JP2014034689A - Heating device for hardening steel plate - Google Patents

Abstract

PROBLEM TO BE SOLVED: To prevent a workpiece from being bent by bending of a workpiece support member, which supports a steel plate to be hardened as a workpiece in a heat chamber, caused by thermal expansion difference.SOLUTION: Heat chambers 17a-17g, each of which carries in and out a plate-shaped workpiece W along a carrying in and out direction along the horizontal direction, are provided in a furnace body 11. Each heat chamber is provided with a workpiece support device 25 which supports the workpiece W. The workpiece support device 25 includes: a plurality of workpiece support members 26 which are formed so as to extend along the carrying in and out direction of the workpiece W; a workpiece support tool which consists of an assembly of a plurality of columnar members 27 fixed to the top of each workpiece support member 26; and a heat shield member 30 which is mounted to each workpiece support member 26. The workpiece support device 25 supports the workpiece W in a state putting the workpiece W on the workpiece support tool consisting of the assembly of the columnar members 27, 27, etc. The heat shield member 30 suppresses heat emission from each workpiece support member 26 and the occurrence of convection above each workpiece support member 26.

Description

  The present invention relates to a steel plate quenching heating apparatus suitable for performing a process of heating to a quenching temperature using a steel plate to be quenched as a workpiece.

  Recently, in order to reduce the weight of a vehicle such as an automobile, it has been practiced to use a thin steel plate made of high carbon steel as a steel plate used for each part of the vehicle and to ensure the strength by hot pressing the thin steel plate. It has come to be. When hot-pressing a raw steel plate, the raw steel plate is heated to a quenching temperature of about 850 ° C. to 950 ° C. and then quenched and quenched at the same time as pressing.

  In order to perform hot pressing, as shown in Patent Document 1, it is necessary to dispose a steel plate quenching heating device that heats the steel plate to the quenching temperature immediately before the press machine. As shown in Patent Document 2, a heating device used for this type of purpose includes a heating chamber that is loaded and unloaded along a horizontal direction with a plate-shaped workpiece oriented in the vertical direction. And configured to heat the workpiece inside the heating chamber. In the heating chamber, there is provided a work support device for placing and supporting the loaded work, and the work supported by the work support device is heated from above and below by an electric heater.

  As shown in FIG. 8, the work support device provided in the conventional heating device is formed so as to extend along the loading / unloading direction of the workpiece W, and arranged in parallel with a space between each other. The plurality of workpiece support members 1, 1,... Are mounted on a fork (hand) of a transfer device (not shown) and loaded into the heating chamber. ,... Are configured to be supported on the surface.

JP 2009-142852 A JP 2008-291284 A

  When the workpiece W at room temperature (about 25 ° C.) is carried into a heating chamber in a high temperature state (for example, 850 ° C. or higher) and placed on the workpiece support members 1, 1,. The heat is directly transferred from the work support member 1, 1,... To the work W, and the heat radiated from the work support member 1, 1,. Due to the convection between the two due to the temperature difference, heat is transferred from the workpiece support members 1, 1,... To the workpiece W, so that the temperature of the upper portion of the workpiece support member decreases. Therefore, the upper parts of the work support members 1, 1,... Are contracted to cause the work support members to bend, and the work support members 1, 1,. To curve. When a workpiece is repeatedly put into the heating chamber for continuous production, the workpiece support members 1, 1,... Will not be able to return to their original shape due to plastic deformation, and the amount of deformation will increase. To do.

  On the other hand, since the workpiece (steel plate) W is heated, its elastic modulus and yield stress (or 0.2% proof stress) are reduced, and it becomes easier to deform than before heating, so that the workpiece support members 1, 1,. If this is the case, the workpiece W will bend accordingly.

