JPH06262001A - Drum dryer - Google Patents

Abstract

PURPOSE:To easily perform the operation of a drum dryer by dispensing with the contact and separation operation of a scraper knife due to a worker by performing the contact and separation operation of the scraper knife with respect to a drum by an air cylinder. CONSTITUTION:When a cylinder rod advances or retreats by the driving of an air cylinder 32, a scraper main body is rotated and a scraper knife 37 comes into contact with the surface of a drum 21 or separates therefrom. The air supply system 40 for supplying air to the air cylinder 32 has a pressure reducing valve 41 having a relief mechanism built therein on a high pressure side, a pressure reducing valve 42 having a relief mechanism built therein on a low pressure side, an automatic opening and closing valve 43 on a high pressure side, an automatic opening and closing valve 44 on a low pressure side, a changeover solenoid valve 45 and the air tubes connecting those valves to the air cylinder 32. Since the pressure of the air supplied to the air cylinder 32 is constant because of this constitution, the contact pressure of the scraper knife 37 to the drum 21 can be always made constant and, by properly regulating air pressure, the contact pressure can properly be set and stable operation can be performed.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a drum dryer in which a liquid raw material is adhered to the surface of a rotating drum in a heated state to dry and solidify the solidified raw material, and the solidified raw material is scraped off by a scraper knife.

[0002]

2. Description of the Related Art The above-mentioned drum dryer is widely used for producing chemical products, chemicals, foods, dyes, etc. and can be classified into a single-drum type and a double-drum type. it can.

As shown in FIGS. 7 to 9, the double-drum type drum dryer has two drums (2) and (2).
Is rotatably arranged while maintaining a predetermined clearance, and a raw material supply mechanism (3) is provided corresponding to the upper feed part (3a) between the drums (2) and (2).

In addition, on both sides of the drums (2) and (2), the beam (4) is provided over the entire length of the drums (2) and (2).
(4) is provided and its beam (4) (4)
The shafts (6) and (6) are attached to the brackets via brackets (5).

A plurality of scraper bodies (7) are rotatably attached to the shaft (6). A scraper knife (8) is fixed to one side of each scraper body (7), and a lower end side of a spindle (9) is slidably attached to the other side along the axial direction. A plurality of spindle supports (10) are fixed to both sides of the beams (4) and (4) respectively corresponding to the spindles (9), and are provided on the outer periphery of the central portion of each spindle (9). The threaded part (9a)
It is screwed into each spindle support (10).

Spring holders (11) are fixed to the lower part of each spindle (9), and a spring (12) is interposed between each spring holder (11) and each scraper body (7). There is.

When the handle (14) attached to the upper end of the spindle (9) is rotated to move the spindle (9) upward, the washer (13) attached to the lower end of the spindle (9) is removed. The scraper body (7) is rotated by engaging with the scraper body (7),
The scraper knife (8) is adapted to move away from the surface of the drum (2) (2). Conversely, when the spindle (9) is moved downward by rotating the handle (12), the scraper body (7)
Is pushed in via a spring (12) and is rotated, so that the scraper knife (8) moves in a direction close to the surface of the drum (2) (2).

Further, with the scraper knife (8) in contact with the surfaces of the drums (2) and (2), the handle (1
When the spindle (9) is moved further downward by rotating 4), the spring (12) compresses and the pressure corresponding to the amount of compression, in other words, the pressure corresponding to the amount of rotation of the handle (14). The scraper knife (8) is in contact with the surface of the drum (2) (2).

When the drum dryer is to be fully operated from the stopped state, the scraper knife (8) is first detached from the surface of the drum (2) (2) and the drum (2) (2) is heated. At the same time, it is rotated in the arrow (P) direction.

Subsequently, after the drum temperature and the rotating state are stabilized, the drum (2) is passed through the raw material supply mechanism (3).
(2) The liquid raw material is supplied to the upper feed portion (3a), and the liquid raw material is evaporated and concentrated to be attached in a film form on the drum surface.

