JPH11280653A - Portable compressor - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a portable compressor which can be miniaturized, at a low cost. SOLUTION: In a portable compressor composed of an electric motor 1, a compressor portion 2 driven by the electric motor 1 via a power transmission portion, an air tank 3 which stores compressed air generated by the compressor portion 2, the electric motor 1 and the power transmission portion are housed in and supported by a pair of housings, a first housing 5 and a second housing 6, which form a divided housing 4. The air tank 3 is formed between the second housing 6 and a third housing 7 that overlaps on the outside of the second housing 6.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a portable compressor comprising an electric motor, a compression section driven by the electric motor via a power transmission section, and an air tank for storing compressed air produced by the compression section. It is.

[0002]

2. Description of the Related Art As such a portable compressor, there is one described in a patent by the present applicant (Japanese Patent Publication No. 62-21998). This is because an electric motor and a power transmission unit (hereinafter, these electric motor and power transmission unit are referred to as a drive unit) are arranged in parallel with an air tank, and both ends of the air tank and the drive unit are constituted by a cylinder and the like. In addition, auxiliary devices such as a pressure reducing valve and a pressure switch are attached to a space formed on the other end side of the air tank and the driving unit while being connected via a connecting member. The air tank is generally formed by welding two or more steel plates or aluminum plates into a substantially cylindrical shape by welding.

[0003]

In the above-mentioned portable compressor, since the driving unit and the air tank are connected via the compression unit and the connecting member, the direction in which the driving unit and the air tank are parallel to each other is determined. It becomes longer in the vertical direction, and miniaturization is difficult. Further, a mounting seat for mounting the auxiliary device to the air tank is formed on the air tank by means such as welding, but this formation is time-consuming. In addition, because the number of components of the air tank is large and it is joined by welding,
There is a drawback in that it takes a lot of time and effort to form the compressor, and as a result, it is difficult to reduce the size of the compressor, resulting in an expensive portable compressor.

An object of the present invention is to eliminate the above-mentioned drawbacks of the prior art and to provide an inexpensive portable compressor that can be reduced in size.

[0005]

SUMMARY OF THE INVENTION An object of the present invention is to accommodate and support an electric motor and a power transmission unit by a first housing and a second housing which constitute a pair of split housings, and to provide a second housing and a second housing. This is achieved by forming an air tank between the outer housing and the third housing.

[0006]

DESCRIPTION OF THE PREFERRED EMBODIMENTS The present invention will be described below with reference to the drawings showing one embodiment. The rotation of the motor 1 is transmitted to a drive shaft 10 on which the gear 9 is mounted via a pinion 8 provided at the tip of the motor shaft and a gear 9 meshing with the pinion 8, and the rotation of the drive shaft 10 is further transmitted via a coil spring 11. The output shaft 12 is transmitted to the output shaft 12, and the output shaft 12 reciprocates the piston 14 via the connecting rod 13. When the piston 14 descends in the cylinder 15, the pressure in the cylinder 15 becomes negative, and an intake valve (not shown) provided in the cylinder head 16 opens, and the cylinder 15 is moved through the air intake 28, the crank chamber 18, the pipe 19, and the cylinder head 16. When the air is drawn into and the piston 14 rises, the intake valve closes,
When the air in the cylinder 15 is compressed and pressurized and reaches a predetermined pressure, an exhaust valve (not shown) provided in the cylinder head 16 is opened, and the compressed air is accumulated in the air tank 3 via the cylinder head 16 and the pipe 17. . Cylinder head 1
The flow paths of the air in the intake and the exhaust in 6 are independent from each other. The compressed air stored in the air tank 3 is supplied to an air-powered tool such as a nail driver (not shown) via a pressure reducing valve 21 and a socket 27 as shown in FIG. Drive shaft 10 and output shaft 1
2 are connected via the coil spring 11,
As described in Japanese Patent Application No. 9-357249 filed earlier by the present applicant, a load fluctuation at a high torque acting on the output shaft 12 when the piston 14 reciprocates is absorbed by the coil spring 11, and the drive shaft 10 Gear noise, wear, and breakage transmitted to the gear 9 and generated between the gear 9 and the pinion 8 are reduced or prevented. Further, a flywheel 20 is mounted on the output shaft 12 so as to suppress the rotation fluctuation of the output shaft 12 by the rotational inertia force of the flywheel 20 and to provide a cutout portion 29 in the flywheel 20 to constitute a counterweight.

