JPH0712463U - Heat treatment equipment - Google Patents

Abstract

(57) [Summary] [Purpose] Any heat treatment such as annealing and quenching can be performed sequentially according to the heat treatment conditions of the individual workpieces that are continuously conveyed, and cooling facilities can be installed in each of the multiple heat treatment furnaces. It is an object of the present invention to allow a work to be immersed in a cooling liquid tank in a short time without providing the above, and at the same time, to easily discharge sand accumulated in the cooling liquid tank. [Structure] Closed box type heat treatment furnaces 1 and 2 in which temperature conditions can be individually set are lined up with their work loading and unloading ports 5 facing in front, and work loading and unloading for loading and unloading work into and from each heat processing furnace 1 and 2 An elevator device 6 for raising and lowering a lift 7 equipped with a mechanism 8 is arranged so as to be movable along the heat treatment furnaces 1 and 2, and the high-temperature work carried out from the heat treatment furnaces 1 and 2 onto the lift 7 is immersed. The cooling liquid tank 4 is formed so as to be movable to the lowered position of the lift 7, and the cooling tank 4 is provided with a sand discharge port 23 for timely discharging the sand that has fallen from the work and accumulated on the bottom of the tank together with the cooling liquid. ing.

Description

[Detailed description of the device]

[0001]

[Industrial applications]

 The present invention relates to a heat treatment apparatus capable of sequentially carrying in a plurality of workpieces that are continuously conveyed to a heat treatment furnace in which a required number of workpieces are arranged and individually performing heat treatment.

[0002]

[Prior art]

 The heat treatment equipment for heat-treating a continuously conveyed work is roughly classified into a heat treatment furnace of a tunnel type whose both ends are open, and the work is heated while passing it at a constant speed (Japanese Patent Laid-Open No. 2006-242242). No. 61-84321) and a plurality of closely-packed heat treatment furnaces arranged side by side and sequentially close the opening / closing door, and after a certain time elapses, the opening / closing door is opened to sequentially carry out the work. (See Japanese Patent Laid-Open No. 61-76873).

Here, the former continuous heat treatment apparatus is excellent in continuously performing heat treatment under the same heat treatment condition, but when workpieces with different heat treatment conditions are continuously conveyed, Since the line must be stopped and the temperature inside the furnace must be adjusted for each time, the production efficiency is significantly reduced, and the latter causes the work to be carried under different heat treatment conditions continuously even if the work is carried continuously. Heat treatment can be performed individually without stopping the line.

By the way, the heat treatment not only heats the work, but, for example, quenching performed for the purpose of obtaining the maximum hardness of the metal material is performed by immersing the work heated to a predetermined temperature in water or oil and rapidly cooling it. There must be. A cooling device is required to cope with such quenching, and in a tunnel type heat treatment furnace, quenching can be continuously performed by providing one cooling device at the outlet thereof.

[0005]

[Problems to be Solved by the Invention] However, in high-mix low-volume production, for example, different types of cast work are conveyed on the same production line, and the heat treatment conditions are that the first work is high temperature quenching. Since the second work may be different such as low temperature quenching and the third work may be annealing, the heat treatment cannot be performed in the tunnel type heat treatment furnace according to the heat treatment conditions of each work.

On the other hand, in a case where a plurality of closed box type heat treatment furnaces are arranged in parallel, if a cooling liquid tank is to be provided at the outlet of the heat treatment furnace, the cooling liquid tanks and the cooling liquid tanks will be provided for all the heat treatment furnaces. There is a problem that equipment costs increase because it is necessary to provide auxiliary equipment such as a transfer device for dropping the work into the tank. Also, in order to reduce the equipment cost, if a cooling liquid tank is installed in one place and the heated work is transferred to the cooling liquid tank for cooling, the work is gradually cooled during the transfer, There is a problem that a suitable quenching treatment cannot be performed when the cooling rate conditions are severe.

[0007] Furthermore, when the cast work is quenched and the sand of the mold accumulates on the bottom of the tank, the sand adheres to the surface of the work during cooling. Therefore, when sand accumulates, use a pump. Although the sand was pumped out at the same time as the cooling water was pumped out, the pump is liable to break down if the sand is sucked in, and parts must be replaced each time, which increases maintenance costs. there were.

Therefore, the present invention is intended to include not only heat treatment such as annealing and normalizing, but also cooling operation such as quenching, depending on the heat treatment conditions of individual workpieces that are continuously conveyed. The heat treatment can be performed sequentially, and at the same time, it is not necessary to provide a cooling facility for each of the plurality of heat treatment furnaces, which saves the equipment cost. Further, the work can be immersed in the cooling liquid tank in a short time and at the same time The technical issue is to be able to easily discharge the accumulated sand.

