JP6287643B2 - Batch type drying furnace - Google Patents

Description

  The present invention relates to a batch type drying furnace in which, for example, a coated body of a vehicle is contained in a sealed drying chamber for a required time and dried.

For example, as shown in FIGS. 9 and 10, as a batch-type drying furnace 100 in which a coating completion body 101 of a vehicle is accommodated for a required time in a sealed drying chamber 102 and dried, a coating completion body 101 is placed. The transported carriage 103 is carried into the drying chamber 102 from the front-rear direction of the vehicle (in the direction of arrow F), and hot air is passed for a required time with the open / close doors of the inlet 104 and the outlet 105 provided at the front and rear of the drying chamber being closed. There is known a flat furnace type drying furnace in which the coating body 101 is dried by discharging 106 from the side duct 107 into the drying chamber 102 and exhausting it from the ceiling duct 108 to the exhaust pipe 109 outside the drying chamber 102. Yes. The flat furnace type drying furnace 100 is a drying furnace suitable for a small-volume production vehicle because the apparatus is compact and equipment costs can be reduced.
However, in the above flat furnace type drying furnace 100, every time the coating completion body 101 is carried into and out of the drying chamber 102, heat escapes from the inlet 104 and the outlet 105 provided in the front and rear of the drying chamber 102 to the outside.・ It took a long time to raise the temperature required for baking, and there was a problem that we had to use wasted energy.
Further, as shown in FIGS. 9 and 11, in the open furnace type drying furnace 100, it has been found through investigation that the temperature rise of the coating body 101 varies depending on the part. For example, the hood part a and the back door part b heat up relatively quickly, while the B pillar part c and the rocker part d heat up relatively slowly. For this reason, there is a problem that the heating time of the entire furnace becomes longer than necessary because it is dragged to the part with the slowest temperature rise (for example, the rocker part d), and the productivity of the drying furnace 100 is lowered.

For such a problem, for example, in Patent Document 1, a heat treatment furnace fixed above the floor surface and provided with an opening in the floor portion, the first position set just below the opening portion on the floor surface. And a movable table that moves between a second position spaced apart on the floor, and a lifting drive means that can put the workpiece on the workpiece support table mounted on the movable table into the heat treatment furnace from the opening. A heat treatment furnace is disclosed.
Further, for example, in Patent Document 2, in a drying furnace for drying an object to be dried with hot air, a part of the object to be dried that has a heat capacity larger than that of another part and is difficult to warm is added to the part that is difficult to warm by applying radiant heat. There is disclosed a drying furnace provided with heating means (for example, a near infrared lamp) for heating so that the temperature approximates the temperature of the other part.

JP 2008-229467 A JP 2011-245412 A

However, the heat treatment furnace described in Patent Document 1 has the following problems.
That is, the heat treatment furnace includes a movable table that moves between a first position set just below the opening on the floor surface and a second position spaced apart on the floor surface, and a workpiece mounted on the movable table. Elevating and lowering drive means that can put the work on the support base into the heat treatment furnace through the opening, so that the work can be loaded into the furnace, and the work loading / unloading port for taking out the work from the furnace. It is necessary to always go through the second position. For this reason, the time for taking out the workpiece after the heat treatment at the second position from the workpiece support and placing the workpiece before the heat treatment on the workpiece support (work changing time) is added to the cycle time of the heat treatment furnace. The workpiece transfer time includes the waiting time of the workpiece transfer device. Therefore, a lot of time is spent on the movement time of the work before and after the heat treatment. As a result, there is a problem that the cycle time of the heat treatment furnace becomes long and the productivity is greatly reduced.
Moreover, since the opening part of the said heat processing furnace is a structure covered with a workpiece | work support stand, it will be in the open | released state at least during the reciprocation time of a workpiece | work support stand. Therefore, although it is below the furnace, hot air escapes to the outside of the furnace, and the problem of wasted energy remains. In addition, since the work support base, the movable base, the lifting drive means, etc. are arranged on the floor surface, there is a problem that the heat treatment furnace becomes large as a whole, and an increase in equipment cost is inevitable.

