JPH0783176A - Vane pump - Google Patents

Abstract

PURPOSE:To improve the seizuring resistance of a rotor, reduce the side clearance in a pump cartridge, and improve the performance of the volumetric efficiency of a vane pump. CONSTITUTION:A pump component 13 consists of a rotor 5 and a cam ring 17 to constitute a pump cartridge 19, side plates 20 on both sides and a pressure plate 21. The tip part of a drive shaft 16 is spline connected to the rotor. A spline hole 40 of the rotor is formed to the shape by semi-circuit, curved surfaces or the like having the continuous amount of addendum modification of 0.01-0.03mm, i.e., the manufacturing allowance of the spline hole along the angle of inclination of the drive shaft 16 having the spline part 43 to be at least engaged therewith. In addition, the spline part 40 of the drive shaft 16 is engaged by keeping the engagement length in the axial direction at the minimum length to secure the durable strength.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a vane pump suitable for use in, for example, a power steering device for reducing the steering force of an automobile.

[0002]

2. Description of the Related Art This type of vane pump is suitable for use as a hydraulic power source or the like in a power steering device, and many types of vane pumps having various structures have been proposed.

An example thereof will be briefly described with reference to FIG. 4. A vane pump generally designated by reference numeral 10 is a front body 11 and a rear body 12 which constitute a pump body.
Is equipped with. The rear body 12 has a substantially cup shape, and a storage space 14 for storing and arranging the pump component 13 therein is formed therein, and the front body 11 is combined so as to close the open end of the storage space 14. It is integrated. The front body 11 is rotatably supported by bearings 16a and 16b in a state in which a drive shaft 16 for externally rotating and driving a rotor 15 that is a rotor of the pump component 13 penetrates.

Reference numeral 17 has a substantially elliptical inner cam surface 17a in which the rotor 15 having the vanes 15a is housed and arranged, and a pair of pump chambers 18, 18 (only one of which is provided between the cam surface 17a and the rotor 15). The cam cartridge 17 forms a pump cartridge 19 by the cam ring 17 and the rotor 15 having the vanes 15a.

Reference numeral 20 denotes a side plate which is arranged in pressure contact with the front body 11 side of the pump cartridge 19, and 21 denotes a rear body 12 of the pump cartridge 19.
The pressure plates are arranged in pressure contact with each other and are stacked.
9 and 9 form the pump component 13. In addition, both these plates 20 and 21 and the cam ring 1
7 is integrally fixed to the front body 11 side by a bolt 23 while being positioned in the rotational direction by a positioning pin 22.

Reference numeral 25 denotes a storage space 14 for the rear body 12.
In the pressure chamber on the pump discharge side that is formed on the bottom side in
The pressure on the discharge side of the pump is applied to the pressure plate 21. 26 is this pump discharge side pressure chamber 2
5 is a passage on the pump discharge side that is formed in the pressure plate 21 that guides the pressure oil from the pump chamber 18.

Reference numeral 27 denotes a pump suction side passage formed in the rear body 12 and the front body 11 so as to guide the suction side fluid from the suction port 28 provided in a part of the rear body 12 to the pump chamber 18. 27 is a pump suction opening 29 formed in the side plate 20.
It is connected to the pump chamber 18 via.

Reference numeral 30 is provided inside the rear body 12 and is connected to the pressure chamber 25 on the pump discharge side through a passage 30a, which is connected to the pump suction passage 28 near the suction port 28.
And a flow control valve for selectively controlling the discharge fluid from the pump chamber 18 to a predetermined flow rate. Reference numeral 31 denotes a part of the flow control valve 30 that is partially recirculated to the suction side. A discharge port for feeding hydraulic equipment such as a device (indicated by PS in the figure).
Is provided on a side portion of the rear body 12 in a state having a metering orifice 32 at a connection portion with respect to the storage space 14.

As is apparent from FIG. 4, the vane pump 10 also has components other than those described above, but these are well known in the prior art, and the description thereof will be omitted.

