TWI807965B - A sintering furnace and the sintering method of the workpiece - Google Patents

Abstract

A sintering furnace is used to solve the problems of uneven heating and high cost of conventional workpieces to be sintered. Includes: a furnace body with a sintering space, the furnace body having a furnace mouth, and the furnace mouth is connected with the sintering space and the outside world; and a rotary stage, located in the sintering space, the rotary stage has a base and a rotating body is located above the base rotatably relative to the base, and the rotating stage has a bearing portion, and the bearing portion rotates synchronously with the rotating body. And the sintering method of the workpiece using the sintering furnace.

Description

Sintering furnace and sintering method of workpiece

The invention relates to a sintering furnace and a sintering method of workpieces, in particular to a sintering furnace for sintering workpieces and a sintering method of workpieces using the sintering furnace.

When making castings formed by casting, the shell mold of the casting is made first, molten metal is injected into the shell mold, and the casting is obtained after the molten metal is cooled and solidified. In the shell mold, a wax mold is dipped in slurry, poured with sand, or sand-bonded, so that the slurry covers the surface of the wax mold, and the wax mold covered with slurry is dewaxed as a workpiece, which is sintered in a sintering furnace to form the shell mold.

During the sintering operation of the workpiece, flames are injected into the sintering furnace to form a space with a predetermined temperature, so that the workpiece can be sintered in the space. Due to the uneven temperature in the space, for example, the temperature near the flame port is relatively high, and the temperature far away from the flame port is relatively low. When multiple workpieces are sintered in the space, the difference caused by the uneven temperature in the furnace will cause the quality of each workpiece to be different, resulting in an increase in the defective rate.

Moreover, since the heating equipment needs to continuously heat the furnace to maintain the temperature in the furnace, this also causes waste of energy and increases in production costs.

In order to solve the above problems, the purpose of the present invention is to provide a sintering furnace, the system can use The heating temperature of each sintered product is the same.

The second object of the present invention is to provide a sintering furnace that can recycle the heat energy into the furnace to save energy and reduce production costs.

Directions or similar terms mentioned throughout the present invention, such as "front", "rear", "left", "right", "upper (top)", "lower (bottom)", "inner", "outer", "side", etc., mainly refer to the directions of the attached drawings. Each direction or similar terms are only used to assist in explaining and understanding the various embodiments of the present invention, and are not intended to limit the present invention.

The elements and components described throughout the present invention use the quantifier "a" or "an" for convenience and to provide a general meaning of the scope of the present invention; in the present invention, it should be interpreted as including one or at least one, and a single concept also includes plural situations, unless it clearly means otherwise.

Approximate terms such as "combination", "combination" or "assembly" mentioned in the whole of the present invention mainly include separation without destroying components after connection, or inseparable components after connection, which can be selected by those skilled in the art according to the materials of components to be connected or assembly requirements.

The sintering furnace of the present invention comprises: a furnace body with a sintering space, the furnace body has a furnace mouth, and the furnace mouth communicates with the sintering space and the outside world; a rotating carrier, located in the sintering space, the rotating carrier has a base and a rotating body, the rotating body is rotatable relative to the base and is located above the base, the rotating carrier has a bearing part, and the bearing part rotates synchronously with the rotating body; and a heat collecting module, the heat collecting module has a heat collecting part, and the heat collecting part has a heat collecting space The heat collecting element is connected to the lower end of a ring wall by a bottom plate, and the upper end of the ring wall is connected to the base of the rotating platform, so that the heat collecting element and the rotating stage surround to form the heat collecting space, and the heat collecting space is adjacent to the sintering space, so that the heat energy in the sintering space can be transferred to the heat collecting space.

In the sintering method of the workpiece of the present invention, sintering a workpiece with the above-mentioned sintering furnace includes: sequentially placing a plurality of the workpieces on the supporting portion of the rotary stage through the furnace opening; rotating the supporting portion, and heating the plurality of workpieces on the supporting portion at a temperature of 1200-1400°C for 20-60 minutes, so that the temperature difference between any two heated workpieces is less than 50°C; and sequentially taking out the heated plurality of workpieces from the furnace opening.

