JPH055264Y2 - - Google Patents

Description

[Detailed Description of the Invention] (Industrial Application Field) The present invention relates to an improvement of an air pump unit used in a closed-loop pneumatic circuit.

(Prior Art) Some devices that utilize air pressure are equipped with an air pump unit to obtain the necessary pressure. Such an air pump unit is composed of, for example, a compressor and a motor that drives it, and when the motor is driven, the compressor sucks in air from an inlet opening into the atmosphere, pressurizes it, and then connects it to a discharge outlet. It is now being supplied to

Also, when it is desired to lower the pressure in the equipment, the high pressure air inside the equipment supplied from the compressor is released into the atmosphere.

(Issues for the design) However, in this so-called open circuit, where high-pressure air is supplied by pressurizing the atmosphere and is released into the atmosphere when it is no longer needed, the compressor tends to suck in dust and water along with the atmosphere. There was a problem that the internal parts of equipment such as valves installed in the system were susceptible to wear and corrosion. For this reason, particularly for those used in places with a lot of dust or on the sea, their structures and materials are required to have wear resistance and corrosion resistance, which results in an increase in costs.

On the other hand, if we use a so-called closed-loop system in which the compressor's suction air is supplied from a separate air tank and the unnecessary pressurized air is returned to this air tank, this problem does not occur because the compressor does not suck in outside air. In this case, a space is required to provide an air tank, which increases the size of the entire device.

The present invention was devised in view of the above-mentioned problems, and an object of the present invention is to provide a closed-loop air pump unit including an air tank in a compact form.

(Means for achieving the object) A compressor and a motor for driving the compressor are arranged inside an air tank configured to be expandable and retractable using an elastic material, and the suction port of the compressor is opened inside the air tank. An accumulator is installed at the discharge port of the air tank, and a valve is provided to switch and connect the air supply port for external equipment provided in the air tank to the compressor discharge port and the inside of the air tank. It is equipped with a pressure switch that energizes the motor.

(Function) When the valve is switched, the accumulator immediately supplies the stored compressed air to the external equipment from the air supply port. The pressure switch energizes the motor based on the drop in pressure in the accumulator, and the compressor driven by the motor supplies air in the air tank under pressure to the accumulator to compensate for the drop in accumulated pressure.

Furthermore, when the air supply port is connected to the inside of the air tank by switching the valve, pressurized air that has been supplied to external equipment flows back into the air tank.

The air tank made of elastic material functions as a protection material for the motor, compressor, etc. disposed inside, as well as a soundproofing material.

(Example) Embodiments of the present invention are shown in FIGS. 1 to 3.

In FIG. 1, 1 is a compressor, and 2 is a motor for driving the compressor 1, which is integrally mounted on a base 3 via a bracket. The outer periphery of this base 3 is closely contacted with the periphery of an elastic cover 4 made of rubber that covers the upper part. It is stored inside the 5.

The compressor 1 internally pressurizes the air sucked in from the suction port 6 by driving the motor 2, and
The suction port 6 opens into the air tank 5, and the discharge port 7 is connected via a conduit 8 to an accumulator 9 also provided inside the air tank 5.

Further, solenoid valves 11 and 12 are provided as valves for switching and connecting the air supply port 10 opened to the base 3 to the accumulator 9 and the inside of the air tank 5. Solenoid valve 11
The piping 14 from the storage unit 9 and the piping 15 leading to the air supply port 10 are connected or disconnected as shown in FIG. 3 depending on the external energization. The solenoid valve 12 is interposed in the middle of the piping 15,
Similarly, the piping 15 and the inside of the air tank 5 are communicated with each other or cut off by applying electricity from the outside.

A pressure switch 16 is attached to the accumulator 9, which operates according to the accumulated pressure. This pressure switch 16 is connected to an electric wiring 1 led from the outside to the motor 2.
When the pressure of the accumulator 9 falls below a certain level, this electrical wiring 17 is made conductive to supply electricity to the motor 2, but when the pressure of the accumulator 9 rises above a certain level, Electrical wiring 1
Cut off the continuity of 7.

Note that 18 is a relief valve that releases pressure into the air tank 5 when the discharge pressure of the compressor 1 increases abnormally.