After that, the scraper knife (8) is brought into contact with the drum surface at a low pressure by operating the handle (14). By this low pressure contact, the scraper knife (8)
To the drum (2) (2) sufficiently, and then, again by operating the handle, scraper knife (8)
Contact the drum surface with high pressure to start full-scale operation.

In full-scale operation, the drum (2) (2)
The raw materials continuously adhering to the dryness solidify while the drums (2) and (2) rotate, and then are scraped off sequentially by the scraper knife (8), and the conveyor (1
5) It will be collected at a predetermined place through (15).

On the other hand, when stopping the operation of the drum dryer, the supply of raw materials is first stopped. And when the amount of raw material attached to the drum (2) (2) is decreasing,
The contact pressure of the scraper knife (8) on the drum surface is reduced, and after a predetermined time has passed, the scraper knife (8)
Is separated from the drum surface.

By the way, in such a drum dryer, the scraper knife (8) is generally made of metal, the cutting edge is hardened or the cemented carbide is welded, and the surface of the drum (2) is hard. It is chrome plated. In order to prevent frictional damage and the like due to contact between hard metals as described above, the scraper knife (8) contacts the drum (2) while the raw material that also acts as a lubricant is not attached to the drum (2). You need to prevent it. Therefore, the scraper knife (8) needs to be detached from the drum (2) except when the raw materials are being adhered. In other words, every time the apparatus is operated, the scraper knife (8) is brought into contact with or separated from the drum (2). Need to do.

When the scraper knife (8) is brought into contact with the drum (2), if the scraper knife (8) is immediately brought into contact with the drum (2) under a high pressure, the contact load is concentrated for a period of time and the life of the knife is shortened. Of the knife (8) or damage the drum (2), it is necessary to bring the knife (8) into contact with it at a predetermined low pressure to sufficiently adjust it, and then to contact it at a high pressure. Further, if the knife (8) is brought into contact with a low pressure during a full-scale operation, the raw material cannot be sufficiently scraped off the drum surface due to insufficient contact pressure. is there.

[0016]

As described above, in the drum dryer, the contact and separation operations of the knife (8) need to be frequently performed, and the operation is delicate, but the conventional drum dryer is The contact operation of the scraper knife (8) to the drum (2) is performed by the handle (14). Therefore, the contact pressure of the knife (8) varies depending on the individual difference of the operator, and it is difficult to always obtain a constant contact pressure, and it is difficult to operate the apparatus stably. Further, in order to obtain an appropriate contact pressure of the knife (8), it is often dependent on the experience and intuition of the person who operates the handle (14), and it is difficult to obtain an appropriate contact pressure.
The above-mentioned over-pressure contact or insufficient contact pressure is apt to occur, which may damage the drum (2) and the knife (8), and from this point also, it is difficult to perform stable device operation. There was a problem.

Further, since the rotation operation of the handle (14) requires a great amount of labor, there is a problem that the operation of contacting and separating the knife (8) is complicated.

Moreover, the scraper knife (8) arranged over the entire length of the drum (2) is often of a split type because it has problems such as thermal expansion of the knife. In that case, eight knives are used for one drum, and double knives are doubled with 16 knives. Therefore, these many knives need to be brought in and out one by one by the complicated handle operation as described above, and it is much desired from the past to improve the operability at the time of the knife coming and going operation. It is a thing.

The drum dryer having the structure in which the knife (8) is brought into contact with the drum (2) in three steps before the full-scale operation has been described above. In a dryer having a structure for contacting the drum, that is, in a drum dryer having a structure in which the knife is brought into contact with the drum from the knife disengaged state and full-scale operation is immediately started in that state, the problem of the contact pressure described above, The problem of operability at the time of contacting / separating operation naturally occurs.

A first object of the present invention is to solve the above-mentioned problems of the prior art, to make the scraper knife contact the drum at a proper and constant pressure at all times, and to perform stable operation of the apparatus. It is an object of the present invention to provide a drum dryer that can easily perform a contact / separation operation with respect to a drum of a scraper knife.

[0021] A second object of the present invention is to provide a drum dryer which can easily carry out the contacting / separating operation with respect to the drum of the scraper knife after achieving the above-mentioned first object.

A third object of the present invention is, in addition to achieving the first object, a drum dryer which does not require a worker to move the scraper knife in and out of operation and can easily operate the apparatus. Is to provide.

[0023]

In order to achieve the above-mentioned first object, the drum dryer of the first invention rotates a heated drum and causes a liquid material to adhere to the surface of the drum to dry and solidify. A drum dryer in which the solidified raw material is scraped off by a scraper knife in contact with the surface of the drum, and a fluid pressure cylinder for bringing the scraper knife into and out of contact with the surface of the drum, and the fluid pressure cylinder. A fluid supply system for supplying fluid therein, and a knife disengagement state defined by a state in which the scraper knife is disengaged from the surface of the drum by a fluid supply operation of the fluid supply system, State of knife contact defined by the state of the scraper knife in contact with the surface of the drum, It is an gist to become set freely configured in.

In order to achieve the second object, the drum dryer of the second invention in the first invention is set to a knife disengagement state and a knife contact state in accordance with a command from an operator. Thus, the gist is that the control means for performing the fluid supply operation of the fluid supply system is provided.

In order to achieve the above-mentioned third object, the drum dryer according to the third aspect of the present invention is such that, in the first aspect of the present invention, there is a raw material non-adhesion state defined by the state in which no raw material is attached to the surface of the drum. , A raw material state detecting means for directly or indirectly detecting two states of a raw material deposition initial state defined by a state in which the raw material is deposited on the surface of the drum, and an output signal from the raw material state detecting means. And a control means for performing a fluid supply operation of the fluid supply system such that the knife is detached when the raw material is not attached and the knife is contacted when the raw material is attached. , Is provided as a gist.

[0026]

In the drum dryer of the first invention, since the scraper knife is brought into contact with and separated from the drum by the fluid pressure cylinder, the fluid pressure supplied to the cylinder is always kept constant. The contact pressure of the knife can be obtained, and the contact pressure of the knife can be set to an appropriate value by appropriately adjusting the fluid pressure supplied to the cylinder. Moreover, even when a large number of scraper knives are provided, if fluid is supplied from the same fluid supply system to the fluid pressure cylinders for contacting and separating the knives, Fluid pressures that are the same as each other are obtained, and the contact pressure does not vary from knife to knife.

Further, the knife removing operation can be easily performed only by performing the fluid supply operation of the fluid supply system for supplying the fluid to the cylinder.

In the drum dryer according to the second aspect of the present invention, since the control means for performing the supply operation of the fluid supply system based on the instruction from the operator is provided, the above-mentioned instruction is controlled by one-touch operation or the like. If it is configured so that it can be given to
It can be set to a knife detached state and a knife contact state.

In the drum dryer according to the third aspect of the invention, the raw material state detecting means for detecting the state of attachment of the raw material to the drum, and the fluid supply operation of the fluid supply system based on the signal from the detecting means. Since the control means is provided, the knife disengagement state and the knife contact state are automatically set depending on the raw material state.

[0030]

1 is a schematic sectional view showing a drum dryer according to an embodiment of the present invention, and FIG. 2 is a side view of a main portion showing the drum dryer.

As shown in both figures, two drums (21) and (21) are rotatably attached to the apparatus main body (20) while maintaining a predetermined clearance.
The upper cover (22) is attached so as to cover the feed portion (22b) between the drums (21) and (21) from above.

An exhaust port (22a) is formed at the upper end of the upper cover (22), and this exhaust port (22)
The gas discharge pipe (23) is connected to a). Inside the gas exhaust pipe (23), a temperature sensor (24) for detecting the temperature of the exhaust gas passing through the exhaust pipe (23) is attached.

Further, a raw material supply pipe of the raw material supply mechanism (25) is penetrated through the upper part of the upper cover (22), and the tip of this supply pipe is arranged above the drums (21) (21). It is arranged so as to face the feed portion (22b).

