JPH074887U - Oil pump rotor centering structure - Google Patents

Abstract

(57) [Abstract] [Purpose] There is no risk of damage to the rotor during assembly, the outer diameter of the rotor can be reduced, and no parts for centering the rotor are required. To provide a rotor centering structure. The rotor 6 can be preliminarily centered on the inner circumference of the rotor 6 by coming into contact with or close to the outer circumference of the stator shaft 2a, and the rotor drive shaft 10 can be slightly aligned from the outer circumference of the stator shaft 2a in a coupled state. A centering surface 6b that forms the minimum inner diameter r2 of the rotor 6 that is arranged at a distance is formed.

Description

[Detailed description of the device]

[0001]

[Industrial applications]

 The present invention relates to an oil pump used in an automatic transmission, and more particularly to a structure for centering a rotor when a pump is assembled.

[0002]

[Prior art]

 Conventionally, as a rotor centering structure of an oil pump, for example, the one described in Japanese Utility Model Laid-Open No. 62-47789 (first conventional technology) or the one described in Japanese Patent Laid-Open No. 58-155289. (Second related art) is known.

In the first prior art, as shown in FIG. 7, a centering protrusion 03 is formed in a radial direction on a stator shaft 02 that is integrally formed with a pump cover 01 and supports a stator of a torque converter. In the vicinity of the inner circumference of the rotor 06, there is formed a flange 05 that can approach or come into contact with the centering protrusion 03 in the radial direction, and the inner circumference of the rotor 06 has a non-flat surface. A circular rotor center hole 06a was formed, and the tip end of the rotor drive shaft 08 welded to the impeller shell 07 of the torque converter was formed so that it could be fitted into the rotor center hole 06a.

When the rotor drive shaft 08 is inserted into and coupled to the rotor 06, the flange 05 of the rotor 06 is brought into contact with or close to the centering projection 03 of the pump cover 01 in advance to establish a preliminary centering state. Then, the rotor drive shaft 08 is inserted from the pump housing 09 side, and its tip end is fitted into the rotor center hole 06a, whereby the final centering state is obtained. At this time, the flange 05 of the rotor 06 is slightly separated from the centering protrusion 03.

Further, the second prior art has a structure in which a ring-shaped centering member 010 is press-fitted into the base of the stator shaft 02 of the pump cover 01, as shown in FIG. The centering member 010 contacts the rotor driving shaft 08 with the rotor center hole 06a before the rotor driving shaft 08 is connected to the rotor center hole 06a by bringing the outer circumferential side of the centering member 010 into contact with or close to the inner circumference of the flange 05 protruding from the rotor 06. The preliminary centering of 06 is performed. The same components as those of the first conventional technique are designated by the same reference numerals and the description thereof will be omitted.

[0006]

[Problems to be solved by the device]

 However, the above-mentioned conventional technique has the following problems. That is, in both the first and second conventional techniques, the flange 05 is engaged with the centering projection 03 or the centering member 010 in the radial direction to preliminarily center the rotor 06. When the motor is assembled by moving it axially with respect to the stator shaft 02, the flange 05 may ride on the centering projection 03 or the centering member 010 in the axial direction. When assembled with the pump housing 09, the rotor 06 might be damaged. Therefore, in order to prevent this from happening, it is necessary to carefully position and assemble the parts, and improvements have been desired in terms of workability.

Further, in the first prior art, since the rotor 06 has the flange 05, the outer diameter dimension of the rotor 06 is increased by the width of the flange 05, and the turning radius of the vane is increased. Efficiency deteriorates.

Further, in the second conventional technique, the centering member 010 is necessary for centering, and the number of parts is increased by that much, workability for assembling is deteriorated, and cost is increased.

The present invention has been made by paying attention to the above-mentioned conventional problems. There is no fear of damaging the rotor during assembly, the outer diameter of the rotor can be reduced, and the rotor It is an object of the present invention to provide a rotor centering structure for an oil pump that does not require any part for centering.

[0010]

[Means for Solving the Problems]

 To achieve the above object, the present invention provides a rotor in a space formed between a pump housing and a pump cover having a stator shaft that supports a stator of a torque converter. The inner peripheral portion and the rotor drive shaft are rotationally coupled by engaging the engaging pawl formed on either one with the recess or pawl formed on the other, and the rotor drive shaft rotates the rotor. In an oil pump that performs a pumping action by rotating the rotor pump, the part that constitutes the minimum inner diameter of the rotor is formed so as to be arranged slightly apart from the outer circumference of the stator shaft when connected to the rotor drive shaft. Further, a centering portion for preliminarily centering the rotor is formed in contact with or close to the outer circumference of the stator shaft.

[0011]

[Action]

 When assembling the rotor, when assembling the rotor to the pump cover, the centering part that forms the minimum inner diameter of the rotor is inserted into the stator shaft and brought into contact with or close to the outer periphery of the rotor to prepare for preliminary centering. And In this way, since the parts for performing the preliminary centering on the rotor side and the stator shaft side do not overlap in the axial direction, the rotor does not ride on the part on the pump cover side in the axial direction. The rotor will not be damaged when the ring is assembled.

Further, the rotor drive shaft is coupled to the rotor in the above-mentioned preliminary centering state. That is, the engaging claws formed on either one of the rotor and the rotor drive shaft are engaged with the recesses or claws formed on the other side to couple them in the rotational direction. Then, in this combined state, the centering portion of the rotor is slightly separated from the outer periphery of the stator shaft and is in a close state. Therefore, the rotor rotates without contacting the stator shaft.

[0013]

【Example】

 Embodiments of the present invention will be described with reference to the drawings.

FIG. 2 is a sectional view showing a main part of an automatic transmission to which a rotor centering structure of an oil pump according to a first embodiment of the present invention is applied, in which TC is a torque converter and OP is an oil pump. The oil pump OP has a pump housing 1 and a pump cover 2. The pump cover 2 is integrally formed with a stator shaft 2a for supporting a stator 3 of the torque converter TC. The pump housing 1 and the pump cover 2 are fastened with bolts 11, and a cam ring 4 and a vane 5 inscribed therein are supported in a space formed between the two so as to be capable of advancing and retracting in the radial direction. And a piston 7 for pressing the cam ring 4.

FIG. 3 is a sectional view taken along the line S3-S3 in FIG. 2, in which the cam ring 4 is supported by a pin 4a so as to be swingable in the directions of arrows a and b in a part of its outer circumference. The swing of the cam ring 4 is determined by the balance between the hydraulic pressure applied to the piston 7 and the urging force of the spring 8, and the eccentric amount of the cam ring 4 controls the pump displacement.

Further, as shown in the drawing, three rotor side fitting claws 6a are provided on the inner circumference of the rotor 6 so as to project in the axial direction while forming an angle of approximately 60 ° with each other in the circumferential direction. ing. That is, as shown in the perspective view of FIG. 4, these rotor-side fitting claws 6a respectively have three shaft-side fitting claws 10a formed at the tip of the rotor drive shaft 10 between them. It is formed to be inserted and fitted. The rotor drive shaft 10 is welded to the impeller shell 9 of the torque converter TC as shown in FIG.

As shown in FIG. 1, the inner peripheral portion of the rotor 6 at the base end of the rotor-side fitting claw 6 a (this is referred to as the maximum inner diameter r 1 of the rotor 6) is the rotor drive shaft 10. Is formed to fit the outer peripheral surface of the. The shaft-side fitting claw 10a is formed with a curved surface 10b so that the diameter thereof becomes slightly smaller toward the tip, as shown in the figure.

Further, the tip end surface of the rotor side fitting claw 6a is a centering surface 6b as a centering portion in the claims, and the minimum inner diameter r2 of the rotor 6 constituted by the centering surface 6b is As shown in FIG. 1 or 3, the diameter of the stator shaft 2a is slightly larger than the outer diameter of the stator shaft 2a.

Next, a procedure for assembling the oil pump OP will be described.