A housing 4 for accommodating and supporting a power transmission unit such as the motor 1 and the drive shaft 10 and the output shaft 12, that is, a drive unit, is a first housing constituting a so-called split housing divided by a plane parallel to the axial direction. 5. The second housing 6 is formed by the housings 5 and 6. The housings 5 and 6 also constitute a crank chamber 18 of the compression unit 2 and extend outside the second housing 6 of the crank chamber 18 in a direction perpendicular to the axial direction. Is attached. A concave portion is provided outside a portion of the second housing 6 other than the compression portion 2 such as the cylinder 15, and the third housing 7 is mounted via a bolt 22 in accordance with the concave portion, so that the outside of the second housing 6 and the third housing 7 Form the air tank 3. A groove is provided on the entire circumference of the mating surface between the third housing 7 and the second housing 6, and a packing 23 having a sufficient interference is fitted into the groove when the second housing 6 and the third housing 7 are mated. This prevents the compressed air from leaking from the mating portion of the housings 6 and 7. The housing 5-7
Is formed, for example, from a casting such as aluminum die-casting. The compression section 2 is provided beside the third housing 7, and its height is substantially the same as the height of the third housing 7.

[0008] Since the housing 4 is formed by two divided housings 5 and 6 divided by a plane parallel to the axial direction, the motor 1 and the power transmission unit are set in the second housing 6 side by side.
By attaching the first housing 5, the assembly of the electric motor 1 and the power transmission unit is completed, so that the assembly is facilitated. The drive shaft 10 and the output shaft 12 are positioned in the axial direction by a retaining ring 24 fitted in grooves provided in the housings 5 and 6, and at the same time, the retaining ring 24 is provided with iron powder and the like generated by the coil spring 11 in the crank chamber 18 and the gear chamber. 25 to prevent intrusion.

The air tank 3 has a split structure comprising a second housing 6 and a third housing 7. Since the second housing 6 is a housing constituting the split housing 4, the number of components of the air tank 3 is reduced. Reduced and second
Since the housing 6 and the third housing 7 are bolted via the packing 23, welding work is unnecessary, and at the same time, the second housing 6 forms the split housing 4 and the air tank 3, so that the conventional air tank is not used. The mounting for mounting the air tank to the housing, which has been joined by welding, and the welding work are also unnecessary. Also, the air tank 3 is
By arranging it in the space generated by the protrusion from the housing 6, it is possible to reduce the size. Further, as shown in FIG. 1, the second housing 6 has a concave portion in, for example, a bearing portion, and the capacity of the air tank 3 is increased by the concave portion. Further, the housing 4 and the air tank 3 are not cylindrical, and the dead space around the overlapping portion, which is inevitably generated when these are overlapped in a cylindrical shape, that is, the portion C shown in FIG. 5 can be used as the air tank 3. The capacity of the air tank 3 can be further increased.

Auxiliary devices such as the pressure reducing valve 21 and the pressure switch 26 are also provided in the housing 6 forming the air tank 3.
By integrally providing the mounting seat to the air tank 3 by casting, the direct mounting to the air tank 3 becomes possible, and the auxiliary equipment mounting seat and welding work conventionally joined by welding to the air tank become unnecessary. Further, by arranging the auxiliary device in the stepped portion 30 formed by the pinion 8 and the gear 9, it is possible to prevent the auxiliary device from going on a business trip, and to further reduce the size of the portable compressor.

[0011]

As described above, according to the present invention, the first housing to the third housing form the housing for accommodating and supporting the electric motor, the drive unit and the like, and the air tank, and the height of the third housing is reduced by the compression unit. , The portable compressor can be formed with a small number of parts and a compact compressor that can be reduced in size can be provided at low cost.

[Brief description of the drawings]

FIG. 1 is a sectional view showing an embodiment of a portable compressor according to the present invention.

FIG. 2 is a sectional view taken along line AA of FIG.

FIG. 3 is a side view of FIG. 1;

FIG. 4 is a front view of FIG. 1;

FIG. 5 is a sectional view taken along line BB of FIG. 1;

[Explanation of symbols]

1 is an electric motor, 2 is a compression unit, 3 is an air tank, 4 to 7 are housings, 8 is a pinion, 9 is a gear, 10 is a drive shaft, 1
1 is a coil spring, 12 is an output shaft, 13 is a connecting rod, 1
4 is a piston, 15 is a cylinder, 16 is a cylinder head, 20 is a flywheel, 22 is a bolt, and 23 is packing.

Continued on the front page (72) Inventor Tsukasa Suzuura 1060 Takeda, Hitachinaka-shi, Ibaraki Prefecture Within Hitachi Koki Co., Ltd.

Claims (4)

[Claims] 1. A portable compressor comprising an electric motor, a compression section driven by the electric motor via a power transmission section, and an air tank for storing compressed air produced by the compression section. The first housing and the second housing constituting the split housing house and support the electric motor and the power transmission unit, and form an air tank between the second housing and the third housing superposed on the outside of the second housing. A portable compressor characterized in that: 2. The portable compressor according to claim 1, wherein said first to third housings are formed by casting. 3. The portable compressor according to claim 1, wherein the compression section is located on a side of the third housing, and has a height substantially equal to a height of the third housing. 4. A groove is provided around the entire mating surface of the second housing and the third housing, and a sealing material is inserted into the groove, so that the second housing and the third housing are connected via a fastening member. The portable compressor according to claim 1.