Accordingly, in the sintering furnace and the sintering method of workpieces of the present invention, since the rotary stage is located in the sintering space, the rotary stage is used for placing the workpieces to be sintered, and the workpieces to be sintered can continuously change their positions along with the rotation of the rotary stage, so that sintering can be carried out at a uniform temperature, so that the workpieces to be sintered can have consistent processing conditions and achieve the effect of consistent product quality. In addition, preheated hot air can be supplied to the sintering space, which can achieve energy saving effects, which can increase by 15%. Energy saving effect.

Wherein, the furnace body may have a reinforcement, and the reinforcement is located above the furnace mouth. In this way, the strength of the structure around the furnace opening can be improved by the reinforcing member.

Wherein, the reinforcing member may be made of silicon carbide. In this way, the reinforcing member can be made to have good strength, which has the effect of preventing the furnace mouth from collapsing due to long-term use.

Wherein, the base can have a first circular slide rail facing the rotating body, and the rotating body has a second circular sliding rail facing the base so as to be opposite to the first circular sliding rail, and there are several balls or rollers between the first circular sliding rail and the second circular sliding rail. In this way, the rotating body can rotate relative to the base through the balls or rollers.

Wherein, the rotating body may have a circumferential portion with several teeth, a driving gear meshes with the teeth of the rotating body, and a driving member drives the driving gear to rotate. In this way, the driving member has the function of driving the rotating body to rotate relative to the base.

Wherein, the angular velocity when the rotating body rotates may be 0.05-0.3 rad/s. in this way, The rotary body can rotate at an appropriate rotation speed, and has the effect of making each workpiece to be sintered uniformly heated.

Wherein, the bearing part can be formed by splicing and arranging several bearing bricks. In this way, when the bearing part is damaged due to long-term use, only the damaged bearing brick can be replaced, which has the effect of reducing maintenance costs.

Wherein, the several bearing bricks can be stacked into at least two layers. In this way, at least two layers of bearing bricks can also be used for heat insulation to reduce the loss of heat energy to the lower part of the bearing part, thereby maintaining the temperature of the sintering space and reducing energy consumption.

Wherein, the plurality of workpieces are sequentially placed on the bearing portion of the rotary platform through the furnace opening in a state where the bearing portion of the rotary platform is continuously rotating, or in a state where the bearing portion of the rotary platform is rotating at a frequency of rotating for 3 to 7 seconds and then stopping for 5 to 20 seconds. In this way, the worker can place the workpiece while the carrying part is stopped, which has the effect of improving the convenience of use.

Wherein, under the condition that the carrying portion of the rotary stage continues to rotate, or the carrying portion of the rotary stage rotates at a frequency of 3-7 seconds and then stops rotating for 0.5-2 seconds, the plurality of workpieces on the carrying portion are heated. In this way, it has the effect of making each workpiece to be sintered evenly heated.

1: furnace body

11: side wall

111: through hole

12: Furnace mouth

13: reinforcement

14: Hole opening

15: heating element

2: Rotary stage

2a: Base

2b: rotating body

2c: Bearing part

21: The first circular slide rail

22: Second circular slide rail

23: Ball

24: Driver

25: Circumference

251: teeth

26: Drive gear

27: Bearing brick

28,32: Bottom plate

29: Support

3: Collector module

31: heat collector

321: through hole

33: ring wall

34: Extraction parts

35: Exhaust pipe

36: connecting pipe

S1: Sintering space

S2: heat collection space

O: axis

[Fig. 1] A perspective view of a preferred embodiment of the present invention.

[Fig. 2] A side sectional view of a preferred embodiment of the present invention.

[Fig. 3] A sectional view taken along line A-A in Fig. 2.

In order to make the above and other purposes, features and advantages of the present invention more comprehensible, preferred embodiments of the present invention are specifically cited below, together with the accompanying drawings for detailed description; in addition, those marked with the same symbols in different drawings are deemed to be the same, and their descriptions will be omitted.

