JP3243746B2 - Torsion damper - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a torsional damper for reducing vibration of a torque converter.

[0002]

2. Description of the Related Art A conventional example of a torsional damper for a torque converter of this type is disclosed, for example, in Japanese Utility Model Laid-Open No. 58-144146. In this conventional example, as shown in a longitudinal sectional view of FIG. 20, a hub arm 32 is fixed to a crankshaft 31 of an engine by bolts 33, and is formed of two hub cases 34a and 34b on both sides of a hub portion 32a of the hub arm 32. The hub case 34 is fixed to the hub portion 32a with a rivet 35 so that a gap is formed with respect to the hub portion 32a, and the hub arm 32 and the torsion spring 36 are inserted into the hub cases 34a and 34b while being partitioned by the separator 37, and A ring gear 38 is fixed to the outer periphery of the outer peripheral annular portion 32b of 32,
Bolt the end of the hub case 34a close to the torque converter.
The converter cover 40 is connected to the converter cover 40, and the hub portion 40a of the converter cover 40 is fitted to a thrust receiving surface 32c provided on the hub arm 32. In this conventional example, the rotational force of the crankshaft 31 is
2. The power is transmitted to the converter cover 40 through the torsion spring 36 and the hub case 34 in this order.

[0003]

In the conventional torsion damper, when the engine is started (when the starter motor starts to operate), the gradually increasing engine speed matches the resonance speed of the torsional damper. When passing through the point, torque fluctuation of a large amplitude occurs in the torsional damper as shown in FIG. 21 (b), and this torque fluctuation affects the durability of the torsion damper body.
As a countermeasure, it is conceivable to suppress the level of torque fluctuation at the resonance point by providing a damping element using viscosity or the like, but in that case, the structure becomes complicated, so that a core stop, an increase in weight, etc. are caused. Regardless, as shown in FIG. 22, at the time of lock-up, in the practical range where the engine speed exceeds the resonance speed, the vibration reduction effect is lower than when no damping element is provided, so that a good vibration reduction effect is obtained. You will not be able to do it.

SUMMARY OF THE INVENTION The present invention solves the above-mentioned problems by providing a structure that can improve the durability of a torsional damper at the time of engine start and ensure the effect of reducing vibration in the engine speed range. Aim.

[0005]

For this purpose, a torsion damper according to the present invention has the following features.
A torsion damper that includes a driving member coupled to the engine output shaft, a ring gear fixed to the driving member, and a driven member coupled to the torque converter, and that is drivingly coupled between the engine and the torque converter; A synchronous meshing means for meshing with the starter motor pinion in synchronization with the ring gear when the starter motor is operated is provided on the driven member, and in the configuration of claim 3, the engine crank end is connected to the engine crank end via a torsional damper. A part of the torque converter, which is drivingly coupled to the engine crank end, is rotatably fitted in the engine crank end, and a rotational vibration damping element for providing resistance to the relative rotation is disposed in the fitted portion. Viscous flow so that the damping characteristics of the vibration damping element are almost the same when the viscous fluid is cold and hot Shape varies with temperature and is characterized in that a shape change element.

[0006]

According to the first aspect of the present invention, when the starter motor starts operating at the time of starting the engine, the starter motor pinion first enters the ring gear fixed to the driving member connected to the engine output shaft to mesh therewith. Then, it also enters and meshes with the synchronous meshing means provided on the driven member connected to the torque converter, thereby drivingly coupling the engine and the torque converter. Such a synchronous meshing state continues until the starter motor is turned off, during which the engine speed exceeds the resonance speed of the torsional damper. No phenomenon occurs, and the durability of the torsional damper is improved. Further, after the above-mentioned synchronous meshing state is released, the function as a damping element hardly occurs in a practical range where the engine speed exceeds the resonance speed, and a good vibration reduction effect during lock-up operation can be obtained. In the above, it is more preferable that the synchronous meshing means be a ring gear having tapered teeth formed in the starter motor pinion entry direction, for example, as described in claim 2 because entry of the starter motor pinion becomes easy.

