JP4115190B2 - Fluid impeller - Google Patents

Description

[0001]
BACKGROUND OF THE INVENTION
The present invention relates to a fluid impeller used in a torque converter or the like, and more particularly to a fluid impeller having an improved brazing structure for brazing a blade to a shell.
[0002]
[Prior art]
Conventionally, as a fluid impeller such as a pump impeller of a torque converter or a turbine runner, for example, one disclosed in JP-A-58-97448 is known.
[0003]
This is a fluid impeller using single blades separated one by one. Conventionally, in this kind of single blade type fluid impeller, the projection of the blade is fitted into the slit of the core, and the slit is inserted into the slit. The blade and core are welded with brazing material from the mated protrusions to prepare a core / blade assembly in advance, and then placed on the shell in a state where it is placed horizontally, and the blade and core are placed against the shell. After positioning the outer end and the inner end, a brazing filler metal was placed near the outer end of the blade, and the blade and the shell were brazed and fixed by passing through a furnace in a predetermined atmosphere. The positioning of the outer edge of the blade with respect to the shell is performed by, for example, fitting of irregularities, and the positioning of the inner edge of the blade is performed by fitting of irregularities and / or pressing by a retainer.
[0004]
However, in the above-described single blade type, in order to create a core / blade assembly, it is necessary to weld with a brazing material with the projections of the blade fitted in the core in advance, which requires labor and accuracy in the assembly work. There was a problem.
[0005]
Therefore, the present applicant has recently proposed a fluid impeller disclosed in Japanese Patent Application Laid-Open No. 2001-141028. This uses a connection-type blade whose outer end edges are connected to each other by an annular connecting portion. In this blade connection type, there is no need to pre-assemble the core and blade, so the blade outer end and inner end are positioned directly with respect to the shell in the horizontal position, and the blade is placed directly on the shell. Then, in the same manner as described above, the protrusion is fitted into the slit and the core is placed on the blade, and then a brazing filler material in the form of a wire is placed at a position near the protrusion and the outer end of the blade, and the inside of the furnace is placed. By passing, the blade and the core, and the blade and the shell are brazed and fixed.
[0006]
[Problems to be solved by the invention]
In this blade connection type, it is not necessary to perform the work of welding with the brazing material in advance aiming at the projection of the blade fitted to the core, but it is difficult to position the brazing material so as to contact all the projections. For this reason, the melted brazing material accumulates in places other than the slits on the core, and the brazing material cannot be spread from the slit to the entire contact portion between the blade and the core using the capillary phenomenon. There was a problem that a non-joined portion remained between the blades and a blade with insufficient joint strength with the core was generated.
[0007]
Such a problem is that the single type blade is placed directly on the shell, without separating the single type blades separated one by one on the shell, and the brazing material in the form of wiring makes the blade, shell, blade and its The same occurs when brazing the upper core.
[0008]
Therefore, an object of the present invention is to braze and fix a blade and a core in which the projection of the blade is fitted into the slit without causing a non-joined portion, and to obtain a fluid impeller having sufficient joint strength between the blade and the core. Is to provide.
[0009]
[Means for Solving the Problems]
In order to solve the above-mentioned problems, the present invention positions a plurality of blades arranged radially with respect to the shell, engages the projections on the inner edge of the blades with the slits of the core, and puts the blades in a horizontal state. In the fluid impeller in which the inner edge of the blade and the core and the outer edge of the blade and the shell are brazed by placing a wire-like brazing filler metal at the position of the protrusion and the position near the outer end and heating,
Inner edge of the projection is provided so as to protrude from a portion of the core, further has a substantially upright in a substantially state where a same thickness and transversely to the blade and the blade, the further protrusion of the tip With a recess ,
Fluid impeller for a brazing material of positions of the projections fitted into the slits of the core is characterized in that is held in the recess.
[0010]
According to the invention, the recess has a depth to hold the brazing material. Preferably, the concave portion is formed in a groove having a substantially parallel straight portion. A retainer may be provided for positioning the inner end of the blade relative to the shell. Further, the blade may be a connection type blade in which outer edges of the blades are connected by an annular connecting portion, and preferably a gap is provided without contacting the connecting portion and the shell.
[0011]
In the present invention, since the brazing filler metal that joins the blade and the core is held in the recesses of the projections of the blades fitted into the slits of the core, the melted brazing material is transmitted through the projections and enters the slits in each blade. The capillarity penetrates the gap between the contact portion between the inner edge of the blade and the core and spreads over the entire surface, and the blade and the core are brazed and fixed satisfactorily without any non-bonded portion in all the blades. Therefore, the fluid impeller can be made to have sufficient joint strength between the blade and the core.
