JPH03144152A - Torque converter - Google Patents

Abstract

PURPOSE:To increase capacity, improve response, and reduce the shock in speed change, by setting the inner edges of the blades of a pump vane wheel and a turbine vane wheel to the outer peripheral position of a stator vane wheel and fixedly installing a core member for connecting the outer peripheral edge of a stator blade. CONSTITUTION:The inner edges of the blades 3b and 5b of a pump vane wheel 3 and a turbine vane wheel 5 are set close to the outer peripheral position of a stator vane wheel 8, and a pump core and turbine core are omitted. A core member 10 is fixedly installed by connecting the outer peripheral edge of the stator blade 8b of the stator vane wheel 8, and smooth circular outer peripheral surfaces 101 and 102 are formed on the core member 10, and circular cut surfaces 31 and 51 are formed on the inner edges of the blades 3b and 5b of the pump vane wheel 3 and the turbine vane wheel 5. Accordingly, the torque capacity is increased, and the response in acceleration is improved, and the speed change shock can be reduced.

Description

DETAILED DESCRIPTION OF THE INVENTION (Field of Industrial Application) The present invention relates to a three-element, two-phase torque converter that is applied to automatic transmissions and the like.

(Prior art) Conventionally, as a coreless torque converter, for example, S
A E (Society of Automotive
e Engineers) Technical Paper Series 8
61213, etc., and in this conventional source, the pump core, turbine core, and stator core are omitted by making the inner ends of each blade of the pump impeller, turbine impeller, and stator impeller close to each other. death,
A torque converter is shown with the flow path expanded to the center of the three elements.

In addition, as a general type torque converter, for example, the one described in Figure 3.105 on page 203 of "Automotive Engineering Complete Book Volume 9 Power Transmission Device" (November 1980; published by Sankaido) is known. This conventional source discloses a torque converter in which a turbine core and a stator core are installed at the inner ends of each blade of a pump impeller, a turbine impeller, and a stator impeller, respectively.

(Problem to be Solved by the Invention) However, in the former coreless torque converter, most of the flow path acts as a torque converter, but the stator does not work in the area around the outer periphery of the stator in the center of the flow path, so-called Acts as a fluid coupling.

Therefore, in terms of overall torque converter performance, although the coreless structure has the advantage of a very large torque capacity due to the enlarged flow path, the stall torque ratio (the torque ratio when the pump is rotating and the turbine is stopped, and the stall torque ) is not large enough. As a result, it is difficult to apply it to a small displacement type with a large weight ratio that requires a high stall torque ratio.

In addition, the latter type of general torque converter not only has a small torque capacity due to the narrow flow path due to the core structure, but also has a high weight because a pump core and a turbine core are installed in the pump impeller and turbine impeller. As a result, the rotational inertia of the rotating pump impeller and turbine impeller is large, resulting in poor response during acceleration and large shock during gear changes.

The present invention has been made with attention to the above-mentioned problems, and in a three-element two-phase torque converter, the stall torque ratio is improved compared to a coreless torque converter, and the torque is reduced compared to a general type torque converter. The first objective is to increase capacity, improve response during acceleration, and reduce shock during gear shifts.

In addition to the first objective, the second objective is to obtain a torque capacity almost equivalent to that of a coreless torque converter, and to improve the blade rigidity and blade durability reliability of the pump impeller and the turbine impeller.

(Means for Solving the Problem) In order to solve the first problem, in the torque converter according to the first aspect, a core member is fixedly installed only on the stator impeller among the three elements.

That is, it includes a pump impeller connected to the input shaft, a turbine impeller connected to the output shaft, and a stator impeller fixed to the case via a one-way clutch, and the inside is filled with working fluid. In a torque converter, the inner ends of the blades of the front pump impeller and the turbine impeller are brought close to the outer periphery of the stator impeller, thereby omitting the pump core and turbine core, and the outer periphery of each stator blade is placed only in the stator impeller. It is characterized by a fixed core member that connects the two.

In order to solve the second problem, in the torque converter according to the second aspect, the area occupied by the core member is limited to a substantially semicircular cross-sectional area that acts as a fluid coupling in the coreless torque converter.

That is, in the torque converter according to claim 1, the core member has a smooth circular arc outer circumferential surface along the streamline, and each blade inner end of the pump impeller and the turbine impeller has a circular arc notch surface along the circular arc outer circumferential surface. It is characterized by being formed.