According to a third aspect of the present invention,
A part of the torque converter that is drivingly coupled to the engine crank end via a torsional damper is disposed in a fitting portion that is rotatably fitted into the engine crank end. Since the shape changing member that changes its shape in accordance with the temperature change is provided, the shape changing member changes the damping characteristic of the rotational vibration damping element that gives resistance to the relative rotation substantially at the time of the low temperature and the high temperature of the viscous fluid to change the temperature. It is possible to realize a stable damping characteristic that is not affected, suppress the level of torque fluctuation at the time of passing the resonance point at low temperature of the viscous fluid, improve the durability of the torsional damper, and rotate the engine at high temperature of the viscous fluid. In the practical range where the number exceeds the resonance speed, there is almost no effect as a damping element and good vibration reduction during lock-up operation It is effective.

[0008]

Embodiments of the present invention will be described below in detail with reference to the drawings. FIG. 1 is a longitudinal sectional view showing the structure of a first embodiment of the torsion damper of the present invention. In the drawing, reference numeral 11 denotes a hub arm as a driving member.

The hub arm 11 is provided with a bolt 5 on the shaft end of the crankshaft 1 of the engine using the hub portion 11a as an output shaft.
A ring gear 13 is fixed to the outer periphery of the outer peripheral annular portion 11b by welding or the like. Also, a hub case 16 as a driven member composed of two hub cases 16a and 16b is fitted to the hub arm 11 by fixing the space between the hub arms 11 and 16b with rivets 18 so as to form a fixed gap with the hub arm 11. The outer periphery of the hub case 16a has bolts 6
The converter cover 2 is fastened and connected to the converter cover 2, and the converter cover 2 is connected to a pump impeller of a torque converter (not shown).

A torsion spring 15 is further inserted into the hub arm 11 as shown in FIG. That is, three spider portions 11c radially extending from the hub portion 11a are formed on the hub arm 11 and are spaced apart from each other in the circumferential direction. Separators 14 radially extending from the hub portion 11a are interposed between the spider portions 11c. The spider portion 11c and the separator 14 define six spring insertion spaces. A coiled torsion spring 15 is interposed in each of these spring insertion spaces to form three sets of series spring structures, and these torsion springs are engaged with rectangular windows 17 opened in hub cases 16a and 16b. . Hub part 2a of converter cover 2
In order to receive the thrust, a thrust receiving surface 12 is formed on the hub portion 11a to receive an axial thrust force of the torque converter.

The torsion damper of the present embodiment, which connects between the crankshaft 1 and the converter cover 2 as described above, functions as a vibration reduction device as described below. That is, when the crankshaft 1 of the engine is driven, the hub arm 11 fixed to the crankshaft rotates integrally with the crankshaft 1. As a result, the rotation force including the rotation fluctuation of the engine
The rotation is transmitted to the torsion spring 15 via the gear 11, and the rotational fluctuation of the engine is absorbed there (the rotational fluctuation of the engine is also absorbed to some extent by the inertia of the ring gear 13). This torque is transmitted to the hub case 16 (16a, 16b) as a driven member via the torsion spring 15, and the hub case 16a is connected to the converter cover 2 by the bolt 6, so that the torque is applied to the hub case 16a. The vibration is further transmitted to the torque converter (not shown) through the converter cover 2, and a desired vibration reduction effect is obtained during the transmission.

In this embodiment, the hub case 16a
Is extended in the outer peripheral direction, and its end is bent so as to be parallel to the axis to form a flange portion, and the ring gear 20 is fixed to the outer periphery of the flange portion by welding or the like. As shown in FIG. 3 which is an arrow B view of FIG. 1, the start direction of the pinion gear of the starter motor (not shown) is such that the starter motor automatically enters at the time of start and automatically escapes after the start as shown in FIG. The tapered teeth 20a are formed with respect to the direction (from left to right in the figure), thereby facilitating entry and exit of the pinion gear. This ring gear
Reference numeral 20 denotes a ring gear fixed to the hub arm 11, which is a driving member.
Since the starter motor pinion enters at the time of startup, the ring gears 13 and 20 are meshed synchronously with each other, and the ring gear 20 is fixed to the hub case 16a which is a driven member. The crankshaft 1 of the engine and the torque converter cover 2 are integrally connected so that no relative displacement occurs between them. At that time, the ring gear 20 functions as a synchronous meshing means.

