JPS581612B2 - dehumidifier - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a dehumidifying device used in a refrigerated air dryer or the like to remove moisture from compressed air.

A conventional refrigerating air dryer is constructed as shown in FIG.

That is, in the figure, 1 is a compressor, 2 is a condenser, 3 is a capillary tube, 4 is a cooler, 5 is a pressure-sensitive bypass valve (not shown), 6 is a precooler, and 7 is a dehumidifier.

The precooler 6 is formed by connecting an inlet pipe 6b to the pressure vessel 9a, having an outlet pipe 6c attached therethrough, and attaching a large number of fins 6d to the outlet pipe 6C.

In the dehumidifier 7, a pressure vessel 7a housing the cooler 4 is provided with a communication pipe 7b that communicates with the pressure vessel 6a, and a communication pipe 7C and a drain outlet pipe 7d that communicate with the outlet pipe 6c are connected. A heat insulating material 8 is provided around the outer periphery of the pressure vessel 7a.
It is formed by being coated with.

In this device, the moist compressed air introduced from the introduction pipe 6b is pre-cooled through the cold compressed air coming out from the dehumidifier 7 and the fins 6d, and the pre-cooled compressed air is transferred to the cooler 4. After being cooled and dehumidified, the compressed air is heated while passing through the precooler 6 again and is discharged as dry compressed air.

However, the conventional structure shown in FIG. 1 requires two pressure vessels 6a and 7a, which has the disadvantage of requiring double labor and high costs for manufacturing. 7a, the pressure vessel 7a becomes quite bulky, and the outer surface of the pressure vessel 7a must be covered with a fairly thick insulating material 8 to prevent condensation, which may hinder the overall size of the pressure vessel 7a. Furthermore, the use of the heat insulating material 8 has the problem of complicating assembly and increasing costs.

Because of this, in the past
A dehumidifying device as seen in Japanese Patent Publication No. 75069 has been developed.

This dehumidification device has two cylinders, an outer cylinder and an outer cylinder, concentrically placed inside a single pressure vessel.1 A pre-cooling passage is formed between the pressure vessel and the outer cylinder, and a cooling passage is formed between the outer cylinder and the inner cylinder. Passage configuration 1 Compressed air is introduced from the outside into a precooling tube formed in the precooling passage, the compressed air is precooled, the precooled air is passed through a filter to remove dust, and then passed through the cooling passage. The compressed air is dehumidified by being cooled by a cooling pipe arranged in the cooling passage, and then this dehumidified air is taken out to the outside through a pre-cooling passage.

However, in the dehumidifying device disclosed in the above-mentioned publication, both the pre-cooling tube and the cooling tube are simply pipe-shaped, and therefore, the heat exchange rate is extremely low.

In addition, the air to be dehumidified contains dust, oil, etc., so a filter is used in the above publication to remove this dust, but the filter is easily clogged by dust, oil, moisture, etc. Therefore, the filter needs to be replaced or cleaned regularly or irregularly, and its maintenance is extremely troublesome.

The present invention was developed based on these circumstances, and its purpose is to provide a device that has excellent heat exchange efficiency, extremely high dehumidification ability, excellent dust removal ability, and requires almost no maintenance such as cleaning. The present invention aims to provide a dehumidifying device that is easy to handle.

An embodiment of the present invention will be described below with reference to FIGS. 2 and 3.

In Fig. 2, 11 is a compressor, and between its discharge port and suction port are a condenser 12, an auxiliary condenser 13, and a capillary tube 1.
4. The cooling pipe 15 and the auxiliary evaporator 16 are connected in series to form a refrigeration circuit.

A fan motor 12a is arranged near the condenser 12, and its rotation is controlled by a signal from a temperature sensor (not shown), so that the heat is mainly discarded in the condenser 12 or is discarded in the auxiliary condenser 13. It has become.

The auxiliary condenser 13 and the auxiliary evaporator 16 form a reheater 17 with a double-tube structure, in which the refrigerant that has passed through the cooling pipe 15 flows through the inner tube, and between the inner tube and the outer tube. The refrigerant that has passed through the condenser 12 flows through the annular portion, thereby heating the refrigerant returning from the cooling pipe 15 to the compressor 11 to prevent liquid back.

Further, reference numeral 18 is a cooling passage that houses the cooling pipe 15, and this and the cooling pipe 15 form a dehumidifier.

Further, reference numeral 19 is a pre-cooling passage through which cold air that has passed through the cooling passage 18 flows, and a pre-cooling pipe 20 through which compressed air toward the cooling passage 18 passes is housed inside, and these pre-cooling passages 1'9 and the pre-cooling pipe 20 represents a precooler.

A dehumidifying device 21 is formed by the precooler and the dehumidifier.

This dehumidifying device 21 will be explained in detail in FIG. 3. In the figure, 22 indicates, for example, a vertical pressure vessel 1. Tube plates 23 and 24 are attached to the upper and lower ends of the vessel 21, respectively. The inside of the pressure vessel 22 is introduced into the introduction chamber 22a1 and the inversion chamber 2.
2b and a processing chamber 22c between them.

