JPH07243331A - Mechanical supercharger - Google Patents

Abstract

PURPOSE:To enhance discharge efficiency by arranging a pair of rotors having claws and rotating in an opposite direction each other, specifying the width in the circumferential direction of each claw to the width of an air discharge port, forming a plurality of compressed air outflow ports in a guide wall covering the air discharge port, and mounting a reed valve to each outflow port. CONSTITUTION:A mechanical supercharger 1 has a pair of cylindrical rotors 3, 4 which rotate in an opposite direction each other around rotating axial lines which are positioned in parallel each other in a housing 2. The rotors 3, 4 have claws 5, 6 and recesses 7, 8 for inserting the claws 5, 6 are formed in the outer circumference of each rotor. The circumferential width W of each of claws 5, 6 is formed so as to become half or less the width X of an air discharge port 10. The air discharge port 10 is covered with a guide wall 13 having a pair of cylindrical inner circumferential surfaces 11, 12, a plurality of compressed air outflow ports 14 are formed on each of the cylindrical inner circumferential surfaces 11, 12 of the guide wall 13, and a valve seat member 15 and a reed valve 16 capable of being seated to the valve seat member 15 are arranged in each of the outflow ports 14.

Description

Detailed Description of the Invention

[0001]

FIELD OF THE INVENTION The present invention relates to a mechanical supercharger.

[0002]

2. Description of the Related Art A pair of rotors that rotate at the same speed in opposite directions at a slight gap from each other about rotation axes that are parallel to each other are arranged in a housing, and each rotor extends along a cylindrical inner peripheral surface of the housing. A plurality of rotor blades that move in parallel with each other, form an air suction port on the housing on one side with respect to the plane containing the rotation axes of both rotors, and air on the housing on the other side with respect to this plane. A mechanical supercharger is known in which a discharge port is formed, and a reed valve that allows only the discharge of air is provided in the air discharge port (Japanese Patent Laid-Open No. 6-58242).
0-45719 gazette). In such a mechanical supercharger, as the rotors rotate in mutually opposite directions, the volume of the compression space formed between the rotor blades of one rotor and the rotor blades of the other rotor is gradually reduced, and within the compression space. When the pressure of the compressed air rises to the pressure on the downstream side of the reed valve, the compressed air in the compression space is discharged from the air discharge port via the reed valve.

[0003]

By the way, in such a mechanical supercharger, when the compressed air in the compression space is being discharged, the compression space becomes the next compression space via the air discharge port. When it is made to communicate with the space between them, the compressed air in the compression space flows back to the space of the rotor blades, which should be the compression space next time, and thus the efficiency is reduced. In order to prevent such backflow of compressed air, it is necessary to separate the air discharge port and the space to be the compression space next by the rotor blades until the discharge action of the compressed air is completed. The circumferential width of the outer peripheral surface of the rotor blade is considerably long.

However, if the circumferential width of the outer peripheral surface of each rotor blade is increased, the size of the entire rotor blade inevitably increases, and if the size of the entire rotor blade increases, the volume that can be used as a compression space decreases. It causes a problem that the efficiency is lowered.

[0005]

In order to solve the above-mentioned problems, according to the present invention, a pair of cylindrical members which rotate at the same speed in opposite directions with a slight gap between them about rotation axes which are parallel to each other. The rotors are arranged in the housing, and each of the rotors has a claw portion extending radially from the cylindrical outer peripheral surface of the rotor to the vicinity of the cylindrical inner peripheral surface of the housing. The claw portion has a concave portion into which the claw portion enters, and the claw portion has a cylindrical outer peripheral surface extending along the inner peripheral surface of the cylindrical housing with a slight gap from the inner peripheral surface of the corresponding cylindrical housing. In the mechanical supercharger in which the air suction port is formed on the housing on one side with respect to the plane including the rotation axis and the air discharge port is formed on the housing on the other side with respect to this plane, The peripheral width of the cylindrical outer peripheral surface of the part is less than half the width of the air outlet in the cross section perpendicular to the rotor's axis of rotation, and the air outlet has a slight gap between the cylindrical outer peripheral surfaces of the claws. And a plurality of slit-like compressed air outlets having a width narrower than the circumferential width of the cylindrical outer peripheral surface of the claw portion are formed on the guide wall. A reed valve that allows only the outflow of compressed air is attached to each compressed air outlet.