Please refer to Figures 1 and 2, which is a preferred embodiment of the sintering furnace of the present invention, which includes a furnace body 1 and a rotating carrier 2, and the rotating carrier 2 is located in a sintering space S1 of the furnace body 1 .

The furnace body 1 may have structures such as a base, side walls, and a furnace roof, so that the furnace body 1 surrounds the sintering space S1. The furnace body 1 may be a steel skeleton formed by pouring cement or stacking refractory bricks, so that the furnace body 1 can withstand a high temperature of 1400° C. and have good structural strength. The side wall 11 of the furnace body 1 can have a furnace mouth 12, which communicates with the sintering space S1 and the outside world. Workers can place a workpiece to be sintered into the sintering space S1 through the furnace mouth 12. The workpiece can be, for example, a shell mold. The furnace body 1 can have a reinforcement 13, and the reinforcement 13 can be made of silicon carbide. The reinforcing member 13 can be a pipe body and is placed across the top of the furnace port 12, so that the reinforcing member 13 can be used as a beam of the furnace port 12, or the reinforcing member 13 can be embedded in the peripheral wall of the furnace port 12, and the structural strength around the furnace port 12 can be improved by the reinforcing member 13, so as to avoid the collapse of the furnace port 12 after long-term use.

Please refer to Figures 1 and 3, the side wall 11 has several openings 14, each opening 14 communicates with the sintering space S1, and several heating elements 15 can heat the sintering space S1 through each of the openings 14. The heating elements 15 can be, for example, flame injectors, and the heating elements 15 can use natural gas or liquid gas as fuel to spray flames to the sintering space S1, so that a predetermined temperature is formed in the sintering space S1, and the predetermined temperature can be 1200°C. ~1400°C.

Please refer to FIG. 1 and FIG. 2 , the rotary carrier 2 is located in the sintering space S1 , and the workpiece to be sintered can be placed on the rotary carrier 2 through the furnace mouth 12 . The rotary stage 2 has a base 2a and a rotating body 2b, the rotating body 2b is located above the base 2a, and the rotating body 2b can rotate relative to the base 2a around a virtual axis O. In this embodiment, the base 2a has a first circular slide rail 21 centered on the axis O, and the first circular slide rail 21 faces the rotating body 2b. The rotating body 2b has a second circular slide rail 22 centered on the axis O. The second circular slide rail 22 faces the base 2a to be opposite to the first circular slide rail 21. There are several balls 23 between the first circular slide rail 21 and the second circular slide rail 22. In this way, the rotating body 2b can rotate relative to the base 2a through the balls 23 . In this way, the workpieces to be sintered can not always be in the same position with the rotation of the rotary platform 2 in the sintering space S1 , so that each workpiece to be sintered can constantly change positions, and then can be sintered at a uniform temperature.

Please refer to Figures 1 and 2, the rotating body 2b can be driven to rotate by a driving member 24. In this embodiment, the rotating body 2b has a circumferential portion 25 centered on the axis O. The circumferential portion 25 can have several teeth 251. The driving member 24 can drive a driving gear 26 to rotate, and the driving gear 26 is meshed with the tooth 251 of the rotating body 2b. In this way, the driving member 24 can drive the rotating body 2b to rotate relative to the base 2a. . In addition, the number of teeth of the drive gear 26 is preferably smaller than the number of teeth 251 of the rotating body 2b, which can reduce the rotation speed of the driving member 24 and increase the torque of the rotating body 2b. Preferably, the angular velocity of the rotating body 2b when rotating is 0.05-0.3 rad/s. In this way, the rotating body 2b can rotate at an appropriate rotation speed, so that each workpiece to be sintered can be evenly heated.