The vane pump 10 having the above structure
According to the above, the rotor 15 is rotationally driven by the drive shaft 16 while moving the vanes 15 a in and out, so that the pressure oil from the suction port 28 is transferred to the passage 27 and the opening 29.
After being sucked into the pump chamber 18 and discharged from the discharge side passage 26 to the pump discharge side pressure chamber 25, the entire amount is discharged from the discharge port 31 to the power steering device PS or the like at a predetermined pressure or lower, and is fed. Further, at a pressure equal to or higher than a predetermined pressure, a part of the oil is recirculated to the suction side by the flow control valve 30, and the remaining pressure oil is passed from the pump discharge side pressure chamber 25 to the clearance passage between the outer peripheral portion of the pump component 13 and the inner wall portion of the storage space 14. Three
3. Metering orifice 32 that opens further
After that, it is discharged from the discharge port 31.

[0011]

By the way, in the vane pump having the above-mentioned conventional structure, the mechanical structure between the rotor 15 constituting the pump cartridge 19 as the pump component 13 and the drive shaft 16 for rotationally driving the rotor 15 is provided. The following problems occur in various power transmission parts.

That is, as is apparent from FIGS. 4 to 6 (a) and 6 (b), the rotor 15 and the drive shaft 16 described above are generally connected and coupled by spline connection. There is. In the figure, 40 is a spline hole formed by a plurality of troughs 41 and a plurality of crests 42 formed in the shaft hole of the rotor 15, and 43 is a spline hole 40 so as to mesh with the troughs 41 and crests 42 of the spline hole 40. It is a spline portion formed by a mountain portion 44 and a valley portion 45 formed at the tip of the drive shaft 16.

However, in the above-mentioned spline coupling portion, the axis of the drive shaft 16 is relative to the axis of the rotor 15 due to a manufacturing error between the spline hole 40 and the spline portion 43, a tilt due to a gap in the bearing 16b of the drive shaft 16, and the like. As shown by the arrow A in FIG. 5, it was relatively displaced. Then, in such a state, the spline portion 43 on the shaft 16 side is in contact with the spline hole 40 on the rotor 15 side at the positions shown by B and B in FIG. Plates on both sides at the positions indicated by C and C in (b) of
There has been a problem that it is likely to cause galling etc. due to partial contact with 0 and 21.

In particular, the problem of such galling is remarkable because a part of the driving torque is converted into the surface pressure on the side surface of the rotor 15 via the shaft 16, and if this is taken, the galling of the rotor 15 will occur. The portions C and C were easily seized on the plates 20 and 21 on both sides thereof.

Moreover, in the recent vane pump 10 for a power steering device, there is a great demand for increasing the capacity and increasing the pressure. For this reason, the pump component 13, that is, the pump cartridge 19 by the rotor 15 and the cam ring 17 is required. It is desired to prevent internal leakage from between the side plate 20 and the pressure plate 21 on both sides thereof, and it is possible to increase the surface pressure between the joint surfaces of these members and to integrally configure them. Needed. From this, the rotor 1 of the shaft 16 described above
The galling problem due to the displacement due to the axis deviation with respect to 5 is
This leads to an even larger seizure problem, and it is necessary to take measures against such seizure.

As a countermeasure against such seizure, both side plates 20 and 2 in the pump cartridge 19 are provided.
Although the side clearance with 1 may be expanded to increase the amount of lubricating oil, internal leakage from the inside of the pump chamber 18 becomes large, volumetric efficiency deteriorates, and it becomes impossible to respond to the aforementioned large capacity and high pressure. It was a thing.

Further, a measure has been considered in which the engagement length of the spline portion 43 of the shaft 16 with respect to the spline hole 40 in the axial direction is shortened to relatively reduce the displacement due to the above-mentioned fall. , (A) and (b) of FIG.
As is clear from the above, there is a limit to the durability strength of the spline coupling portions 40 and 43 during transmission of the driving torque, and no further effect can be expected.

