JPH024190A - Vacuum drier - Google Patents

Abstract

PURPOSE:To prevent the adverse affection of a torsional vibration driving unit under a vacuum and drying materials without deteriorating the quality thereof by a method wherein the torsional vibration driving unit is arranged in atmosphere and bulk materials are circulated and dried on a spiral track in a sealed tank which receives only the torsional vibration force of the torsional vibration driving unit. CONSTITUTION:A vacuum drying unit 2 is supported by supporting pillars, established on a base table 8, through coil spring vibration insulators 7 fixed to the bottom of the vacuum drying unit 2. A vibration driving unit 3 consists of a driving unit mounting plate 4, fixed to the bottom wall of the vacuum drying unit 2 so as to be hanged, and a pair of vibration motors 5a, 5b, fixed to both surfaces of the driving unit mounting plate 4 so as to be slanted with a given angle in opposing directions with respect to a vertical axis. The pair of vibration motors 5a, 5b is driven under a predetermined evacuated pressure. According to this method, a torsional vibration force is generated and a main body 9, supported by the coil springs 7, generates torsional vibration whereby the materials to be dried are transferred on a spiral track 10 along the same.

Description

DETAILED DESCRIPTION OF THE INVENTION [Field of Industrial Application] The present invention relates to a vacuum drying apparatus used for drying bulk materials.

[Prior art and its problems]

For example, in the continuous vacuum drying apparatus described in Japanese Patent Publication No. 55-30195, a spiral component transport track is wound and fixed around the outer periphery of a central cylinder, and a screw second vibration drive is provided below this track. A so-called vibrating spiral elevator is used, which is entirely covered with a tank, and the inside of the tank is kept in a vacuum state, and the helical track is driven by the torsional vibration drive part to dry the bulk material. When the material is transferred and reaches the upper end of the truck, a branch pipe extending in the shape of a square cross protrudes outward from the tank at the upper end side, and the lower end is again inside the tank. is inserted into. For this reason, a vacuum seal is required for leading out the branch pipe to the outside of the tank and introducing it into the tank in order to maintain the vacuum inside the tank. A switching damper is disposed in this "1" shaped branch pipe, and when the bulk material is dried to a desired degree, this switching damper is opened, and the branch pipe is opened from the upper end of the spiral track. The material introduced into the tank is discharged to the outside by switching the switching damper.Therefore, in order to discharge the material to the outside from this switching damper, various downstream parts are used to maintain the vacuum level inside the tank. A vacuum sealing device must be used in the conventional device described above, in which the supply pipe is connected to a sealing device in the tank in order to supply the bulk material to be dried to the lower end of the track of the vibrating spiral elevator in the tank. has been fixed through.

In this way, conventional equipment requires vacuum sealing devices at various locations, which not only increases the number of parts but also
This greatly increases the cost of the entire device. Further, the entire so-called vibrating spiral elevator is covered with a closed tank, and although the structure of the screw vibrating drive section is not particularly specified, a pair of vibrating electric motors are generally used. As is well known, this photographic motor is equipped with unbalanced weights at both ends of the rotating shaft of the induction motor, and due to this rotation, each vibrating motor generates centrifugal force, and the pair of vibrating motors are connected to the same power source. Even if they are connected, different slips should occur, but so-called synchronization force acts to generate torsional vibration force. However, as is well known, vibrating electric motors use bearings to support the rotating shaft at both ends, or storage of grease, oil, or in some cases cooling oil in the rotating parts to ensure smooth rotation. ing. When such a torsional vibration drive unit is placed in a vacuum, especially if it continues to be driven for a long time, the entire body becomes hot due to coil heat, and oil and grease gas is released into the vacuum, causing the vacuum level to deteriorate. Not only will this cause deterioration, but if the material to be dried is food, it will contaminate it and reduce its quality.

[Problem that the invention seeks to solve]

The present invention has been made in view of the above-mentioned problems, and it is possible to prevent the adverse effects of the torsional vibration drive unit under vacuum, and also to provide a vacuum that allows bulk materials to be dried, such as food products, to be dried without deteriorating their quality. The purpose is to provide a drying device.

[Means for solving problems]

The above purpose is to provide a vacuum drying device in which bulk materials are transported by torsional vibration on a spiral track in a closed tank under reduced pressure and dried by circulation. Achieved by a vacuum drying device, characterized in that the bulk material is circulated and dried on the spiral track only in the closed tank which receives the torsional vibration force of the torsional pickup drive unit. be done.

[For production]

The torsional vibration drive unit is insulated from the inside of the sealed tank and placed in the atmosphere, so even if it becomes hot during operation and oil or grease gas is released, the vacuum inside the sealed tank will not drop. . Furthermore, the bulk material being circulated on the spiral track is not contaminated.

〔Example〕

Hereinafter, a circulating vacuum drying apparatus according to an embodiment of the present invention will be described with reference to the drawings.

1 to 4 show a first embodiment. In these figures, the circulating vacuum drying apparatus is indicated as (1) as a whole and consists of a vacuum drying section (2) and a torsional vibration drive section (3).

The vacuum drying section (2) is connected to a column (6) erected on the base (3) via a vibration-proofing coil spring (TE) fixed to the bottom of the vacuum drying section (2).
) is supported. In addition, the vibration drive unit (3) is attached to a drive unit mounting plate (
4), and a pair of vibrating electric motors (5a) (5b) which are fixed to both sides of the drive unit mounting plate (4) at fixed angles in opposite directions with respect to the vertical axis. Vibration electric motor (
5a and 5b, as is well known, have substantially semicircular weights fixed to both ends of the rotating shaft of an induction motor, and when driven, a vibration force is generated by the centrifugal force of the semicircular weights. Furthermore, since the shaft is fixed at a fixed angle in the direction opposite to the vertical shaft, a torsional vibration force is generated around the vertical shaft. This allows the vacuum drying section (2) to torsionally vibrate.

Next, details of the vacuum drying section (2) will be explained.

In the vacuum drying section (2), a track having a substantially U-shaped cross section is wound spirally and fixed on the inner peripheral wall surface of the substantially cylindrical main body (9), and a track formed in the center is fixed. A cylindrical body (2) is disposed in the space and fixed to the bottom surface of the main body (9) by, for example, welding. An electric heater coil (6) is wound around the cylindrical body (2).

It is assumed that the coil (b) k is connected to a power source even though it is not shown. Further, the heating source is not only the coil (b), but also a heater continuously disposed on the bottom surface of the track (to).

A guide chute a for guiding the material to the lower side of the track is integrally fixed at the upper end of the track α constructed as described above, and at the lower end of the guide shade α. In order to stabilize the installation, it is supported by a post fixed to the bottom of the main body (9). or,
A supply and discharge opening -) is formed at the lower end of the main body (9),
A gate plate is fixed to this with Bordeaux via a sealing member, and materials are supplied and discharged from here. The upper opening of the main body (9) is covered with a circular lid (B) via a ring-shaped seal plate, and the outer peripheral edge of the lid is fixed to the main body (9) by a port (2). In this way, the inside of the main body (9) is kept in a sealed state, but the lid extension) is provided with a pair of viewing windows <16) 6'f), to which a transparent plastic plate is attached. This allows the flow and drying state of the material inside the main body (9) to be observed with the naked eye. In addition, a lid (B) K and two holes H are provided, and one hole (B) K is equipped with a vacuum gauge (to) to detect the degree of vacuum inside the main body (9). It has become. A flexible pipe (to) is connected to the other hole (g) K, and this is connected to a vacuum pump via a solenoid valve (not shown).

The interior of the main body (9) is evacuated by opening the vacuum pump and solenoid valve.

The vacuum drying apparatus according to the embodiment of the present invention is constructed as described above, and its functions will be explained below.

Although not shown, powder (coffee beans) to be dried is stored near the downstream end of the spiral track (7) of the main body (9). It is also assumed that the inside of the main body (9) is kept under a predetermined reduced pressure via a pipe (to) by a vacuum pump (not shown). A vacuum gauge (g) detects whether or not a predetermined reduced pressure is reached, and the pair of vibrating motors (5a) and (5b) are driven under the predetermined reduced pressure. A torsional vibration force is generated from this K, and the main body (9) supported by the coil spring (TE) causes a well-known torsional vibration, and the material to be dried moves along the spiral track. will be transferred. During this transfer, the material is heated by a coil CLI wound around the outer periphery of the cylinder (2) and a heater disposed on the bottom wall of the track αQ. In addition, the vacuum condition promotes the evaporation of moisture contained in the material, and the latent heat of evaporation is supplied by the coil (6) and heater, so that the material is heated and dried more efficiently. Further, the material is transported on the helical track aCt, and when it reaches its upper end Kt, it is returned through the guide chute α to the lower end of this track. The material then rises again on the spiral track due to the torsional vibration force and is dried by the drying effect of the vacuum and heating described above.

Therefore, the material is subjected to the drying action while forming a spiral track (
(to) upper and guide shaft, -) repeat up and down on Ql,
It circulates within the main body (9). At this time, since the material is transferred under reduced pressure, it is possible to increase the circulation speed in the atmosphere and perform heating and drying operations. That is, it is possible to perform efficient heating and drying actions.

After heating and drying for a predetermined time, the gate plate disposed below the main body (9) is removed by removing the Bordeaux. As a result, the material circulating in the body (9) is discharged to the outside of the body (9) through the supply and discharge opening (21) before being transferred upwards again along the track (to) IIc. Although not shown, a new material to be dried is supplied into the main body (9) while applying torsional vibration force to the supply/discharge opening @11 through the opening (IJ) through a shade. The material fed through the opening) moves up a helical track due to torsional vibrational forces and is finally filled into the body (9) to the required level. After being filled, the gate plate (b) is attached with Bordeaux, and as mentioned above, the material to be dried in the main body (9) is heated and dried while being heated and dried in the main body (9).
9) Circulate within.

The effects of the embodiments of the present invention have been explained above, and the effects will now be explained.

Since the material is transferred by vibration in a vacuum, the transfer speed is much higher than that by torsional vibration in the atmosphere, even with the same vibration force, as described above, and the drying efficiency is high. or,
Since heat drying is performed in a vacuum, combined with the above-mentioned improvement in transfer speed, it is possible to further improve drying efficiency compared to heat drying in the air.

Inside the vibrating motor, the bearings are coated with grease and the coils are coated with varnish, so when the vibrating motor heats up due to long-term operation, gas is released from inside the motor. Conventionally, the vibrating motor was installed in a vacuum, so this emitted gas deteriorates the degree of vacuum and is deposited on the material to be dried, possibly deteriorating the quality of the material or causing heating, drying. It was also supposed to reduce its effectiveness. However, according to this embodiment, the vibration electric motor (5
Since a) and (5b) are placed in the atmosphere and are disconnected from the materials to be heated and dried, they do not have the above-mentioned drawbacks.

FIGS. 5 and 6 show a circulating vacuum drying device (81) according to the second embodiment, which is also composed of a vacuum drying section and a torsional vibration drive section like the device of the first embodiment. Ru. The second embodiment differs from the first embodiment in that a heater is provided outside the vacuum chamber. Therefore, the configuration will be explained below. Also, parts corresponding to those in the first embodiment are designated by the same reference numerals, and detailed explanation thereof will be omitted.