First, the piston 7, the cam ring 4, the rotor 6, etc. are assembled to the pump housing 1. Then, the pump cover 2 is put on the pump housing 1. At this time, the stator shaft 2a formed integrally with the pump cover 2 is inserted into the inner circumference of the rotor 6, and in this state, the centering surface 6b at the tip of each rotor-side fitting claw 6a of the rotor 6 is aligned with the stator shaft 2a. When the rotor 6 comes into contact with or comes close to the outer periphery thereof, a preliminary centering state in which the axis of the rotor 6 and the axis of the stator shaft 2a substantially coincide with each other is obtained. At this time, there is no portion of the pump cover 2 near the base end of the stator shaft 2a that overlaps the rotor 6 in the axial direction, and the rotor 6 does not ride up. Since the rotor 6 is simply inserted into the stator shaft 2a, it is not necessary to use a special jig. By the way, according to the assembling procedure for assembling the pump cover 2 to the rotor 6 assembled to the pump housing 1 as described above, conventionally, a jig for positioning the rotor 6 when assembling the pump cover 2 is used. It is necessary (for example, see "Maintenance Manual NISSAN Automatic Transaxle RE5R01A Model" August 1989, Nissan Motor Co., Ltd., B-8, pages 1,82).

After that, the bolt 11 is fastened to finish the assembling of the oil pump OP, but the rotor 6 does not ride on the step of the pump cover 2 or the like as described above, so the rotor 6 is damaged at the time of fastening. There is no such thing.

Then, as described above, the rotor drive shaft 10 is coupled to the rotor 6 in the preliminary centering state. That is, by inserting the shaft side fitting claw 10a at the tip of the rotor drive shaft 10 between the rotor side fitting claws 6a, the outer circumference of the rotor drive shaft 10 is fitted to the maximum inner diameter r1 of the inner circumference of the rotor 6. Fit. At this time, since the rotor 6 is in the pre-centering state, the size of the rotor 6 is twice as large as the gap h set between the centering surface 6b and the stator shaft 2a in FIG. 1 (a). Although there is a possibility that the axial center is displaced in the radial direction, as shown in the figure, the curved surface 10b is formed at the tip of the shaft-side fitting claw 10a and is tapered. Even if there is, the tip of the rotor drive shaft 10 can be easily inserted into the inner circumference of the rotor 6. Further, as shown in FIG. 1B, when the rotor drive shaft 10 is further inserted into the rotor 6 from this state, the positions thereof are displaced from each other in the radial direction based on the dimensional change in the radial direction due to the curved surface 10b, and the shafts are displaced from each other. The minds will agree.

Then, at the end of the fitting, the centering surface 6a of the rotor 6 is in a state of being separated from the stator shaft 2a with a gap h as shown in the drawing. Therefore, the rotor 6 rotates without contacting the stator shaft 2a.

As described above, in the structure of the first embodiment, the effects listed below can be obtained.

At the time of assembling the oil pump OP, it is only necessary to insert the stator shaft 2a into the inner circumference of the rotor 6, so that it is not necessary to use a jig or the like, and the assembling workability is excellent.

At the time of preliminary centering, the centering surface 6a, which is the minimum inner diameter r2 of the rotor 6, and the outer diameter of the stator shaft 2a are merely brought into contact with or brought close to each other. Since there is no step portion that rides up in the axial direction, the rotor 6 will not be damaged even if the pump housing 1 is assembled and the bolts 11 are tightened.

A separate member for centering is unnecessary, workability in assembling is good, and cost is not increased. A curved portion 10b is formed on the outer peripheral portion of the shaft side fitting pawl 10a of the rotor drive shaft 10. Therefore, even if the axial center is displaced in the radial direction when the rotor 6 is preliminarily centered, it is easy to insert the rotor drive shaft 10 into the inner circumference of the rotor 6, and the workability is excellent.

Next, a second embodiment shown in FIGS. 5 and 6 will be described. In describing the second embodiment, the same components as those in the first embodiment are designated by the same reference numerals in the drawings, and the description thereof will be omitted.