Further, according to the present invention, in order to solve the above problems, the guide wall is formed of a curved plate, and the reed valve is arranged on the outer peripheral surface of the curved plate. Further, according to the present invention, in order to solve the above-mentioned problem, when the claw portion of one rotor intrudes into the concave portion of the other rotor, compressed air is released to the outside from the internal space formed between them. The compressed air escape passage is formed between each claw portion and the rotor outer peripheral surface facing the claw portion.

[0007]

In the first aspect of the invention, when the pressure of the air between the claw portions of each rotor becomes equal to the pressure on the downstream side of the reed valve, this air is discharged from the compressed air outlet via the reed valve. The compressed air outlet is then closed by the cylindrical outer surface of the pawl. In the second aspect of the invention, since the compressed air outlet is formed on the curved plate, the volume of the compressed air outlet is small, and therefore compressed air is efficiently discharged through the reed valve.

In the third aspect of the invention, the air in the internal space formed between the claw portion of one rotor and the concave portion of the other rotor is released to the outside without being subjected to excessive compression.

[0009]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS Referring to FIG. 1, a mechanical supercharger 1 includes a pair of cylindrical rotors which rotate in the housing 2 in the opposite directions S at the same speed with a slight gap around the rotation axes parallel to each other. 3 and 4 are provided. Each rotor 3, 4
Are provided with rotor blades, that is, claw portions 5 and 6 extending radially from the cylindrical outer peripheral surfaces 3a and 4a of the rotors 3 and 4 to the vicinity of the cylindrical housing inner peripheral surface 1a. Further, recesses 7 and 8 into which the claw portions 5 and 6 of the other rotor 3 and 4 enter are formed on the cylindrical outer peripheral surfaces 3a and 4a of the rotors 3 and 4, respectively. An air suction port 9 is formed on the housing 1 on one side of the plane including the rotation axes of the rotors 3 and 4, and an air discharge port 10 is formed on the housing 1 on the other side of this plane. It is formed. The air discharge port 10 has a slit shape extending in the axial direction of each rotor 3, 4.

The claws 5, 6 have a substantially uniform thickness over their entire length, and the outer peripheral surfaces 5a, 6a of the claws 5, 6 are separated from the inner peripheral surface 1a of the housing by a slight gap. It has a cylindrical shape extending along the inner peripheral surface 1a. As can be seen from FIG. 1, the circumferential width W of the outer peripheral surfaces 5a, 6a of the claws 5, 6 is W.
Is formed to be half or less of the width X of the air discharge port 10 in a cross section perpendicular to the rotation axes of the rotors 3 and 4. The air discharge port 10 is covered with a guide wall 13 having a pair of cylindrical inner peripheral surfaces 11 and 12. Guide wall 13
The respective cylindrical inner peripheral surfaces 11 and 12 extend along the same cylindrical surface as the corresponding housing inner peripheral surface 1a. Therefore, the cylindrical outer peripheral surfaces 5a and 6a of the respective claw portions 5 and 6 correspond to the guide wall 13. It moves along the cylindrical inner peripheral surfaces 11 and 12 with a slight gap from the cylindrical inner peripheral surfaces 11 and 12.

Each cylindrical inner peripheral surface 11, 12 of the guide wall 13
A plurality of, in the embodiment shown in FIG. 1, six compressed air outlets 14 are formed on the top. As can be seen from FIG. 1, the circumferential width S of each compressed air outlet 14 is formed smaller than the circumferential width W of the cylindrical outer peripheral surfaces 5a, 6a of the claws 5, 6. The guide wall 13 is provided with a plurality of reed valve seat members 15 that are curved and extend substantially parallel to each other, and a reed valve 16 provided for each reed valve seat member 15. The inner end of each reed valve 16 is supported by the guide wall 13 in the vicinity of the cylindrical inner peripheral surfaces 11 and 12 of the guide wall 13, and the outer end of each reed valve 16 is usually the corresponding reed valve seat member. The compressed air outlet 14 corresponding to the compressed air outlet 14 is closed by being seated on the tip of the valve 15.