  When the workpiece W is bent in this way, when the heated workpiece is carried out by the conveying device, the fork of the conveying device interferes with the workpiece. Also, if the workpiece W is bent, the contact area between the fork of the transfer device and the workpiece is reduced, and the holding of the workpiece becomes unstable. Therefore, the handling performance of the transfer device is reduced in combination with the interference of the fork with the workpiece. Decreases and hinders workpiece transfer. Furthermore, as a result of the unstable holding of the workpiece by the fork of the transfer device, the workpiece position may deviate from the normal position in the process of unloading the workpiece, which may hinder the workpiece machining performed in the next process. . These problems are particularly noticeable when the production tact time is shortened in order to improve productivity.

  As described above, in the conventional steel plate quenching heating apparatus, when a low-temperature work is put into the heating chamber, the long work support member constituting the work support apparatus is deformed, and with use, the The amount of deformation increases and the handling of the transfer device that unloads the workpiece from the heating chamber decreases, or the workpiece is displaced in the process of unloading the workpiece. Therefore, it is necessary to perform maintenance work for correcting the shape of the workpiece support member or replacing the workpiece support member at a short cycle, which increases the cost required for maintaining the heating apparatus for quenching the steel plate. there were.

  An object of the present invention is to provide a heating apparatus for quenching a steel sheet in which a work supporting member extending in the conveying direction of a work (steel sheet) is provided in a heating chamber and the work supported by the work supporting member is heated by a heater. This is to prevent the workpiece support member from being bent due to a temperature difference between the upper and lower portions of the workpiece support member when the workpiece is loaded.

  The present invention includes a workpiece support device that supports a workpiece that is loaded and loaded in a heating chamber in which a workpiece that is a steel plate is loaded and unloaded, and a heater that heats the workpiece supported by the workpiece support device. A heating apparatus for quenching a steel plate is used as a target.

  In the present invention, a work support device includes a plurality of work support members arranged at intervals from each other, and a work support tool that is disposed on each work support member and supports the work. The workpiece support tool comes into contact with the lower surface of the workpiece with a contact area smaller than the contact area between the workpiece support member and the workpiece when the workpiece is directly placed on the workpiece support member. In the present invention, each work support member and work support tool are made of metal.

  As described above, a work support that contacts the lower surface of the work with a contact area smaller than the contact area between the work support member and the work when the work is directly placed on the work support member is disposed on the work support member. When the workpiece is supported by the workpiece support, heat transfer from the workpiece support member to the workpiece can be suppressed when the low-temperature workpiece is carried into the heating chamber and placed on the workpiece support device. Therefore, it is possible to prevent the temperature of the upper part of the work support member from lowering and to prevent the work support member from being bent. The work support member is plastically deformed by repeatedly loading the work into the heating chamber. Can be prevented.

  As a result of preventing the workpiece supporting member from being plastically deformed in this way, it is possible to suppress the bending of the workpiece supported on the workpiece supporting member, so that the fork of the conveying device interferes with the workpiece or the conveying device. It is possible to prevent the contact area between the fork and the work from being reduced and the work holding from becoming unstable, thereby preventing the handling performance of the transfer device from being lowered. In addition, since it is possible to prevent the holding of the work by the fork of the transfer device from becoming unstable, it is possible to prevent the work position from deviating from the normal position during the work unloading process. Can be processed without hindrance.

  In a preferred aspect of the present invention, the work support is composed of a plurality of pin-like members or columnar members that are independent of each other.

  In this case, the plurality of pin-like members or columnar members may be arranged in a state of being separated from each other, or may be arranged side by side in a state where adjacent ones are in contact with each other.

  As described above, when the workpiece support is formed of a columnar member or a pin-shaped member, the contact area between the workpiece support and the lower surface of the workpiece and the cross-sectional area of the workpiece support can be sufficiently reduced. The effect which suppresses the heat transfer from a member to a workpiece | work can be heightened.

  In another preferred aspect of the present invention, a heat shielding member made of a heat insulating material is attached to each work support member, and the heat shielding member radiates heat from each work support member to the work, and from each work support member to the work. Suppresses the occurrence of convection.