[0009]

[Means for Solving the Problems] In order to solve this problem, the present invention provides a closed box type heat treatment furnace in which temperature conditions can be individually set, and the work loading / unloading ports are arranged in a line in front of each heat treatment. An elevator device equipped with a work loading / unloading mechanism for moving the work in and out of the furnace is arranged so as to be movable along the heat treatment furnace, and the high temperature work carried out from the heat treatment furnace onto the lift is moved. A cooling liquid tank to be immersed is formed so that it can move to the lowered position of the lift, and a sand discharge port is formed in this cooling tank to discharge the sand that has fallen from the work and accumulated on the bottom of the tank together with the cooling liquid in a timely manner. It is characterized by

[0010]

[Action]

 Since the temperature of each heat treatment furnace can be set individually, when workpieces with different heat treatment conditions are conveyed, it can be set to an arbitrary temperature according to the heat treatment conditions. Approximately 550 ° C) or a predetermined tempering temperature (for example, approximately 200 ° C). Set different quenching and tempering temperatures depending on the heat treatment conditions.

Next, the workpieces that have been continuously conveyed are placed on a lift, first carried into a heat treatment furnace set at a quenching temperature and subjected to quenching heating, and the heat treatment furnace is adjusted according to the end time. Move the elevator device to the position and move the cooling liquid tank to the descending position of the lift, then carry out the heated work on the lift and lower the lift to the inside of the cooling liquid tank. During that time, the lift and the cooling tank are moved to the heat treatment furnace set to the tempering temperature in the meantime. At the end of cooling, the lift is raised and the work is carried into the heat treatment furnace for tempering. Therefore, one set of the cooling liquid tank and the elevator device is sufficient, and the equipment cost is saved, and at the same time, the work can be immersed in the cooling liquid tank in a short time by lowering the lift on the spot.

Further, when quenching a cast work, even if the sand of the casting mold remaining on the surface of the work falls into the coolant tank and accumulates at the bottom of the tank, the sand discharge port should be opened. As a result, the sand is discharged together with the cooling liquid into, for example, a waste liquid recovery pit formed on the floor.Therefore, the pump does not malfunction due to the suction of sand, and the cooling liquid can be easily replaced, so that the sand accumulates. By replacing it before, sand does not adhere to the surface of the work during cooling.

[0013]

【Example】

 Hereinafter, the present invention will be specifically described with reference to the embodiments shown in the drawings. FIG. 1 is a front view showing the device of the present invention, FIG. 2 is a side view thereof, and FIG. 3 is a perspective view showing a main part thereof.

In the heat treatment apparatus, heaters 1a and 2a are provided respectively, and the closed box type heat treatment furnaces 1 and 2 capable of individually setting the temperature conditions according to the heat treatment conditions of the work have a work transfer path. For example, a work transfer device 3 that is installed in parallel on both sides of the work piece and that transfers a cage C containing a work and transfers it into and out of each of the heat treatment furnaces 1 and 2, and to rapidly cool the work heated during quenching. The cooling liquid tank 4 is provided.

The work transfer device 3 includes a lift 7 having a work loading / unloading mechanism 8 for loading / unloading a work into / from each heat treatment furnace 1 and 2, and an elevator device 6 for moving the lift 7 up and down. Is movably arranged on a rail 9 laid along the front surface of each heat treatment furnace 1 and 2.

The elevator device 6 is composed of a frame 10 that also serves as a guide rail for guiding the lift 7, and an elevating device 11 attached to the frame 10. The elevating device 11 is mounted in parallel on sprocket wheels 13U and 13D arranged vertically. The endless chain 14 and a motor 15 that rotationally drives the upper rocket 13U. The slider 7b of the lift 7 is connected to the endless chain 14. Incidentally, 14a is a balance weight for canceling the weight of the lift 7.

The lift 7 is composed of a pedestal 7a on which the cage C is placed, and a slider 7b attached to the upper end of the pedestal 7a and traveling vertically along the frame 10, the pedestal 7a having a cross section thereof. Is formed smaller than the cooling liquid tank 4, and the cage 7 can be immersed in the cooling liquid tank 4 together with the lift 7 and the upper end of the cage C can be immersed in the cooling liquid tank 4. It is formed at a height so as not to be immersed in the cooling liquid tank 4.

The work loading / unloading mechanism 8 includes a sprocket 19 for moving a chain 17 having a loading / unloading dog 16 formed at its tip end along a lift 7, a frame 10, and guides 18 formed in the heat treatment furnaces 1 and 2, and The elevator motor 6 is provided on both left and right sides of the elevator device 6 so that the work can be carried in and out of the heat treatment furnaces 1 and 2 arranged on both the left and right sides of the work transfer path. The drive motor 20 is attached to the slider 7b at the upper end of the lift 7 so that the work is not submerged even when the work is immersed in the cooling liquid tank 4 by lowering the lift 7.