[0012]
When the concave part of the protrusion is formed in a hole having a parallel straight part, the brazing material inserted into the concave part can be held in pressure contact with the straight part from both sides of the cross section, so the removal of the brazing material from the concave part is more effective. Can be prevented. As the blade, in addition to a single type separated one by one, a connection type in which the outer edges of the blades are connected by an annular connection part can be used. In this case, the connection part of the blade is brazed to the shell. However, there is almost no influence on the bonding strength between the blade itself and the shell. Therefore, if the gap is provided without contacting the connecting portion and the shell, the connecting portion can be prevented from being brazed to the shell, and the brazing material can be saved correspondingly.
[0013]
In addition, when a retainer that positions the inner end of the blade with respect to the shell is provided, a gap is formed between the retainer and the inner end of the blade in the circumferential direction of the retainer. Even if there is a break in the middle of the contact area, the brazing material enters the retainer circumferential gap at the point where the molten brazing material is transmitted to the inner edge of the blade, and then the brazing material is cut off from the middle of the blade. It can penetrate into the gap between the contact portion between the outer edge and the shell. Therefore, it is possible to more reliably obtain a good brazing without any non-bonded portion between the blades and the shell.
[0014]
DETAILED DESCRIPTION OF THE INVENTION
Hereinafter, embodiments of the present invention will be described in detail.
[0015]
FIG. 1 is a plan view showing an embodiment of a fluid impeller of the present invention.
[0016]
As shown in FIG. 1, in the present embodiment, the fluid impeller is formed in a pump impeller (hereinafter referred to as a pump for short) of a torque converter. The pump 20 includes a shell 2, a large number of, for example, 15 to 30 radially arranged with respect to the shell 2, 23 blades 3 in this example, and a core 4 placed on the blade 3. A retainer 5 that presses the lower end of the blade 3 is provided, and the shell 2 and each blade 3 and between each blade 3 and the core 4 are fixed by brazing. The blade 3 has a loosely twisted surface shape.
[0017]
As shown in FIG. 2, tongue pieces 6 and 7 projecting outward are integrally provided at the outer end 3 c and the inner end 3 d of each blade 3, respectively, Concave portions 8 and 9 corresponding to the tongue pieces 6 and 7 of the blade 3 are provided at the inner surface position near the portion. In addition, a projection 11 is provided at a substantially central portion on the inner edge 3a between the outer and inner straight portions 3e and 3f following the outer end 3c and the inner end 3d of each blade 3, and the core 4 is provided with the projection 11 on the core 4. A corresponding slit 10 is provided.
[0018]
A major feature of the present invention is that the recesses 12 are provided in the protrusions 11 of the blade 3, and the blade 3 and the core 4 are brazed using the brazing material held in the recesses 12.
[0019]
The present invention will be further described in accordance with the method of assembling the pump 20. First, as shown in FIG. 3, the shell 2 is set on the setting jig 16 in a horizontal state, and the blades 3 are radially arranged on the shell 2. The tongue pieces 6 at the outer ends of the blades 3 are inserted into the recesses 8 of the shell 2, and the outer ends 3 c of the blades 3 are positioned with respect to the shell 2. Further, the tongue piece 7 at the inner end of each blade 3 is inserted into the concave portion 9 of the shell, and the tongue piece 7 is further pressed from above by the retainer 5 to position the inner end 3 d of each blade 3 with respect to the shell 2. The retainer 5 is fixed to the shell 2 by spot welding 17 or the like.
[0020]
Next, the core 4 is placed on the inner edge 3 a of the blade 3 disposed on the shell 2, the protrusion 11 of each blade 3 is fitted into the slit 10 of the core 4, and the shell 2 is placed on the set jig 16. A subassembly 15 of the blade 3 and the core 4 is obtained. Then, a brazing filler metal 13 is inserted and held in the recess 12 of the projection 11 of the blade 3 in the subassembly 15, and the brazing filler wire is placed at a position near the outer end 3 c of the linear portion 3 e outside the blade 3. 14 is put.
[0021]
As shown in FIG. 4, the recess 12 of the projection 11 has a depth for holding the brazing material 13, that is, a depth for accommodating substantially the entire cross section of the brazing material 13. The concave portion 12 is formed in a groove having a substantially parallel straight portion 12a. In this way, the brazing material 13 inserted into the recess 12 can be held in pressure contact with the linear portion 12a from both sides of the cross section, so that the detachment of the brazing material 13 from the recess 12 can be more effectively prevented. Depending on the required amount of the brazing material 13, the cross-sectional area is adjusted by making the cross-sectional shape of the brazing material 13 circular or oval, but the width between the substantially parallel straight portions 12 a of the recess 12 is different from that of the brazing material 13. It is specifically determined according to the size of the cross section.
