JPS6313432Y2 - - Google Patents

Description

[Detailed Description of the Invention] This invention relates to a vane type vacuum pump, and in particular, to improvements in the structure of the end frame, cam ring, and plate.

First of all, this kind of conventional vane type vacuum pump is the first
2 and 2 will be explained.

That is, in FIG. 1 and FIG. 2, 1 is an end frame which is a bracket of an automotive alternator (not shown), 2 is a filler metal embedded in this end frame, and 3 is a part from the end frame 1 via a bearing 4. A shaft 5 supported and driven by a prime mover (not shown) is a rotor fixed to this shaft 3, and a plurality of vanes 6 (four in the diagram) radially disposed on this rotor 5. is slidably inserted into. Reference numeral 7 denotes a housing having a cylindrical inner wall eccentric to the centers of the shaft 3 and rotor 5, and this housing 7 is fixed to the end frame 1 with mounting bolts 8. Reference numeral 9 denotes an oil seal fixed to the filler metal 2 to keep the inside of the housing 7 airtight. 10 is a gasket for maintaining airtightness between the filler metal 2 and the housing 7. 11,1
Reference numerals 2 and 13 denote an inlet, an outlet, and an oil supply port provided in the housing 7, respectively.The intake port 11 is connected to a vacuum tank (not shown), and the oil supply port 13 is also connected to an oil pump (not shown). 2a is filler metal 2
This is a cylindrical cam ring that is installed in the housing 7 and is concentric with the housing 7.

Next, the operation of such a conventional device will be explained. First, when the shaft 3 rotates in the direction of the arrow, the vanes 6 fly outward due to the centrifugal force generated in the vanes 6, and rotate while sliding on the inner wall of the housing 7. This rotation of the vane 6 causes the air in the vacuum tank to be sucked in through the suction port 11 and discharged from the discharge port 12. Further, the oil supplied to the housing 7 from the oil supply port 13 lubricates the sliding surfaces of the vanes 6 and the rotor 5, and is discharged from the discharge port 12. Furthermore, when the shaft 3 rotates at a low speed such as during startup, the centrifugal force generated on the vane 6 is relatively small, and the protrusion of the vane 6 is suppressed.
comes into sliding contact with the outer periphery of the cam ring 2a provided on the filler metal 2 and is pushed up, making it possible to easily pop out.

As described above, in conventional vane-type vacuum pumps, although the end frame 1 is made of a light metal such as aluminum or aluminum alloy, it is made of a buried material such as cast iron to prevent the rotor 5 from wearing due to sliding. Gold is embedded, and due to its structure, the cam ring 2a must be provided on the end face of the embedded metal 2, and
Since there is a gap between the end frame 1 and the filler metal 2, the filler metal 2 is necessary to maintain airtightness inside the housing.
It was necessary to provide this even to the fixed part of the oil seal 9.

For this reason, casting to embed the filler metal 2 is difficult, and the defect rate due to movement of the filler metal 2 during casting is high.
The weight of the end frame 1 itself was also increased. In addition, machining such as cutting is required to smooth the surface of the filler metal 2, especially the side end surface that comes into sliding contact with the vane 6, and the outer circumferential surface of the cam ring 2a, but the center of the cam ring 2a and the center of the shaft 3 are offset. Since these processes require eccentric processing, the end frame 1 becomes expensive.

This idea was made to eliminate the above-mentioned drawbacks.The cam ring is integrally formed with the end frame, and the plate is positioned by engaging the inner circumferential surface of the plate with the outer circumference of the cam ring. At the same time, the outer periphery of this plate is clamped and fixed between the housing and the end frame, and furthermore, a lightweight and inexpensive vane type vacuum pump is constructed in which the vane is slidably contacted with the side view of this plate. This is what we provide.

An embodiment of this invention shown in FIGS. 3 and 4 will be described below.