  As described above, when a heat shielding member made of a heat insulating material is attached to each work support member, not only can heat be radiated from each work support member to the low-temperature work side, It is possible to suppress the convection from the support member to the work and to prevent the heat from being transferred from each work support member to the work side by the convection, so the heat from the high temperature work support member to the low temperature work It is possible to suppress the temperature of the upper part of the work supporting member from being lowered.

  According to the present invention, since the heat transfer from the work support member to the work side can be suppressed by taking measures against all of the three principles of heat transfer, conduction, convection, and radiation, the work support When a low-temperature work is carried on the apparatus, it is possible to more reliably prevent the temperature of the upper part of the work support member from being lowered and bending of the work support member.

  According to the present invention, the work support that contacts the lower surface of the work with a contact area smaller than the contact area between the work support member and the work when the work is directly placed on the work support member is disposed on the work support member. Since the workpiece is supported by the workpiece support, heat transfer from the workpiece support member to the workpiece is suppressed when a low-temperature workpiece is carried into the heating chamber and placed on the workpiece support device. be able to. Therefore, the bending of the work supported on the work support member can be suppressed, and the fork of the transfer device interferes with the work, or the contact area between the fork of the transfer device and the work is reduced, so that the work is not retained. It can be prevented from becoming stable, and the handling property of the transport device can be prevented from being lowered. In addition, since it is possible to prevent the holding of the work by the fork of the transfer device from becoming unstable, it is possible to prevent the work position from deviating from the normal position during the work unloading process. Can be processed without hindrance.

  According to the invention described in claim 2, the work support is constituted by a plurality of independent pin-shaped members or columnar members, the contact area between the work support and the lower surface of the work, and the cross-sectional area of the work support. Therefore, the effect of suppressing heat transfer from the work support member to the work can be enhanced.

  In the invention described in claim 3, not only the heat transfer from the work support member to the work is suppressed, but also a heat shielding member is attached to each work support member, and the heat radiation from each work support member to the work is performed. Since the occurrence of convection from each workpiece support member to the workpiece is suppressed, heat transfer from the workpiece support member to the workpiece due to thermal radiation and convection can also be suppressed. In this way, in the present invention, measures are taken for all of the three principles of heat transfer, conduction, convection, and radiation, and heat transfer from the work support member to the work side is suppressed. When a low-temperature workpiece is loaded and placed on the workpiece support device, the temperature of the upper portion of the workpiece support member can be prevented more reliably and the workpiece support member can be prevented from bending. .

It is the perspective view which showed the external appearance of one Embodiment of the heating apparatus for steel plate hardening which concerns on this invention. FIG. 2 is a cross-sectional view of the steel plate quenching heating apparatus shown in FIG. 1 taken along a vertical plane when viewed from the front. FIG. 3 is a cross-sectional view showing the internal structure of the present embodiment taken along the line III-III in FIG. 2. (A) And (B) is the front view and side view which showed the example of a structure of the principal part of the workpiece | work support apparatus which supports a workpiece | work in embodiment of this invention, respectively. (A) And (B) is the front view and side view which showed the modification of the workpiece | work supporting member which can be used by this invention, respectively. FIGS. 7A and 7B are a front view and a side view, respectively, showing a partial cross-section of another configuration example of a main part of a work support device that supports a work in the embodiment of the present invention. (A) And (B) is the front view and side view which carried out the partial cross section, and showed further another structural example of the principal part of the workpiece | work support apparatus which supports a workpiece | work in embodiment of this invention, respectively. It is the perspective view which showed the support structure of the workpiece | work in the conventional steel plate hardening heating apparatus. It is the side view which showed the state which the workpiece support member and the workpiece | work supported on it bent in the conventional steel plate hardening heating apparatus.