Next, the operation of the present embodiment will be described in comparison with the conventional example. First, in the conventional torsion damper, when the engine is started and a predetermined vibration force is input from the engine, the entire system is schematically shown in FIG.
A torsional stiffness K and a clutch with a damping rate C are arranged in parallel between an engine inertia (inertia rotating object) and a torque converter inertia. The torque fluctuation shows a peak value at a predetermined engine speed as shown in FIG. Thus, as shown in FIG. (C), the starter motor starts to operate instantaneously t ₀ passes through the resonance rotational speed instantaneously t ₁ the engine speed gradually increases and, instantaneously t ₁ subsequent torsional damper A large-amplitude torque fluctuation (which has a natural frequency of the damper body) occurs, and this torque fluctuation may cause deterioration of durability of the torsional damper, generation of abnormal noise, and the like.

On the other hand, in the torsion damper of the present embodiment, when the starter motor is not operated, the model of the entire system is shown in FIG.
As shown in Fig. 4 (a), when the starter motor is operating, the model of the entire system is expressed as a direct connection between the engine inertia and the torque converter inertia by locking the torsional damper as shown in Fig. 4 (a). The torque fluctuation of the torsion damper at that time is the same as that when the torsion damper does not act at all until the engine speed Nx when the starter motor is turned off is reached, as shown by the solid line in FIG. The torque fluctuation becomes zero. Thus, as shown in FIG. (C), after passing through the resonance rotational speed the engine rotational speed is gradually increased to the starter motor starts to operate instantaneously t _0, OFF the starter motor instantaneously t ₂
By disengaging the starter motor pinion, the torque fluctuation of the torsion damper becomes a low level in which the large amplitude portion of the conventional example is cut. As a result, the durability of the torsional damper is improved, and no abnormal noise is generated when the engine is started.

FIG. 5 shows a first embodiment of the torsion damper of the present invention.
FIG. 2 is a longitudinal sectional view showing a configuration of a reference example, and the same parts as those in the first embodiment of FIG. 1 are denoted by the same reference numerals. In the first reference example, the portion of the torsion damper is replaced with the conventional example (actually disclosed in
-144146), and a portion of the adjacent torque converter with a lock-up mechanism is similar to that of Japanese Patent Application Laid-Open No. 3-51575 (Japanese Patent Application No. 1-184981) previously filed by the present applicant. And a clutch (clutch means) 21 for generating a hysteresis torque is provided between them (for details of both the above-mentioned parts, refer to the above-mentioned references, respectively). That is, the clutch 21 is connected to the converter cover 2
And a clutch facing 21b fixed to the left end face of the cone clutch in the drawing, and a working surface 22 corresponding to the clutch facing 21b is formed on the hub portion 11a of the hub arm 11. ing. The torsion damper of the present embodiment is configured such that an axial clearance as shown is formed between the paired hub cases 16a and 16b and the hub portion 11a of the hub arm 11.

[0016] Figure 6 is a circuit diagram of a hydraulic circuit used in the first reference example, the hydraulic circuit is always predetermined pressure to the line pressure P _L in the hydraulic circuit of JP above Japanese Patent Application 1-184981 (about 4k
g / cm ² ), and a pressure control solenoid for the pressure reducing valve 122 which is supplied as the converter supply pressure Pc.
This is a modification in which the converter supply pressure Pc can be variably controlled by adjusting the exciting current to the computer 122b by the computer 122b. In this hydraulic circuit, the computer 122b performs hysteresis torque control that controls the hysteresis torque (friction torque) generated by the clutch 21 according to the present embodiment in accordance with the engine speed and the lock-up operation state of the torque converter as described below. carry out.

That is, based on a command from the computer 122b, the converter supply pressure Pc is controlled to the characteristics shown in FIG. 7 according to the region to which the engine speed belongs. Here, when the lock-up is not activated, if the engine speed is in the extremely low rotation range of O to A, Pc is rapidly increased to the maximum pressure Pmax due to the rise characteristic of the hydraulic pressure as shown in FIG. AB where rotation speed exists
In the idling rotation region of B to C where the idling rotational speed exists, since the resonance rotational speed has been passed, the Pc is kept at the maximum pressure Pmax in the region of FIG. The pressure gradually decreases until the pressure reaches Pmin, and if it exceeds C, Pc is reduced to the minimum pressure Pmin
Keep as is.