[0022]
When the brazing material 13 is held in the concave portion 12 of the projection 11 of the blade 3 of the subassembly 15 on the setting jig 16 and the brazing material 14 is placed on the straight portion 3e outside the blade 3, as described above. The subassembly 15 together with the jig 16 is placed in a furnace having an inert atmosphere such as nitrogen gas and heated by passing through the furnace. As a result, the brazing material 13 is melted to braze the blade 3 and the core 4, and the brazing material 14 is melted to braze the blade 3 and the shell 2.
[0023]
Since the brazing material 13 for joining the blade 3 and the core 4 is held in the recess 12 provided in the projection 11 of the blade 3 fitted in the slit 10 of the core 4, the brazing material melted by each blade 3 is It passes along the protrusion 11 and enters the slit 10, penetrates into the gap between the contact portion between the inner edge 3 a of the blade 3 and the core 4 by capillary action, and spreads throughout. Therefore, in all the blades 3, the blade 3 and the core 4 are brazed and fixed satisfactorily without causing a non-joined portion.
[0024]
On the other hand, the brazing of the blade 3 and the shell 2 is caused by melting of the brazing material 14 of the straight portion 3e of the blade 3, and the melted brazing material enters the gap between the outer end 3c of the blade 3 and the shell 2 and capillarity occurs. The blade 3 and the shell 2 are brazed together by penetrating into the gap between the outer edge 3a of the blade 3 and the shell 2 and spreading throughout.
[0025]
The brazing between the blade 3 and the shell 2 is normally performed well without any problem. However, depending on the blade 3, sometimes the molten brazing material is interrupted in the middle of the gap between the outer edge 3a of the blade 3 and the shell 2. .
[0026]
On the other hand, as described above, if the retainer 5 is used for positioning the inner end 3d of the blade 3, a gap is generated in the circumferential direction of the retainer 5 between the retainer 5 and the inner end 3d of the blade 3. In the place where the molten brazing material is transmitted to the inner end 3d of the blade 3, the brazing material enters the gap in the circumferential direction of the retainer 5, and the brazing material is contacted between the outer edge 3 b of the blade and the shell 2 which is interrupted in the middle. Can penetrate into the gap. Therefore, it is possible to more reliably obtain a good brazing without any non-joined portion between the blades 3 and the shell 2.
[0027]
According to the present embodiment, as described above, with all the blades, the molten brazing material is spread over the entire contact portion between the blade and the core, and the blade and the core are brazed without causing a non-joined portion. The pump can be fixed, and the joint strength between the blade and the core can be sufficient.
[0028]
An example of a torque converter in which the pump of this embodiment is assembled is shown in FIG.
[0029]
The torque converter (fluid transmission device) 30 includes the pump 20, a turbine runner (abbreviated as a turbine) 33, and a stator 47. The pump 20 is welded to the hub 31 a at the inner edge of the shell 2, and the turbine 33 is welded to the hub 33 a at the inner edge of the shell 34, and is disposed opposite to each other. The hub 33a rotates together with the driven shaft S that is an output shaft. The stator 47 is connected to a fixed shaft via a one-way clutch 47a and a hub 47b.
[0030]
The turbine 33 has substantially the same configuration as that of the pump 20, and the above-described shell 34, blades 35 radially disposed on the shell 34, and the core 35a thereon are integrally assembled by brazing. The outer peripheral end 34 a of the shell 34 is disposed to face the pump 20, and the inner surface of the end 34 a is formed on a surface that substantially coincides with an imaginary line 36 that indicates the outer peripheral surface of the flow flowing from the pump 20. The outer diameter of the end portion 34a is such that a slight gap 37 is formed between the inner surface of the shell 2 on the pump 20 side.
[0031]
In the front cover 38, the hub 38a is loosely fitted to the driven shaft S, and the outer peripheral portion thereof is connected to the shell 2 on the pump 20 side by the welded portion 39 to form a container of the torque converter 30, and the container outer peripheral surface is used for input. A nut 40 and a ring gear 41 for connecting the drive rate are welded.
[0032]
The clutch plate 42 includes a hub 42a, a friction plate 42b, and several spring holding portions 43. A coil spring 44 is inserted into the spring holding portion 43, and both ends of the coil spring 44 are held by retainers 45. The shell 34 of the turbine 33 is provided with a pair of projecting pieces 46 that come into contact with both ends of the coil spring 44 for each spring, and the rotation is transmitted from the projecting pieces 46 to the clutch plate 42 through the coil spring 44. Therefore, when the clutch plate 42 moves right due to the pressure difference and the friction plate 42b contacts the front cover 38, the input applied to the front cover 38 is transmitted to the shell 34 of the turbine 33 via the coil spring 44 and the projecting piece 46, and the hub. 33a is transmitted to the driven shaft (output shaft) S.