  Hereinafter, an embodiment of the present invention will be described in detail with reference to the drawings. In the present embodiment, the present invention is applied to a steel plate quenching heating apparatus that heats a thin plate steel plate made of high carbon steel or the like subjected to hot pressing to a quenching temperature as a work W. 1 to 3 show the overall configuration of the heating apparatus of the present embodiment. In these drawings, reference numeral 10 denotes a heating apparatus body including a furnace body 11 formed in a rectangular parallelepiped shape using a heat insulating material, and exterior panels 12A to 12F that cover the outer surface of the furnace body 11. Of the exterior panels 12A to 12F, 12A and 12B are front and back panels respectively covering the front and back of the furnace body 11, 12C and 12D are left and right side panels respectively covering the left and right sides of the furnace body, and 12E and 12F are respectively It is the bottom panel and ceiling panel which cover the bottom face and ceiling surface of a furnace body. In this embodiment, the side which carries in the plate-shaped workpiece | work which is a to-be-heated material is made into the front surface of the heating apparatus main body 10, and the side which carries out the heated workpiece | work is made into the back surface of the heating apparatus main body.

  In order to carry the workpiece W into the heating apparatus main body 10, a plurality (seven in the illustrated example) of carry-in ports 13a to 13g (see FIG. 3) are formed side by side from above on the front side of the heating apparatus main body. Shutters 14a to 14g that open and close these carry-in ports are attached to the front panel 12A. Moreover, in order to carry out the workpiece W after the heat treatment from the inside of the heating chamber main body, the outlets 15a to 15g corresponding to the inlets 13a to 13g, respectively, are formed on the back side of the heating apparatus main body 10 side by side from above. Shutters 16a to 16g that open and close these carry-out ports are attached to the back panel 12B. The carry-in ports 13a to 13g and the carry-out ports 15a to 15g are formed in a horizontally long shape having a rectangular cross section, and the corresponding carry-in ports and carry-out ports are provided at the same height position.

  In the furnace body 11 of the heating apparatus body 10, a plurality (seven in the illustrated example) of heating chambers 17a to 17g corresponding to the carry-in ports 13a to 13g and the carry-out ports 15a to 15g are arranged in multiple stages in the vertical direction. It is formed in a state. In the furnace body 11, a plurality of electric heaters for uniformly heating the insides of the heating chambers 17 a to 17 g from above and below are arranged.

  In the illustrated example, a heater 18 for heating the uppermost heating chamber 17a and the lowermost heating chamber 17g from above and below, respectively, at the uppermost and lowermost portions of a rectangular parallelepiped space formed inside the furnace body 11, and The six heaters 20 are arranged so that the space between the heaters 18 and 19 is divided into seven heating chambers 17a to 17g. It is arranged with the radiation surface along the horizontal direction. The heaters 18, 19, and 20 are electric heaters that have a planar heat radiation surface on both front and back surfaces and radiate heat rays from both front and back surfaces.

  The heaters 18, 19 and 20 used in the present embodiment are electric heaters that are configured to have a panel shape as a whole and emit far infrared rays. As these heaters, a large number of insulators formed with grooves for accommodating heat-generating conductors are lined up, and heat-generating conductors (resistors) that emit far-infrared rays are passed through the grooves of these insulators so that a large number of insulators are flexible. A radiant pad heater having a structure knitted so as to exhibit a flat plate shape or a planar panel heater in which a radiation surface of a heating element (heating resistor) is coated with a far-infrared radiation material can be used. When a pad heater having a flexible plate shape is used as each heater, the heater is flat with the heater mounted on a support tube made of a heat-resistant insulator such as ceramic and fixed to the furnace body 11. To support. When a panel heater is used as each heater, the heater may be fixed to the furnace body 11 through an appropriate fixture, or the heater may be supported in a state of being suspended from the furnace body by a hanging tool fitting. it can.