In the vacuum drying unit, a track having a substantially U-shaped cross section is wound spirally and fixed on the inner pupil plane of a cylindrical main body (83), and the cylindrical body is placed in a space formed in the center. ■) is airtightly fixed to the bottom surface of the main body (goods), and the ring-shaped upper opening formed by the main body and the cylindrical body ■ is connected to the ring-shaped lid Gl ( 5), and is fixed to the main body by bolts (A) at its outer peripheral edge.
36a) is similarly fixed to the inner circumferential edge of the lid (...) via a seal plate with bolts. Therefore, a donut-shaped vacuum chamber (airtight chamber) is formed by the cylindrical wall of the main body, the cylindrical body, and the lid, and a spiral track is disposed within this donut-shaped vacuum chamber. A guide shoe (m) for guiding the material downward to the track (33) is integrally fixed to the upper end of the track (33). Further, a supply/discharge opening (21) is formed in the lower part of the main body (83) as in the first embodiment, and a gate plate is fixed to this with a bolt via a seal member. , Materials are supplied and discharged from here. In addition, the lid (2) is equipped with a peephole (α6), a vacuum gauge (g), and a vibrator (1) connected to a vacuum source via a solenoid valve, as in the first embodiment. A heating coil is wound around the outer periphery of the main body, and another heating coil is wound around the inner side of the cylindrical body between the coil supports. The rank part (40a) is fixed to the lid (35) with bolts.Therefore, the coil (341v'I) is disposed outside the vacuum chamber.

Next, the circulating vacuum dryer el configured as above
) and explain its functions and effects. Incidentally, since the action of circulating the material in the vacuum chamber is the same as in the first embodiment, the heating method will be explained. As in the first embodiment, the material is repeatedly raised and lowered on the spiral track (and the guide chute) while being subjected to the drying effect by vacuum conditions and heating.
It circulates within the main body (83). However, in the first embodiment, the heating coil and heater, which are the heating means, were installed in a vacuum chamber, so when the coil and heater were heated, gas was released from the insulating material of the electric wires that constituted them. The gas may deteriorate the quality of the material to be dried. In the second embodiment, since the coil serving as the heating means is disposed outside the vacuum chamber, only heat is applied purely to the material to be dried, without giving off gas. It is thus possible to obtain dried material of higher quality.

FIG. 7 shows the vacuum drying apparatus according to the third embodiment of the present invention. In the figure, parts corresponding to those in FIGS. is omitted.

That is, in the above embodiments, the main body is cylindrical, and a spiral track is wound around and fixed to the inner peripheral wall surface of the main body, but according to this embodiment, the cylindrical body is used as a sealed tank. Inside the elevator, only the spiral track portion of a so-called vibrating spiral elevator is placed under reduced pressure. The entire torsional vibration drive unit is placed in the atmosphere. A central cylindrical part fixed to the upper end of this torsional vibration drive part is located in a closed tank, and a spiral track is wound and fixed around the outer periphery of the central cylindrical part in a known manner. The upper end of the spiral track faces the lower end of the spiral track, that is, the entrance (52a). Therefore, the material fed to a certain level from the material supply/discharge port ascends the spiral track 64 by the drive of the torsional vibration drive unit, and passes from the upper end of the spiral track 64 through the guide chute (581) to the ascending port (52a). As in the above embodiment, vacuum drying can be carried out by repeating the circulation.
Since a heating coil is attached to the outer periphery of the heating coil, it is possible to prevent any adverse effects from this coil.

Other functions and effects are the same as those of the above-mentioned embodiment, so their explanation will be omitted.

Although each embodiment of the present invention has been described above, the present invention is of course not limited to these, and various modifications can be made based on the technical idea of the present invention.

For example, in the above embodiment, a pair of vibrating electric motors are used as the torsional vibrating drive unit, but the invention is not limited to this. For example, an electromagnet may be used to fix the vibrating motors on the base, and arrange the hermetically sealed tank and the base at equal angular intervals. A so-called electromagnetic type torsional vibration drive unit may be used by connecting with a leaf spring provided.

It is clear that other known torsional vibration drives may be used.

Furthermore, in the above embodiments, a heating source was provided inside and/or outside the tank to promote drying in a vacuum.
This may be omitted.

