  Further, the torque rod 40 is provided with thick disk-like connecting portions 43 and 44 at both ends of the rod member 42, respectively, and they are rotated and displaced by 90 ° around the axis of the rod member 42. Become. The connecting portion 43 at the front end is formed by elastically connecting an outer cylinder portion 43a integrally provided at the front end of the rod member 42 and an inner cylinder portion 43b positioned coaxially with an annular rubber bush 43c. The inner cylinder portion 43c is externally inserted into the shaft portion 34a of the connecting metal fitting 34, and is coupled in an externally fitted state. On the other hand, the connecting portion 44 toward the rear end is provided with an outer cylinder portion 44a, an inner cylinder portion 44b, and a rubber bush 44c at the rear end portion of the rod member 42 in the same manner as the front end connecting portion 43. 44b is disposed so as to be sandwiched between the stays 41 and 41 with the axis centered in the left-right direction, and is fixed by fastening with mounting bolts 45 and nuts 16 penetrating through the round holes formed in the stays 41 and 41. .

  When vibration with a relatively small amplitude occurs around the roll axis R of the power plant 9 as in, for example, idling operation of the engine 1, this vibration is caused by bending of the rubber bushes 43c and 44c of the connecting portions 43 and 44. It is not absorbed and transmitted to the vehicle body side via the torque rod 40. On the other hand, if the power plant P tries to rotate around the roll axis R due to the driving reaction force (torque), the rubber bushes 43c, 44c bend to the maximum extent, and then the connecting bracket 34 on the power plant P side and the vehicle body side The torque rod 40 receives the drive reaction force between the mount main body casing 32 and the displacement of the power plant P beyond that. In the illustrated torque rod 40, the rubber bush 44c of the rear end connecting portion 44 is provided with a curb so that it can absorb idle vibration more effectively, but this is not restrictive.

  Next, the structure of the transmission-side mount member 5 is shown in an enlarged manner in FIG. 4. This is because the upper end portion of the mount bracket 23 extending upward from the front end side of the transmission 2 is used as the vehicle body side frame. 7 is suspended through a rubber block 51 by a metal frame member 50 attached to the 7 side. That is, the frame member 50 is formed by, for example, press-molding a steel plate or the like, and integrally forming a rectangular frame-shaped main body portion 52 and a stay portion 53 extending therefrom toward the rear side of the vehicle body (the left side in the figure). Further, flange portions 54 and 54 are provided on the side of the main body portion 52 by welding another steel plate piece and extending respectively on the side and the lower side, and the vehicle body side frame 7 is attached to the flange portions 54 and 54 by mounting bolts (not shown). To be concluded.

  Further, a standing wall portion 52b is integrally formed on the main body portion 52 of the frame member 50 by drawing or the like so as to extend upward from the periphery of the opening portion 52a so as to surround four sides of the vertical axis z. A metal connecting pipe 55 is supported by a rubber block 51 having both left and right ends bonded to 52b so that its axial center is vertically movable. That is, the connecting pipe 55 is integrally vulcanized and molded so that the lower portion thereof has a relatively small diameter, for example, by drawing, and is embedded in a substantially central portion of the rubber block 51 except for the small diameter portion 55a. Do it. Then, the stud bolt 24 of the mount bracket 23 is inserted into the small diameter portion 55a of the connecting pipe 55 from below, and the nut 25 is screwed into the stud bolt 24 from above, so that the mount bracket 23 and the connecting pipe 55 are Is concluded.

  Further, a torque rod 56 is also provided integrally with the transmission-side mount member 5. That is, the front end (rear end) of the stay portion 53 extending rearward from the main body portion 52 of the frame member 50 is bent downward at a substantially right angle, and the bent portion 53a is bent as described above. The connecting pipe 55 connected to the main body 52 is located just behind the small-diameter portion 55a of the connecting pipe 55, that is, at a position substantially horizontally behind the vehicle body. A torque rod 56 is disposed between the stay bent portion 53a and the small diameter portion 55a of the connecting pipe 55 so as to extend in the longitudinal direction of the vehicle body.

  This torque rod 56 is provided with connecting portions 58 and 59 with rubber bushes 58a and 59c interposed at both ends of a rod member 57, respectively, as in the engine side. 59 is composed of an outer cylinder part 59a, an inner cylinder part 59b, and a rubber bush 59c as in the engine side, and the inner cylinder part 59b is externally inserted into the small diameter part 55a of the connecting pipe 55 and coupled in an externally fitted state. Has been. On the other hand, the connecting portion 58 on the front end side of the torque rod 56 is different from the other connecting portions 43, 44, 59 in that a stay is provided between the two ring-shaped rubber bushes 58 a, 58 a skewered at the tip of the rod member 57. The bent portion 53a is sandwiched and fixed.

  That is, a circular flange 58b is integrally formed on the front end side of the rod member 57 of the torque rod 56, and the tip of the flange 58b penetrates a round hole formed in the bent portion 53a of the stay 53. The rubber bush 58a is sandwiched between the bent portion 53a and the flange portion 58b. Further, another rubber bush 58a and a washer 58c are disposed on the distal end side of the rod member 57 extending forward of the vehicle body from the bent portion 53a, and a small-diameter screw portion 57a is disposed at the distal end portion of the rod member 57. When the washer 58c is fastened to the tip of the rod member 57 by a nut 58d that is screwed into the screw portion 57a, the rubber bush 58a is sandwiched between the washer 58c and the bent portion 53a. ing.

  Thus, even in the transmission-side mount member 5 having the above-described configuration, the idle vibration of the engine 1 is absorbed by the bending of the rubber bushes 58a and 59c, so that it is transmitted to the vehicle body side via the torque rod 56. On the other hand, when a large driving reaction force is applied, the rotational displacement about the roll axis R of the power plant P is caused by the torque rod 56 between the connecting pipe 55 on the power plant P side and the frame member stay 53 on the vehicle body side. Be regulated.

-Effect-
Next, the operation and effect of the engine mount system S configured as described above will be described. First, in the power plant P mounted on the automobile, when the engine 1 is in an extremely low speed operation state such as an idle operation, the torque fluctuation occurs. The resulting low frequency vibration occurs around the roll axis R. At this time, in the mount main body 30 of the engine-side mount member 3, the power plant P-side coupling fitting 34 vibrates slightly back and forth with respect to the vehicle body-side casing 32, and similarly, the transmission-side mount member 5 also has the power plant. The connecting pipe 55 on the P side slightly vibrates back and forth with respect to the frame member 50 on the vehicle body side. This vibration is of a low frequency and has a very small amplitude. Will be absorbed by the vehicle, and there will be very little transmission to the car body. Further, the idle vibration is also absorbed by the torque bushes 43c, 44c, 58a, and 59c in the torque rods 40 and 56 of the both mount members 3 and 5, so this vibration is transmitted to the vehicle body side via the torque rods 40 and 56. It is not transmitted to.

  On the other hand, when a large driving reaction force (torque) is applied, for example, when the vehicle is suddenly accelerated or decelerated, the power plant P is generally arranged on the roll axis R as schematically shown by a white arrow in FIG. As a whole, it swings back and forth like a pendulum about the upper swinging support shaft L while rotating (rolling) around. At this time, the rotational displacement around the roll axis R is effectively suppressed by the reaction force applied mainly from the torque rods 40 and 56 of the left and right mount members 3 and 5, and the power plant P as a whole in the front-rear direction. As for the shaking, the mass of the power plant P serves as an inertial body that suppresses the shaking. For this reason, the displacement of the power plant P due to the driving reaction force does not become excessive.

  Specifically, in this respect, the load support points f1 and f2 of the power plant P by the left and right mounting members 3 and 5 are rolled as in the engine mount system S of this embodiment and the three-point pendulum mount of the conventional example (Patent Document 3). In the case of intentionally separating upward from the axis R, if the interval is increased, the displacement amount at the positions of the mount members 3 and 5 with respect to the rotation angle of the power plant P around the roll axis R is geometrically large. At the same time, the input load to the mount members 3 and 5 is reduced by the lever principle. In other words, as the load supporting points f1 and f of the mount members 3 and 5 are separated from the roll axis R, the arm of the moment generated around the roll axis R of the power plant P by the reaction force from the mount members 3 and 5 becomes longer. Thus, the effectiveness of the torque rods 40 and 56 provided on the mount members 3 and 5 is improved, and the rolling of the power plant P can be effectively suppressed.

