JPS647263Y2 - - Google Patents

Description

[Detailed explanation of the invention] (Industrial application field) This invention is a master cylinder for brakes or clutches, which is driven by an automobile engine.
This invention relates to an improvement in an automobile vacuum pump that is coaxially connected to a generator, among automobile vacuum pumps that generate the negative pressure necessary to operate mechanisms such as door opening/closing devices and various actuators.

(Prior Art) Automotive vacuum pumps have conventionally been configured to be driven by a running engine via a V-belt. In many cases, the vacuum pump 1 and the generator 2 are combined and driven by a single shaft. That is, the rotor of the generator 2 is rotated by a rotating shaft having a pulley 3 fixed to one end, which is rotated by the traveling engine via a V-belt (not shown), and at the same time, the rotor of the vacuum pump 1 is also rotated. It is something.

As shown in FIGS. 2 to 4, the structure of the vacuum pump 1 includes a plurality of grooves 7, 7 formed on the circumferential surface of a casing 6, which is formed by closing the opening of a bottomed short cylindrical main body 4 with a plate 5. A rotor 9 with a vane 8 inserted therein is eccentrically provided, and the rotor 9 is rotated within the casing 6 by a shaft 10 inserted through a circular hole 18 bored in the plate 5 at a position off the center of the casing 6. It is something. An intake port 11 and a discharge port 12 are provided on the upper and lower surfaces of the casing 6, respectively, and when the rotor 9 is rotated in the direction of arrow a in FIG. It is discharged from the outlet 12, thereby creating a negative pressure in the space connected to the intake port 11. As shown in FIG. 2, the outer circumferential surface of the rotor 9 and the inner circumferential surface of the casing 6 are closest to each other at the X portion located slightly behind the discharge port 12 in the rotational direction of the rotor 9, and the inside of the casing is It is lubricated by oil sent from the oil supply port 13 shown in FIG. 3 and is kept airtight.

The vacuum pump 1 connected to the generator 2 is constructed and operates as described above, but there is a slight difference in the distance between the outer circumferential surface of the rotor 9 and the inner circumferential surface of the casing 6 at point X, where they are closest to each other. Since this significantly affects the performance of the vacuum pump, it is necessary to ensure that this additional distance is exactly as designed. However, in the case of a vacuum pump coupled to the generator 2, the shaft 10 is the same body as the shaft of the generator 2, so it is necessary to accurately attach the casing 6, especially the main body 4, to the casing of the generator 2. . For this reason,
Conventionally, as shown in FIG. 3, a protruding ridge 14 formed on the outer surface of the plate 5 is fitted into a recess 15 of the casing of the generator 2 with a spigot, and as shown in FIG. The folded wall 16a of the flange 16 formed in the direction is fitted with a pilot on the outer peripheral surface of the plate 5 as shown in FIG. I was trying to attach it to.

(Problem to be Solved by the Invention) However, when positioning the main body 4 with respect to the generator 2 in this way by fitting two pilot holes through the plate 5, the ridges 14 abut each other at each pilot fitting portion. The outer peripheral surface of the recess 15, the inner surface of the folding wall 16a, and the plate 5.
It is necessary to accurately finish the four surfaces of the outer circumferential surface, and even if the errors in the two abutment surfaces are superimposed, the minute distance at the above-mentioned X point must be within the allowable range. Therefore, each contact surface must be machined extremely accurately, which increases manufacturing costs.

The automotive vacuum pump of the present invention eliminates the drawbacks of conventional products as described above.

(Means for Solving the Problems) This invention provides a pump casing that includes a short cylindrical main body 4 with a bottom, a plate 5 having a circular hole 18 through which the shaft 10 is inserted, and a plate 5 that closes the opening of the main body 4. A flange 16 is formed by protruding from the main body 4 of the casing 6, and the height H of the folded wall 16a formed at the end of the flange is bent toward the plate 5 side. The thickness is made larger than t, and the inner surface of this folded wall 16a is fitted with a spigot into the outer circumferential surface 17b of the convex portion 17 formed on the outer surface of the generator casing, thereby connecting the main body 4 to the generator casing. The above-mentioned problems have been solved by providing a vacuum pump for automobiles characterized by the following features.

(Function) The height H of the folded wall 16a formed at the end of the flange of the casing 4 is determined by the thickness t of the plate 5.
The inner surface of the end of the folding wall 16a that protrudes from the plate 5 is connected to the convex portion 17 on the outer surface of the generator.
Since the pump body is fitted with a spigot on the outer circumferential surface 17b of the pump body, the positioning of the pump body with respect to the generator casing can be made constant.