In the figure, 14 is an end frame formed by die-casting or the like, 14a is a cam ring formed integrally with this end frame 14, and 15 is a ring-shaped plate formed by pressing sheet metal. , is disposed between the housing 7 and the end frame 14, and is integrally fixed to these members by mounting bolts 8. Also, at this time, the cam ring 14a is attached to the plate 15.
is set to protrude in the axial direction. 16
16a is a gasket for maintaining airtightness between the end frame 14 and the plate 15, and 16a is a groove provided in the end frame 14 for fixing the gasket 16.

The operation of the vacuum pump in such a configuration is basically the same as that of the conventional example, so a description thereof will be omitted.

By the way, in such a vane type vacuum pump, since the plate 15 is arranged on the sliding surface of the vane 6, the plate 15 can be formed only by pre-processing such as pressing, and post-processing after assembly, i.e. There is no need for eccentric processing. Further, since the outer circumferential surface of the cam ring 14a can be formed integrally with the end frame 14 by a casting technique such as a die casting method, it can be formed relatively smoothly, and the cam ring 14a can be formed integrally with the end frame 14 by a casting technique such as a die casting method. It only performs a driving action, and wear due to sliding contact between the vane 6 and the cam ring 14a is less likely to affect the vacuum characteristics, so some surface roughness can be tolerated. It becomes possible to completely omit machining after casting.

That is, by forming the cam ring 14a by integrally molding the end frame 14 and disposing the ring-shaped plate 15 on the sliding surface of the vane 6, the conventional filler metal 2 is no longer necessary.
It is possible to facilitate casting by eliminating any defects in the end frame 14 due to movement of the end frame 14, and
Eccentric processing of the filler metal 2 can be made unnecessary, and a lightweight and inexpensive device can be obtained.
Furthermore, a plate 1 is attached to the outer circumference of the cam ring 14a.
plate 15 by engaging the center hole of 5.
This also has the advantage of making it easier to assemble the device.

As explained above, this invention has a structure in which a cam ring for pressing the vane is formed integrally with the end frame, and a ring-shaped plate is arranged on the sliding surface of the vane. It facilitates casting and eliminates the need for eccentric machining of the plate and cam ring. In addition, the inner periphery of the plate engages with the outer periphery of the cam ring for positioning, and the outer periphery is sandwiched between the housing and the end frame. Since it is configured to be fixed, assembly is easy, and there are practical effects such as being able to obtain a lightweight and inexpensive vane type vacuum pump.

[Brief explanation of the drawing]

Fig. 1 is a side sectional view showing a conventional vane type vacuum pump, Fig. 2 is a sectional view taken along the - line in Fig. 1, and Fig. 3 shows a vane type vacuum pump which is an embodiment of this invention. The side sectional view, FIG. 4 is a sectional view cut along the - line in FIG. 3. In the figure, 3 is the shaft, 4 is the bearing, 5 is the rotor, 6 is the vane, 7 is the housing, 8 is the mounting bolt, 9 is the oil seal, 11 is the suction port, 12 is the oil filler port, 13 is the discharge port, and 14 is the end frame,
14a is a cam ring, 15 is a plate, 16 is a gasket, and 16a is a groove. In addition, in the figures, the same reference numerals indicate the same or corresponding parts.

Claims (1)

[Scope of utility model registration request] A housing formed in a cylindrical shape having an inlet and an outlet, a rotating shaft rotatably provided in the housing eccentrically with respect to the inner peripheral surface of the cylindrical shape, a frame rotatably supporting the rotating shaft, and the above-mentioned A rotor is formed to be eccentric to the cylindrical inner circumferential surface of the housing and concentric with the rotation axis, and is attached to the rotor so as to be slidable in the radial direction and always slides on the cylindrical inner circumferential surface of the housing. A vane that is in contact with the frame and can pressurize fluid from the suction port to the discharge port, and is formed integrally with the frame so as to be concentric with the cylindrical inner circumferential surface of the housing, and the inner circumferential end surface of the vane is arranged in a radial direction. a cam ring that can be pressed against the cam ring, an inner circumferential surface of which is positioned by engaging with the outer circumference of the cam ring, an outer circumferential portion of which is clamped and fixed between the housing and the frame, and the vane is slidably contacted with the side surface of the cam ring; A vane-type vacuum pump with a ring-shaped plate.