When the converter supply pressure Pc is controlled to have such characteristics, the hysteresis torque acting between the crankshaft of the engine and the torque converter by the clutch 21 is as shown in FIG. That is, when the torsional damper of the present embodiment is drivingly connected between the engine and the torque converter, the product of this Pc and the inner diameter area S of the torque converter sleeve 117 is determined by the converter supply pressure Pc supplied to the converter chamber 114. Represented by
It receives a thrust F in the axial direction indicated by the left arrow in FIG. 5 (F = Pc × S). The thrust F pushes the clutch facing 21b on the left end of the cone clutch 21a of the clutch 21 against the working surface 22 provided on the hub arm 11, and generates a hysteresis torque acting between the crankshaft of the engine and the torque converter. The larger the value is, the larger the damping element acts on the torsion damper body.

Therefore, when the converter supply pressure Pc is changed as shown in FIG. 7, in the region A to B including the resonance speed of the torsional damper at the time of non-lockup,
Since Pc is maintained at the maximum pressure Pmax, a large hysteresis torque as shown by the solid line in the torsion characteristics of the torsional damper shown in FIG. 8 is obtained. This large hysteresis torque causes the clutch 21 to act as a damping element when the engine is started, thereby suppressing the level of torque fluctuations when the torsional damper passes through the resonance speed, so that the durability of the torsional damper can be improved as desired. it can. The large hysteresis torque is gradually reduced in accordance with an increase in the engine rotation speed in the idling rotation range of B to C after passing the resonance rotation speed, and Pc is kept at the minimum pressure Pmin in a range exceeding C. Since a small hysteresis torque as shown by a dotted line in FIG. 8 is obtained, energy loss of the hydraulic circuit can be prevented.

On the other hand, at the time of lock-up, as shown by the dotted line in FIG. 8, the converter supply pressure Pc is maintained at a considerably lower pressure than at the time of non-lock-up at a lock-up operation engine speed D or higher. Converter supply pressure Pc is the lock-up control pressure P _{L / C} , Fig. 6
Is the resultant pressure determined by the resistance of the orifice 116 and the oil cooler 123). The hysteresis torque obtained by this Pc becomes extremely small as shown by the solid line in FIG. 8, so that it has almost no effect as a damping element in a practical range where the engine speed exceeds the resonance speed, and excellent vibration reduction at lock-up. The effect is obtained.

The structure of this embodiment has a simpler structure than the conventional case in which a damping element utilizing viscosity or the like is added, hardly causes an increase in cost and weight, and further increases the axial dimension. It has the advantage of not being let.

FIG. 9 shows a second embodiment of the torsion damper of the present invention.
FIG. 2 is a longitudinal sectional view showing a configuration of a reference example, and the same parts as those in the first embodiment of FIG. 1 are denoted by the same reference numerals. In the second reference example, the portion of the torsion damper is the same as that of the conventional example (shown in
58-144146), and a portion of the adjacent torque converter with a lock-up mechanism is configured in the same manner as Japanese Patent Application No. 1-184981, filed by the applicant of the present invention, and a hysteresis between the two. A multi-plate clutch (clutch means) 130 for generating torque is provided (for details of both parts, see the above-mentioned references, respectively).

That is, as shown in FIG. 9 and FIG. 10 which is a detailed view of the clutch part, the multi-plate clutch 130 comprises a clutch hub 131 integrally formed with a hub part 11a directly connected to the crankshaft 1 of the engine. A clutch case 132 integrally formed with the converter cover 2 and a piston 133 slidably fitted on the inner periphery of the clutch case 132
And oil seals 135 and 136 for storing the clutch operating pressure _PCL in an oil chamber 134 inside the clutch.
0, snap rings 137 and 138 for fixing each plate to be described later to the clutch case 132, a drive plate 139 that is spline-engaged with the clutch hub 131, and a drive plate 139 that is spline-engaged with the clutch case 132.
Drive plate and retaining plate 141, which are in frictional contact with each other, and drive plate inserted between snap ring 137 and retaining plate 141
Disc spring 1 for pressing and pressing 139 and driven plate 140
42 (these positional relationships are shown in an exploded perspective view of FIG. 11). The oil chamber 134 is provided with an oil passage 132a provided in the clutch case 132 and an oil passage provided in the converter cover 2.
The lock-up control chamber 143 communicates with the lock-up control chamber 143 via 2b, and the lock-up operating pressure P _{LU in} the lock-up control chamber guided through these oil passages becomes the clutch operating pressure _PCL .