(for production) The invention according to claim 1 will be explained in detail.

When the input shaft is driven to rotate and a flow of working fluid circulates through the pump impeller, turbine impeller, and stator impeller, in the converter range where the torque ratio is less than 1, the turbine impeller receives fluid and flows to the output shaft. The transmitted torque exhibits a so-called torque increasing effect, in which the stationary stator impeller increases by the stator torque received from the fluid.

Therefore, in the case of a coreless torque converter, the flow that flows from the stator blade outlet of the stator impeller to the pump blade inlet of the pump impeller exhibits a torque increasing effect, but the flow from the outer peripheral end of the stator blade to the inner end of the pump blade Since the short-circuit inflow flow hardly passes through the stator impeller and the pump impeller, it does not exhibit a torque increasing effect, and a so-called fluid coupling region is formed in the outer peripheral portion of the stator.

However, in the case of the present invention, since the core member that connects the outer peripheral end of each stator blade is fixedly installed only on the stator impeller, fluid leakage from the outer peripheral end of the stator blade is prevented, and the stator impeller Most of the working fluid flows from the stator blade outlet into the pump blade inlet of the pump impeller, and the working fluid passes through the stator blade and pump blade without waste, exhibiting a torque increasing effect, compared to a coreless torque converter. In some cases, the stall torque ratio can be improved.

Furthermore, since the pump core and turbine core of the pump impeller and turbine impeller are omitted, when compared with a general torque converter, the torque capacity can be increased by expanding the flow path due to the omission of the core.

Furthermore, the weight of the pump impeller and the turbine impeller are reduced by omitting the core, and rotation and clarity are reduced, so it is possible to improve response during acceleration and reduce shock during gear changes. Note that since the stator impeller to which the core member is fixed is stationary within the converter range, no rotational characteristic occurs.

The invention according to claim 2 will be explained in detail.

In the above-mentioned torque increasing effect, since the core member has a smooth arcuate outer circumferential surface that follows the streamline, collision loss between the circulating fluid and the core member is minimized, and the flow is increased along the arcuate outer circumferential surface of the core member. The speed is increased and the circulating flow rate is almost the same as that of a coreless torque converter with the same diameter.

In other words, it is possible to obtain approximately the same torque capacity as a coreless torque converter.

In addition, since the inner ends of the blades of the pump impeller and turbine impeller are formed into circular notches along the outer peripheral surface of this arc, the height of each breech of the pump impeller and turbine impeller is lower than that of a coreless torque converter. is lower, blade rigidity is improved, and it is resistant to vibration.

Furthermore, in coreless torque converters, corners are formed on each blade of the pump impeller and turbine impeller by placing them close to the stator blades, but these corners are eliminated, preventing the occurrence of cracks, etc., and increasing the blade durability. Reliability is also improved.

(Example) Embodiments of the present invention will be described below based on the drawings.

First, the configuration will be explained.

FIG. 1 is a 3
It is a one-stage, two-phase type torque converter, and is connected to a pump impeller 3 that is connected to an engine crankshaft 1 that is an input shaft via a converter cover 2, and to a transmission input shaft 4 that is an output shaft. It includes a turbine impeller 5 and a stator impeller 8 fixed to a transmission case 7 via a one-way clutch 6, and an internal chamber surrounded by an integrated pump shell 3a and converter cover 2 is filled with hydraulic oil. .

The pump impeller 3 includes a pump shell 3a serving as an outer shell, and a large number of pump blades 3b provided inside the pump shell 3a.

The turbine impeller 5 has a turbine shell 5 serving as an outer shell.
a, and a large number of turbine blades 5b provided inside the turbine shell 5a.

The inner ends of the blades of the pump impeller 3 and the turbine impeller 5 are brought close to the outer peripheral position of the stator impeller 8, thereby omitting the pump core and the turbine core.

The stator impeller 8 has a stator shell 8 serving as an outer shell.
a, and a large number of stator blades 8b provided inside the stator shell 8a.

A core member 10 is fixedly installed only on the stator impeller 8 by connecting the outer circumferential ends of each stator blade 8b. The inner ends of the blades of the pump impeller 3 and the turbine impeller 5 are formed into circular cutout surfaces 31 and 51 along the circular arc outer peripheral surfaces 101 and 102, respectively.

