Sintering furnace for small-batch sintering

Abstract

The utility model discloses a sintering furnace for small-batch sintering, comprising: a bearing table having a turntable capable of rotating around its own axis, the turntable having a plurality of fixing positions for loading a to-be-sintered object, the fixing positions being arranged on a first concentric circular ring with the axis as the center of circle; the furnace cover is located above the bearing table and matched with the bearing table, and a sintering inner cavity for containing the rotating disc is formed in the furnace cover; the plurality of heating rods are positioned in the sintering inner cavity and are arranged on a second concentric circular ring which takes the axis as a circle center and is arranged at an interval with the first concentric circular ring; the lifting mechanism is used for driving the bearing table or the furnace cover to ascend and descend so that the furnace cover and the bearing table can be combined or separated. The problem of heating uniformity of sintered articles during small-batch production can be solved, and the quality of the sintered articles in batches is guaranteed.

Description

Technical Field

[0001] The present invention belongs to the technical field of high-temperature sintering production, and particularly relates to a sintering furnace for small-batch sintering. Background Art

[0002] A sintering furnace is a thermal equipment, which mainly uses resistance wires for heating and refractory materials for heat insulation and heat preservation. Its working mode is intermittent operation, requiring fast heating, long heat preservation time, and a relatively long working cycle, operating in an atmospheric and normal state mode. However, most sintering furnaces have their inherent furnace body structures. When small-batch production is carried out to improve production efficiency, the temperature in the furnace chamber is uneven, resulting in differences in the quality of the products at the batch sintering site.

[0003] For example, in a crucible sintering furnace, due to the inherent structure of the furnace body of the crucible sintering furnace, there is a problem of uneven temperature in the furnace chamber. Especially when multiple crucibles are sintered at one time to improve production efficiency and reduce production costs, the non-uniformity of the temperature in the furnace chamber is more prominent. Generally, the heaters of the crucible sintering furnace are arranged around the furnace chamber. Although the utilization rate in the furnace chamber is increased and more crucibles to be fired can be placed, there are differences in the temperature uniformity in the furnace chamber, resulting in uneven quality of the fired crucibles. Summary of the Invention

[0004] The present application provides a sintering furnace for small-batch sintering, which can solve the problem of uniform heating of each sintered item during small-batch production and ensure the quality of the batch-sintered items.

[0005] The sintering furnace for small-batch sintering includes:

[0006] A carrier platform having a turntable that can rotate around its own axis, and a plurality of fixing positions for loading objects to be sintered are provided on the turntable, and the fixing positions are arranged on a first concentric ring centered on the axis;

[0007] A furnace cover located above the carrier platform and cooperating with the carrier platform, and a sintering inner cavity for accommodating the turntable is provided in the furnace cover;

[0008] A plurality of heating rods are located in the sintering inner cavity, and the plurality of heating rods are arranged on a second concentric ring centered on the axis and spaced from the first concentric ring;

[0009] A lifting mechanism for driving the carrier platform or the furnace cover to lift so that the furnace cover and the carrier platform are combined or separated.

[0010] Small batches of articles to be sintered are loaded on the fixed positions of the turntable. The lifting mechanism drives the lifting of the bearing platform or the furnace cover. The furnace cover is combined with the bearing platform, and the turntable and the articles to be sintered loaded thereon are sent into the sintering inner cavity of the furnace cover. The heating rods are correspondingly inserted into the gaps between the articles to be sintered. During the sintering process, the articles to be sintered rotate with the turntable. After sintering is completed, the lifting mechanism drives the furnace cover or the bearing platform to lift and separate them to facilitate the loading and unloading operations of the sintered articles. In this application, by evenly arranging the heating rods between each article to be sintered, each article to be sintered is uniformly subjected to thermal radiation. At the same time, in cooperation with the rotation of the bottom turntable, the temperature uniformity in the furnace is further improved, ensuring that the temperature deviation in the furnace is controlled within ±5°C.

[0011] The following also provides several optional ways, but it is not an additional limitation to the above overall solution, but only a further supplement or preference. Without technical or logical contradictions, each optional way can be combined with the above overall solution separately, or multiple optional ways can be combined with each other.

[0012] Optionally, the heating rods are installed on the top of the furnace cover and extend vertically downward.

[0013] Optionally, the top of the furnace cover has a through mounting hole, and the heating rod is installed through the corresponding mounting hole; in the state where the furnace cover and the bearing platform are combined, there is a reserved gap between the furnace cover and the bearing platform.

[0014] The gap between the furnace cover and the bearing platform can, on the one hand, serve as a thermal expansion gap for the material; on the other hand, considering the temperature difference uniformity, when fixing the heating rods at the top, there are more mounting holes and heat leakage occurs. Leaving an appropriate gap at the lower part for heat leakage can make the upper and lower temperature fields more uniform.

[0015] Optionally, the fixed position or the heating rods are arranged at the center of the circle. That is, in one implementation mode, the fixed position is arranged at the center of the circle of the turntable. Correspondingly, the center of the circle in the sintering inner cavity is empty; in another implementation mode, the heating rods are arranged at the center of the circle in the sintering inner cavity. Correspondingly, the center of the circle of the turntable is empty.

[0016] Optionally, the heating rods are arranged at the center of the circle, and the second concentric ring where the heating rods are located is located outside the second concentric ring where the corresponding fixed position is located. That is, in a more preferred implementation mode, the heating rods are arranged at the center of the circle in the heating inner cavity, and the center of the circle of the turntable is empty.

[0017] Optionally, it further includes a rotation driving mechanism for driving the turntable to rotate.

[0018] Optionally, the bearing platform further includes a fixed base; the turntable is installed on the top of the fixed base through a rotating shaft; the rotating shaft is driven by the rotation driving mechanism and drives the turntable to rotate.