[0024] The hydraulic circuit for supplying the clutch actuating pressure P _CL to the oil chamber 134, but using the same as the first reference example of FIG. 6, the exciting current to the pressure control solenoid 122a in its hydraulic circuit The hydraulic pressure variably controlled by adjusting by the computer 122b is the converter supply pressure.
Change from Pc to the clutch working pressure _{P CL.} In this hydraulic circuit, the computer 122b
Hysteresis torque control for controlling the hysteresis torque (friction torque) at which 0 occurs according to the engine speed and the lock-up operation state of the torque converter as described below is performed.

Although the same hysteresis torque as that of the first embodiment is obtained by the hysteresis torque control, the operation at the time of stopping the engine and the like is different from that of the first embodiment. That is, in an extremely low engine speed range such as when the engine is stopped or when the engine is started, the lock-up operating pressure P _{LU is} substantially zero in response to the lock-up inactive state.
At this time, the clutch operating pressure _PCL becomes substantially zero, so that the piston 133 does not make a stroke and enters the stationary state shown in FIG. In this stationary state, the drive plate 139 and the driven plate 140
The frictional contact between the multiple disc clutch 130 is brought into the engaged state (the state where the engine and the torque converter are directly connected), and a large hysteresis torque is generated.

[0026] Thus, by configuring the multiple disc clutch 130 so as to be engaged at rest is not supplied to the clutch working pressure P _CL, so that certainly large hysteresis torque can be obtained at very low rotation region of the engine speed become. Therefore, the clutch having the configuration as in the first embodiment, which is brought into the engaged state when the converter supply pressure Pc is supplied, may not be able to obtain a large hysteresis torque from the beginning depending on the rising characteristic of the hydraulic pressure at the time of engine start. Then, the effect of improving the durability of the torsional damper particularly when the engine is stopped or started is remarkable.

In the engine speed range where the engine speed exceeds the resonance speed of the torsional damper, that is, in the lock-up operation range, as shown in FIG. 12, the supply amount of the clutch operating pressure _PCL increases. As a result, the piston 133 strokes against the spring force of the disc spring 142, and the drive plate 139 and the driven plate 140
The separated state of the multiple disc clutch 130 is released, and the generated hysteresis torque becomes extremely small (substantially zero). Thereby, the same excellent vibration reduction effect as in the first reference example can be obtained.

FIG. 13 is a longitudinal sectional view showing the structure of a third embodiment of the torsion damper of the present invention. In this third embodiment, a portion of a torsional damper and a portion of an adjacent torque converter with a lock-up mechanism are configured as shown in FIG. 13, and a multi-plate clutch (clutch means) 150 for generating hysteresis torque is provided between the two. Is provided. Although the structures of the torsion damper and the torque converter are slightly different from those of the first embodiment, their functions are almost the same as those of the first embodiment.

The torsional damper of the third embodiment is
A hub portion 152a of a hub case 152 as a driving member composed of two plates is directly connected to a crankshaft 151 of the engine by a bolt 153, and a hub arm 154 as a driven member is sandwiched between the two plates of the hub case 152. 152 to the converter cover 157 of the torque converter with lock-up 156 with bolts 155, and a torsion spring is installed in the hub case 152 and the hub arm 154.
The ring gear 159 is fixed to the outer periphery of the outer peripheral annular portion 152b of the hub case 152 by inserting the ring gear 159 therebetween.

As shown in FIG. 13, the multi-plate clutch 150 includes a clutch hub 160 formed integrally with a hub 152a directly connected to the crankshaft 151, and a converter cover 15 as shown in FIG.
7, a piston 162 slidably fitted between the converter cover 157 and the clutch case 161, an oil seal 164 for storing the clutch operating pressure in an oil chamber 163 inside the clutch, 165
And a snap ring 166 for fixing each plate of the multi-plate clutch 150 described later to the clutch case 161. Further, as shown in FIG. 14 which is a detailed view of the clutch portion in FIG. 13, the multi-plate clutch 150 has a drive plate 167 which is spline-engaged with the clutch hub 160, and a drive plate 16 which is spline-engaged with the clutch case 161.
7 comprises a driven plate 168 and a retaining plate 169 which are in frictional contact alternately. Oil chamber 16
3 is an oil passage 157a provided in the converter cover 157, and the converter cover 157 and the lock-up piston
The lock-up control pressure P _{L / C in} the lock-up control chamber, which is communicated with the lock-up control chamber 171 formed between the oil passages, is the clutch operating pressure _PCL .