Compared to the conventional structure in which the ridge 14 and the recess 15 are fitted with a pilot through the plate 5, and the folded wall 16a and the plate 5 are fitted with a pilot at two places, the plate 5 and the convex part 17 are Since the vacuum pump 1 is connected to the generator 2 by direct spigot fitting between the It is also possible to loosen the dimensional accuracy.

(Example) In the automotive vacuum pump according to the present invention,
Flanges 16, 16 as shown in FIG. 4 are formed on the main body 4 of the casing 6, with each folding wall 16a facing the plate 5 side. Conventionally, the height h of the folded wall 16a of this flange was smaller than the thickness t of the plate 5 (h<
t), whereas in the present invention, as shown in FIG. 5, the height H of each folding wall 16a is made larger than the thickness t of the plate 5 (H>t). The outer surface of the plate 5 is formed by folding the plate 5 into this vertical wall 1.
It is processed so that it can be fitted with a pilot on the inside of 6a and 16a. As shown in FIG. 6, the casing 6 in which the height H of each folding wall 16a is larger than the thickness t of the plate 5 has a convex shape formed on the outer surface of the casing of the generator 2 on the outer surface of the plate 5. Part 17
At the same time, the inner surface of the folded wall 16a of the main body 4 is brought into contact with the outer peripheral surface 17b of the convex portion 17.
This main body 4 is positioned with respect to the casing of the generator 2 by fitting it with a spigot. Therefore, the inner surface of the folding wall 16a and the outer circumferential surface 17b of the convex portion 17, which contact each other, are finished with accurate dimensions. The other configurations are the same as those of the conventional automotive vacuum pump described above, and therefore redundant explanation will be omitted.

(Effects of the invention) (1) In the automotive vacuum pump of the invention, the main body 4 of the casing, which needs to be accurately positioned with respect to the casing of the generator 2, can be directly connected to the generator 2 without using the plate 5. Since positioning is performed by fitting the spigot into the casing, only one part for the vacuum pump and one for the generator are required to finish the dimensions accurately.Furthermore, manufacturing errors are not overlapped, resulting in higher processing accuracy than before. requires less rigor.

(2) Furthermore, since the plate 5 does not require strict dimensional accuracy for spigot fitting as in the past, it can be manufactured by press working, which could not be done in the case of the conventional structure.

(3) In addition to the fact that only one precision finishing part is required as described above, the effect of reducing the manufacturing cost of the automobile vacuum pump is extremely large.

[Brief explanation of the drawing]

Fig. 1 is a side view showing an automobile vacuum pump constructed by combining with a generator according to a conventional structure, Fig. 2 is a sectional view taken along the line A-A in Fig. 1, and Fig. 3 is a second drawing showing the conventional structure. Figure 4 is a view of the main body of the vacuum pump casing seen from the right side of Figure 3, Figures 5 and 6 show examples of the present invention, and Figure 5 shows the vacuum FIG. 6 is a vertical side view showing only the pump, and FIG. 6 is a vertical side view showing the pump combined with a generator. 1: Vacuum pump, 2: Generator, 3: Pulley,
4: Main body, 5: Plate, 6: Casing, 7:
groove, 8: vane, 9: rotor, 10: shaft, 11:
Intake port, 12: Discharge port, 13: Oil supply port, 14: Ridge, 15: Recess, 16: Flange, 16a: Vertical wall, 17: Convex portion, 17a: Outer surface, 17b: Outer peripheral surface, 18: Circular hole .

Claims (1)

[Scope of utility model registration request] In a vacuum pump for an automobile, the rotor 9 is driven by a shaft 10 that is coupled to the outer surface of the casing of a generator 2 driven by the engine of the automobile, and that is integrated with the shaft of the rotor of the generator 2. A pump casing 6 is composed of a cylindrical main body 4 and a plate 5 having a circular hole 18 through which the shaft 10 is inserted and closing the opening of the main body 4. 16, and the height H of a folded wall 16a formed by bending toward the plate 5 side at the end of this flange is made larger than the thickness t of the plate 5.
A vacuum pump for an automobile, characterized in that the main body 4 is coupled to the casing of the generator by fitting the inner surface of the main body 4 to the outer circumferential surface 17b of a convex portion 17 formed on the outer surface of the casing of the generator.