Further, in order to absorb the displacement due to the tilt of the shaft 16 described above, the ridge portion 44 forming the spline portion 43 at the tip end portion of the shaft 16 is appropriately expanded in the tooth trace direction in order to improve the tooth contact. To turn on
It is considered to take measures such as so-called crowning, but such a spline portion 43
Since the processing machine is limited and the cost becomes high, it is desired to take some measures to eliminate these problems.

The present invention has been made in view of such circumstances, and a pump cartridge as a pump component,
In particular, it is possible to improve the seizure resistance to both side plates of the rotor, reduce the side clearance of the pump cartridge, prevent internal leakage, improve the pump volume efficiency performance, and meet the demands for large capacity and high pressure. The purpose is to obtain a vane pump having a simple structure and a low cost.

[0020]

In order to meet such a demand, a vane pump according to the present invention has a cam ring which constitutes a pump cartridge by accommodating a rotor having a vane, and a side arranged in pressure contact with both sides thereof. A drive shaft having a plate and a pressure plate, and a drive shaft tip portion inserted into the rotor from one side, spline-coupled, and at least a spline portion of the spline hole of the rotor that meshes with the spline hole; There is a manufacturing error of 0.01 at the time of manufacturing this spline hole along the inclination angle of the drive shaft having a tip end.
The minimum length to form a spline part of the drive shaft on the shape of an arc, curved surface, etc. with a continuous dislocation amount of about 0.03 mm, and the axial engagement length to ensure durability. It is designed to engage with each other.

[0021]

According to the present invention, the spline hole of the rotor is formed along the inclination angle of about 0.1 to 0.2 ° of the drive shaft having the spline portion which meshes with the spline hole. Is formed by a circular arc or curved surface with a continuous dislocation amount, and the spline part of the shaft is meshed with the axial meshing length with a minimum length considering durability strength. Against this, relative displacement due to tilting of the drive shaft is prevented, seizure resistance to both side plates of the rotor is improved, side clearance of the pump cartridge is reduced, internal leakage is prevented, and pump volume efficiency performance is improved.
It is possible to meet the demands for large capacity, high pressure, and compatibility.

[0022]

1 to 3 show an embodiment of a vane pump according to the present invention. In these figures, the same or corresponding parts as those in FIG. Is omitted.

Now, according to the present invention, in the vane pump 10 as described above, as is clear from FIGS. 1 to 3, among the spline holes 40 of the rotor 15, at least the spline portion 43 meshing with the spline hole 43 is provided. Along with the inclination angle θ of about 0.1 to 0.2 ° of the drive shaft 16 at the tip portion, a continuous dislocation amount of about 0.01 to 0.03 mm, which is a manufacturing error when manufacturing the spline hole 40, is set. The shift gear portion 50 is formed in a shape having a circular arc, a curved surface, or a linear portion in a part thereof, and the spline portion 43 of the drive shaft 16 is meshed with the spline portion 43 in the axial direction at a minimum length to secure durability strength. It has a feature in that it engages with the length.

Here, the dislocation gear portion 50 described above is shown in FIG.
As is clear from the solid and wavy lines in
6 In the fitting portion of the spline portion 43 at the tip end portion to the spline hole 40, a curved surface such as an arc or a quadratic curve is formed from the tip end of the spline portion 43 to the end surface side of the rotor 15 on the shaft 16 insertion side. The portion near the end face of the rotor 15 may be formed linearly.

According to this structure, the spline hole 40 of the rotor 15 has a drive shaft 16 having a spline portion 41 meshing with the spline hole 40.
It is formed by an arc or curved surface having a continuous dislocation amount of about 0.01 to 0.03 mm, which is an error in manufacturing the spline hole 40, along an inclination angle of about
Although the structure is extremely simple, excellent in workability, and inexpensive, relative displacement due to tilting of the drive shaft 16 with respect to the rotor 15 is prevented, and both side plates 20, 21 of the rotor 15 are prevented. The seizure resistance of the pump cartridge can be improved, the side clearance of the pump cartridge 19 can be reduced, internal leakage can be prevented, and the pump volumetric efficiency performance can be improved to meet the demands of large capacity, high pressure, and compatibility. .