An air outlet 25 communicating with the lower end of the processing chamber 22c is attached to the lower side of the pressure vessel 22, and an air inlet 26 communicating with the introduction chamber 22a is attached to the lower surface.

An inner cylindrical body 27 is attached to the upper tube plate 23 so as to be continuous with the opening 23a, and its lower end is separated from the lower tube plate 24.

Furthermore, an outer cylinder 28 is attached to the lower tube plate 24 and surrounds the inner cylinder 27.
A cooling passage 18 is formed between the outer cylindrical body 28 and the outer cylindrical body 28.
A pre-cooling passage 19 surrounding the cooling passage 18 is formed between the cooling passage 18 and the pressure vessel 22 .

The lower end of the pre-cooling passage 19 opens to the air outlet 25, and the upper end communicates with the upper end of the cooling passage 18. As a result, compressed air is distributed in a meandering manner.

In addition, the lower tube plate 24 is provided with a drain hole 24a, and a drain pipe 28 connected to the drain hole 24a and whose lower end is led out of the pressure vessel 22 is attached.

In addition, it is preferable that the lower tube plate 24 has an inclined structure that gradually becomes lower toward the drain hole 24a, and
The drain pipe 28 is provided with a through hole 28a for draining water accumulated in the introduction chamber 22a.

Moreover, the cooling pipe 15 housed in the cooling chamber 18 is connected to the inner cylinder body 2.
The cooling tube body 15a is wound in a spiral manner around the circumference of the cooling tube body 15a, and the cooling fins 15b are attached to the outer circumference of the cooling tube body 15a.

The cooling fins 15b are, for example, so-called spine fins formed by providing a large number of slits along the thickness of a steel strip, and are wound spirally around the outer periphery of the cooling tube body 15a.

The lower ends of the cooling pipe bodies 15a respectively penetrate the upper and lower walls of the pressure vessel 22, protrude to the outside, and are connected to the refrigeration circuit.

Furthermore, the precooling tube 20 housed in the precooling passage 19 is connected to the outer cylindrical body 2.
It has a coil shape that is wound in a spiral shape along the circumference of the tube 8, and is formed from an air tube body 20a through which compressed air flows and heat exchange fins 20b attached to the outer periphery of the air tube body 20a.

The aforementioned spine fin is used as the heat exchange fin 20b.

The upper end 20a' and the lower end 20 of the air pipe body 20a
a'' opens into the reversing chambers 22b and 22a, respectively.

At least one pre-cooling tube 20 is stored in the pre-cooling passage 19, and a plurality of pre-cooling tubes 20 are stored in the pre-cooling passage 19 depending on the required pre-cooling capacity.If a plurality of pre-cooling tubes 20 are stored, the winding start positions are shifted from each other and the outer cylindrical body 28 wrapped around the outer circumference of the

Further, a dust removal passage 27a in the inner cylinder 27 has a baffle plate 2.
9 and buff-full plates 30 having a smaller diameter are alternately arranged.

The large-diameter buff-full plate 29 has a through hole 29a in its center, and its peripheral edge is fixed to the inner circumferential surface of the inner cylinder 27. It is provided apart from this inner circumferential surface except for a portion (not shown) to which it is fixed.

Next, to explain the function of this dehumidifying device 21, the refrigerant of the refrigeration circuit flows through the cooling tube body 15a of the cooler 15, and evaporates there, eventually taking away the heat from the surrounding area via the cooling fins 15b. It turns out.

On the other hand, the high-temperature saturated compressed air fed from the air compressor enters the introduction chamber 22a of the pressure vessel 22 from the air supply 26, and the lower end 20a of the air pipe body 20a opens there. and its upper end 2
It flows out from 0a' into the reversing chamber 22b.

After that, the dust removal passage 2 inside the inner cylinder body 27 is turned downward.
7a is the first air flow, then reversed upward to flow through the cooling passage 18, and then reversed downward again to flow through the pre-cooling passage 19 and flow out from the air outlet 25 to the outside of the pressure vessel 22. Provided for use with equipment (not shown).

Therefore, since cold air flows through the precooling passage 19 on the downstream side of the cooling passage 18, in this precooling notification 9, the moist compressed air passing through the air pipe body 20a and the cold compressed air exchange heat via the heat exchange fins 20b. do.

Through this primary exchange, the compressed air passing through the air pipe body 20a is precooled, and the dehumidified cold compressed air is heated to become dry compressed air.

In addition, when the compressed air pre-cooled in this way passes through the dust removal passage 27a of the inner cylinder 27, it is protected by baffle plates 29 and 30.
Since the flow rate is slow and fast and collides with the baffle plate 30, mainly large and heavy dust, rust, oil, etc. contained in the air are coagulated and separated.

Incidentally, such separated substances naturally move downward in the dust removal passage 27a and fall onto the lower tube plate 24 along with the air flow.