Furthermore, in the above embodiments, a common supply and discharge port was used to supply and discharge materials into the tank, but instead of this, separate supply and discharge ports may be provided. . Although this requires an extra sealing means (vacuum seal), compared to conventional equipment, the number of sealing means can be far reduced and the overall cost of the equipment can be reduced. can.

Furthermore, in the first and second embodiments described above, a spiral track is formed on the inner circumferential wall surface of the sealed tank, through which the material is raised, guided from the upper end to the lower end, and circulated.
In the example, only the spiral track wound around the central cylindrical part of a known vibrating spiral elevator was disposed inside the closed tank, and no track was formed on the inner circumferential wall of the closed tank. In the configuration shown in FIG. 7, a spiral track is further formed on the inner circumferential tube surface of the sealed tank in the same manner as in the first and second embodiments, and this track is also moved by a common torsional vibration drive unit. , the circulation efficiency may be further increased.

Furthermore, in the third embodiment, a so-called central cylindrical body β1) was used, and a spiral track was wound around the outer periphery of the central cylinder β1).
The upper end of this central cylinder (4) is made an opening, and the material transferred from the upper end of the spiral trough 6 is introduced into this opening and allowed to fall vertically to form an opening around the outer circumference of the cylinder (5N). It may also be guided to the lower end of a helical track wound around. That is, the guide shade in FIG. 7 can be omitted.

Further, in the above embodiments, the hermetic tank is made of an opaque body and has a viewing window formed in its lid, but the entire hermetic tank may be made of a transparent material so that it can be observed from the outside at any position. For example, it may be made of high heat resistant glass.

Furthermore, in the above embodiments, it was only explained that the patch 2 is dried by vacuum heating, and once the desired degree of dryness is obtained, it is discharged outward from the supply/discharge port. etc., it is necessary to cool it. For this purpose, a flexible pipe may be connected to the supply/discharge port and guided to the cooling device.

Further, in the above embodiments, an electric heater is used as a heating source, but far infrared rays may be used instead. In this case, for example, a far-infrared emitting material may be attached to the side wall of the spiral track, or a far-infrared emitting material may also be attached above the track. .

〔Effect of the invention〕

As described above, according to the vacuum drying apparatus of the present invention, the torsional vibration driving section is disposed in the atmosphere, so that the emitted gas does not have an adverse effect on the bulk material to be dried. , there is no need to reduce the degree of vacuum in the sealed tank, and because the bulk material is circulated on a spiral track only in the sealed tank, many vacuum seals are not required as in the past. The cost of the device can be significantly reduced without having to do so.

Moreover, the quality of the bulk material to be dried can be guaranteed. Furthermore, since the material is transported by vibration under reduced pressure, depending on the quality of the bulk material, the transport speed can be increased even further under the same torsional vibration conditions.

[Brief explanation of the drawing]

FIG. 1 is a side view of the vacuum drying apparatus according to the first embodiment of the present invention, FIG. 2 is a plan view of the same, and FIG. 3 is I-1 in FIG. 1.
4 is a sectional view taken along the line IV-■ in FIG. 3, FIG. 5 is a partially cutaway side view of the vacuum drying apparatus according to the second embodiment of the present invention, and FIG. Vl-V
A cross-sectional view in the I-line direction and FIG. 7 are a partially cutaway side view of a vacuum drying apparatus according to a third embodiment of the present invention. In addition, in the figure

Claims (3)

[Claims] (1) In a vacuum drying device in which bulk materials are transported by torsional vibration on a spiral track in a closed tank under reduced pressure and dried by circulation, the torsional vibration drive unit is placed in the atmosphere. A vacuum drying apparatus characterized in that the bulk material is circulated and dried on the spiral track only in the closed tank that receives the torsional vibration force of the torsional vibration drive section. (2) The sealed tank has a cylindrical shape, and the spiral track is wound around and fixed to the inner peripheral wall surface of the tank.
1) The vacuum drying device according to item 1). (3) The vacuum drying apparatus according to claim (1) or (2), wherein a heating source is provided inside and/or outside the closed tank.