  As shown in FIGS. 2 and 3, a work support device 25 for placing and supporting the loaded work W is disposed in each of the heating chambers 17a to 17g. Each work support device 25 has a uniform cross-sectional area, is formed so as to extend along the loading / unloading direction of the work W, and a plurality of (not shown) arranged in parallel with a space between them. In the example, three workpiece support members 26 and a workpiece support member made up of an assembly of a plurality of independent columnar members 27 fixed to the upper portion of each workpiece support member 26 are provided. It is comprised so that it may support in the state which mounted the workpiece | work W on the workpiece | work support tool which consists of the aggregate | assembly of the several columnar member 27 each fixed to the upper part. The work support member 26 and the columnar member 27 constituting the work support are preferably made of heat-resistant metal, for example, heat-resistant stainless steel.

  As shown in FIGS. 4A and 4B, the work support member 26 used in the present embodiment is formed so that the contour shape of the cross section is a square or a rectangle and is flat. It consists of a rectangular tube-shaped metal pipe 28 having an outer surface, and is fixed to the heating device main body 10 with one flat outer surface 28a facing upward. The pipes 28 constituting the work support member 26 arranged in each heating chamber are arranged above the heaters arranged in the lower part of each heating chamber in a state where a gap is held between the pipes and the both ends thereof. Is fixed to the furnace body 11 via the mounting bracket 29, thereby being fixed to the heating apparatus main body 10. A large number of through holes h, h,... Are formed on the both side walls of the pipe 28 constituting the work support member 26 at regular intervals in the longitudinal direction of the pipe 28. The plurality of workpiece support members 26 are arranged at positions that do not interfere with the forks of the transfer device that puts the workpiece W in and out of each heating chamber.

  The workpiece support is provided to support the workpiece by contacting the lower surface of the workpiece W with the smallest possible contact area. The workpiece support when the workpiece W is directly supported on the workpiece support member 26 and supported. It is comprised so that the lower surface of the workpiece | work W may be contacted with a contact area sufficiently smaller than the contact area of the member 26 and the workpiece | work W. FIG.

  In the present embodiment, seven columnar members 27 constituting the workpiece support are provided for each workpiece support member 26. A plurality of columnar members 27 provided for each work support member 26 are arranged side by side in the longitudinal direction of the work support member 26 and arranged on a flat upper surface 28 a of a pipe 28 constituting the work support member 26. It is fixed by welding. Each columnar member 27 constituting the work support is formed to have a minimum cross-sectional area necessary to obtain a strength necessary for supporting the work. The intervals between the plurality of columnar members 27 are set so that the workpiece W can be supported without being bent. In order to be able to support the workpiece W horizontally by the workpiece support device 25, all the columnar members 27 constituting the workpiece support have the same height dimension, and the tips of all the columnar members 27 are arranged. (Upper end) is arrange | positioned on the same horizontal surface.

  In the present embodiment, a heat shielding member 30 is provided for each work support member 26, and the heat shield member is attached to each work support member. Each heat shielding member 30 is bound to the pipe 28 by a heat-resistant thread 31 through a through hole h provided in the pipe 28 constituting the work support member 26, and the columnar member 27 fixed to each work support member 26. Are provided in a state of penetrating up and down (in the thickness direction) the heat shielding member 30 disposed on each workpiece support member 26.

  The heat shielding member 30 is provided to suppress heat from radiating from each work support member 26 to the work W side, and to prevent convection (air flow) from occurring above each work support member 26. Therefore, it is formed of a heat insulating material such as ceramic wool that can withstand the heating temperature of the workpiece (800 ° C. to 950 ° C. in this embodiment).

  The width dimension and the thickness dimension of each heat shielding member 30 suppress heat from being radiated from each work support member 26 to the work W side, and convection is generated above each work support member 26 to each work support member. The size is set to a size necessary for suppressing heat from being carried from 26 to the workpiece W. Each heat shielding member 30 preferably has a thickness dimension as large as possible. However, in order not to prevent the workpiece W supported by the workpiece support device 25 from being heated by the heater, the width dimension is In addition, it is preferable to set the minimum size necessary for suppressing the heat radiation from each workpiece support member 26 (for example, the extent equal to or slightly larger than the width dimension of the workpiece support member 26). . It is preferable that the thickness dimension of each heat shielding member 30 is set sufficiently large in a space allowable range so that convection can be prevented from occurring above each work support member 26. Although it is preferable to set the thickness of each heat shielding member 30 as large as possible, it is necessary to set the thickness so as not to exceed the height of the columnar member 27 constituting the work support. In the illustrated example, the thickness dimension of each heat shielding member 30 is set to be slightly smaller than the height dimension of the columnar member 27, and a plurality of pieces fixed to each work support member 26 to constitute a work support tool. These columnar members 27 are arranged in a state where their respective tips penetrate the heat shielding member 30.

  The heating device of the present embodiment is disposed immediately before a press machine that performs hot pressing, and heats a series of material steel plates to be pressed in the heating chambers 17a to 17g as a workpiece W. When heating the workpiece W, the shutters 14a to 14g are opened in a predetermined order to open the carry-in ports 13a to 13g, and the workpiece W held on the fork of the transfer device (not shown) is opened. It is carried into the heating chambers 17a to 17g from the carry-in entrances 13a to 13g, and placed on the work support (columnar members 27, 27,...) Of the work support device 25. After the work is carried into the heating chamber, the work W carried into the heating chambers 17a to 17g is heated by maintaining the shutters 14a to 14g and 16a to 16g closed for a predetermined time.

  Since the work W is carried into the series of heating chambers 17a to 17g at different times, the heating of the work W in the series of heating chambers is completed at a timing shifted by a certain time. After carrying the workpiece W into each heating chamber, the shutter (any one of 16a to 16g) provided for the heating chamber (any one of 17a to 17g) where the heating of the workpiece has been completed is opened, and the opened carriage is opened. The fork of the transfer device is inserted into the heating chamber from the outlet, the workpiece W that has been heated is lifted from the workpiece support device 25, and the workpiece W is unloaded from the heating chamber. The unloaded work is transported to the next processing machine.

  As in the present embodiment, a work support that is made up of an assembly of a plurality of columnar members 27 that are independent from each other and that has a sufficiently small contact area is attached to the upper part of the work support member 26, When the workpiece is supported on the workpiece support member 26 via the workpiece support, when the low-temperature workpiece W is carried into the heating chamber and placed on the workpiece support device 25, the workpiece support member 26 removes the workpiece W from the workpiece support member 26. Heat transfer to the workpiece W can be suppressed. Further, if the heat shielding member 30 is attached to each work support member 26 as in the present invention, not only the heat radiation from the work support member 26 can be suppressed, but also the work support member 26 and the work W It is possible to suppress heat from being transferred by the convection by suppressing the occurrence of convection between the workpiece support member 26, the heat transfer from the workpiece support member 26 to the workpiece, and the low-temperature workpiece W It can prevent that the temperature of the upper part of the workpiece | work support member 26 falls when it carries in in a heating chamber.

  As described above, in this embodiment, measures are taken for all of the three principles of heat transfer, conduction, convection, and radiation, to suppress heat transfer from the work support member 26 to the work W side. As a result, when a low-temperature work W is carried into each heating chamber, the temperature of the upper portion of the work support member in each heating chamber is prevented from lowering, and a large deflection is prevented from occurring in the work support member. It is possible to prevent the workpiece support member from being plastically deformed by repeatedly putting a low temperature workpiece into the heating chamber. Accordingly, it is possible to prevent the workpiece W supported on the workpiece support device from being bent, and the fork of the transfer device that carries the workpiece into and out of the heating chamber interferes with the workpiece, or the fork of the transfer device It is possible to prevent the contact area with the work from being reduced and the work from being held unstable, thereby preventing the handling performance of the transfer device from being deteriorated. In addition, since the work holding by the fork of the transport device can be prevented from becoming unstable, the work position can be prevented from deviating from the normal position during the work unloading process. Can be processed without hindrance.

  In the above embodiment, the work support is composed of an assembly of a plurality of columnar members 27 independent of each other, but each work support is composed of an assembly of a plurality of pin-shaped members (tapered members) independent of each other. It can also be configured. Moreover, a workpiece support can also be comprised with the aggregate | assembly which mixed the columnar member and the pin-shaped member. In addition, when using a pin-shaped member as a member which comprises a workpiece | work support tool, in order not to damage the workpiece | work W, it is preferable to round the upper end (front-end | tip).

  As in the above-described embodiment, a rectangular tube-shaped pipe 28 is used as the work support member 26, and the pipe 28 is fixed to the heating device body with one of the flat outer surfaces of the pipe facing upward. If the columnar member 27 constituting the work support is welded to the flat outer surface directed upward, the columnar member 27 can be easily attached. In addition, not only a rectangular pipe but also a metal pipe having an n-sided cross section (n is an even number of 4 or more) is used as the work support member 26, and one of the flat outer surfaces of the pipe is used. Even if it is fixed to the heating device main body in the state of facing upward, the same effect can be obtained.

  The workpiece support member 26 used in the present invention is not limited to a metal pipe having an n-sided cross-sectional profile. For example, as shown in FIGS. 5A and 5B, the cross-section is circular. It is also possible to use the pipe 35 exhibiting the above as the work support member 26.

  In the above embodiment, the work support provided for each work support member 26 is configured by a plurality of columnar members or pin-like members, but the work support provided for each work support member 26 is formed by a single member. It can also be configured. 6A and 6B show another configuration example of the work support device 25 that can be used in the present embodiment. In this example, the work support is formed in a comb shape. The In the illustrated example, each work support extends in the longitudinal direction of each work support member, and rises upward from both ends in the width direction of the bottom plate part 40a joined to the upper part of the work support member. And a pair of upright walls 40b, 40b extending in the longitudinal direction of each work support member. The pair of upright walls 40b, 40b is the longitudinal direction of each work support member 26. It is formed in a comb-like shape having a large number of comb-tooth portions 40b1, 40b1,. As in the example shown in FIG. 4, the work support member 26 is composed of a rectangular tube-shaped pipe 28 in which a large number of through holes h are formed, and one flat outer surface 28a thereof is arranged upward. The bottom plate portion 40a of the U-shaped member 40 constituting the work support is welded to the outer surface 28a. Also in this case, the heat shielding member 30 having a size capable of suppressing the heat radiation from each work support member 26 to the work W side is disposed on each work support member 26, and constitutes a work support tool. The character-shaped member 40 is provided in a state of penetrating the heat shielding member 30. Although not shown in FIG. 6, the heat shielding member 30 is made of heat-resistant thread through a through hole h provided in the pipe 28 constituting the work support member 26, as in the embodiment shown in FIG. 4. It can be fixed to the pipe 28 by being tied to the pipe 28.

  If the workpiece support is configured as described above, the tips of the comb-like standing walls 40b, 40b come into contact with the lower surface of the workpiece W, so the contact area between the workpiece support and the workpiece W is reduced. Thus, heat transfer from the work support member 26 to the work W can be suppressed. Further, a heat shielding member 30 made of a heat insulating material is disposed on each work support member 26, and the heat shielding member 30 radiates heat from each work support member 26 and convection above each work support member 26. Since generation | occurrence | production is suppressed, it can prevent that the temperature of the upper part of the workpiece | work support member 26 falls, and can prevent that the workpiece | work support member 26 bends by a thermal expansion difference.