Next, we will explain the function of this air pump unit in a third manner.
Application to the power tilt cylinder device for an outboard motor shown in the figure will be explained as an example.

In FIG. 3, 30 is an air pump unit having the above configuration, and 31 is an air pump unit 3.
32 is a power tilt cylinder interposed between the outboard motor and the hull for rotation of the outboard motor. .

The power tilt cylinder 32 has a hollow piston rod 35 slidably inserted into a cylinder 33 filled with hydraulic oil via a bearing 34, and a piston 36 supported at the tip of the piston rod 35. 36 defines front and rear oil chambers 37 and 38. The hollow portion 35A of the piston rod 35 communicates with the oil chamber 38,
It also communicates with the oil chamber 40 of the accumulator 31 via a conduit 39 connected to the base end.

The piston 36 has an oil chamber 3 facing the hollow part 35A.
A check valve 41 is provided which is biased by a spring 41A from the 7 side. Further, an operating rod 42 for forcibly opening the check valve 41 by external operation passes through the hollow portion 35A vertically and projects outward from the piston rod 35 in the axial direction. An operating lever 45 rotatably attached to a bracket 46 at the proximal end of the piston rod 35 comes into contact with the protruding end of the operating rod 42.

The accumulator 31 houses a free piston 43 therein so as to be able to slide freely.
An oil chamber 40 and an air chamber 44 are defined on both sides of 3. The oil chamber 40 is connected to the conduit 39 leading to the power tilt cylinder 32 as described above, and the air chamber 4
4 is the air supply port 10 of the air pump unit 30
connected to.

When extending the power tilt cylinder 32,
Solenoid valve 1 of air pump unit 30
1 is opened and the solenoid valve 12 is closed, the compressed air stored in the accumulator 9 is immediately supplied from the air supply port 10 to the air chamber 44 of the accumulator 31. This compressed air causes the free piston 43 to slide to the right in FIG. 3, causing the oil chamber 40 on the opposite side to contract. Along with this, the internal hydraulic oil passes through the pipe 39 to the power tilt cylinder 3.
2, and the hollow part 35A of the piston rod 35
The oil chambers 37 and 38 in the cylinder 33 are reached through the oil chambers 37 and 38 in the cylinder 33. At this time, the check valve 41A is opened by pressure from the hollow portion 35A to allow hydraulic oil to flow into the oil chamber 37.

In this way, as the oil pressure in the oil chambers 37 and 38 increases, the piston rod 35 is driven in the extension direction while supporting the load applied from the outboard motor.

On the other hand, in the air pump unit 30, when the pressure in the accumulator 9 drops below a certain level due to the supply of compressed air, the pressure switch 16 switches to energize the motor 2. As a result, the compressor 1 starts operating, sucks in the air in the air tank 5 through the suction port 6, and supplies pressurized air to the accumulator 9 through the discharge port 7. The air tank 5 contracts as the air stored therein is sucked into the suction port 6.

In this way, the power tilt cylinder 32 is extended and driven by the accumulated pressure in the accumulator 9, and the decrease in the accumulated pressure in the accumulator 9 is compensated for by the operation of the compressor 1.
As soon as the power tilt cylinder 32
expands rapidly. Therefore, even if a small compressor 1 is used, the outboard motor can be rotated in a short time.

Now, when the piston rod 35 has extended to the required position, if the solenoid valve 11 of the air pump unit 30 is shut off, the supply of pressurized air to the air chamber 44 is stopped, and the flow of hydraulic oil into the power tilt cylinder 32 is also stopped. Extension of the power tilt cylinder 32 is stopped.

In this state, the outboard motor is powered by power tilt cylinder 3.
Check valve 41 for the contraction pressure exerted on
The oil chamber 37, which is prevented from leaking hydraulic oil, is connected to the piston 3.
6 and lock the power tilt cylinder 32.
It prevents the contraction of. Therefore, even if the solenoid valve 12 is opened in this state and the high pressure air in the air chamber 44 is returned to the air tank 5, the power tilt cylinder 32 is maintained at the extended position.