Moreover, the drying furnace described in Patent Document 2 has the following problems.
That is, the drying furnace is provided with heating means (for example, a near infrared lamp) for heating so that the temperature of the part that is difficult to warm by applying radiant heat approximates the temperature of the other part. Although the temperature of the part where the applied light beam (for example, near infrared rays) hits can be raised, the part that is blocked by that part and does not receive the light beam that applies radiant heat (for example, near infrared ray) is a part that is difficult to warm up. However, the effect of temperature rise cannot be expected. Therefore, in the same workpiece (for example, side sill or rocker panel), a temperature difference is likely to occur between the outside of the workpiece that is exposed to the radiant heat beam and the inner side of the workpiece that is not exposed to the radiant heat beam. There was a problem that heat distortion occurred in the workpiece.

  The present invention has been made to solve the above-described problems, and has an object to provide a batch-type drying furnace that has high productivity as a drying furnace, can save energy, and can uniformly heat a workpiece. And

In order to solve the above-described problems, a batch-type drying furnace according to the present invention has the following configuration.
(1) A work is accommodated for a required time in a hermetically sealed drying chamber having a blower duct for blowing hot air into the room and an exhaust duct for discharging hot air to the outside, and the hot air is circulated in the drying room to circulate the work. A batch drying oven for drying,
The drying chamber is disposed above a workpiece conveyance path through which the workpiece moves, and the floor surface of the drying chamber is formed with an underfloor opening through which the workpiece can pass, and the underfloor opening is It is opened and closed by a lifting platform that carries a workpiece and moves up and down from the workpiece conveyance path to the floor of the drying chamber,
In the drying chamber, the air duct and the exhaust duct are arranged so that the air blowing direction of the air duct and the air discharging direction of the air exhaust duct intersect in the drying chamber. To do.

  In the present invention, the drying chamber is disposed above the workpiece conveyance path through which the workpiece moves, and the floor surface of the drying chamber is formed with an underfloor opening through which the workpiece can pass, and the underfloor opening is Since it is opened and closed by a lifting platform that raises and lowers the workpiece from the workpiece conveyance path to the floor of the drying chamber, each conveyance carriage loaded with the workpiece on the workpiece conveyance path is mounted on the lifting platform and loaded into the drying chamber. The drying chamber can be closed by a lifting platform. Therefore, it is possible to greatly reduce the time for moving the workpiece into the drying chamber and the opening time of the drying chamber. Therefore, the cycle time of the drying furnace can be shortened and productivity can be improved. Moreover, the time for hot air to escape from the underfloor opening to the outside of the furnace can be shortened, and wasteful use of energy can be reduced.

In addition, since the ventilation duct and the exhaust duct are arranged in the drying chamber so that the blowing direction of the ventilation duct and the exhausting direction of the exhaust duct intersect in the drying chamber, hot air is blown to the entire drying chamber. It can be circulated. Therefore, even if there is a part where the temperature of the workpiece is slow to rise somewhere in the drying chamber, the hot air can be circulated and heated also to the part where the temperature of the workpiece is slowly raised. Therefore, the heating time of the entire workpiece can be shortened without being dragged to a portion where the temperature rise is slow. As a result, the cycle time of the drying furnace can be shortened, the thermal energy can be efficiently utilized, and the temperature rise difference due to the part of the workpiece W can be reduced.
Therefore, according to the present invention, it is possible to provide a batch-type drying furnace that has high productivity as a drying furnace, can save energy, and can uniformly heat a workpiece.

  In addition, it is preferable that a conveyance trolley passes on an elevator stand by one way. That is, it is preferable that the conveyance carriage on which the workpiece before drying is placed enter from the entrance of the drying furnace, and the conveyance carriage on which the workpiece after drying is placed exits from the outlet of the drying furnace. In this case, the conveyance carriage can be made to enter from the entrance of the drying furnace, and at the same time, the conveyance carriage can be made to exit from the exit of the drying furnace. As a result, it is possible to shorten the time for replacing the workpiece into the drying furnace, which is convenient for shortening the cycle time of the drying furnace.

(2) In the batch-type drying furnace described in (1),
The blower duct includes side ducts disposed on both left and right wall surfaces of the drying chamber, and the exhaust duct includes a front duct and a rear wall surface disposed on the front wall surface of the drying chamber. And a rear duct disposed on the front side.

  In the present invention, the blower duct includes a side duct disposed on the left and right wall surface of the drying chamber, and the exhaust duct includes a front duct and a rear wall surface disposed on the front wall surface of the drying chamber. So that hot air flows from the side duct to the center of the drying chamber, and the hot air that flows to the center of the drying chamber divides in the front-rear direction and flows to the front of the drying chamber and the rear of the drying chamber. Can be circulated. For this reason, hot air having a relatively high temperature is supplied to the central part of the drying chamber where the part having a large heat capacity in the workpiece is arranged, compared to the front part and the rear part of the drying room where the part having a small heat capacity is arranged. Will be.

In particular, when the workpiece is a coated body, the hot air in the drying chamber is easily heated to other parts (for example, the B pillar part or the rocker panel part) (for example, the hood part or the back door). Part), the heating time can be shortened and the uniform heating of the entire workpiece can be promoted simultaneously.
Therefore, according to the present invention, the hot air having a relatively high temperature is preferentially supplied to the central portion of the drying chamber, whereby the productivity as the drying furnace is further increased, energy saving is possible, and the work is further improved. Uniform heating is possible.

  In addition, it is preferable to discharge hot air from the front lower duct adjacent to the floor surface of the drying chamber and the rear duct to the outside of the room. Since cold air tends to accumulate near the floor of the drying room, it is possible to discharge the cold air together with the front lower duct and the rear duct adjacent to the floor of the drying room. is there.

(3) In the batch-type drying furnace described in (2),
The flow rate of the hot air blown into the drying chamber from the center portion in the front-rear direction of the side duct is larger than the flow rate of hot air blown into the drying chamber from the front portion and the rear portion in the front-rear direction of the side duct. To do.

In the present invention, the flow rate of hot air blown into the drying chamber from the center portion in the front-rear direction of the side duct is larger than the flow rate of hot air blown into the drying chamber from the front portion and the rear portion of the side duct in the front-rear direction. Can flow more from the side duct to the center of the drying chamber, and the hot air flowing more to the center of the drying chamber can be divided in the front-rear direction and flow to the front of the drying chamber and the rear of the drying chamber. Therefore, hot air can be circulated more powerfully throughout the drying chamber.
Therefore, according to this invention, the workpiece | work in a drying chamber can be heated more rapidly and uniformly.

(4) In the batch-type drying furnace described in any one of (1) to (3),
A heat storage member is mounted on the lifting platform.

In the present invention, since the heat storage member is mounted on the lifting platform, the hot air circulating near the floor in the drying chamber can be heated by the heat energy stored in the heat storage member.
Therefore, according to the present invention, energy saving in the drying furnace can be further promoted.

  ADVANTAGE OF THE INVENTION According to this invention, the productivity as a drying furnace is high, energy saving is possible, and the batch type drying furnace which can heat a workpiece | work uniformly can be provided.

It is sectional drawing of the front-back direction of the batch type drying furnace which concerns on embodiment of this invention. It is a left-right direction sectional view of the drying furnace shown in FIG. It is a schematic diagram showing the flow volume and circulation state of the hot air which flows through the drying chamber of the AA cross section shown in FIG. It is a schematic diagram showing the flow volume and circulating state of the hot air which flows through the drying chamber of the BB cross section shown in FIG. It is a piping system diagram of the drying furnace shown in FIG. It is typical sectional drawing showing the raising / lowering apparatus of the drying furnace shown in FIG. It is a top view of the raising / lowering stand shown in FIG. It is a side view explaining the carrying in / out method of the workpiece | work to the drying furnace shown in FIG. It is sectional drawing of the front-back direction of the conventional batch type drying furnace. It is a left-right direction sectional view of the conventional batch type drying furnace. It is a graph showing the temperature rising transition condition for every part of the workpiece | work in the batch type drying furnace shown in FIG.

  Next, a batch-type drying furnace according to an embodiment of the present invention will be described in detail with reference to the drawings. First, the overall structure of the drying furnace according to the present embodiment will be described. Thereafter, the flow rate and circulation state of the hot air flowing through the drying chamber will be described, and a piping system diagram of the drying furnace will be described. Next, the lifting platform and the lifting device will be described, and the work loading / unloading method will be described. Finally, the operational effects of the batch-type drying furnace according to this embodiment will be described.

<Overall structure of drying oven>
First, the entire structure of the drying furnace according to the present embodiment will be described with reference to FIGS. 1 and 2. FIG. 1 is a cross-sectional view in the front-rear direction of a batch-type drying furnace according to an embodiment of the present invention. FIG. 2 shows a cross-sectional view in the left-right direction of the drying furnace shown in FIG.

  As shown in FIGS. 1 and 2, a batch-type drying furnace 10 according to this embodiment includes a drying chamber 2 installed above a work transfer path 1 formed on a factory floor. Immediately below the drying chamber 2, a standby chamber 13 is formed in which the transport carriage 11 on which the workpiece W is placed waits. The waiting room 13 is surrounded by a heat insulating wall plate except for the inlet (IN) and the outlet (OUT). The opening areas of the entrance (IN) and the exit (OUT) are preferably set to a minimum size that allows the transport carriage 11 on which the workpiece W is placed to pass. This is because the release of thermal energy from the drying chamber 2 can be reduced as much as possible.

  In the drying chamber 2, a substantially rectangular space that can accommodate the transport carriage 11 on which the workpiece W is placed is formed. On the floor surface 261 of the drying chamber 2, a substantially rectangular underfloor opening 21 is formed. The underfloor opening 21 is opened and closed by a lift 26 that moves up and down in the vertical direction (in the direction of arrow L) from the work transfer path 1 to the floor surface 261 of the drying chamber 2. The transport carriage 11 is mounted on a lifting platform 26 that is lowered onto the work transport path 1 and is put into the drying chamber 2 through the underfloor opening 21. The workpiece W is a completely coated body of the vehicle and is placed on the transport carriage 11 with wheels. A hood portion (front side) of the vehicle is disposed at the front portion of the drying chamber, and a back door portion (rear side) of the vehicle is disposed at the rear portion of the drying chamber.

In the drying chamber 2, air ducts 22 and 24 that blow the hot air 3 into the room and air exhaust ducts 23 and 242 that exhaust the hot air 3 to the outside are formed. As a ventilation duct, it has the side duct 22 arrange | positioned at the both wall surfaces of the drying chamber 2 in the left-right direction, and the rear upper duct 24 (241) arrange | positioned at the rear wall upper part and the back ceiling corner part of the drying chamber 2. Yes.
The side duct 22 includes an upper duct 221, an intermediate duct 222, and a lower duct 223, and is divided into three stages in the vertical direction. The blowing direction 3F1 (3F) of the hot air 3 blown into the room from the upper duct 221, the middle duct 222, and the lower duct 223 is substantially parallel to the floor surface 261 and faces in the left-right direction. Hot air is blown symmetrically into the drying chamber 2 from the left and right side ducts 22 (221, 222, 223).
Further, the rear upper duct 24 (241) is divided into two stages, upper and lower. The blowing direction 3F2 (3F) of the hot air 3 blown into the room from the rear upper duct 24 (241) faces a direction inclined obliquely forward and downward.

Moreover, as an exhaust duct, the front upper duct 231 which comprises the back duct 242 arrange | positioned under the back wall surface of the drying chamber 2, and the front duct 23 partitioned and arranged above and below the front wall surface, and the front A lower duct 232 and a ceiling corner portion duct 234 (23) disposed in the ceiling corner portions of both wall surfaces in the left-right direction are provided.
The exhaust direction 3R2 (3R) of the hot air 3 exhausted from the rear duct 242 to the outside is substantially parallel to the floor surface 261 and faces the rear. The exhaust direction 3R11 of hot air exhausted from the front upper duct 231 to the outside is substantially parallel to the floor surface 261 and faces the front. The exhaust direction 3R12 of the hot air 3 exhausted from the front lower duct 232 to the outside is substantially parallel to the floor surface 261 and faces the front. The exhaust direction 3R3 (3R) of the hot air 3 exhausted from the ceiling corner duct 234 to the outside is directed obliquely upward in the left-right direction. The hot air 3 exhausted from the front upper duct 231 and the front lower duct 232 is sent to the ceiling corner duct 234 via the arc-shaped external duct 233.
As described above, the air blowing direction 3F of the air duct and the air exhausting direction 3R of the air exhaust duct are formed so as to intersect in the drying chamber 2, and the hot air 3 circulates in the drying chamber 2 without any problems. it can.

<Flow rate and circulation state of hot air flowing in the drying chamber and piping system>
Next, the flow rate and circulation state of the hot air flowing through the drying chamber and the piping system will be described in detail with reference to FIGS. FIG. 3 is a schematic diagram showing the flow rate and circulation state of hot air flowing through the drying chamber of the AA cross section shown in FIG. FIG. 4 is a schematic diagram showing the flow rate and circulation state of hot air flowing through the drying chamber of the BB cross section shown in FIG. FIG. 5 shows a piping system diagram of the drying furnace shown in FIG.

3, in the lower duct 223 of the side duct 22, the flow rate of the hot air blown into the room gradually increases from the rear part 22R in the front-rear direction in the drying chamber 2 toward the central part 22S, and the central part 22S. Is set to gradually decrease toward the front portion 22F.
That is, the flow rate 3F13 of hot air blown into the room from the central portion 22S located at the center in the front-rear direction in the side duct 22 is flow rate 3F11, 3F12 of hot air blown into the room from the front portion 22F located in front of the side duct 22. The flow rate is set higher than the flow rates 3F14 and 3F15 of hot air blown into the room from the rear portion 22R located behind the side duct 22.
In addition, substantially the same amount of hot air flow from the front lower duct 232 and the rear duct 242 is exhausted to the outside toward the front and rear, respectively.

As a result, in the lower layer area close to the floor surface 261 in the drying chamber 2, the hot air 3 flows in a large amount in the left-right direction from the side duct 22 toward the drying chamber central portion 25S, and flows in a large amount toward the drying chamber central portion 25S. The hot air 3 is divided into two while changing the direction in the front-rear direction at the drying chamber central portion 25S and flows to the drying chamber front portion 25F and the drying chamber rear portion 25R. Therefore, in the lower layer area close to the floor surface 261 of the drying chamber 2, the hot air 3 can be circulated strongly in the drying chamber 2 in the left-right direction and the front-rear direction in a direction substantially parallel to the floor surface 261. At this time, since the hot air 3 circulates in a direction substantially parallel to the floor surface 261, there is little possibility that dust, dust, etc. accumulated on the floor surface 261 will be scattered above the drying chamber 2. For this reason, it is possible to reduce the occurrence of defects (one of quality defects) on the surface of the work W while circulating hot air to each part of the work W.
Further, since the cold air tends to accumulate near the floor surface 261 of the drying chamber 2, the hot air 3 is exhausted from the front lower duct 232 and the rear duct 242 adjacent to the floor surface 261 of the drying chamber 2 to the outside. Cold air can also be discharged outside the room. Therefore, it is possible to quickly raise the temperature of the lower part (for example, the locker part) of the work W that is difficult to warm.

Further, as shown in FIG. 4, the upper duct 221 and the middle duct 222 of the side duct 22 are configured such that the flow rate of hot air blown into the room gradually increases from the rear part 22R in the front-rear direction in the drying chamber 2 toward the central part 22S. It is set to increase and gradually decrease from the central portion 22S toward the front portion 22F. This is the same as the lower duct 223. Further, hot air 3 from the rear upper duct 24 (241) is blown into the room in a direction inclined obliquely forward and downward. The flow rate of the hot air 3 is set such that the flow rate 3F22 at the center in the left-right direction is larger than the flow rates 3F21, 3F23 at both ends in the left-right direction.
Further, the flow rate 3R11 of hot air exhausted from the front upper duct 231 toward the front is substantially uniform in the left-right direction.

  As a result, in the upper and middle layers separated from the floor surface 261 in the drying chamber 2, the hot air 3 flows more from the side duct 22 and the rear upper duct 24 (241) to the drying chamber central portion 25S than the lower layer region, and is dried. The hot air 3 that has flowed in a large amount to the chamber central portion 25S changes its direction in the forward direction in the drying chamber central portion 25S, and is exhausted from the drying chamber front portion 25F to the outside. Therefore, in the upper layer region and the middle layer region of the drying chamber 2, the hot air 3 that flows more into the drying chamber central portion 25 </ b> S can be circulated strongly inside the workpiece W (for example, the vehicle interior side). Since the hot air 3 circulates inside the workpiece W, it is possible to positively heat the portion of the workpiece that is difficult to increase in temperature, and to further promote uniform heating of the workpiece W.

As shown in FIGS. 1 to 5, in order to circulate hot air 3 in the drying chamber 2 according to the type and shape of the work W, it is possible to separately control the opening and closing of the pipes connected to each duct. Possible damper valve is connected. For example, different branch pipes branched from the main blower pipe 5 having the blower blower 51 are connected to the front part 22F, the central part 22S, and the rear part 22R of the side duct 22, and separate damper valves 55 are connected to the respective branch pipes. , 54 and 53 are connected. Another damper valve 52 is also connected to the branch pipe to the rear upper duct 24 (241).
Further, a damper valve 64 branched from the main exhaust pipe 6 having the exhaust blower 61 and connected to the branch pipe to the rear duct 242, and a damper valve 62 connected to the branch pipe to the ceiling corner duct 234, The damper valve 63 connected to the branch pipe to the front lower duct 232 can be individually controlled to open and close.

<Raising platform and lifting device>
Next, the elevator and the elevator installed in the drying furnace will be described with reference to FIGS. FIG. 6 is a schematic cross-sectional view showing the elevating device of the drying furnace shown in FIG. FIG. 7 shows a plan view of the lifting platform shown in FIG.

  As shown in FIGS. 6 and 7, the drying chamber 2 is disposed above the workpiece conveyance path 1 on which the workpiece W moves. The floor surface 261 of the drying chamber 2 is formed with an underfloor opening 21 through which the workpiece W can pass. The underfloor opening 21 is mounted on the floor of the drying chamber 2 from the workpiece conveyance path 1 with the workpiece W mounted thereon. It is opened and closed by a rectangular lift 26 that moves up and down to 261. Two rail grooves 263 are formed on the upper end (floor surface) of the lift 26 so that the transport carriage 11 on which the workpiece W is placed travels. The rail groove 263 is formed in parallel in the front-rear direction from the front end to the rear end of the lifting platform 26. The elevator 26 is moved up and down by the lifting device 4 attached to the upper end of the drying chamber 2.

The elevating device 4 includes four support bars 42 extending in the horizontal direction from the left and right ends of the elevating platform 26, a pulling wire 43 connected to one end of each support bar 42, and a drive for winding the pulling wire 43. A motor 44 and a guide pulley 45 for guiding the pulling wire 43 between the support rod 42 and the drive motor 44 are provided. When the drive motor 44 rotates in the clockwise direction, the pulling wire 43 is wound up and the elevator 26 is raised in the direction of the arrow P.
Each support bar 42 is guided by a column 41 connected to the side wall 29 of the drying chamber 2. Since the support bar 42 is raised and lowered while being guided by the support column 41, the parallelism when the elevator 26 is raised and lowered is maintained.
The elevating device 4 is not limited to the wire winding method, and various driving methods such as a four-post hydraulic lifter method and a chain driving method can be selected. In addition, when a 4-post hydraulic lifter system is adopted, it is possible to install hydraulic equipment outside the furnace. Therefore, the cost of the lifter device can be reduced by keeping the heat resistance performance of the hydraulic equipment low.

  In addition, a flat plate heat storage member 262 is mounted on the lifting platform 26. The heat storage member 262 is formed in a size according to the planar size of the workpiece W and is disposed in the center of the lifting platform 26. The heat storage member 262 is fixed to the lifting platform 26 with its upper surface aligned with the upper end (floor surface) of the lifting platform 26. A rail groove 263 is also formed in the heat storage member 262. Hot air circulating near the floor surface 261 in the drying chamber 2 is heated by heat energy stored in the heat storage member 262. For example, ceramics or the like is suitable for the heat storage member 262.

<Work loading / unloading method>
Next, a method for loading and unloading the workpiece into the drying furnace will be described with reference to FIG. FIG. 8 is a side view for explaining a method for loading and unloading the workpiece into the drying furnace shown in FIG. Fig.8 (a) shows the state before throwing the workpiece | work before drying into a drying furnace. FIG. 8B shows a state in which the workpiece before drying is moved to the standby chamber immediately below the drying chamber. FIG. 8C shows a state in which the workpiece W is being dried in the drying chamber. FIG. 8D shows a state in which the dried workpiece has been moved to the standby chamber immediately below the drying chamber.

  As shown in FIG. 8A, the workpiece W before drying placed on the transport carriage 11 is transported to the entrance (IN) of the standby chamber 13 of the drying furnace 10. The transport carriage 11 moves on the work transport path 1. At this time, the elevator 26 is located on the floor surface of the drying chamber 2.

  Next, as shown in FIG. 8B, after the lifting platform 26 is lowered onto the workpiece conveyance path 1, the conveyance carriage 11 on which the workpiece W before drying is placed is moved into the standby chamber 13. The transport carriage 11 stops at a standby position on the lifting platform 26.

  Next, as shown in FIG. 8C, the lifting platform 26 on which the transport carriage 11 on which the workpiece W before drying is placed is raised to the floor surface of the drying chamber 2. Thereafter, hot air is circulated in the drying chamber 2 to heat the workpiece W.