Above the drums (21) (21), the beam (27) is provided over the entire length of the drums (21) (21).
(27) is provided and this beam (27)
A plurality of scraper mechanisms (30) described later are attached to (27) at intervals along the rotation axis direction of the drums (21) and (21).

Further, side covers (28) and (28) are attached to the apparatus main body (20) so as to cover both drums (21) and (21) from both sides, and inside the side covers (28) and (28). A screw type conveyor (29) (29) for transporting the scraped solidified raw material is arranged at a position below.

As shown in FIGS. 3 and 4, in the scraper mechanism (30), the lower surface of the beam (27) is
A shaft (34) is supported via a bracket (35), and a plurality of scraper main bodies (36) are rotatably attached to the shaft (34).

Corresponding to each scraper body (36), a plurality of air cylinders (32) are rotatably attached to the outer surface of the beam (27) via cylinder brackets (31) in a downward direction. At the same time, a spindle (33) is connected to the lower end of the rod of each air cylinder (32).

The lower end of each spindle (33) and one piece of each scraper body (36) are rotatably attached to each other, and a scraper knife (37) is attached to the other piece of each scraper body (36). Each is fixed.

Then, when the cylinder rod is advanced and retracted by driving the air cylinder (32), the scraper body (36) rotates and the scraper knife (37) moves to the position shown in FIG.
As shown by the solid and imaginary lines of FIG.

Returning to FIG. 1, the air cylinder (32)
An air supply system (40) for supplying air to the high pressure side pressure reducing valve (41) with a relief mechanism, a low pressure side pressure reducing valve (42) also with a relief mechanism, a high pressure side automatic opening / closing valve (43), a low pressure side. Side automatic opening / closing valve (44), switching solenoid valve (45), these valves and the air cylinder (3
It has an air tube etc. for connecting 2).

The high pressure side pressure reducing valve (41) can output the air supplied from the air supply means while maintaining a certain high pressure, as indicated by the arrow (A). The generated high-pressure air is supplied to the high-pressure side automatic open / close valve (4
The solenoid valve (45) side can be supplied / stopped by opening / closing 3).

The low pressure side pressure reducing valve (42) is capable of outputting the air A supplied from the air supply means while keeping it at a certain low pressure, and outputs the low pressure air thus output to the low pressure side. The automatic opening / closing valve (44) can be opened / closed to supply / stop the switching solenoid valve (45).

The switching solenoid valve (45) is capable of supplying, stopping, switching, and the like of air, and the cylinder rod of the air cylinder (32) is advanced and retracted by such an operation.

On the other hand, the drum dryer is provided with a control means (50), and the control means (50) is provided.
And the temperature sensor (24) and the automatic opening / closing valve (43)
(44) and the switching solenoid valve (45) are connected via a signal line. Then, in this drum dryer, the control means (50), based on the output signal from the temperature sensor (24), the automatic opening / closing valves (43) (44).
The opening / closing operation and the switching solenoid valve (45) are operated to perform the operation described in detail later.

Next, the operation of the drum dryer from the stopped state to the full-scale operation will be described with reference to the flowchart of FIG.

In the operation stopped state, the rods of the air cylinders (32) are retracted, and the scraper knives (37) are separated from the drums (21) and (21). Further, the high pressure side automatic opening / closing valve (43) is closed, the low pressure side automatic opening / closing valve (44) is opened, and low pressure air is supplied to the switching electromagnetic valve (45).

From this state, as shown in step (S1), steam is supplied into the drums (21) and (21) to heat the drums (21) and (21), and at the same time, the drum (2)
1) Rotate (21).

Subsequently, after the drum temperature, the rotation state, etc. have stabilized, as shown in step (S2), the liquid is fed from the raw material supply mechanism (26) to the feed section (22b) above the drums (21) and (21). Supply raw materials.

The liquid raw material supplied to the feed section (22b) is evaporated and concentrated and adheres to the drum surface in a film form. On the other hand, vaporization is caused by evaporation, and as the amount of vapor is increased, gas is generated. The temperature of the exhaust gas discharged through the discharge pipe (23) gradually rises.

Then, as shown in step (S3),
When the temperature of the exhaust gas reaches or exceeds the predetermined temperature, the temperature sensor (24) outputs a signal to that effect to the control means (50). The control means (50) receiving this output signal,
As shown in step (S4), the switching solenoid valve (45) is switched, the rods of the air cylinders (32) are advanced, and the scraper knives (37) are moved to the drum (2).
Contact 1).

In this case, the switching solenoid valve (4
Since the air supplied from 5) is of low pressure,
Each scraper knife (37) will contact the drum (21) at low pressure.

Next, as shown in step (S5), the control means (50) uses the built-in timer to determine the elapsed time from the time point (step S3) at which the exhaust gas temperature becomes equal to or higher than a predetermined temperature. After the measurement and a predetermined time has elapsed, the control means (50) operates to open the high pressure side automatic opening / closing valve (43) and close the low pressure side automatic opening / closing valve (44). Thereby, as shown in step (S6), the air supplied to each air cylinder (32) is switched from the low pressure to the high pressure, and the contact pressure of each scraper knife (37) to the drum (21) is changed. Will be switched from low pressure to high pressure.

After that, full-scale operation is performed in this drum dryer.

That is, the raw material continuously adhering to the surfaces of the drums (21) and (21) is dried and solidified while the drums (21) and (21) rotate, and then scraped off sequentially by the scraper knife (37). The conveyor (2
9) It will be collected at a predetermined place via (29).

Here, the relationship between the exhaust gas temperature and the raw material deposited on the drum (21) will be described in order to prove the reliability of the control operation. The exhaust gas temperature is correlated with the amount of vapor generated, and the amount of vapor generated is
There is a correlation with the amount of the raw material deposited on 1). Therefore, the exhaust gas temperature when the raw material adheres to the state where the scraper knife (37) is brought into low-pressure contact is experimentally or empirically obtained in advance, and that temperature is used as the predetermined temperature in the step (S3). Then, by performing the control operation described above, the knife (37) can be operated at an appropriate timing.
Can be brought into contact with each other at a low pressure, and the knife contact operation can be performed without any trouble.

Further, the time from the low pressure contact of the knife (37) to the high pressure contact thereof becomes a constant value depending on the device, and this time is experimentally or empirically determined. By using it as the predetermined time of S5), the knife (3
7) can be switched from low pressure contact to high pressure contact,
The contact pressure switching operation is performed without any trouble.

Next, the operation of the drum dryer from full-scale operation to stop of operation will be described with reference to the flowchart of FIG.

During the full-scale operation, the rods of the air cylinders (32) are advanced and the scraper knives (37) are in contact with the drum (21). At this time, high pressure air is being supplied to each air cylinder (32), that is, the high pressure side automatic on-off valve (43) is open, the low pressure side automatic on-off valve (44) is closed, and the knife ( 37) is in contact with the drum (21) under high pressure.

From this state, the supply of the raw material is stopped as shown in step (S11). As a result, the raw materials on the feed section (22b) and the drum (21) are reduced and the vapor is also reduced, and the temperature of the exhaust gas is gradually reduced with the decrease.

Then, as shown in step (S12),
When the exhaust gas temperature reaches the predetermined temperature or lower, the temperature sensor (24) outputs a signal to that effect to the control means (50). Upon receiving this signal, the control means (50) closes the high pressure side automatic open / close valve (43) and at the same time opens the low pressure side automatic open / close valve (44). Thereby, as shown in step (S13), the air supplied to each air cylinder (32) is switched from the high pressure to the low pressure, and the drum (2) of each scraper knife (37) is changed.
The contact pressure to 1) will be switched from high pressure to low pressure.