To retract the power tilt cylinder 32,
The operating rod 42 is pushed into the piston rod 35 by manual operation of the operating lever 45, and the check valve 41 is forcibly opened. As a result, the hydraulic oil in the oil chamber 37 flows into the oil chamber 40 of the accumulator 31 through the hollow part 35A and the pipe 39, and the piston rod 35 and the piston 36 move into the cylinder 3.
Invade 3. At this time, a portion of the hydraulic oil flowing back into the accumulator 31 from the oil chamber 37 flows into the expanding oil chamber 38 .

Furthermore, within the accumulator 31, the free piston 43 slides to the left in FIG. As a result, the air tank 5 returns to its original state.

Note that when you want to stop the power tilt cylinder 32 in the middle of contraction, if you stop pushing the operating rod 42 using the operating lever 45, the check valve 41 will close and prevent the hydraulic oil from flowing out from the oil chamber 37. , piston 36 and piston rod 35 are supported in that position.

In this way, the compressed air that drives the power tilt cylinder 32 is supplied and recovered in a closed loop that is completely cut off from the outside air, so dust and water in the outside air are sucked into the compressor 1 of the air pump unit 30. Therefore, there is no risk that the interior of the compressor 1, solenoid valve 11, etc. will be abraded or corroded by such dust or water. Furthermore, since all the components of the air pump unit 30 are housed inside the air tank 5 sealed with the rubber cover 4,
The equipment is highly rust-proof even on ships, where it is easily exposed to rainwater and seawater, and the noise level during operation is low.

Furthermore, since the compressor 1 and motor 2 are housed within the air tank 5, there is no need to secure a separate space for these when installing the air pump unit 30, and the air pump unit 30 can be installed even in a small space. be.

In this embodiment, since the spring load of the spring 41A of the check valve 41 is set low, when an external tension force is applied to the power tilt cylinder 32 in the stopped state, the check valve 41
opens, the power tilt cylinder 32 extends, and does not return to its original position even after the action of the extension force stops. On the other hand, if the spring load of the spring 41A is strengthened, the supporting force and restoring force against the externally applied extension force will be strengthened, instead of requiring the pushing operation of the operating rod 42 even when driving the power tilt cylinder 32 to extend. be done.

(Effects of the invention) As described above, the air pump unit of the invention houses component equipment such as a compressor and a motor inside the air tank, and also has an accumulator interposed at the discharge port of the compressor. Equipped with a pressure switch that energizes the motor in response to a drop in pressure in the accumulator, the accumulation of pressure in the accumulator allows the supply of pressurized air to external equipment to be started immediately by simply switching the valve, and the drop in pressure in the accumulator is eliminated. This is supplemented by the compressor supplying the air in the air tank to the accumulator under pressure by operating the motor via the pressure switch.

Therefore, a large amount of pressurized air can be supplied in a short time using a small compressor, and a compact and powerful closed-loop pressurized air supply circuit can be formed.

In addition, since it is a closed loop, there is no risk of dust or water being sucked into the compressor, and since the air tank functions as a protective material for the internal equipment, the durability of the component equipment is good, and it can be used in places with a lot of dust or at sea. It can withstand use under environmental conditions.

Furthermore, since the motor and compressor are housed in the air tank, there is less noise during operation.

[Brief explanation of the drawing]

Fig. 1 is a vertical cross-sectional view of an air pump unit showing an embodiment of the present invention, Fig. 2 is a cross-sectional view of the same, and Fig. 3 is a cross-sectional view of a power tilt cylinder device for an outboard motor constructed according to the same embodiment. FIG. 1...Compressor, 2...Motor, 5...Air tank, 6...Suction port, 7...Discharge port, 9...
...Accumulator, 10...Air supply port, 1
1, 12... Solenoid valve, 16... Pressure switch, 30... Air pump unit, 31...
...Accumulator, 32...Power tilt cylinder.

Claims (1)

[Scope of utility model registration request] A compressor and a motor that drives the compressor are arranged inside an air tank that is made of elastic material so that it can expand and contract, the suction port of the compressor is opened inside the air tank, and an accumulator is inserted into the discharge port of the compressor. It is equipped with a valve that switches and connects the air supply port for external equipment provided in the air tank to the compressor discharge port and the inside of the air tank, and a pressure switch that energizes the motor based on the pressure drop in the accumulator. An air pump unit characterized by: