JP2016008533A - air compressor - Google Patents

Abstract

PROBLEM TO BE SOLVED: To eliminate some disadvantages that a small-sized high output built-in type motor must be sufficiently cooled in order to assure performance of the motor or its safety due to the fact that a large amount of heat is generated at the motor and the motor is hardly cooled, and when a diameter of a housing for fixing a stator becomes larger than that of a crank case, the housing may become a location showing the largest diameter, so that it is necessary to make a thin wall as much as possible to make a light weight and eliminate some possibility that a poor rigidity occurs due to a thin wall housing to cause noise or irregular sound to occur and fatigue breakage of the housing may occur due to vibration of the motor.SOLUTION: A location for use in connecting a crank case with a housing for fixing a stator arranged at one end side of the crank case is provided with vent holes through which cooling air passes. In addition, there are provided between the vent holes ribs for reinforcing the housing and the fixture for fixing the stator to the housing.

Description

  The present invention relates to a compressor body structure of an air compressor.

  There is JP, 2004-124712, A (patent documents 1) as background art of the present invention. Patent Document 1 discloses a motor as a drive source, a compressor main body that generates compressed air by reciprocating a piston in a cylinder by rotational driving by a motor in a crankcase disposed adjacent to the motor, and a compressor main body. In the air compressor having a cooling fan that is driven to rotate by the motor on the opposite side of the motor, the crankcase has a protruding portion that protrudes outward from the motor in the radial direction, and the cooling fan is provided at the protruding portion. An air compressor is described in which a cooling air passage is formed through which the cooling air is passed and discharged along the outer peripheral surface of the motor.

JP 2004-124712 A

  In Patent Document 1, the outer diameter of the crankcase is made larger than the outer diameter of the motor and the cooling air passage is provided in the crankcase, but this is not considered in terms of size and weight reduction.

  In order to improve workability and reduce work load, portable air compressors mainly used at construction sites have been designed to be high pressure, small and light. The maximum pressure has been increased to 4MPa or more at present, and since the pressure has already reached the limit, it is necessary to further reduce the size and weight.

  In order to reduce the weight of the product, the compressor body, which accounts for the majority of the product mass, can be made smaller and faster, and the outer diameter of the connecting rod, cylinder, air valve, cylinder head, and crankcase can be reduced by downsizing the piston. On the other hand, the motor has a certain large diameter in order to secure torque and inertial force, and it is effective to suppress the mass by using a flat motor.

  Here, a built-in type motor is used for the portable air compressor, and a stator constituting the motor is generally fixed to a housing provided on one end side of the crankcase by using screws or the like. In addition, since a small and high-power motor generates a lot of heat and is difficult to cool, it must be sufficiently cooled to ensure the performance and safety of the motor.

In order to solve the above problems, for example, the configuration described in the claims is adopted. The present application includes a plurality of means for solving the above-mentioned problem. To give an example, an air compressor, which is a piston that reciprocates in a cylinder, a crankcase that houses a drive portion of the piston, A cooling fan that generates cooling air; a motor that drives the piston and the cooling fan;
A housing for fixing a stator constituting the motor is provided on one end side of the crankcase and integrally formed, and the housing has an outer diameter larger than the crankcase outer diameter, The connection surface connecting the outer peripheral surface of the case and the outer peripheral surface of the housing is provided with a vent hole through which the cooling air passes.

  According to the present invention, a compact and lightweight compressor body can be provided.

It is the front view and sectional drawing of the compressor main body of Example 1 which concern on this invention. It is the front view and sectional drawing of the compressor main body of Example 2 which concern on this invention. It is the front view and sectional drawing of the compressor main body of Example 3 which concern on this invention. It is the front view of the compressor main body of Example 4 which concerns on this invention, and the schematic diagram of a casting die. It is sectional drawing of the compressor main body of Example 5 which concerns on this invention.

  Hereinafter, embodiments of the present invention will be described with reference to the drawings.

  FIG. 1 is a front view and a cross-sectional view of a compressor body of an air compressor according to the present embodiment. In FIG. 1, (B) is a front view of a compressor main body, and sectional drawing in AA of FIG. 1 (B) is FIG. 1 (A).