The core member 10 is fixed to the stator blade 8b by wrapping a band-shaped member formed from a rolled steel plate by a method such as pressing around the outer peripheral end of the stator blade 8b and line welding a part of the periphery. The stator core part has a stator core part 10a in contact with the outer circumferential end of the blade 8b, a pump core part 10b along the circular arc notch surface 31 of the pump impeller 3, and a turbine core part 10c along the circular arc notch surface 51 of the turbine impeller 5. The core member 10 is positioned in the axial direction by the uneven engagement between the positioning recess 10d formed on the stator blade 10a and the positioning protrusion 8c formed on the stator blade 8b. Note that the relationship between the unevenness for positioning may be reversed.

In FIG. 1, 11 is a pump hub, 12 is a turbine hub, and 13 and 14 are thrust bearings.

Next, the effect will be explained.

(a) Torque increase effect The engine crankshaft 1 rotates due to the engine drive, and rotational driving force is input to the pump impeller 3, and as shown by the arrow in FIG. 1, the pump impeller 3 and the turbine impeller 5
When a flow of hydraulic oil circulates through the stator impeller 8, in the converter range where the torque ratio is 1 or less, the torque received by the turbine impeller 8 from the hydraulic oil and transmitted to the transmission input shaft 4 is stationary. The stator impeller 8 increases by the stator torque received from the hydraulic oil, which is a so-called torque increasing effect.

Therefore, in the case of the coreless torque converter shown in Fig. 2, the flow rate Q8 flowing from the stator blade outlet of the stator impeller to the pump blade inlet of the pump impeller
indicates a torque increasing effect, or the flow rate OA flowing in a short circuit from the outer peripheral end of the stator blade to the inner end of the pump blade.
Since it hardly passes through the stator impeller and pump impeller, it does not exhibit a torque increasing effect, and a so-called fluid coupling region is formed in the outer peripheral portion of the stator.

However, in the case of the embodiment, a core member 10 connecting the outer peripheral end of each stator blade 8b only to the stator impeller 8
is fixedly installed, as shown in Fig. 3, leakage of hydraulic oil from the outer peripheral edge of the stator blade 8b is prevented, and most of the hydraulic oil flows from the stator blade outlet of the stator impeller 8 to the pump impeller. stator blade 8b and pump blade 3b.
This means that the hydraulic oil passes through without wastage and exhibits a torque increasing effect.

In other words, when compared to a coreless torque converter,
The torque ratio will increase by at least (OA+QB)/Q[1, and the stall torque ratio (pump impeller 3
The rotation of the turbine impeller 5 can improve the ratio of the turbine torque to the pump torque when the turbine impeller 5 is stopped.

In the case of the torque converter of the embodiment, the pump core and turbine core of the pump impeller 3 and the turbine impeller 5 are omitted, so when compared with a general type torque converter,
Of course, the torque capacity can be increased by expanding the flow path by omitting the core.

Furthermore, since the core member 10 has smooth circular arc outer peripheral surfaces 101 and 102 that follow the streamlines of the circulating hydraulic oil, collision loss between the circulating differential oil and the core member 10 is minimized, and the core member 10 The flow speed is increased along the arcuate outer circumferential surfaces 101 and 102, and a circulating flow rate approximately equivalent to that of a coreless torque converter with the same diameter is obtained.

In other words, it is possible to obtain approximately the same torque capacity as a coreless torque converter.

(c) Torque converter operation during driving In the case of the torque converter in the example, the pump impeller 3
And the weight of the turbine impeller 5 is reduced by omitting the core.

In other words, when compared to a general torque converter in which the pump impeller and the turbine impeller have cores, the rotational inertia is reduced due to the weight reduction. In addition, core member 1
Since the stator impeller 8, which is fixed at 0, is stationary in the converter region, no rotational inertia occurs.

Therefore, during acceleration, when the engine speed is increased by pressing the accelerator, the turbine impeller 5 rotates in response to the increase in the rotation of the pump blade type 3, improving the response during acceleration. can.

Furthermore, during gear shifting, the difference in rotational speed before and after the gear shifting is reduced due to the good rotation followability of the input/output shafts 1 and 4, and it is possible to reduce gear shifting shock.

As explained above, in the torque converter of the first embodiment, the effects listed below can be obtained.

(2) By installing the core member 10, the torque ratio can be increased compared to a coreless 1-lux converter.

As a result, it can be applied to small displacement models with a large weight power ratio that require a high stall torque ratio.