Next, as shown in step (S14),
The control means (50) measures an elapsed time from the time when the exhaust gas temperature becomes equal to or lower than a predetermined temperature (step S12),
When a predetermined time has elapsed, as shown in step (S15), the switching solenoid valve (45) is switched and the rods of the air cylinders (32) are retracted to move the scraper knives (37) to the drum (21). ) To leave.

Next, as shown in step (S16),
The rotation of the drum (21) is stopped, and the operation of stopping the operation of the apparatus is completed.

Even when the operation of the apparatus is stopped in this way, the contact pressure switching operation of the knife (37) and the detaching operation of the knife (37) are performed at appropriate timings for the same reason as above. It will be.

As described above, according to this drum dryer, since the scraper knife (37) is brought into contact with and separated from the drum (21) by the air cylinder (32), the air is supplied to the cylinder (32). The air pressure is constant at both the high pressure contact and the low pressure contact of the knife, and a constant contact pressure can be obtained at both the high pressure and the low pressure, and the air pressure is supplied to the cylinder (32). By appropriately adjusting the air pressure to be used, the contact pressure of the knife can be set to an appropriate value, and stable device operation can be performed.

Moreover, a large number of cylinders (3
In 2), since air is supplied from the same air supply system (40), the same and appropriate air pressure can be obtained between the cylinders, and each knife (37) There is no occurrence of variation in contact pressure, and stable device operation can be performed without any problems.

Further, since the control means (50) for switching the air supply system (40) is provided on the basis of the temperature of the exhaust gas and the elapsed time, the knife (37) is brought into contact with or separated from the air supply system (40). The contact pressure switching operation is automatically performed. Therefore, the operator does not need to perform these operations, and the operation of the device can be easily performed.

Since the timing of the contact / separation operation of the knife (37) can be finely adjusted by changing the temperature setting of the temperature sensor (24), the timing of the contact / separation operation can be set to an appropriate one. . In addition, a knife (3
The timing of the contact pressure switching operation of 7) can also be set to an appropriate one by changing the setting of the predetermined time, and the device operation can be favorably performed.

Further, by adopting the structure for automatically performing the contact / separation operation and the contact pressure switching operation of the knife (37) as in the present invention, the series of operations from the start to the end of the operation of the drum dryer is fully automated. This makes it possible to reduce the labor force of workers and improve work efficiency.

The present invention is not limited to the above-mentioned embodiment, but various design changes and the like are possible.

For example, when full-scale operation is performed from the stopped state of the apparatus, the contact operation of the knife (37) and the switching operation from the low pressure contact to the high pressure contact are performed based on the elapsed time from the time when the raw material is supplied. Alternatively, the switching operation from the low pressure contact to the high pressure contact may be performed based on the temperature of the exhaust gas. Further, when the apparatus is stopped from full-scale operation, the switching operation from the high pressure contact to the low pressure contact may be performed based on the elapsed time from the time when the supply of the raw material is stopped. The knife removal operation may be performed on the basis of the temperature. In short, the effect of the present invention can be obtained by adopting a means capable of directly or indirectly detecting the adhered state of the raw material.

In the above embodiment, the air cylinder is used as the fluid pressure cylinder, but the fluid pressure cylinder is not limited to this, and other fluid pressure cylinders such as a hydraulic cylinder may be used.

In the above embodiment, the case where the present invention is applied to the double-drum type drum dryer has been described. However, the present invention is not limited to this, and the present invention can also be applied to the single-drum type.

By the way, in the above embodiment, the knife (3
Although the contact / separation operation and the contact pressure switching operation of 7) are automatically performed, it is also possible to configure these operations to be performed by one-touch operation. For example, the operation unit of the dryer device is provided with an input means for inputting an operator's command, and a worker's knife contact / separation command and contact pressure switching command input to the control means via the input means are used. Based on this, the control means may be configured to perform switching adjustment of the air supply system to perform knife contact / separation operation or contact pressure switching operation.

With such a structure, the knife contact / separation operation and the contact pressure switching operation can be easily performed by one-touch operation.