The rotating platform 2 has a bearing portion 2c for placing the workpiece to be sintered, and the bearing portion 2c can rotate synchronously with the rotating body 2b. In this embodiment, the bearing part 2c can be formed by splicing and arranging several bearing bricks 27, and the bearing bricks 27 can be formed by pouring cement or stacking refractory bricks. Rotation on a horizontal plane is sufficient in principle, and the present invention is not limited thereto. In this way, when the bearing part 2c is damaged due to long-term use, only the damaged bearing brick 27 can be replaced, which can reduce the maintenance cost. Preferably, the bearing bricks 27 can be stacked in at least two layers. In this way, the bearing bricks 27 of at least two layers can also have heat insulation to reduce heat energy from being lost to the bottom of the bearing part 2c, thereby maintaining the temperature of the sintering space S1 to reduce energy consumption. The several bearing bricks 27 can be directly stacked on the rotating body 2b. Or as shown in the figure, the rotating body 2b has a bottom plate 28, and the bottom plate 28 supports the several load-bearing bricks 27 through several supports 29, so that the several load-bearing bricks 27 can rotate together with the rotating body 2b.

The present invention may further include a heat collection module 3, which can collect the heat energy dissipated from the sintering space S1 toward the lower part 2c. The heat collection module 3 has a heat collection part 31, and a heat collection space S2 is provided in the heat collection part 31. The heat collection space S2 is adjacent to the sintering space S1, so that the heat energy in the sintering space S1 can be transferred to the heat collection space S2. In this embodiment, the heat collecting element 31 can be connected to the lower end of a ring wall 33 by a bottom plate 32, and the upper end of the ring wall 33 is connected to the base 2a of the rotating platform 2, that is, the heat collecting element 31 can be connected to the bottom of the rotating platform 2 to form the heat collecting space S2. The bottom plate 32 and the ring wall 33 are preferably made of heat-insulating material, so that the heat energy formed by the high temperature in the sintering space S1 will be transferred through the rotating platform 2 and concentrated to the heat-collecting space S2, so that the air in the heat-collecting space S2 heats up to form hot gas.

The heat collecting module 3 has an air extraction part 34, which can be an air extraction pump, and the air extraction part 34 communicates with the heat collection space S2 through an air extraction pipe 35. In this embodiment, the air extraction pipe 35 is connected to the heat collection space S2 through a through hole 321 of the bottom plate 32. The suction member 34 communicates with the sintering space S1 through a communication pipe 36 , and the communication pipe 36 can be connected to a through hole 111 of the side wall 11 . In this way, the heat-collecting module 3 can send the hot air in the heat-collecting space S2 to the sintering space S1, and can supply the preheated hot air to the sintering space S1, so as to achieve energy-saving effect, wherein the energy-saving effect can be increased by 15%.

When the sintering furnace of the present invention is used, a plurality of the workpieces are sequentially placed on the loading portion 2c of the rotary platform 2 through the furnace mouth 12 . At this time, the carrying portion 2c of the rotary stage 2 can maintain the state of continuous rotation, or the carrying portion 2c of the rotary stage 2 can rotate at a frequency of 3-7 seconds and then stop rotating for 5-20 seconds, so as to place a plurality of workpieces on the carrying portion 2c. In one embodiment, when the plurality of workpieces are placed on the carrying portion 2c, the number of times the carrying portion 2c stops rotating may be 10-18 times.

Continue to rotate the carrying part 2c, and heat the plurality of workpieces on the carrying part 2c at a temperature of 1200-1400°C for 20-60 minutes, so that the temperature difference between any two heated workpieces is less than 50°C. Preferably, during the process of heating the plurality of workpieces on the carrier portion 2c, the carrier portion 2c of the rotary stage 2 may continue to rotate, or the carrier portion 2c of the rotary stage 2 may rotate at a frequency of 3-7 seconds and then stop rotating for 0.5-2 seconds to heat the plurality of workpieces. After the heating is completed, the heated workpieces are sequentially taken out from the furnace mouth 12 . Preferably, during the process of taking out the plurality of heated workpieces, the supporting portion 2c of the rotary stage 2 can rotate at a frequency of 3-7 seconds and then stop for 1-5 seconds. In this way, the worker can take out the plurality of heated workpieces while the carrying portion 2c is stopped, which has the effect of improving the convenience of use.