  In FIG. 1A, flanges 2 and 3 are provided on the left and right sides of the crankcase 1, and cylinders 4 and 7, air valves 5 and 8, and cylinder heads 6 and 9 for forming a compression chamber are provided there. Is installed. A shaft 13 rotatably supported by bearings 11 and 12 is attached to the inside of the bearing box 10 fitted to the crankcase 1 and the opening side thereof. Connecting rods 16 and 17 having pistons 14 and 15 for moving up and down and sucking and compressing air are connected to eccentric members 18 and 19 via bearings 20 and 21. That is, the shaft 13, the connecting rods 16 and 17, the eccentric members 18 and 19, and the bearings 20 and 21, which are driving portions of the pistons 14 and 15, are accommodated in the crankcase 1. Further, a rotor 22 constituting a motor for rotating the shaft 13 is attached to one end side of the shaft 13.

  A housing 24 larger than the outer diameter of the crankcase 1 is formed integrally with the crankcase on the side opposite to the opening side of the crankcase 1 in which the bearing box 10 is fitted, and the stator 23 constituting the motor. Is fixed to the housing 24. Furthermore, a cooling fan 25 for cooling the stator 23 is attached to the end of the shaft 13, and the stator 23 is cooled when the cooling air 30 generated by the rotation of the shaft 13 strikes the stator 23.

  In FIG. 1 (B), the connection surface 28 that connects the outer peripheral surface 26 of the crankcase 1 and the outer peripheral surface 27 of the housing 24 is provided with a vent hole 29 for the cooling air 30 generated by the cooling fan 25.

  As a result, by making the diameter of the housing for fixing the stator that constitutes the motor larger than the diameter of the crankcase, it is possible to reduce the size and weight while ensuring the torque and inertial force of the motor. Since the stator which comprises a motor can be cooled efficiently, the compressor which can aim at ensuring safety | security can be provided.

  Although the present embodiment is a horizontally opposed two-cylinder compressor, the mechanism and structure of the compression unit are not limited. In the present embodiment, the cooling fan is applied to the stator in the axial flow fan, but the direction in which the cooling air flows may be reversed, or another fan such as a centrifugal fan may be used. The cooling fan may be provided on the opposite side of the housing with respect to the crankcase, or may be provided on both sides.

  FIG. 2 is a front view and a cross-sectional view of the compressor body of the air compressor according to the present embodiment. 2B is a front view of the compressor body, and FIG. 2A is a cross-sectional view taken along the line AA in FIG. 2B.

  In the present embodiment, a plurality of ventilation holes 29 in the first embodiment are provided, and a rib for reinforcing the housing 24, a stator 23, and a fixing portion for fixing the housing 24 are provided on the connection surface 28 between the plurality of ventilation holes. It is provided.

  In other words, in FIG. 2B, a plurality of ventilation holes 29 for allowing the cooling air 30 generated by the cooling fan 25 to pass through the connecting surface 28 connecting the outer peripheral surface 26 of the crankcase 1 and the outer peripheral surface 27 of the housing 24 are provided. The rib 31 for reinforcing the housing 24, the stator 23, and the fixing portion 32 of the housing 24 are provided on the connection surface 28 between the plurality of vent holes, and the fixing portion 32 is provided as shown in FIG. The stator 23 is fastened to the housing 24 with bolts 33.

  This is because, when the diameter of the housing for fixing the stator that constitutes the motor is larger than the diameter of the crankcase, this housing is the part with the largest diameter. It is necessary to reduce the weight as much as possible. However, if the housing becomes thin due to insufficient rigidity, noise or abnormal noise due to motor vibration or fatigue failure of the housing may occur.

  The present embodiment is configured to solve the above, and the rigidity of the housing 24 can be efficiently improved by directly reinforcing the fixing portion 32 of the stator 23 with the ribs 31. It is possible to suppress vibration, noise, and fatigue failure of the housing 24 and to ensure high reliability.

  FIG. 3 is a front view and a cross-sectional view of the compressor main body of the air compressor according to this embodiment. 3B is a front view of the compressor body, and FIG. 3A is a cross-sectional view taken along line AA of FIG. 3B.

  The present embodiment is characterized in that, in the first or second embodiment, the vent hole 29 is provided at a position between the coils 30 wound around the stator 23 on the connection surface 28.

  That is, in FIGS. 3A and 3B, at a position between the coil 34 wound around the stator 23 of the connection surface 28 that connects the outer peripheral surface 26 of the crankcase 1 and the outer peripheral surface 27 of the housing 24. A ventilation hole 29 through which the cooling air 30 generated by the cooling fan 25 passes was provided.

  As a result, the cooling air 30 generated by the cooling fan 25 and passed between the coils 34 of the stator 23 is straightly removed from the vent hole 29, so that the cooling performance of the stator 23 can be improved.