As shown in FIG. 5, the second embodiment is an example in which the entire inner circumference of the rotor 26 is formed in a size close to the stator shaft 2a and the entire inner circumference is used as a centering surface 26b. Then, a fitting hole 26c is formed at two positions slightly outward in the radial direction from the centering surface 26b, and the fitting hole 26c is formed at the tip of the rotor drive shaft 210 as shown in FIG. The shaft-side fitting claw 210a is fitted to couple the rotor 26 and the rotor drive shaft 210. Therefore, also in the second embodiment, the same operational effect as in the first embodiment can be obtained.

Although the embodiment has been described above, the specific configuration is not limited to this embodiment, and even if there is a design change or the like within a range not departing from the gist of the invention, the invention is included in the invention. . For example, in the embodiment, as the centering portion, the centering surface 6b constituted by the tip end surface of the rotor side fitting claw 6a or the centering surface 26b constituted by the entire inner circumference of the rotor 16 is shown. The centering portion is not limited as long as it can perform preliminary centering in contact with or close to the outer circumference of the stator shaft 2a and also constitutes the minimum inner diameter of the rotor 6, and thus is formed of a surface. Alternatively, the protrusion may be a protrusion or a ridge capable of contacting the stator shaft 2a with a dot or a line.

Further, in the embodiment, as an example of the assembling work, the example in which the pump cover 2 is assembled to the rotor 6 assembled to the pump housing 1 side is shown, but the rotor may be assembled to the pump cover 2. .

[0032]

[Effect of device]

 As described above, in the rotor centering structure of the oil pump of the present invention, since the preliminary centering is performed at the centering portion of the inner diameter of the rotor and the outer circumference of the stator shaft, the oil pump At the time of assembly, just insert the status shaft into the inner circumference of the rotor and it will be in the pre-centering state. At this time, there is no need to use jigs, etc. There is no need for a stepped portion on the cover side to allow the rotor to ride up, so the effect of preventing damage to the rotor due to such riding up is obtained, and a separate centering member is not required. However, this also improves the workability in assembling, and has the effect that there is no cost increase due to this member. Further, since the inner circumference of the rotor is close to the stator shaft, the inner diameter and the outer diameter of the rotor can be reduced, which also has the effect of reducing the radius of gyration of the vane and improving the mechanical efficiency. .

[Brief description of drawings]

FIG. 1 is a sectional view showing a rotor centering structure of an oil pump according to a first embodiment of the present invention.

FIG. 2 is a sectional view showing a main part of an automatic transmission to which the structure of the first embodiment is applied.

FIG. 3 is a sectional view taken along line S3-S3 of FIG. 2 showing the structure of the first embodiment.

FIG. 4 is a perspective view showing a rotor drive shaft of the first embodiment structure.

FIG. 5 is a cross-sectional view showing the main parts of the second embodiment structure.

FIG. 6 is a perspective view showing a rotor drive shaft of a second embodiment structure.

FIG. 7 is a cross-sectional view showing a conventional technique.

FIG. 8 is a sectional view showing a conventional technique.

[Explanation of symbols]

 TC torque converter OP oil pump 1 pump cover 2 pump housing 2a stator shaft 3 stator 6 rotor 6a rotor side fitting claw (engaging claw) 6b centering surface (centering part) 26c fitting hole (recess) 10 rotor drive shaft 10a Shaft side fitting claw 210a Shaft side fitting claw

Claims (1)

[Scope of utility model registration request] 1. A rotor is provided in a space formed between a pump cover having a stator shaft supporting a stator of a torque converter and a pump housing, and an inner peripheral portion of the rotor and a rotor drive shaft are provided. In an oil pump in which an engaging claw formed on one side is coupled in a rotational direction by engaging a recess or a claw formed on the other side, the rotor drive shaft rotates the rotor to perform a pumping action. The portion forming the minimum inner diameter of the rotor formed so as to be arranged at a slight distance from the outer circumference of the stator shaft when connected to the rotor drive shaft is in contact with or close to the outer circumference of the stator shaft before the connection. A centering portion for preliminarily centering the rotor is formed.