To sum up, in the sintering furnace of the present invention, the rotating platform is located in the sintering space, and the rotating platform is used for placing the workpieces to be sintered, so that the workpieces to be sintered can change their positions continuously with the rotation of the rotating platform, and can be sintered at a uniform temperature, so that the workpieces to be sintered can have consistent processing conditions and achieve the effect of consistent product quality.

Although the present invention has been disclosed by using the above-mentioned preferred embodiments, it is not intended to limit the present invention. Any person skilled in the art can make various changes and modifications relative to the above-mentioned embodiments without departing from the spirit and scope of the present invention. It still belongs to the technical scope protected by the present invention. Therefore, the scope of protection of the present invention should include all changes within the context and equivalent scope described in the appended patent claims.

1: furnace body

11: side wall

111: through hole

12: Furnace mouth

13: reinforcement

14: Hole opening

15: heating element

2: Rotary stage

2a: Base

2b: rotating body

2c: Bearing part

21: The first circular slide rail

22: Second circular slide rail

23: Ball

25: Circumference

251: teeth

27: Bearing brick

28,32: Bottom plate

29: Support

3: Collector module

31: heat collector

321: through hole

33: ring wall

34: Extraction parts

35: Exhaust pipe

36: connecting pipe

S1: Sintering space

S2: heat collection space

Claims (11)

A sintering furnace, comprising: a furnace body with a sintering space, the furnace body has a furnace mouth, the furnace mouth communicates with the sintering space and the outside world; a rotating carrier, located in the sintering space, the rotating carrier has a base and a rotating body, the rotating body is rotatable relative to the base and is located above the base, the rotating carrier has a bearing part, and the bearing part rotates synchronously with the rotating body; and a heat collecting module, the heat collecting module has a heat collecting part, and the heat collecting part has a heat collecting space, The heat collecting element is connected to the lower end of a ring wall by a bottom plate, and the upper end of the ring wall is connected to the base of the rotating platform, so that the heat collecting element and the rotating stage surround to form the heat collecting space, and the heat collecting space is adjacent to the sintering space, so that the heat energy in the sintering space can be transferred to the heat collecting space. The sintering furnace according to claim 1, wherein the furnace body has a reinforcement, and the reinforcement is located above the furnace mouth. The sintering furnace according to claim 2, wherein the reinforcement is made of silicon carbide. The sintering furnace according to claim 1, wherein the base has a first circular slide rail facing the rotating body, and the rotating body has a second circular sliding rail facing the base so as to be opposite to the first circular sliding rail, and there are several balls or rollers between the first circular sliding rail and the second circular sliding rail. The sintering furnace according to claim 1, wherein the rotating body has a circumferential portion, and the circumferential portion has several teeth, a driving gear meshes with the teeth of the rotating body, and a driving member drives the driving gear to rotate. The sintering furnace according to claim 1, wherein the angular velocity of the rotating body is 0.05 ~0.3rad/s. The sintering furnace according to claim 1, wherein the bearing part is formed by splicing and arranging several bearing bricks. The sintering furnace according to claim 7, wherein the several load-carrying bricks are stacked in at least two layers. A method for sintering workpieces, using the sintering furnace of any one of claims 1 to 8 to sinter a workpiece, comprising: sequentially placing a plurality of the workpieces on the bearing part of the rotary stage through the furnace opening; rotating the bearing part, and heating the plurality of workpieces on the bearing part at a temperature of 1200-1400 °C for 20-60 minutes, so that the temperature difference between any two heated workpieces is less than 50 °C; and sequentially taking out the heated plurality of workpieces from the furnace opening. A method for sintering workpieces according to Claim 9, wherein the plurality of workpieces are sequentially placed on the bearing portion of the rotary platform through the furnace opening in a state where the bearing portion of the rotary platform is continuously rotating, or in a state where the bearing portion of the rotary platform is rotating at a frequency of rotating for 3 to 7 seconds and then stopping for 5 to 20 seconds. A method for sintering workpieces according to Claim 9, wherein the plurality of workpieces on the bearing portion are heated while the bearing portion of the rotary stage is continuously rotating, or when the bearing portion of the rotating stage is rotating at a frequency of 3 to 7 seconds and then stopped for 0.5 to 2 seconds.

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