The cooling liquid tank 4 is movably arranged along a rail 21 laid inside a rail 9 that guides the frame 10 so that it can be positioned directly below the lift 7. . Further, the cooling liquid tank 4 is, for example, a high temperature tank 4a having a water temperature of 80 ° C. and a low temperature tank 4b having a water temperature of 40 ° C. that are connected left and right to form a two tank type, and the high temperature tank 4a is formed according to the cooling temperature of the quenching treatment. Alternatively, one of the low temperature tanks 4b is positioned directly below the lift 7.

In each of the high-temperature tank 4a and the low-temperature tank 4b, when the cast work is cooled, the sand dropped from the work and accumulated at the bottom of the tank is discharged to the waste liquid recovery pit 22 formed on the floor together with the cooling liquid at appropriate times. A sand discharging port 23 is formed, and each tank bottom is formed in a hopper shape that is inclined toward the sand discharging port 23. The sand discharged into the waste liquid recovery pit 22 flows into the settling tank 24 together with the cooling liquid, and is separated into sand and the cooling liquid by using a separating device (not shown) such as a scraping conveyor or a filter. It is regenerated and used as a mold, and the cooling liquid is circulated to the cooling liquid tanks 4a and 4b.

Reference numeral 25 denotes a sand discharging device for discharging the sand dropped from the work of the cast product into the heat treatment furnace 1. The vacuum device 27 is mounted on a carriage 26 that runs along the bottom of the heat treatment furnace 1. Is provided so that the suction port 28 expands and contracts toward the discharge port 29 formed at the bottom of the heat treatment furnace 1, and when the suction port 28 extends and engages with the discharge port 29, The opening / closing door 30 of 29 is opened so that the sand is sucked.

The above is an example configuration of the present invention, and the operation thereof will be described below. First, the temperatures of the heat treatment furnaces 1 and 2 are set according to the heat treatment conditions of the work. For example, a cage C containing a workpiece to be quenched at a quenching temperature of 550 ° C, a cooling temperature of 80 ° C, and a tempering temperature of 200 ° C, and a quenching temperature of 500 ° C, a cooling temperature of 40 ° C, and a tempering temperature of 250 ° C. When the cage C containing the work to be inserted is conveyed at a ratio of 3: 1, for example, the heat treatment furnaces 1 and 2 facing each other across the conveyance path are set as one set, and six sets on the right side in FIG. 1 are set. Regarding the heat treatment furnace X, the heat treatment furnace 1 is set at 550 ° C. and the heat treatment furnace 2 is set at 200 ° C., and the heat treatment furnace 1 is set at 500 ° C. and the heat treatment furnace 2 is set at 250 ° C. for the two sets of heat treatment furnaces Y on the left side.

Then, the elevator apparatus 6 is moved to the work loading / unloading position (not shown), and the cage C is placed on the lift 7 positioned at the height of the work loading / unloading port 5 of the heat treatment furnaces 1 and 2. After that, the elevator apparatus 6 is moved to the front of the desired heat treatment furnace 1 according to the heat treatment conditions of the work in the cage C.

At this time, since the lift 7 is positioned at the height of the heat treatment furnace 1, the work loading / unloading mechanism 8 is activated by opening the door of the work loading / unloading port 5 at that level. The cage 17 is advanced and the cage C is pushed into the heat treatment furnace 1. Next, the cage 17 is left inside the heat treatment furnace 1, the chain 17 is pulled out of the furnace 1, the door of the work loading / unloading port 5 is closed, and the loading operation is completed. Then, each time the cage C is transported, the cage C is sequentially loaded into the heat treatment furnace 1 set to a temperature according to the heat treatment conditions.

Next, the frame 10 is positioned in front of the heat treatment furnace 1 and the cooling liquid tank 4 is positioned directly below the lift 7 in accordance with the end time of the quenching heating. At this time, when cooling the work heated in the heat treatment furnace X, the high temperature tank 4a is positioned directly below the lift 7, and when cooling the work heated in the heat treatment furnace Y, the low temperature tank 4b is lifted. Position it so that it is directly below.

When the quenching heating is completed, the door of the work loading / unloading port 5 is opened, the chain 17 of the loading / unloading mechanism 8 is extended into the heat treatment furnace 1, and the dog 16 at the tip is hooked on the cage C. Simultaneously with pulling out onto the lift 7, the elevator 7 lowers the lift 7 to the lower end position, and the work in the cage C placed on the lift 7 is dipped in the cooling liquid tank 4. If a holding mechanism for fixing the cage C to the lift 7 is provided, the lift 7 can be lowered at a speed faster than free fall, and the work can be dipped into the cooling liquid tank 4a faster. it can.

