JPH01310122A - Mechanical supercharger - Google Patents

Abstract

PURPOSE:To shorten the total length to a supercharger in comparison with a device which comprises a large gear and a rotor shaft bearing arranged in parallel to each other by providing such a constitution that the large gear for increasing speed is fittedly supported rotatably on the outer circumference of the bearing of a rotor shaft acting as a driven shaft during increasing speed. CONSTITUTION:In order to rotate a rotor shaft 3a, a multiplate type crack 12 is connected to a large gear 14 which has a larger diameter than that of a small gear 7, has more gear teeth than it, and meshes with the small gear 7. In addition, in order to support the large gear 14, the bearing part 6b of a housing 6 for supporting a rotor shaft 3b is formed cylindrically, and a ball bearing 15 is fitted thereon, while the large gear 14 is fittedly supported on the outside of the ball bearing 15, rotatably in relation to the housing 6. Further, the large gear 14 acting as a speed increasing device is engaged with the bearing 6b so that the bearing 6 forms the shaft of the large gear 14, instead of being arranged in parallel to the bearing 6b of the rotor shaft 3b. Therefore, the total length of a supercharger is thus shortened by a partial length of the large gear 14 fitted in the bearing 6b.

Description

[Detailed Description of the Invention] [Industrial Application Field] The present invention includes a rotary drive unit rotated by external power, and a speed increasing mechanism that increases the speed of rotation of the drive unit and transmits it to a rotor shaft. It relates to a mechanical supercharger for an internal combustion engine.

[Conventional technology and issues]

A mechanical supercharger equipped with a speed increasing mechanism is, for example,
It is described in No. 61940. In this mechanical supercharger, for example, as shown in FIG. 3, a drive shaft 20 serving as a rotational drive unit rotates at an increased speed a rotor shaft 24 that supports a drive rotor 23 via a large gear 21 and a small gear 22. On the other hand, the rotor shaft 26 supporting the driven rotor 25 is driven by the rotor shaft 24 via gears 27 and 28 having the same diameter and the same number of teeth. However, as shown in the figure, this speed increasing mechanism increases the total length of the supercharger (the lateral dimension in the figure), resulting in a problem of increasing the size of the supercharger. Although not shown, even in mechanical superchargers equipped with a speed increasing mechanism such as a planetary gear, the drive side rotor shaft must be extended to provide a planetary gear, and the overall length of the supercharger tends to increase. Remarkable.

The present invention has been made in view of the current situation, and an object of the present invention is to provide a compact supercharger without increasing its overall length when the supercharger is equipped with a speed increasing mechanism.

[Means to solve the problem]

In order to solve the above problems, the present invention includes a pair of rotors that engage and rotate, and a small gear that is fitted and fixed to a rotor shaft that supports one of the rotors, and a small gear that rotates the rotor. In a mechanical supercharger equipped with a speed increasing mechanism including a large gear connected to a rotational drive unit and meshing with the small gear, the rotor shaft supports the other of the pair of rotors. A mechanical supercharger is provided, characterized in that the bearing is formed in a cylindrical shape, and the large gear is rotatably fitted and supported on the outer periphery of the bearing.

[For production]

The shaft that supports the large speed-increasing gear is not placed in parallel with the rotor shaft bearing, and the rotor shaft bearing is formed into a cylindrical shape.
By also serving as the shaft of the large gear, the overall length of the mechanical supercharger can be shortened by the amount that the large gear is fitted to the bearing.

〔Example〕

Embodiments of the present invention will be described below by taking as an example a mechanical supercharger equipped with a speed increasing mechanism capable of speed switching over two stages.

In FIGS. 1 and 2, 10 indicates a mechanical supercharger,
This supercharger IO has a pair of rotors 2a.

It is composed of a Roots pump with 2b.

It is known that the rotors 2a and 2b of the mechanical supercharger 10 have bilobal cross sections as shown in FIG. 2, and that they perform a pumping action by rotating in opposite directions in synchronization with each other. That's right.