The hydraulic circuit for supplying the clutch actuating pressure P _CL to the oil chamber 163 is used as the same as the first reference example of FIG. 6, by a computer 122b the exciting current to the pressure control solenoid 122a in its hydraulic circuit The clutch operating pressure _PCL is variably controlled by the adjustment. In this hydraulic circuit, the computer 122b controls the hysteresis torque (friction torque) generated by the clutch 150 according to the present embodiment in accordance with the engine speed and the lock-up operation state of the torque converter as in the first embodiment. Perform control.

In the hysteresis torque control, when the lock-up is not operated, a hydraulic control for increasing the lock-up control pressure P _{L / C} of the lock-up control chamber 171 and making the converter supply pressure Pc of the torque converter 156 almost zero is performed. From the clutch operating pressure P _CL via the oil passage 157a.
The hydraulic pressure in the oil chamber 163 of the clutch 150 supplied with the hydraulic pressure rises and the piston 162 strokes, and the drive plate 167
And the driven plates 168 are fastened to generate a large hysteresis torque corresponding to the oil pressure in the oil chamber 163. On the other hand, during the lock-up operation, the lock-up control pressure P
Piston 162 to lower the oil pressure P _CL of the oil chamber 163 becomes _{L / C} is almost zero without stroke, the stationary state shown in FIG. 14. In this stationary state, the drive plate 167 and the driven plate 168 are separated from each other, and the clutch 150 is released, so that the generated hysteresis torque is extremely small.

By this hysteresis torque control, FIG.
5 (b) suppresses excessive torque fluctuations when passing through the torsional damper resonance speed indicated by the solid line, and prevents a decrease in the vibration reduction effect in a practical range where the engine speed indicated by the dotted line exceeds the resonance speed. (A) of FIG. 2A, which achieves both resonance characteristics in a low engine speed region and vibration reduction characteristics in a practical engine speed region.
As a result, the desired characteristics as shown in the following are obtained, and the engine speed (vehicle speed) during the lock-up operation is reduced, thereby improving the fuel efficiency.

FIG. 16 is a longitudinal sectional view showing the structure of a torsion damper according to a second embodiment of the present invention. In the second embodiment, a torsion damper and an adjacent torque converter with a lock-up mechanism are configured in the same manner as in the specification of Japanese Patent Application No. 3-115233 previously filed by the present applicant. This is provided with a viscous damping mechanism 180 for generating resistance. In the torsion damper of the second embodiment, the same parts as in Japanese Patent Application No. 3-115233 are disclosed.
The reference numeral in the reference number 115233 is increased by 200, and the changed parts in this example are denoted by reference numerals 180 and thereafter, and the engine crank end 201 is connected to the torque converter 20.
A viscous damping mechanism 180 is disposed at the fitting portion that is drivingly connected to the second unit 2, and a viscous coupling such as a viscous coupling (product name) is used as the viscous damping mechanism 180.

The viscous damping mechanism 180 has a retainer 181 sandwiched between the end face of the engine crank end 201 and the drive plate 206, and rotatably supports the inner hub 182 inside the retainer 181 and inside the engine crank end 201. With the seal ring 183, and the inner hub 18
2 is spline-fitted with the central projection 202a of the torque converter 202 on the inner circumference and a plurality of inner plates 18 on the outer circumference.
4 are spline-fitted, the outer plates 185 are arranged between the inner plates 184, and the outer plate 185 is spline-fitted to the inner periphery of the engine crank end 201 facing the inner hub 182, and the space between the outer plates 185 is elastic. A spacer ring 186 made of a member (for example, heat-resistant rubber) is used to keep the space constant, and a sealed space containing the inner plate 184 and the outer plate 185 is filled with a highly viscous substance (eg, grease or silicone oil) as a viscous fluid. The configuration is the same as that of JP-A-3-115233. The viscous damping mechanism 180 functions as a rotational vibration damping element in which a highly viscous substance gives resistance to relative rotation between the engine crank end 201 and the torque converter 202 to attenuate rotational vibration.

In this embodiment, a shape-changing member (a member made of a material having a large coefficient of thermal expansion such as lead or special resin) 187 is provided between the retainer 181 and the outer plate 185 in contrast to the configuration of Japanese Patent Application No. 3-115233. We have made some changes. This change is a countermeasure against occurrence of the same problem as the above-described conventional example due to the damping characteristic of the viscous damping mechanism being affected by the temperature change of the high-viscosity material. It is caused by an environmental temperature change or heat generated when the relative displacement of the torsional damper becomes large when passing through the resonance point.

