JPH07127476A - Speed increasing mechanism and supercharger - Google Patents

Abstract

PURPOSE:To mainly reduce weight and form a device in a compact manner by a method wherein two gears are respectively engaged with the internal tooth gear and the external tooth gear of an input gear to form a speed increasing mechanism and the speed increasing mechanism is combined with a volume type air compressor to form a supercharger. CONSTITUTION:A supercharger 21 comprises a speed increasing mechanism 23 and a screw type air compressor 25 being a volume type of one kind. Namely, the speed increasing mechanism 23 is formed so that internal and external tooth gears 49 and 51 are formed on an input gear 27 coupled to an input shaft 39 and respectively geared with two gears 29 and 31 having the relatively low number of teeth. Meanwhile, the air compressor 25 comprises protrusion-shaped and recess-shaped rotors 33 and 35 formed in a screw-form shape. The internal tooth gear 49 and the gear 29 and the external tooth gear 51 and the gear 31 are set to the number of teeth responding engagement between the two rotors 33 and 35 to form a timing gear set 53. This constitution causes synchronous rotation of the rotors 33 and 35 in a reverse direction to each other to feed intake air with a pressure.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a speed increasing mechanism and a supercharger using the speed increasing mechanism.

[0002]

2. Description of the Related Art Japanese Unexamined Utility Model Publication No. 4-42284 discloses a mechanical drive type supercharger 201 (supercharger) as shown in FIG. This is an air compressor 203 that pressurizes intake air and supplies it to the engine, and a gear mechanism 20 that transmits the driving force of the engine to the air compressor 203.
5 and. The air compressor 203 is a pair of rotors 207 that rotate while meshing with each other to pressurize intake air,
209 is a positive displacement type, and the gear mechanism 205 is composed of large and small gears 211 and 213, and a speed increasing gear set 215 that increases the driving force of the engine and a rotor 207 and 209 by the increased driving force. Synchronous gear 21 for synchronous rotation
7, 219 (timing gear).

[0003]

Although it is desirable to make vehicle-mounted equipment such as a supercharger as light and compact as possible, the gear mechanism 205 has four gears 211, as described above.
In addition to being composed of 213, 217 and 219, the speed increasing gear set 215 and the synchronous gears 217 and 219 are arranged in two rows in the axial direction, so that they are heavy and large. Also, the synchronous gear 2
17, 219 must be directly meshed and therefore cannot be smaller than the size determined by the axial distance between the rotors 207, 209.

Therefore, an object of the present invention is to provide a lightweight and compact speed increasing mechanism and a supercharger using this speed increasing mechanism.

[0005]

The speed increasing mechanism of the first invention is
An input gear that has an internal gear and an external gear and is driven to rotate by receiving a driving force, and a first gear and a second gear that respectively mesh with the internal gear and the external gear to accelerate the rotation. It is characterized by having.

Further, the second invention supercharger has an internal gear and an external gear and has an input gear which is rotationally driven by the engine, and an internal gear and an external gear which are individually meshed with each other to accelerate rotation. A speed increasing mechanism having a first gear and a second gear,
A pair of rotors are respectively connected to the first and second gears and synchronously driven to rotate, and a positive displacement air compressor for pressurizing engine intake air is provided.

[0007]

In the speed increasing mechanism, the internal gear and the external gear are formed in the input gear, and the first gear and the second gear are meshed with these gears, respectively. The number of gears has been reduced to three, and the gears are arranged in a row, making it lightweight and compact.

The supercharger is the first speed increasing mechanism.
The first and second gears are connected to the rotors of the positive displacement air compressor, respectively, and the first and second gears are used as timing gears to drive the rotors to rotate synchronously. In this speed increasing mechanism, it is not necessary to directly mesh the first and second gears,
These gears can have a small diameter, and each gear can be arranged freely to some extent according to the axial distance of the rotor.

[0009]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS An embodiment of the speed increasing mechanism of the first invention will be described with reference to FIG.

The speed increasing mechanism 1 includes an input gear 3 and first and second gears 5 and 7. The input gear 3 is provided with an internal gear 9 and an external gear 11, the first gear 5 meshes with the internal gear 9, and the second gear 7 meshes with the external gear 11. The input gear 3 is rotationally driven by receiving a driving force, and this rotation is speeded up via the gears 5 and 7, respectively, so that two sets of speed-up functions are formed. At this time, the gears 9 and 5 and the gear 1
If the speed increasing ratios of 1 and 7 are set to a required ratio, a timing gear set having a speed increasing function can be constructed.

This speed increasing mechanism 1 is composed of three gears 3, 5 and 7, which is one less than that of the conventional example, and since the gears 5 and 7 do not need to be directly meshed with each other, the diameter can be reduced.
It is lightweight. Further, since the gears 3, 5, 7 are arranged in a line, they are compact.