(2) Since the area occupied by the core member 10 is limited to the approximately semicircular cross-sectional area that acts as a fluid coupling in the coreless torque converter, it is possible to obtain a high torque capacity almost equivalent to that of a coreless torque converter with the same diameter.

As a result, the torque converter can be made more compact, which is very advantageous in terms of vehicle layout.

■ The core member 10 is installed only on the stator impeller 8 that is stationary in the converter range, and the cores of the pump impeller 3 and turbine impeller 5 are omitted. Rotational inertia can be reduced.

As a result, the response during acceleration is improved, resulting in better acceleration performance, and the shock reduction during shifting improves shift quality.

■ The inner ends of the blades of the pump impeller 3 and the turbine impeller 5 are formed into circular cutout surfaces 31.51 along the circular arc outer circumferential surfaces 101° and 102 of the core member 10, so the difference between FIGS. 2 and 3 is As is clear from the comparison, the pump impeller 3 and turbine impeller 5 are smaller than the coreless torque converter.
The height of each blade 3b, 5b is reduced, and blade rigidity is improved.

As a result, the natural frequency becomes high, making it resistant to vibration.

■ As shown in Figure 2, in a coreless torque converter, corner portions are formed on each blade of the pump impeller and turbine impeller by placing them close to the stator blade, but in the torque converter of the embodiment, circular notches are formed on each blade of the pump impeller and turbine impeller. Surface 31. ．．
51 eliminates this corner portion and prevents the occurrence of cracks and the like.

As a result, the blade durability and reliability are improved, and the life of the torque converter is also extended.

■ Since the pump impeller 3 and turbine impeller 5 have a structure in which the core is omitted, these impellers 3.5 can of course be manufactured with a sheet metal welded structure, and can also be manufactured using aluminum die-casting, which is highly advantageous in terms of manufacturing man-hours. But it can be manufactured.

Although the embodiments have been described above based on the drawings, the specific configuration is not limited to these embodiments, and any design changes or the like that do not depart from the gist of the present invention are included in the present invention.

For example, the shape of the core member is not necessarily limited to the shape of the embodiment.

(Effects of the Invention) As explained above, in the three-element two-phase torque converter according to claim 1, since the core member is fixedly installed only on the stator impeller among the three elements, the coreless torque converter It is possible to increase the torque capacity compared to a general type torque converter while improving the stall torque ratio compared to the conventional torque converter, and also to improve the response during acceleration and reduce shock during shifting.

Further, in the three-element two-phase torque converter according to claim 2, the core member is fixedly installed only on the stator impeller, and the area occupied by the core member acts as a fluid coupling in the coreless torque converter. Since it is limited to a substantially semicircular cross-sectional area, in addition to the above effects, it is possible to obtain a torque capacity almost equivalent to that of a coreless torque converter, and to improve the blade rigidity and blade durability reliability of the pump impeller and turbine impeller. The effect is that it can be done.

[Brief explanation of the drawing]

Fig. 1 is a sectional view showing a torque converter according to an embodiment of the present invention, Fig. 2 is a diagram illustrating the torque increasing effect in a conventional coreless torque converter, and Fig. 3 is a diagram illustrating the torque increasing effect in the torque converter according to the embodiment. be. 1... Engine crankshaft (input shaft) 2... Converter cover 3... Pump impeller 3b... Pump blade 31... Arc notch surface 4... Transmission input shaft (output shaft) 5...Turbine impeller 5b...Turbine blade 51...Circular cutout surface 6...One-way clutch 7...Transmission case (case) 8...Stator impeller 8b...Stator blade 10. ... Core member 101.102 ... Arc outer peripheral surface

Claims (1)

[Claims] 1) A pump impeller connected to an input shaft, a turbine impeller connected to an output shaft, and a stator impeller fixed to a case via a one-way clutch; In a torque converter filled with working fluid, the inner ends of the blades of the pump impeller and the turbine impeller are brought close to the outer periphery of the stator impeller, the pump core and the turbine core are omitted, and only the stator impeller is provided with individual blades. A torque converter characterized in that a core member that connects the outer peripheral ends of stator blades is fixedly installed. 2) In the torque converter according to claim 1, the core member has a smooth circular arc outer circumferential surface along the streamline, and each blade inner end of the pump impeller and the turbine impeller has a circular arc notch surface along the circular arc outer circumferential surface. A torque converter characterized by being formed.