  Next, as shown in FIG. 8D, the elevator 26 is lowered and the dried workpiece W is moved to the standby chamber 13 immediately below the drying chamber. Thereafter, the transport carriage 11 on which the dried workpiece W is placed is moved out of the drying furnace 10. When the next work W is continuously dried, the transport carriage 11 on which the dried work W is placed is moved from the outlet (OUT) to the outside of the drying furnace 10 and at the same time the transport carriage on which the next work W is placed. 11 is introduced from the inlet (IN).

  When the next workpiece W does not come, the elevator 26 is raised to close the underfloor opening of the drying chamber 2 to suppress the release of heat from the furnace. In addition, by providing the entrance (IN) and exit (OUT) doors of the standby chamber 13, it is possible to further suppress the release of heat from the furnace.

<Effect>
As described above in detail, according to the batch-type drying furnace 10 according to the present embodiment, the drying chamber 2 is disposed above the workpiece conveyance path 1 in which the workpiece W moves, and the floor surface of the drying chamber 2 An underfloor opening 21 through which the workpiece W can pass is formed in the H.261, and the underfloor opening 21 is mounted on the elevating platform that carries the workpiece W and moves up and down from the workpiece conveyance path 1 to the floor surface 261 of the drying chamber 2. 26, the transfer carriage 11 on which the work W on the work transfer path 1 is placed is mounted on the lifting platform 26 and put into the drying chamber 2. At the same time, the drying chamber 2 is closed by the lifting platform 26. be able to. Therefore, the movement time of the workpiece W into the drying chamber 2 and the opening time of the drying chamber 2 can be greatly shortened. Therefore, the cycle time of the drying furnace 10 can be shortened and productivity can be improved. Moreover, the time for the hot air 3 to escape from the underfloor opening 21 to the outside of the furnace can be shortened, and wasteful use of energy can be reduced.

  Further, according to the present embodiment, the drying chamber 2 is supplied with air so that the blowing direction 3 </ b> F of the blowing ducts 22, 24 and the exhausting direction 3 </ b> R of the exhaust ducts 23, 242 intersect in the drying chamber 2. Since the ducts 22 and 24 and the exhaust air ducts 23 and 242 are disposed, the hot air 3 can be circulated throughout the drying chamber 2. Therefore, even if there is a part where the temperature rise of the workpiece W is slow somewhere in the drying chamber 2, the hot air 3 can be circulated and heated also to the part where the temperature rise of the work W is slow. Therefore, the heating time of the entire workpiece W can be shortened without being dragged to a portion where the temperature rise is slow. Therefore, the cycle time of the drying furnace 10 can be shortened, the thermal energy can be efficiently used, and the temperature rise difference due to the part of the workpiece W can be reduced.

Further, according to the present embodiment, the air ducts 22 and 24 include the side ducts 22 disposed on the left and right wall surfaces of the drying chamber 2, and the exhaust ducts 23 and 242 include the front of the drying chamber 2. Since the front duct 23 disposed on the directional wall surface and the rear duct 242 disposed on the rear wall surface are included, the hot air 3 flows from the side duct 22 to the drying chamber central portion 25S and to the drying chamber central portion 25S. The hot air 3 can be circulated so as to flow in the front-rear direction and flow to the drying chamber front portion 25F and the drying chamber rear portion 25R. Therefore, in general, the drying chamber central portion 25S in which the portion having a large heat capacity in the workpiece W is disposed has a relatively higher temperature than the drying chamber front portion 25F and the drying chamber rear portion 25R in which the portions having a small heat capacity are disposed. Hot air 3 is supplied.
In particular, since the workpiece W is a finished body of the vehicle, the hot air 3 in the drying chamber 2 is moved to a portion (for example, the B pillar portion or the rocker panel portion) where the temperature is difficult to rise (for example, the B pillar portion or the rocker panel portion) , The hood part and the back door part) can flow in advance, and shortening of the heating time and uniform heating of the entire workpiece W can be promoted simultaneously.

  Moreover, according to this embodiment, the hot air 3 is discharged | emitted from the front lower duct 232 adjacent to the floor surface 261 of the drying chamber 2, and the back duct 242 outside. Since cold air is likely to accumulate near the floor surface 261 of the drying chamber 2, the hot air 3 is discharged from the front lower duct 232 and the rear duct 242 adjacent to the floor surface 261 of the drying chamber 2 to the outside. It can be discharged outside. At this time, since the hot air 3 moves in parallel to the floor surface 261, dust, dust, etc. accumulated on the floor surface 261 are not rolled up. As a result, it is possible to reduce looseness (one of quality defects) adhering to the workpiece W (for example, a finished body of a vehicle).