Next, when the cooling operation is completed, this time, the lift 7 is raised to the height of the heat treatment furnace 2, the cage C is carried into the heat treatment furnace 2, and the tempering process is performed. Then, after tempering and heating for a predetermined time, the elevator device 6 is positioned in front of the heat treatment furnace 2 in accordance with the end time, and the lift 7 is positioned at the height of the work loading / unloading port 5 of the heat treatment furnace 2. The cage C is carried out onto the lift 7, transferred to the workpiece loading / unloading position, and the cage C is unloaded from the lift 7 and sent to the next step.

When the cast work is quenched, the mold sand remaining on the surface of the work falls into the cooling liquid tanks 4a and 4b during quenching in the cooling liquid tanks 4a and 4b. When the sand discharge port 23 is opened when the sand is collected once, the sand in the tank is discharged to the waste liquid recovery pit 22 due to the water pressure as the cooling liquid flows out, so a pump for discharging the sand out of the tank. Etc. are not necessary at all. Then, after the sand and the cooling liquid are separated in the precipitation tank 24, the sand is regenerated and used as a raw material for the mold, and the cooling liquid is supplied again to the cooling liquid tank 4.

In the above-described embodiment, the six heat treatment furnaces X on the right side and the two heat treatment furnaces Y 2 on the left side are set to different temperatures according to the heat treatment conditions of the work, thereby quenching temperature and cooling Only the case of performing two types of heat treatments with different temperatures and tempering temperatures has been described, but since the heat treatment furnaces 1 and 2 can individually control the temperature, the temperature is not limited to two types and the temperature can be adjusted according to any heat treatment condition. Can be set.

For example, when performing annealing, normalizing, etc., the temperature rising rate, the holding temperature, the holding time, the cooling rate, etc. of the heat treatment furnaces 1 and 2 are set in advance, and the heat treatment according to the heat treatment conditions of the work is performed. After the work is carried into the furnace 1 or 2 and subjected to the heat treatment, the work may be sent to the next process without being immersed in the cooling liquid tank 4. Further, the case where the heat treatment furnaces 1 and 2 are installed on both the left and right sides of the workpiece transfer path has been described, but the present invention is not limited to this, and the heat treatment furnaces may be installed in two upper and lower stages. .

[0031]

[Effect of device]

 As described above, according to the present invention, even if workpieces with different heat treatment conditions are continuously conveyed to the same production line, the line can be adjusted according to the heat treatment conditions of individual workpieces without stopping the line. Therefore, not only heat treatment such as annealing and normalizing, but also any heat treatment including cooling operation such as quenching can be sequentially performed, and at the same time, the cooling liquid tank for quenching and the workpiece in the cooling liquid tank are Since it is not necessary to provide a transfer device for dropping into each of a plurality of heat treatment furnaces, it has an excellent effect that the facility cost can be reduced and the time until the immersion in the cooling liquid tank can be shortened. Furthermore, even if sand is accumulated in the cooling liquid tank by quenching the cast product, no pump or the like is needed to discharge the sand out of the tank, so maintenance costs can be reduced. Effect also has.

[Brief description of drawings]

FIG. 1 is a front view showing a heat treatment apparatus according to the present invention.

FIG. 2 is a side view thereof.

FIG. 3 is a perspective view showing a main part thereof.

[Explanation of symbols]

 1 ... Heat treatment furnace 2 ... Heat treatment furnace 3 ... Work transfer device 4 ... Coolant tank 5 ... Work loading / unloading port 6 ... Elevator device 7 ... Lift 8 ... Work loading Ejection mechanism 14 ... Endless chain 23 ... Sand removal port

Claims (1)

[Scope of utility model registration request] 1. A closed box type heat treatment furnace (1, 2) in which temperature conditions can be individually set is lined up with its work loading / unloading port (5) facing the front, and for each heat treatment furnace (1, 2). (7) with work loading / unloading mechanism (8)
Elevator device (6) that raises and lowers the heat treatment furnace (1, 2)
A cooling liquid tank (4), which is arranged so as to be movable along the heat treatment furnace (1, 2) and into which the high-temperature work carried out onto the lift (7) is immersed, is located at the lower position of the lift (7). The heat treatment is characterized in that the cooling tank (4) is provided with a sand discharge port (23) for timely discharging the sand that has fallen from the work and accumulated on the bottom of the tank together with the cooling liquid in the cooling tank (4). apparatus.