Next, the operation of the second embodiment will be described. First,
When the high-viscosity material filled in the closed space of the viscous damping mechanism 180 is at a low temperature, the axial dimension (and thus the volume) of the shape changing member 187 is reduced as shown in FIG. The clearance h between the inner plate 184 and the outer plate 185 determined by the member 187 increases. At this time, since the viscosity coefficient μ of the highly viscous substance is large due to the low temperature, 1 / h
Is the small value of 1 / h
And a large value of μ, and the damping characteristic of the viscous damping mechanism 180 is as shown by the dotted line in FIG.

On the other hand, when the high-viscosity material is at a high temperature, the axial dimension (therefore, the volume) of the shape changing member 187 is reduced as shown in FIG.
As shown in (b), the spacer ring 186
And the clearance h between the inner plate 184 and the outer plate 185 determined by the shape changing member 187.
Becomes smaller. At this time, since the viscosity coefficient μ of the highly viscous substance is small due to the high temperature, the viscous damping rate expressed by the product of 1 / h and μ is the product of 1 / h of the large value and μ of the small value. The damping characteristics of the viscous damping mechanism 180 are shown in FIG.
(A) is as shown by the solid line.

As a result, the excessive torque fluctuation when passing through the torsional damper resonance speed shown by the solid line in FIG. 18B is suppressed, and the vibration reduction in the practical range where the engine speed exceeds the resonance speed shown by the dotted line. It is possible to prevent the reduction of the effect, and to achieve both the resonance characteristics in the low engine speed region at high temperature and the vibration reduction characteristics in the practical range of the engine speed at low temperature, as shown in FIG. Characteristics, and thus, stable damping characteristics independent of the temperature of the highly viscous substance are obtained.

In the second embodiment, the shape changing member 187 made of a material having a large coefficient of thermal expansion is used as the shape changing member. Instead, as shown in FIGS. A spring 188 made of a shape memory alloy whose shape changes according to the temperature may be used. In this case, the spring 188 contracts as shown in FIG. Since 188 is elongated, the same operation and effect as in the second embodiment can be obtained.

Further, in the second embodiment, the viscous damping mechanism is used.
A viscous coupling such as a viscous coupling (trade name) is used as 180. Instead, Daikin Technical Report 39, 1990, October issue, pages 14 to 15, described in Daikin Manufacturing Co., Ltd. A viscous damping mechanism using a viscous fluid passing through the throttle may be used.In this case, a member made of a material having a large thermal expansion coefficient or a shape memory alloy that changes its shape depending on the temperature is used for a portion forming the throttle. The same operation and effect as those of the fifth embodiment can be obtained.

[0042]

As described above, the torsion damper according to the present invention is constructed so that both the improvement of the durability of the torsion damper at the time of starting the engine and the effect of reducing the vibration in the engine speed range can be achieved. From claim 1
In the configuration of (1), when the engine is started, the starter motor pinion meshes synchronously with a ring gear fixed to a driving member coupled to the engine output shaft and a synchronous meshing means provided on a driven member coupled to the torque converter, During that time, the engine speed exceeds the resonance speed of the torsional damper, so that the excessive torque fluctuation phenomenon at the time of passing the resonance point as in the conventional example described above does not occur, and the durability of the torsional damper is improved.

After releasing the above-mentioned synchronous meshing state,
The function as a damping element is almost eliminated in a practical engine speed range, and a good vibration reduction effect at the time of lock-up operation can be obtained.

According to the third aspect of the present invention, the shape changing member, which changes its shape in accordance with the temperature of the viscous fluid, changes the damping characteristic of the rotary vibration damping element which gives resistance to the relative rotation between the engine crank end and the torque converter. It is possible to realize a stable damping characteristic which is not affected by a temperature change by making the fluid at a low temperature and a high temperature substantially the same, and suppresses the level of the torque fluctuation at the time of passing the resonance point at a low temperature of the viscous fluid to torsional. In addition to improving the durability of the damper, at the time of high temperature of the viscous fluid, there is almost no effect as a damping element in a practical engine speed range, and a good vibration reduction effect at the time of lock-up operation is exhibited.

[Brief description of the drawings]

FIG. 1 is a longitudinal sectional view showing a configuration of a first embodiment of a torsional damper of the present invention.