[0033]
Another embodiment of the fluid impeller of the present invention is shown in FIG. The present embodiment is characterized in that a connection type blade proposed in Japanese Patent Laid-Open No. 2001-141028 is used as the blade 3 of the pump 20.
[0034]
This connection-type blade 3 is formed by punching a band-shaped metal plate to connect the blades 3 to each other at the outer end 3c through the branch portion 3h by the connection portion 3g, and the blade 3 is twisted. It is raised from the plane including the connecting portion 3g, the branch portion 3h connected to the connecting portion 3g is bent to change the direction of the connecting portion, and the end portions are connected to each other by making the connecting portion 3g annular. The connecting portion 3g and the inner surface of the outer peripheral portion of the shell 2 are not in contact with each other, and a gap 18 is provided.
[0035]
The other configuration of the pump 20 of the present embodiment is basically the same as that of the embodiment shown with reference to FIGS. 1 to 4, and the blade 3 is positioned with respect to the shell 2, and the protrusion 11 of the blade 3 is formed. By passing the semi-assembly fitted to the slit 10 of the core 4 through a furnace in a horizontal state, the wire-like brazing material held in the concave portion 12 of the projection 11 of the blade 3, the straight portion 3 e of the blade 3. A brazing material in the form of a wire placed near the outer end is brazed to the blade 3 and the core 4, and the blade 3 and the shell 2.
[0036]
In this connection type, since the blades 3 are connected to each other by the connection part 3g, there is a general advantage that the blade 3 can be easily positioned with respect to the shell 2 and the strength of the blade is enhanced by the connection part. Further, since the gap 18 is provided between the connecting portion 3g and the outer peripheral portion of the shell 2, the insertability of the blade 3 connected by the connecting portion 3g to the shell 2 is good, and the blade 3 is axially and radially oriented. Movement of the blade is allowed, and the strength of the blade can be further improved.
[0037]
Even if the connecting portion 3g of the blade 3 is brazed to the shell 2, there is almost no effect on the bonding strength between the blade 3 itself and the shell 2, so a gap is provided without contacting the connecting portion 3g and the shell 2. In this case, the connecting portion 3g can be prevented from being brazed to the shell 2, and the brazing material can be saved accordingly.
[0038]
In any of the above embodiments, the torque converter pump has been described. However, the present invention can be applied to a turbine of a torque converter, and can be widely applied to a fluid impeller of a fluid transmission device.
[0039]
【The invention's effect】
As is clear from the above description, according to the present invention, the brazing material is spread over the entire contact portion between the blade and the core where the projection of the blade is fitted in the slit, so that the blade and the core are not separated. By brazing and fixing without generating a joint portion, the blade and core can have sufficient joint strength with the fluid impeller.
[Brief description of the drawings]
FIG. 1 is a front view showing a pump according to an embodiment of a fluid impeller of the present invention.
2 is a cross-sectional view showing a method for assembling the pump of FIG. 1. FIG.
FIG. 3 is a cross-sectional view showing a continuation of the assembly method of FIG. 2;
4 is a plan view showing that a recess for holding a brazing material is provided in a projection of a blade that is a component of the pump of FIG. 1; FIG.
FIG. 5 is a cross-sectional view showing an example of a torque converter incorporating the pump of FIG. 1;
FIG. 6 is a cross-sectional view showing a pump according to another embodiment of the present invention.
[Explanation of symbols]
2 Shell 3 Blade 3a Inner edge 3b Outer edge 4 Core 5 Retainer 10 Slit 11 Protrusion 12 Recess 13, 14 Wiring brazing material 15 Subassembly 18 Gap 20 Pump

Claims (5)

A number of blades arranged radially with respect to the shell are positioned, the protrusions on the inner edge of the blades are fitted into the slits of the core, and the blade protrusions and the positions close to the outer ends are placed horizontally. In the fluid impeller in which the inner edge of the blade and the core and the outer edge of the blade and the shell are brazed by placing a brazing filler in a wire shape and heating,
Inner edge of the projection is provided so as to protrude from a portion of the core, further has a substantially upright in a substantially state where a same thickness and transversely to the blade and the blade, the further protrusion of the tip With a recess ,
Fluid impeller for a brazing material of positions of the projections fitted into the slits of the core is characterized in that is held in the recess.   The fluid impeller according to claim 1, wherein the recess has a depth to hold the brazing material.   The fluid impeller according to claim 1 or 2, wherein the concave portion is formed in a groove having a substantially parallel straight portion. The fluid impeller according to any one of claims 1 to 3, wherein a retainer for positioning an inner end of the blade with respect to the shell is welded to an inner peripheral side of the shell .   The blade is a connection-type blade in which outer edges of the blades are connected by an annular connection portion, and a gap is provided without contacting the connection portion and the shell. 5. The fluid impeller according to any one of 4 above.

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