Each rotor 2a, 2b has a rotor shaft 3a,
3b, rotor shirt) 3a, 3
Connecting gears 4a and 4b having the same diameter and the same number of teeth are fixed to the right end of the rotors 2a and 2b and mesh with each other in order to rotate both rotors 2a and 2b synchronously. Rotor shaft 3a, 3
b is a ball bearing 5a.

5b, is rotatably supported by the housing 6 by bearing parts 5a, 5b, etc. of the housing 6, and the rotor shaft 3a extends further from the housing bearing part 6a, and the speed increasing mechanism of the present invention is installed at the left end thereof. The constituting small gear (sub gear) 7 is fixed.

Hereinafter, the speed increasing mechanism provided in the supercharger of the present invention will be explained. On the left side of the rotor shaft 3b, a pulley 8 is provided which is coaxial with the rotor shaft 3b and serves as a 100 rotation drive unit for the supercharger. is rotated through. A drive rotor 9 is provided inside the pulley 8 and rotates integrally with the pulley 8. A rotor shaft 3 is provided inside the drive rotor 9 in the radial direction.
A one-way clutch 11 is provided for transmitting the signal to b. This one-way clutch 11 applies torque only to one rotation of the drive rotor 9 to the rotor shaft 3b.
It has the function of transmitting information to the direction of rotation and idling in the opposite rotation direction.
This is a so-called ratchet type clutch, and is used to transmit the rotation of the pulley 8 to the rotor shaft 3b without increasing the speed.

By the way, a multi-disc clutch 12 is provided outside the one-way clutch 11 to increase the rotation speed of the drive rotor 9 and transmit it to the rotor shaft 3a. According to this embodiment, the clutch 12 has, for example, a plurality of annular plates that are actuated by magnetic force, and an electromagnetic coil 13 that generates the magnetic force for actuating the clutch 12 is arranged near the annular plates.

The multi-plate clutch 12 is connected to a large gear (free gear) 14 in order to rotate the rotor shirt 3a. The large gear 14 is a gear having a larger diameter and a larger number of teeth than the small gear 7 described above, and is in a meshing relationship with the small gear 7.

In order to support the large gear 14, the bearing part 6b of the housing 6 that supports the rotor shirt 3b is formed into a cylindrical shape, and a ball bearing 15 is fitted into this part. 14 is rotatably fitted and supported by the housing 6. That is, according to the present invention, the large gear 14 as a speed increasing mechanism is not arranged in parallel to the bearing 6b of the rotor shirt 3b, but as if the bearing 6b were the large gear I.
It is fitted into the bearing 6b so as to form a shaft of No. 4. Therefore, the overall length of the supercharger is reduced by the amount that the large gear 14 is fitted into the bearing 6b. In this embodiment, in addition to the method of attaching the large gear 14 described above, the end surface of the small gear 7 that meshes with the large gear 14 is formed into a concave shape, so that the width dimension of the bearing 6a of the rotor shirt 3a can be made sufficiently large. After ensuring this, an increase in the overall length of the supercharger due to the width dimension of the small gear 7 is suppressed.

Next, the operation of the mechanical supercharger 10 of this embodiment configured as described above will be explained.

When the supercharger 10 does not perform speed-up operation, the electromagnetic coil 13 is de-energized, and the rotational force transmitted to the pulley 8 by the crankshaft is transmitted to the drive rotor 9, and then transmitted to the rotor shaft 3b via the one-way clutch 11. be done.

This rotational driving force is then transmitted to the rotor shaft 3a via the connecting gears 4b and 4a (see the solid arrow in FIG. 1). Therefore, in this case, the rotor shaft 3b is the driving shaft, and the rotor shaft 3a is the driven shaft.
The one-way clutch 11 functions as a clutch. On the other hand, in the case of speed-up operation, the electromagnetic coil 13 is energized, the multi-disc clutch 12 is operated, and the drive rotor 9 and the large gear 14 are brought into multi-disc contact due to magnetic force, and the driving force is connected.