Then, while the compressed air that has been precooled and has foreign matter (dust, etc.) removed as described above flows through the cooling chamber 18, it is cooled by exchanging heat with the refrigerant via the cooling fins 15b.

This cooling causes moisture in the compressed air to drain, and the compressed air cooled and dehumidified in this way is passed through the pre-cooling passage 1.
9.

On the other hand, after the drain drips onto the lower tube plate 24, it is drained out of the pressure vessel 28 from the drain pipe 28 together with the foreign matter.

By the way, in each heat exchange section, the cooling tube body 15a and the air tube body 20 are
Since a is wound in a spiral shape, the efficiency of heat exchange per unit area is extremely good.

Further, since the cooling passage 18 and the dust removal passage 27a using a baffle plate are housed in the space inside the pre-cooling passage 19, the arrangement is rational and there is no waste.

Therefore, due to these factors, the pressure vessel 22 itself can be made compact.

Since the outer periphery of the cooling passage 18 is surrounded by the pre-cooling passage 19, dew condensation does not occur on the pressure vessel 22 due to the insulation effect of the pre-cooling passage 19. There is no need for

The compressed air passing through the cooling passage 18 and the pre-cooling passage 19 is transferred to the dust removal passage 27a of the inner cylindrical body 27 through the full plate 29.
, 30 to mainly remove large and heavy dust, rust, oil, etc., before flowing into the cooling passage 18.

In addition, in the cooling passage 18, small and fine dust separated and cut in the dust removal passage 27a is collected on the cooling fin 15.
b, and is captured by this fin 15b.

The fine dust captured by the fin 15b is flushed away together with the drain.

Therefore, since the fins 15b of the cooling pipe 15 also perform a dust trapping function, there is no need for a highly capable foreign object trapping function in the dust removal passage 27a. This leads to the fact that only the separation action is required.

Therefore, the cooling pipe 15 and the precooling pipe 20 can stably exhibit the desired performance for a long period of time.

Furthermore, since the compressed air sent under pressure from the air compressor first passes through the air pipe 20a, the flow velocity in that part becomes extremely high, thus preventing foreign matter from adhering to the inner wall of the air pipe 20a. Therefore, the performance of the precooling tube 20 does not deteriorate.

Note that the present invention is not limited to the above-mentioned embodiment; for example, the outer cylinder body 28 itself may be made of a heat insulating material such as vinyl chloride, or a heat insulating cylinder made of the same material may be attached to the inner or outer surface of the outer cylinder body 28 for cooling. Preferably, heat exchange between the passage 18 and the precooling passage 19 is prevented.

As explained above, in this invention, the precooling pipe and the cooling pipe each having a radiation fin are arranged in a spiral shape in the precooling passage and the cooling passage, so that the heat exchange efficiency is extremely high.
Therefore, the dehumidifying ability becomes high.

Moreover, the heat dissipation fins have the function of capturing fine dust, and the captured dust is removed together with the drain.
It is only necessary to provide a buttful plate in the dust removal passage to separate bulky debris.

This eliminates the need for filters that are prone to clogging, and eliminates the need for troublesome maintenance such as replacing and cleaning filters, resulting in stable performance over a long period of time.

[Brief explanation of the drawing]

Fig. 1 is a principle diagram showing a refrigerating air dryer equipped with a conventional dehumidifying device, Fig. 2 is a refrigeration circuit diagram of a refrigerating dryer equipped with a dehumidifying device of the present invention, and Fig. 3 is an implementation of the dehumidifying device. It is a longitudinal side view which shows an example. 15... Cooling pipe, 18... Cooling passage, 19... Pre-cooling passage, 20
... Pre-cooling pipe, 21 ... Dehumidifier, 22 ... Pressure vessel, 23.2
4...Tube plate, 25...Air outlet, 26...Air outlet, 27...Inner cylinder, 28...Outer cylinder, 15b, 20b...Fin, 2
7a...Dust removal passage, 29, 30...Bullet full plate.

Claims (1)

[Claims] 1. Two cylinder bodies, an inner cylinder and an outer cylinder, are provided in the pressure vessel, and a pre-cooling passage is formed between the pressure vessel and the outer cylinder, a cooling passage is formed between the outer cylinder and the inner cylinder, and a dust removal passage is formed in the inner cylinder. Precooling pipes and cooling pipes having a large number of radial heat dissipating fins on the outer periphery are arranged spirally in the precooling passage and the cooling passage, respectively, and the dust removal passage has a meandering air flow. A large number of baffle plates are arranged alternately to change the shape, a low-temperature refrigerant is made to flow through the cooling pipe, compressed air to be dehumidified is introduced into the pre-cooling pipe, and after being pre-cooled, this air is passed through a dust removal passage. The air is then separated from dust and other particles, and then cooled and dehumidified by a cooling pipe in the process of passing through a cooling passage, and the dehumidified air is then taken out to the outside by passing through a pre-cooling passage. Dehumidification equipment.