  Therefore, as in this embodiment, the vertical distance between the load support points f1 and f2 of the engine side and transmission side mount members 3 and 5 and the roll shaft R are both set to be larger than a predetermined value, and the If the torque rods 40 and 56 are integrally provided on each of the two mount members 3 and 5, separately, independent torque rods Tr such as a conventional three-point pendulum mount (shown by phantom lines in FIG. 5). It is considered that the displacement of the power plant P due to the driving reaction force can be sufficiently suppressed even without providing.

  Hereinafter, in the two-point engine mount system S of this embodiment, while changing the vertical distance between the load support points f1, f2 of the left and right mount members 3, 5 of the power plant P and the roll axis R, the power Experimental results (examples) of examining changes in input loads applied to the two mount members 3 and 5 by the driving reaction force acting on the plant P are shown as a comparative example of a conventional three-point pendulum mount. In this experiment, when the engine 1 generates the maximum torque, a torque corresponding to the reaction force of the driving torque applied to the driving wheels of the automobile at a predetermined gear ratio (for example, a gear ratio corresponding to the first speed to the second speed) is applied. Although applied to the drive shaft, the same magnitude of torque may be applied directly around the roll axis R of the power plant P. Further, in the three-point pendulum mount of the comparative example, as shown by the phantom line in FIG. 5, the independent torque rod Tr that connects the lower end portion of the power plant P to the rear vehicle body side is provided. The member is not provided with a torque rod.

  The result of the experiment is as shown in FIG. 6. In FIG. 6A, “X” is the total (Total) of input loads in the longitudinal direction of the vehicle body (X direction) in the mount members 3, 5, etc. Similarly, “Y, Z” is the sum of the input loads in the vehicle width direction and the vertical direction, respectively. In both the engine mount system S of the example and the three-point pendulum mount of the comparative example, the total value of the input loads to the mount members 3, 5 and the like mainly reflects the direction of the driving reaction force (X). It has become.

  The graph of FIG. 5B shows how the input load X in the front-rear direction changes when the support points of the left and right mount members 3 and 5 are raised. That is, in the two-point mount of the embodiment, when the support height of the left and right mount members 3 and 5 is the same as the three-point mount of the comparative example (height UP = 0), the input of the two mount members 3 and 5 The total load is larger than the total input load applied to the two mount members of the comparative example and the separate torque rod. From this, it can be seen that the displacement of the power plant P becomes relatively large.

  On the other hand, if the support height of the left and right mounting members 3 and 5 is increased (UP) in the two-point mounting system of the embodiment, the total value of the input load decreases approximately in inverse proportion to this. It can be seen that the value is substantially the same as that of the three-point mount of the comparative example at the time of 60 mm up. Therefore, in the engine mount system S of the above-described embodiment, the heights of the load support points f1 and f2 of the left and right mount members 3 and 5 are aligned so that the difference between them is not so large, and the load on the engine side The vertical distance D1 between the support point f1 and the roll axis R is set to a conventional three-point pendulum mount (a torque rod separate from the mount member is provided so as to connect the lower end of the power plant to the vehicle body side) ), The rolling of the power plant P can be regulated to the same extent as before.

  Further, according to the experimental result, it is understood that the total value of the input load is further reduced by further increasing the support height of the left and right mount members 3 and 5 beyond 60 mm. However, the fact that the load support points f1 and f2 of the power plant P by the mount members 3 and 5 are far away from the roll axis R is not preferable for the reduction of idle vibration, so that the left and right mount members 3 and 5 are supported. The height should not be too large. Therefore, for example, when the individual input load values for each of the mount members 3 and 5 are examined when the distance is 120 mm up, this is as shown in the bar graph of FIG. 7. At this time, the total value of the longitudinal input loads is compared. It becomes smaller than the three-point mount of the example, and it can be seen that the input load falls within a range that is not much different from the case of the three-point mount even when viewed from the left and right mount members 3 and 5 alone.

  Therefore, from the above experimental results, in the engine mount system S of this embodiment, the vertical distances D1, D2 between the power plant load support points f1, f2 and the roll axis R in the left and right mount members 3, 5 are determined. In comparison with a three-point pendulum mount as in the conventional example (Patent Document 3), it is preferable to set the height approximately 60 mm or higher, and it is more preferable to set a range higher by about 100 to 120 mm, for example.