[0075]

As described above, according to the drum dryer of the first invention, since the scraper knife is brought into contact with and separated from the drum by the fluid pressure cylinder, the fluid pressure supplied to the cylinder is reduced. By making it constant, a constant contact pressure can be obtained at all times, and by appropriately adjusting the fluid pressure supplied to the cylinder, the contact pressure of the knife can be set to an appropriate value, which is stable. The device can be operated. Moreover, even when a large number of scraper knives are provided, if fluid is supplied from the same fluid supply system to the fluid pressure cylinders for contacting and separating the knives, The same and appropriate fluid pressures are mutually obtained, and the contact pressure does not vary among the knives, and stable operation of the device can be performed without any trouble. Further, the first effect is obtained in that the knife detaching operation can be easily performed only by performing the fluid supply operation of the fluid supply system.

According to the drum dryer of the second invention,
In the first aspect of the invention, the control means for performing the fluid supply operation of the fluid supply system based on the command from the operator is provided. Therefore, in addition to the first effect, the one-touch operation or the like can be performed. If it is configured so that commands can be given to the control means, it is possible to perform a one-touch operation, etc.
It is possible to set the knife detaching state and the knife contacting state, and it is possible to obtain the second effect that the knife contacting and detaching operation can be performed more easily.

According to the drum dryer of the third invention,
In the first aspect of the present invention, there are provided a raw material state detection means for detecting the state of attachment of the raw material to the drum, and a control means for performing a fluid supply operation of the fluid supply system based on a signal from the detection means. Therefore, in addition to the above first effect, the knife detachment state and the knife contact state are automatically set according to the raw material state, so that the operator does not need to perform the knife contacting / separating operation. The third effect is that the device can be operated easily.

[Brief description of drawings]

FIG. 1 is a schematic sectional view showing a drum dryer according to an embodiment of the present invention.

FIG. 2 is a side view of the essential parts showing the drum dryer of the embodiment.

FIG. 3 is a partially cutaway side view showing the scraper mechanism of the drum dryer of the embodiment.

FIG. 4 is a front view showing the scraper mechanism of the embodiment.

FIG. 5 is a flowchart showing an operation from a stopped state to a full-scale operation of the drum dryer of the embodiment.

FIG. 6 is a flowchart showing an operation from a full-scale operation of the drum dryer of the embodiment to a stopped state.

FIG. 7 is a schematic sectional view showing a conventional drum dryer.

FIG. 8 is a partially cutaway side view showing a scraper mechanism of a conventional drum dryer.

FIG. 9 is a side view of an essential part showing a conventional drum dryer.

[Explanation of symbols]

 21 ... Drum 32 ... Air cylinder 37 ... Scraper knife 40 ... Air supply system 50 ... Control means

Claims (3)

[Claims] 1. While rotating a heated drum,
Liquid material is attached to the surface of the drum to dry and solidify,
A drum dryer in which the solidified raw material is scraped off by a scraper knife in contact with the surface of the drum, a fluid pressure cylinder for bringing the scraper knife into and out of contact with the surface of the drum, and A fluid supply system for supplying a fluid to the blade, and a knife disengagement state defined by a state in which the scraper knife is disengaged from the surface of the drum by a fluid supply operation of the fluid supply system; A drum dryer, which is configured to be freely set between a knife contact state defined by a state where a knife is in contact with the surface of the drum, and a knife contact state. 2. A control means for performing a fluid supply operation of the fluid supply system is provided so that the knife detachment state and the knife contact state are respectively set according to an instruction from an operator. ) Described in the drum dryer. 3. A raw material non-adhered state defined by a state in which no raw material is attached to the surface of the drum, and a raw material adhering initial state defined by a state in which the raw material is attached to the surface of the drum. Based on the output signal from the raw material state detection means for directly or indirectly detecting one of the two states and the raw material state detection means, when the raw material is not attached, the knife is detached and the raw material is attached. The drum dryer according to claim 1, further comprising: a control unit that performs a fluid supply operation of the fluid supply system so as to be set in a knife contact state at each time.