The speed increasing mechanism 1 has a center 13 of the gear 5.
Shows an example in which offset is arranged outside the straight line 19 connecting the centers 15 and 17 of the gears 3 and 7.

Next, an embodiment of the supercharger of the second invention will be described with reference to FIGS. 2 and 3. FIG. 2 shows this supercharger 21. It should be noted that members and the like without reference numerals are not shown.

As shown in FIG. 2, the supercharger 21 is provided with a speed increasing mechanism 23 and a screw type air compressor 25 which is a type of positive displacement type.

The speed increasing mechanism 23 includes an input gear 27 and first and second gears 29 and 31, and the air compressor 25 includes a screw-shaped convex rotor 33 and a concave rotor 35. ing.

The input gear 27 is connected to an input shaft 39 supported by a bearing 37, and is rotationally driven by the driving force of the engine input from the crankshaft side via the input shaft 39. Also, the shafts 41, 4 of the rotors 33, 35 are
3 are respectively supported by bearings 45 and 47, the gear 29 is connected to the shaft 41 of the rotor 33, and the gear 31 is connected to the shaft 43 of the rotor 35.

As shown in FIG. 2, the input gear 27 is formed with an internal gear 49 and an external gear 51. The gear 29 meshes with the internal gear 49 and the gear 31 meshes with the external gear 51. ing. The number of teeth of the gear 29 is smaller than that of the gear 49, and the number of teeth of the gear 31 is smaller than that of the gear 51 to configure the speed increasing mechanism 23. The driving force of the engine is increased to rotationally drive the air compressor 25.

Internal gear 49, number of teeth 29, and external gear 51
The gear 31 has a number of teeth corresponding to the meshing ratio of the rotors 33 and 35, respectively, and constitutes a timing gear set 53, and the rotors 33 and 35 are synchronously rotated in opposite directions as indicated by arrows 55 and 57. When the rotors 33, 35 are rotationally driven in this manner, the air compressor 25 draws intake air from the rotors 33, 35.
It is pumped in the axial direction between and supplied to the engine.

Thus, the supercharger 21 is constructed.

The speed increasing mechanism 23 is composed of three gears 27, 29, 31 which are smaller than the conventional one by one, and these gears are arranged in a row, so that they are lightweight and compact. In addition to this, since the gears 29 and 31 do not directly mesh with each other, when the axial distances 1 of the rotors 33 and 35 are the same, the gears 29 and 31 have smaller diameters, and the supercharger 21 can be made lighter and more compact. .

The center 59 of the gear 29 is on the line 65 connecting the center 61 of the input gear 27 and the center 63 of the gear 31,
The gear 29 meshes with the internal gear 49 on the gear 31 side.
However, depending on the inter-axis distance l, the gear 29 may be engaged with the internal gear 49 at the position indicated by the arrow 67, or in FIG.
The center of each gear may be offset on a non-straight line as in the example. Thus, the supercharger 21 has a high degree of freedom in the arrangement of the gears 27, 29, 31.

The air compressor used in the second invention is, for example, a roots type in addition to the screw type.

[0023]

According to the speed increasing mechanism of the first invention, the three gears are arranged in a row by individually meshing the first and second gears with the internal gear and the external gear provided on the input gear. With
Since the first and second gears do not have to be directly meshed with each other and can have a small diameter, they are lightweight and compact. or,
Since it has two sets of speed increasing functions, it can be used as a timing gear set having a speed increasing function and has a wide range of application.

In the supercharger of the second aspect of the invention, the driving force of the engine is increased to rotate the rotor synchronously through the speed increasing mechanism of the first aspect of the invention which is constructed as a timing gear set having a speed increasing function. Therefore, it is lightweight and compact, and the degree of freedom in arranging the gears is high according to the axial distance of the rotor.

[Brief description of drawings]

FIG. 1 is a schematic view showing an embodiment of the first invention.

FIG. 2 is a schematic view showing an embodiment of the second invention.

FIG. 3 is a front view of a speed increasing mechanism used in a second invention.

FIG. 4 is a sectional view of a conventional example.

[Explanation of symbols]

 1,23 Speed-up mechanism 3,27 Input gear 5,29 First gear 7,31 Second gear 9,49 Internal gear 11,51 External gear 21 Supercharger 25 Air compressor 33,35 Rotor

Claims (2)

[Claims] 1. An input gear having an internal gear and an external gear, which is rotationally driven by receiving a driving force, and first and second gears which are individually meshed with the internal gear and the external gear to accelerate rotation. A speed-up mechanism including two gears. 2. An input gear, which has an internal gear and an external gear and is driven to rotate by an engine, and first and second gears that individually mesh with the internal gear and the external gear to accelerate rotation. A supercharger comprising: a speed increasing mechanism having a gear; and a positive displacement air compressor in which a pair of rotors are separately connected to the first and second gears and driven to rotate synchronously to pressurize engine intake air. .