  In the example shown in FIG. 6, the comb-shaped work support tool is configured by the U-shaped member 40 in which the pair of standing walls 40 b and 40 b are formed in a comb shape, but as shown in FIG. The workpiece support is constituted by a single comb-like plate 40 'having a large number of teeth 40b1' arranged in the longitudinal direction of the support member 26, and each tooth 40b1 'of the comb-like plate 40' is formed. You may make it the upper end of this contact the lower surface of the workpiece | work W. FIG. Also in this case, the heat shielding member 30 made of a heat insulating material is disposed on each workpiece support member 26, and a comb-like plate 40 'is provided in a state where the heat shielding member 30 is penetrated. This suppresses the radiation of heat from each work support member 26 and the occurrence of convection above each work support member 26.

  In the above embodiment, the heat shielding member 30 is disposed on the workpiece support member. However, the heat shielding member 30 is capable of suppressing thermal radiation from the workpiece support member to the workpiece W side and from the workpiece support member to the workpiece. The heat shield member 30 is not limited to the one shown in the above embodiment, as long as the heat shield member 30 is provided so as to suppress the occurrence of convection to the side. For example, the heat shielding member 30 may be provided so as to cover the upper surface and both side surfaces (side surfaces facing the width direction) of the workpiece support member 26.

  In the above embodiment, the far-infrared heater is used as the heater for heating the heating chamber. However, the present invention can also be applied when other heaters are used.

  In the above embodiment, the present invention is applied to a steel plate quenching heating apparatus having a plurality of heating chambers in multiple stages. However, the present invention can also be applied to a steel sheet quenching heating apparatus having a single heating chamber. it can.

  In the above description, it is assumed that the high carbon steel sheet subjected to hot pressing is heated as a workpiece, but the present invention can of course be applied to a heating apparatus that performs a process of heating other steel sheets to the quenching temperature. It is.

  INDUSTRIAL APPLICABILITY The present invention can be widely used for a steel plate quenching heating apparatus that heats a steel plate to a quenching temperature as a workpiece, and in particular, a step of placing a workpiece on which heat treatment has been completed on a fork of a conveying device and conveying it to the next step. The applicability in various machining fields including

W Work 10 Heating device body 11 Furnace body 12A thru 12F Exterior panel 13a-13g Carry-in port 14a-14g Shutter 15a-15g Carry-out port 16a-16g Shutter 17a-17g Heating chamber 18, 19, 20 Heater 25 Work support device 26 Work support Member 27 Columnar member constituting work support 28 Metal pipe h Through hole provided in pipe 28 Heat shield member 31 made of heat insulating material 31 Heat-resistant thread 35 Pipe with circular cross section 40 Work support U-shaped member 40a Bottom plate portion 40b Comb-like standing wall 40 'Comb-shaped plate

Claims (3)

A heating chamber for loading and unloading a workpiece, which is a steel plate, is provided, and in the heating chamber, a workpiece supporting device for placing and supporting the loaded workpiece, and a heater for heating the workpiece supported by the workpiece supporting device. A steel plate quenching heating device for heating the workpiece to a quenching temperature by the heater,
The work support device includes a plurality of work support members arranged with a space between each other, and a work support tool disposed on each work support member to support the work,
The workpiece support tool is to contact the lower surface of the workpiece with a contact area smaller than the contact area between the workpiece support member and the workpiece when the workpiece is directly placed on the workpiece support member,
Each of the workpiece support members and the workpiece support tool is made of metal,
A heating device for quenching steel sheets.   The said workpiece support tool consists of several pin-shaped members or columnar members which were mutually independent, The heating apparatus for steel plate hardening of Claim 1 characterized by the above-mentioned. A heat shielding member made of a heat insulating material is attached to each work support member,
Suppressing heat radiation from each workpiece support member to the workpiece and occurrence of convection from each workpiece support member to the workpiece by the heat shielding member;
A heating apparatus for quenching a steel sheet according to claim 1 or 2.

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