Therefore, the rotational force from pulley 8 is transferred to drive rotor 9, large gear 1
4 to the small gear 7, and the rotor shirt 3a rotates (see the dotted line arrow in Figure 2). The rotation of the rotor shirt 3a is transmitted to the rotor shaft 3b via the connecting gears 4a and 4b. Therefore, in this case, the rotor shaft 3a is the driving shaft, and the rotor shaft 3b is the driven shaft. ) 3b (not shown) overtakes the interlocking member (not shown) of the drive rotor 9, resulting in a so-called overrun state, and the clutch does not function as a power transmitter.

FIG. 3 shows another embodiment different from the embodiment shown in FIG. In this embodiment, the same elements as in the embodiment of FIG. 1 are given the same numbers.

In the previous embodiment, the connecting gears 4a, 4b for synchronously rotating the rotors 2a, 2b are the rotors 2a, 2b.
In contrast, in this embodiment, the connecting gears 4a and 4b are provided adjacent to the small gear 7 and the large gear 14, respectively, on the opposite side of the small gear 7 and the large gear 14 with the rotor shaft 3a and the large gear 14 in between. 3b by a key or a spline. This consists of small gear 7, large gear 14, and connecting gear 4.
a.

4b, the twist angle applied to the rotor shafts 3a and 3b can be minimized, and the rotor shirt) 3a
, 3b itself, and is intended to reduce the diameter of these shafts. In addition, in this embodiment, these gears 7.1, which are driving force transmission means,
By centrally providing 2.4a and 4b on one side of the supercharger 10a, an oil level gauge and a magnet for collecting metal powder, which conventionally had to be provided on both sides of the supercharger, can be installed. Auxiliary devices such as plugs (both not shown) need only be installed on one side, reducing costs and making the system more compact.In addition, by simplifying the lubricating thread, it is easy to reduce lubricant consumption and reduce gear noise. This will be effective for maintenance purposes. Naturally, also in this embodiment, the large gear 14 is rotatably fitted and supported by the cylindrical bearing 6c constituting the bearing of the rotor shaft 3b via the ball bearing 15.
The shaft itself also serves as the shaft of the large gear 14. Therefore, there is virtually no clearance between the small gear 7 and the large gear and the connecting gears 4a and 4b, and the rotor shafts 3a and 3 located between them are
The twist angle of b can be made small.

The embodiments of the present invention have been described above by taking as an example a supercharger equipped with a speed increase mechanism capable of speed switching over two stages, but the present invention naturally also applies to a clutch as shown in FIG. It is also applicable to a supercharger equipped with a general speed increasing mechanism that simply increases the rotation speed of the drive shaft 20 serving as a rotational drive unit and drives the rotor shaft 24. too,
The large gear 21 may be arranged around the bearing 29.

〔effect〕

As described above, according to the present invention, the large gear for increasing speed is rotatably fitted and supported on the outer periphery of the bearing of the rotor shaft, which becomes the driven shaft during speed increasing. The overall length of the supercharger can be shortened compared to one in which shaft bearings are arranged side by side, and a supercharger that is generally compact can be provided.

[Brief explanation of the drawing]

Fig. 1 is a sectional view of the mechanical supercharger of the present invention; Fig. 2 is a sectional view of the mechanical supercharger of the present invention;
Figure 3 is a cross-sectional view of a supercharger as another embodiment different from Figure 1; Figure 4 is a schematic cross-sectional view of a conventional turbocharger with a speed increasing mechanism. . 2a, 2b...Rotor, 3a, 3b...Rotor shaft, 4a, 4b...Connection gear, 6a, 6b, 6c...Bearing (part), 7...Small gear, lO... Mechanical supercharger, 14... large gear.

Claims (1)

[Claims] 1. It has a pair of rotors that engage and rotate, and a small gear that is fitted and fixed to a rotor shaft that supports one of the rotors, and a rotation for rotating the rotor. In a mechanical supercharger equipped with a speed increasing mechanism configured by a large gear connected to a drive part and meshing with the small gear, the bearing of the rotor shaft supporting the other of the pair of rotors is cylindrical. A mechanical supercharger characterized in that the large gear is rotatably fitted and supported on the outer periphery of the bearing.