  FIG. 4 is a front view of the compressor body of this embodiment and a schematic view of a casting mold. 4B is a front view of the compressor main body, and FIG. 4A shows a casting mold of the crankcase 1.

  In this embodiment, the direction in which the rib 31 for improving the rigidity of the flange 24 is formed in the embodiment 2 or 3 is formed in the same direction as the direction in which the crankcase 1 is cast or the parting line. Features.

  That is, in FIG. 4B, the rib 31 for improving the rigidity of the flange 24 is formed on the connection surface 28 that connects the outer peripheral surface 26 of the crankcase 1 and the outer peripheral surface 27 of the housing 24. The housing and the crankcase are integrally formed by a casting mold. Therefore, the rib 31 is formed in the same direction as the drawing direction of the casting dies 35, 36, 37 of the crankcase 1 or the parting line shown in FIG.

  As a result, there is no need to consider the undercut of the casting mold of the rib 31, and the rib 31 can be formed with a thickness necessary to ensure the rigidity of the housing 24, so that the waste is reduced, and the manufacturing is light and inexpensive. It becomes possible to do.

  FIG. 5 is a cross-sectional view of the compressor body of the fifth embodiment.

  In this embodiment, in the first to fourth embodiments, a first cooling fan 25 is provided on the opposite side of the crankcase 1 with respect to the housing 24, and a second cooling fan 38 is provided on the opposite side of the housing 24 with respect to the crankcase 1. It is arranged, and the cooling air 39 between the cooling fans 25 and 38 flows in one direction.

  As a result, the cooling air 30 generated by the cooling fan 25 is pulled by the cooling fan 38 on the opposite side, so that it can easily pass between the coils 34 of the stator 23 and the air holes 29. It is possible to improve.

  In addition, since it is possible to improve the cooling performance of the cylinders 4 and 7, the air valves 5 and 8, and the cylinder heads 6 and 9, it is possible to improve the performance and reliability of the compressor body.

  Although the embodiments have been described above, the present invention is not limited to the above-described embodiments, and includes various modifications. For example, the above-described embodiments have been described in detail for easy understanding of the present invention, and are not necessarily limited to those having all the configurations described. Further, a part of the configuration of one embodiment can be replaced with the configuration of another embodiment, and the configuration of another embodiment can be added to the configuration of one embodiment. Moreover, it is also possible to add, delete, and replace other configurations for a part of the configuration of each embodiment.

1: crankcase,
2, 3: flange,
4, 7: Cylinder,
5, 8: Air valve,
6, 9: Cylinder head,
10: bearing box,
11, 12: bearing,
13: shaft,
14, 15: piston,
16, 17: connecting rod,
18, 19: eccentric member,
20, 21: bearing,
22: Rotor,
23: stator,
24: Housing,
25: Cooling fan,
26: outer peripheral surface of the crankcase,
27: outer peripheral surface of housing,
28: connection surface,
29: Vent hole,
30: Cooling air,
31: Rib,
32: fixed part,
33: Bolt,
34: Coil,
35, 36, 37: casting mold,
38: Cooling fan,
39: Cooling air

Claims (5)

A piston that reciprocates in the cylinder;
A crankcase that houses the drive of the piston;
A cooling fan that generates cooling air;
A motor for driving the piston and the cooling fan;
With
A housing for fixing the stator that constitutes the motor is provided on one end side of the crankcase and is integrally formed;
The outer diameter of the housing is larger than the outer diameter of the crankcase,
An air compressor characterized in that a vent hole through which the cooling air passes is provided on a connection surface connecting the outer peripheral surface of the crankcase and the outer peripheral surface of the housing. The air compressor according to claim 1,
A plurality of the vent holes are provided in the connection surface,
An air compressor characterized in that a rib for reinforcing the housing and a fixing portion for fixing the stator to the housing are provided between the plurality of vent holes. The air compressor according to claim 2,
The air compressor according to claim 1, wherein the rib is provided at a position coinciding with a direction in which the crankcase is cast or a parting line. The air compressor according to any one of claims 1 to 3,
The air compressor according to claim 1, wherein the ventilation hole is provided at a position between the coils wound around the stator on the connection surface. An air compressor according to any one of claims 1 to 4,
A first cooling fan is disposed on the opposite side of the crankcase with respect to the housing, and a second cooling fan is disposed on the opposite side of the housing with respect to the crankcase, so that the cooling air between the cooling fans is uniform. An air compressor characterized by flowing in a direction.

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