  In order to optimally set the height of the load support points f1 and f2 of the left and right mount members 3 and 5, in the engine mount system S of this embodiment, the load support points f1 and f2 and the roll The vertical distances D1 and D2 (particularly D1) from the axis R are set to be equal to or greater than the predetermined value described above.

  Therefore, according to the engine mount system S according to this embodiment, the torque rods 40 and 56 are integrally provided on the two mount members 3 and 5 that support the power plant P at both longitudinal ends thereof, respectively, Since the load support points f1 and f2 of the power plant P by both the mount members 3 and 5 are set higher than before and set within a predetermined optimum range, there is no need to provide an independent torque rod Tr separately from them. The rolling of the power plant P due to the driving reaction force can be sufficiently restricted, and the durability of the mount members 3 and 5 can be ensured.

  If it is not necessary to provide a separate torque rod in addition to the two left and right mounting members 3 and 5 required to support the power plant P, the power plant P is fastened to the vehicle body. Since there are two places, it is possible to further reduce the assembly cost in the automobile assembly line as compared with the prior art, and it is easy to secure an arrangement space for equipment and the like in the engine room.

(Other embodiments)
The configuration of the present invention is not limited to the above embodiment, but includes various other configurations. That is, in the above-described embodiment, the engine-side mount member 3 is a liquid-sealed type. However, the present invention is not limited to this. For example, the static load may be supported only by the rubber elastic body 33, or the transmission The mounting member 5 on the side may be a liquid seal type. Not only this point but the support structure of the vertical direction load in the mount members 3 and 5 may be anything.

  In the above-described embodiment, the torque rods 40 and 56 having the rod members 42 and 57 in the two mount members 3 and 5 are arranged at the rear of the vehicle body at the load support points f1 and f2, respectively. However, the present invention is not limited to this. For example, the torque rod may be disposed in front of the vehicle body at the load support points f1 and f2 to receive the driving reaction force in the pulling direction. The torque rod may be disposed on the left or right of the mount main body 30 or may be above or below the mount body 30.

It is a perspective view which shows schematic structure of an engine mount system. FIG. 2 is a view corresponding to FIG. 1 when the power plant is viewed straight from the rear of the vehicle body. It is an enlarged view which shows the structure of an engine side mount member, (a) is a top view, (b) is a left view. FIG. 4 is a view corresponding to FIG. 3 for a transmission-side mount member. It is explanatory drawing which mainly shows the positional relationship of a load support point and a roll axis | shaft seeing a power plant from the vehicle body left side. (a) is a list of experimental results obtained by examining changes in the input load due to the driving reaction force while changing the support height of the mount member, and (b) is a graph thereof. It is a bar graph which shows the input load for every mount member in predetermined support height.

Explanation of symbols

S engine mount system P power plant 1 engine 2 transmission 3 engine side mount member 5 transmission side mount member 40, 56 torque rod f1, f2 load support point R roll shaft

Claims (4)

A power plant in which the engine and transmission are arranged in series is mounted horizontally so that its longitudinal direction is in the vehicle width direction, and elastic at two points by the mounting members respectively disposed at both ends on the engine side and transmission side In an engine mount system provided with a torque rod for supporting and regulating swinging of the power plant in the roll direction,
The torque rods are integrally provided on the engine side and the transmission side mount members, respectively.
The power plant load support points on the engine side and transmission side mount members are spaced above the roll shaft of the power plant, respectively, and at least between the load support point on the engine side and the roll shaft. An engine mount system characterized in that the interval is set to a predetermined value or more.   The vertical distance between the engine-side load support point of the power plant and the roll shaft is compared to the case where a torque rod separate from the mount member is provided so as to connect the lower end of the power plant to the vehicle body side, 2. The engine mounting system according to claim 1, wherein the engine mounting system is set to be larger than about 60 mm.   2. The engine mount system according to claim 1, wherein the vertical distance between each load support point on the engine side and the transmission side and the roll shaft is set to approximately 100 mm or more. 2. The height of the transmission-side load support point is equal to or less than the height of the engine-side load support point, and the vertical distance between the load support points is set to about 50 mm or less. Engine mounting system of any one of ~ 3.

Images