FIG. 2A shows the direction of rotation S from the claw portions 5 and 6.
The compressed space 17 extending in the direction shown in the figure is in communication with the air suction port 9, and at this time, the compression action of the air in the compressed space 17 is not performed. Next, when the rotors 3 and 4 are rotated in the direction of arrow S and the cylindrical outer peripheral surface 5a of the claw portion 5 of the rotor 3 faces the housing inner peripheral surface 1a, the compression space 17 is isolated from the air suction port 9. After that, when the rotors 3 and 4 rotate further, the volume of the compression space 17 becomes smaller than that in FIG.
As can be seen from (B), the air in the compression space 17 is compressed to gradually decrease, and the space 18 other than the compression space 17 is compressed.
Air is sucked in through the air suction port 9. Next, the air pressure in the compression space 17 is changed to the air discharge port 10 downstream of the reed valve 16.
When it becomes equal to the internal air pressure, the air in the compression space 17 is discharged from each compressed air outlet 14 via the reed valve 16. The action of discharging the air from the compressed air outlet 14 is started, for example, from the state shown in FIG. 2 (B) and continued until the state shown in FIG.

In the state shown in FIG. 1, the fourth compressed air outlet 14 from the top in FIG.
Therefore, the compressed air in the compression space 17 is discharged from the fourth compressed air outlet 14 from the top in FIG. 1 through the corresponding reed valve 16. On the other hand, in FIG. 1, the first and second compressed air outlets 14 from the top and the first and second compressed air outlets 14 from the bottom are shown.
Communicate with a space 18 other than the compression space 17, and since the air pressure in this space 18 is lower than the air pressure in the air discharge port 10 downstream of the reed valve 16, the reed valves 16 of these compressed air outlets 14 are closed. is doing. Further, in FIG. 1, the third compressed air outlet 14 from the top is closed by the cylindrical outer peripheral surface 5a of the claw portion 5, so that the compressed air outlet 14
The reed valve 16 of is also closed.

By the way, in FIG. 1, the width W in the circumferential direction of the cylindrical outer peripheral surfaces 5a and 6a of the claws 5 and 6 is assumed to be the compressed air outlet 1.
If the width is smaller than the circumferential width S of 4, the compression space 17 communicates with the space 18 other than the compression space 17 via the compressed air outlet 14, and thus the compressed air in the compression space 17 is transferred to the space 18. I run away. Therefore, the circumferential width W of the cylindrical outer peripheral surfaces 5a, 6a of the claw portions 5, 6 must be made wider than the circumferential width S of the compressed air outlet 14. In this case, the smaller the circumferential width S of the compressed air outlet 14 is, the smaller the circumferential width W of the cylindrical outer peripheral surfaces 5a, 6a of the claw portions 5, 6 can be made, and therefore, it is shown in FIG. When the air outlet 10 is divided into a large number of compressed air outlets 14 as described above, the circumferential width W of the cylindrical outer peripheral surfaces 5a and 6a of the claws 5 and 6 can be considerably reduced.

By the way, the cylindrical outer peripheral surface 5 of each claw portion 5, 6
The fact that the circumferential width W of a and 6a can be reduced means that the overall dimensions of the claws 5 and 6 can be reduced.
The fact that the overall dimensions of the claws 5, 6 can be reduced means that the volume of the compression space 17 at the beginning of compression can be increased. If the volume of the compression space 17 at the beginning of the compression can be increased, the efficiency is improved accordingly, and thus the efficiency of the mechanical supercharger 1 can be improved in the present invention.

FIG. 3 shows the rotor 3 from the state shown in FIG.
4 is shown rotated. In the state shown in FIG. 3, the action of discharging the compressed air has already been completed, and the claw portion 6 of the rotor 4 has entered the recess 7 of the rotor 3. At this time, an internal space 19 whose volume gradually decreases is formed between the claw portion 6 and the concave portion 7. When the internal space 19 becomes a completely closed space, the air in the internal space 19 is excessively compressed. As a result, the amount of lost work increases, and the efficiency of the mechanical supercharger 1 decreases. Therefore, in the embodiment according to the present invention, the compressed air escape passage 20 for allowing the air in the internal space 19 to escape to the outside is formed between the claw portion 6 and the outer peripheral surface of the concave portion 7. Further, in the embodiment according to the present invention, another compressed air escape passage 21 is formed between the ends of the claw portion 6 and the concave portion 7.