FIG. 2 is a diagram viewed from the arrow A in FIG. 1;

FIG. 3 is a diagram viewed from an arrow B in FIG. 1;

FIGS. 4A, 4B, and 4C are diagrams for explaining the operation of the torsional damper of the same example.

FIG. 5 is a longitudinal sectional view showing a configuration of a first reference example of the torsional damper of the present invention.

FIG. 6 is a circuit diagram of a hydraulic circuit used in the same example.

FIG. 7 is a diagram showing control characteristics of a converter operating pressure of the same example.

FIG. 8 is a diagram showing a hysteresis torque in a torsional characteristic of the torsion damper of the same example.

FIG. 9 is a longitudinal sectional view showing a configuration of a second reference example of the torsional damper of the present invention.

FIG. 10 is a detailed view of a clutch unit shown in FIG. 9;

FIG. 11 is an exploded perspective view of the clutch unit of the same example.

FIG. 12 is a diagram showing a state when the clutch of the same example is operated.

FIG. 13 is a longitudinal sectional view showing a configuration of a third reference example of the torsional damper of the present invention.

14 is a detailed view of a clutch unit shown in FIG.

FIGS. 15A and 15B are diagrams for explaining the operation of the torsional damper of the same example.

FIG. 16 is a longitudinal sectional view showing the configuration of a second embodiment of the torsion damper of the present invention.

FIGS. 17 (a) and (b) are diagrams showing a state at a low temperature and a state at a high temperature, respectively, when a member made of a material having a large thermal expansion coefficient is used as the shape changing member of the same example.

FIGS. 18A and 18B are views for explaining the operation of the torsional damper of the same example.

FIGS. 19 (a) and (b) are diagrams showing a state at a low temperature and a state at a high temperature, respectively, when a spring made of a shape memory alloy is used as the shape changing member of the same example.

FIG. 20 is a longitudinal sectional view showing a configuration of a conventional torsional damper.

FIG. 21 is a diagram showing torque fluctuation of a drive shaft according to whether or not a damping element is added in a conventional example.

FIGS. 22 (a), (b), and (c) are diagrams for explaining the operation of a conventional torsional damper.

[Explanation of symbols]

 Reference Signs List 1 crankshaft (output shaft) 2 converter cover 11 hub arm (drive member) 11a hub 13 ring gear 15 torsion spring 16 hub case (non-drive member) 20 ring gear (synchronous meshing means) 21 clutch (clutch means) 21a cone cracke 21b clutch facing 22 Working surface 114 Converter room 122 Pressure reducing valve 122b Computer 130 Multi-plate clutch (clutch means) 142 Disc spring 150 Multi-plate clutch (clutch means) 180 Viscous damping mechanism (rotational vibration damping element) 187 Shape changing member (material with large thermal expansion coefficient) 188 Shape changing member (Spring made of shape memory alloy) 201 Engine crank end 202 Torque converter

Continuing on the front page (72) Inventor Shoichi Tsuchiya 1370 Onna, Atsugi-shi, Kanagawa Prefecture Inside Atsugi Unisia Co., Ltd. 56) References JP-A-58-214057 (JP, A) JP-A-61-278625 (JP, A) JP-A-62-9303 (JP, A) Full-open sho-59-171250 (JP, U) 63-196830 (JP, U) (58) Fields investigated (Int. Cl. ⁷ , DB name) F16F 15/134 F02N 15/02 F16H 41/24 F16F 15/16 F16D 35/00 F16F 15/129 F16F 15/139

Claims (3)

(57) [Claims] An engine includes a driving member coupled to an engine output shaft, a ring gear fixed to the driving member, and a driven member coupled to a torque converter, for drivingly coupling between the engine and the torque converter. A torsional damper, wherein a synchronous meshing means for meshing with a starter motor pinion in synchronization with the ring gear when a starter motor is operated is provided on the driven member. 2. The torsional damper according to claim 1, wherein said synchronous meshing means is a ring gear having teeth which are tapered in a starter motor pinion approach direction. 3. A part of a torque converter, which is drivingly coupled to an engine crank end via a torsional damper, is fitted into the engine crank end so as to be relatively rotatable, and imparts resistance to the fitted portion to the relative rotation. In a torsional damper in which a rotational vibration damping element is arranged, a shape changing member that changes its shape according to the temperature of the viscous fluid so that the damping characteristic of the rotational vibration damping element is substantially the same at low and high temperatures of the viscous fluid. Characterized in that it is provided,
Torsional damper.