In particular, the rotor 15 having the spline holes 40 formed by the troughs 41 and the peaks 42 due to the continuous dislocation as described above can be manufactured by sintering or the like, and the performance is improved without increasing the cost. Can be done, and its advantages are great.

With such a construction, the pump cartridge 19 in the pump component 13, especially the rotor 15
Seizure resistance to both side plates 20 and 21 of the pump cartridge can be greatly improved, the side clearance of the pump cartridge 19 can be reduced as much as possible, internal leakage from the pump chamber 18 can be prevented, and pump volume efficiency performance can be improved. Further, there are advantages that a large capacity and a high pressure can be achieved, and that the structure is simple and the cost is low.

The present invention is not limited to the structure of the embodiment described above, and the shape, structure, etc. of each part of the vane pump 10 can be freely modified or changed, and various modifications can be considered. .

Further, the vane pump 10 having the above-described structure is not limited to the structure of the above-described embodiment, but may be applied to various devices and devices other than the power steering device described in the above-described embodiment. Not to mention good things.

[0030]

As described above, according to the vane pump of the present invention, among the spline holes of the rotor, 0.1 to 0.2 of the drive shaft having at least a spline portion meshing with the spline hole at the tip thereof. There is a manufacturing error of 0.01 at the time of manufacturing this spline hole along the inclination angle of about °.
The minimum length to form a spline part of the drive shaft on the shape of an arc, curved surface, etc. with a continuous dislocation amount of about 0.03 mm, and the axial engagement length to ensure durability. Since it is engaged with each other, it is possible to prevent relative displacement due to tilting of the drive shaft with respect to the rotor and to prevent seizure on both side plates of the rotor, despite the fact that it is easy to process, simple and inexpensive. Improvements, reduction of side clearance of pump cartridge, prevention of internal leakage and improvement of pump volume efficiency performance, and various excellent effects of being able to meet demands such as large capacity, high pressure, and compatibility Play.

[Brief description of drawings]

FIG. 1 is a schematic cross-sectional view of a main part configuration showing an embodiment of a vane pump according to the present invention.

FIG. 2 is a sectional view taken along line II-II in FIG.

FIG. 3 is a schematic diagram showing a main part of the present invention.

FIG. 4 is a schematic cross-sectional view showing a schematic configuration of the whole vane pump to which the present invention is applied.

FIG. 5 is a schematic cross-sectional view showing a conventional spline coupling portion between a rotor and a drive shaft.

6A and 6B show a conventional spline coupling portion, FIG. 6A is a schematic sectional view, and FIG. 6B is a side sectional view thereof.

[Explanation of symbols]

 10 vane pump 11 front body 12 rear body 13 pump constituents 14 storage space 15 rotor 15a vane 16 drive shaft 16a bearing 16b bearing 17 cam ring 17a cam surface 18 pump chamber 19 pump cartridge 20 side plate 21 pressure plate 25 pump discharge side pressure chamber 26 pump Discharge side passage 27 Pump suction side passage 40 Spline hole 41 Valley 42 Crest 43 Spline part 44 Crest 45 Valley 50 Transposed gear

Claims (1)

[Claims] 1. A pump component comprising a cam ring, which constitutes a pump cartridge by accommodating a rotor having a vane, and side plates and pressure plates arranged in pressure contact with both sides of the cam ring, and one side of the rotor. In a vane pump in which the tip of the drive shaft inserted from above is spline-coupled, the spline is formed along the inclination angle of the drive shaft that has at least the spline part that meshes with at least one of the spline holes of the rotor. The drive shaft spline is formed in a shape with a continuous amount of dislocations that is close to the error when manufacturing the hole, and the spline part of the drive shaft is meshed with this spline hole in the minimum axial direction to obtain durable strength. A vane pump characterized by being formed so as to mesh with each other.