Such compressed air escape passages 20 and 21 can be easily formed by appropriately determining the shapes of the claw portion 6 and the concave portion 7. A compressed air escape passage similar to the compressed air escape passages 20 and 21 is formed between the outer peripheral surfaces of the claw portion 5 and the concave portion 8. FIG. 4 shows another embodiment. In this embodiment, the guide wall 30 covering the air discharge port 10 is formed of a curved plate. Also in this embodiment, the respective cylindrical inner peripheral surfaces 31, 32 of the guide wall 30 extend along the same cylindrical surface as the corresponding housing inner peripheral surface 1a, and accordingly, the cylindrical outer peripheral surfaces 5a of the respective claw portions 5, 6 are formed. , 6
a moves along the cylindrical inner peripheral surfaces 31, 32 with a slight gap from the corresponding cylindrical inner peripheral surfaces 31, 32 of the guide wall 30.

Each cylindrical inner peripheral surface 31, 32 of the guide wall 30
A plurality of, in the embodiment shown in FIG. 4, two compressed air outlets 33 are formed on the top. As can be seen from FIG. 4, the circumferential width S of each compressed air outlet 33 is formed smaller than the circumferential width W (FIG. 1) of the cylindrical outer peripheral surfaces 5a and 6a of the claws 5 and 6. Reed valves 34 are arranged on the outer peripheral surface of the guide wall 30 for the respective compressed air outlets 33, and one ends of these reed valves 34 are supported by a reed valve support member 35. Also in this embodiment, when the air pressure in the compression space 17 becomes equal to the pressure in the air discharge port 10 downstream of the reed valve 34, the compressed air in the compression space 17 becomes reed valve 3.
It is ejected into the air ejection port 10 via 4. Note that FIG.
Although the embodiment shown in FIG. 2 shows the case where two compressed air outlets 33 are formed, it goes without saying that more compressed air outlets 33 can be formed as shown in FIG.

[0019]

The efficiency of the mechanical supercharger can be improved.

[Brief description of drawings]

FIG. 1 is a side sectional view of a mechanical supercharger.

FIG. 2 is a diagram for explaining the operation of the supercharger.

FIG. 3 is a side sectional view of the mechanical supercharger immediately after the completion of the compressed air discharge operation.

FIG. 4 is a side sectional view showing another embodiment of the mechanical supercharger.

[Explanation of symbols]

 2 ... Housing 3, 4 ... Rotor 5, 6 ... Claw portion 7, 8 ... Recessed portion 9 ... Air suction port 10 ... Air discharge port 13, 30 ... Guide wall 14, 33 ... Compressed air outlet 16, 34 ... Reed valve

Claims (3)

[Claims] 1. A pair of cylindrical rotors, which rotate at the same speed in opposite directions with a slight gap between them about rotation axes that are parallel to each other, are arranged in a housing, and each rotor has a cylindrical outer peripheral surface. To the vicinity of the inner circumferential surface of the housing having a cylindrical shape, the claw portion extending in the radial direction is provided, and the claw portion of the other rotor is provided in the cylindrical outer circumferential surface of the rotor, and the claw portion has a corresponding cylindrical shape. It has a cylindrical outer circumferential surface that extends along the inner circumferential surface of the housing with a slight gap from the inner circumferential surface of the housing. In the mechanical supercharger in which the mouth is formed and the air outlet is formed on the housing on the other side of the plane, the circumferential width of the cylindrical outer peripheral surface of each claw is perpendicular to the rotation axis of the rotor. To The width of the air outlet is less than half the width of the formed air outlet, and the air outlet is covered with a guide wall having a cylindrical inner peripheral surface that moves with a slight gap between the cylindrical outer peripheral surfaces of the claws. A plurality of slit-shaped compressed air outlets with a width narrower than the circumferential width of the cylindrical outer peripheral surface of the claw portion are formed on the wall, and a reed valve that allows only the outflow of compressed air is attached to each compressed air outlet. Mechanical supercharger. 2. The guide wall comprises a curved plate,
The mechanical supercharger according to claim 1, wherein a reed valve is arranged on an outer peripheral surface of the curved plate. 3. A compressed air escape passage for escaping compressed air to the outside from an internal space formed between the claw portions of one rotor when the claw portions of the other rotor intrude into the recesses of the other rotor. The mechanical supercharger according to claim 1, wherein the mechanical supercharger is formed between the outer peripheral surfaces of the rotors facing each other.