  Further, according to the present embodiment, the flow rate 3F13 of the hot air 3 blown into the drying chamber 2 from the central portion 22S in the front-rear direction of the side duct 22 is from the front portion 22F and the rear portion 22R in the front-rear direction of the side duct 22. Since there are more flow rates 3F11, 3F12, 3F14, and 3F15 of the hot air 3 that blows into the drying chamber 2, the hot air 3 flows more from the side duct 22 to the drying chamber central portion 25S, and flows more to the drying chamber central portion 25S. The hot air 3 is divided in the front-rear direction and can flow to the drying chamber front portion 25F and the drying chamber rear portion 25R. Therefore, the hot air 3 can be circulated more strongly throughout the drying chamber 2. As a result, the workpiece W in the drying chamber 2 can be heated more rapidly and uniformly.

  Moreover, according to this embodiment, the conveyance trolley | bogie 11 can be made to pass on the raising / lowering stand 26 by one way. Therefore, at the same time as the transport carriage 11 enters from the inlet (IN) of the drying furnace 10, the transport carriage 11 can be withdrawn from the outlet (OUT) of the drying furnace 10. As a result, the time for replacing the workpiece W into the drying furnace 10 can be shortened, and the cycle time of the drying furnace 10 can be further shortened.

  Moreover, according to this embodiment, since the heat storage member 262 is mounted on the lifting platform 26, the hot air 3 circulating near the floor surface 261 in the drying chamber 2 is heated by heat energy stored in the heat storage member 262. Can do. As a result, heat energy can be effectively utilized.

The embodiment described above can be changed without changing the gist of the present invention.
For example, in the above embodiment, hot air is blown into the room from the rear upper duct 24 (241), but the hot air may be discharged from the rear upper duct 24 (241) to the outside of the room.

  INDUSTRIAL APPLICABILITY The present invention can be used, for example, in a batch-type drying furnace in which a coated body of a vehicle is stored for a required time in a sealed drying chamber and dried.

DESCRIPTION OF SYMBOLS 1 Work conveyance path 2 Drying chamber 3 Hot air 3F Air blowing direction 3R Exhaust air direction 3F11, 3F12 Flow rate 3F13, 3F14 Flow rate 3F15 Flow rate 4 Lifting device 10 Drying furnace 21 Underfloor opening 22 Side duct (fan duct)
22F front part 22S center part 22R rear part 23 front duct (exhaust duct)
24 Rear upper duct (air duct)
25S Drying chamber center 25F Drying chamber front 25R Drying chamber rear 26 Lift platform 242 Rear duct (exhaust duct)
261 Floor 262 Heat storage member W Workpiece

Claims (4)

Batch the drying chamber was sealed and a wind exhaust duct for discharging air of the air duct and hot air to the outdoor for blowing hot air into a room, a work to accommodate the time required to dry the workpiece by circulating hot air in the drying chamber A drying oven of the type
The drying chamber is disposed above a workpiece conveyance path through which the workpiece moves, and the floor surface of the drying chamber is formed with an underfloor opening through which the workpiece can pass, and the underfloor opening is It is opened and closed by a lifting platform that carries a workpiece and moves up and down from the workpiece conveyance path to the floor of the drying chamber,
In the drying chamber, the air duct and the air duct so that the air blowing direction of the air duct and the air exhausting direction of the air exhaust duct intersect in the front-rear and left-right directions in a direction substantially parallel to the floor surface in the drying chamber. A batch type drying furnace comprising the exhaust duct. In the batch-type drying furnace according to claim 1,
The blower duct includes side ducts disposed on both left and right wall surfaces of the drying chamber, and the exhaust duct includes a front duct and a rear wall surface disposed on the front wall surface of the drying chamber. A batch-type drying furnace comprising a rear duct disposed in the chamber. In the batch-type drying furnace according to claim 2,
The flow rate of the hot air blown into the drying chamber from the center portion in the front-rear direction of the side duct is larger than the flow rate of hot air blown into the drying chamber from the front portion and the rear portion in the front-rear direction of the side duct. Batch type drying furnace. In the batch-type drying furnace according to claim 1 to claim 3,
A batch-type drying furnace characterized in that a heat storage member is mounted on the lifting platform.

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