[0019] Optionally, the carrier table further includes a support base having a hollow cavity, the fixed base is fixed to the top surface of the support base, and the rotating shaft passes through the fixed base and extends into the hollow cavity of the support base.

[0020] Optionally, the rotation driving mechanism is a motor and is connected to the rotating shaft through a gear transmission group.

[0021] Optionally, it further includes a furnace rack, and the carrier table is placed inside the furnace rack; the lifting mechanism includes a lead screw installed on the furnace rack and extending vertically, and the furnace cover is installed on the lead screw through a lifting nut.

[0022] Optionally, it further includes a lead screw driving mechanism for driving the lead screw.

[0023] Optionally, the lifting mechanism further includes a guide rod fixed to the furnace rack and cooperating with the furnace cover.

[0024] Compared with the prior art, the present application has the following beneficial effects:

[0025] This sintering furnace can place multiple circles of objects to be sintered for sintering at the same time. Through the arrangement of multiple circles of heating rods in the furnace chamber and the rotation of the bottom turntable, while ensuring uniform sintering temperature, the quality and production efficiency are greatly improved. BRIEF DESCRIPTION OF THE DRAWINGS

[0026] Figure 1 is a schematic structural diagram of the sintering furnace of the present application;

[0027] Figure 2 is a schematic cross-sectional view of the distribution of the crucible and the heating rods.

[0028] The reference numerals shown in the drawings are as follows:

[0029] 1. Carrier table, 11. Turntable, 12. Fixed base, 13. Support base;

[0030] 2. Object to be sintered;

[0031] 3. Furnace cover, 31. Sintering inner cavity;

[0032] 4. Heating rod;

[0033] 5. Lifting mechanism, 51. Lifting driving mechanism, 52. Lead screw;

[0034] 6. Rotation driving mechanism;

[0035] 7. Furnace rack, 71. Bottom plate, 72. Vertical frame, 73. Top plate. DETAILED DESCRIPTION OF THE EMBODIMENTS

[0036] Next, the technical solutions in the embodiments of the present application will be clearly and completely described in conjunction with the accompanying drawings in the embodiments of the present application. Obviously, the described embodiments are only a part of the embodiments of the present application, rather than all the embodiments. Based on the embodiments in the present application, all other embodiments obtained by those of ordinary skill in the art without making creative efforts belong to the scope of protection of the present application.

[0037] Unless otherwise defined, all technical and scientific terms used herein have the same meaning as commonly understood by those of ordinary skill in the technical field to which this application belongs. The terms used in the specification of this application herein are only for the purpose of describing specific embodiments and are not intended to limit this application.

[0038] As Figure 1 and Figure 2 shown, a sintering furnace for small-batch sintering includes: a carrier table 1, a furnace cover 3, a plurality of heating rods 4, and a lifting mechanism 5. The carrier table 1 has a turntable 11, and the turntable 11 can rotate around its own axis. The turntable 11 has a plurality of fixed positions for loading the objects to be sintered 2, and the plurality of fixed positions are arranged on multiple concentric first circular rings centered on the axis of the turntable, preferably evenly distributed; the furnace cover 3 is located above the carrier table 1, and the furnace cover 3 has a sintering inner cavity 31; the plurality of heating rods 4 are located in the sintering inner cavity 31 of the furnace cover, and the plurality of heating rods 31 are arranged on multiple concentric second circular rings centered on the axis of the turntable and spaced from the first circular rings, preferably evenly distributed. The furnace cover 3 can be combined with the carrier table 1, and the lifting mechanism 5 drives the carrier table 1 or the furnace cover 3 to lift, so that the furnace cover 3 is combined with the carrier table 1, and the rotation of the turntable and the objects to be sintered 2 thereon is not interfered with in the state where the furnace cover is combined with the carrier table. The turntable 11 and the objects to be sintered 2 loaded thereon are sent into the sintering inner cavity 31 of the furnace cover 3, and the heating rods 4 are correspondingly inserted into the gaps between the objects to be sintered 2 and do not interfere with each other. During the sintering process, the objects to be sintered 2 rotate with the turntable 11. After sintering is completed, the lifting mechanism drives the furnace cover 3 and the carrier table 1 to separate again.

[0039] By improving the arrangement mode of the heating rods 4 and cooperating with the rotation of the bottom turntable 11, the present application solves the problem of uniform heating of each sintered object during small-batch sintering. During the sintering process, the objects to be sintered 2 and the heating rods 3 are arranged on different concentric circular rings to ensure that there are heating zones on both the inner and outer sides of each object to be sintered. Generally, the second concentric circular ring where the heating rods 4 are located is on the outer side of the first concentric circular ring where the corresponding fixed positions are located. It can also be understood that when the heating rods 4 are inserted into the gaps between the objects to be sintered 2, from the inside to the outside, there are successively a circular ring formed by the objects to be sintered 2, a circular ring formed by the heating rods 4, a circular ring formed by the objects to be sintered 2, a circular ring formed by the heating rods 3, and so on, arranged at intervals.

[0040] A fixed position can be arranged at the center of the circle, or a heating rod can be arranged, or both can be left empty. That is, in one implementation, a fixed position is arranged at the center of the turntable. Correspondingly, the center of the sintering cavity is left empty. In another implementation, a heating rod is arranged at the center of the circle. Correspondingly, the center of the turntable is left empty. In still another implementation, the centers of both the turntable and the sintering cavity are left empty. In a more preferred implementation, as Figure 2 shown, a heating rod 4 is arranged at the center of the circle. When the furnace cover 3 and the carrier 1 are combined, the distribution of the fixed position (the object to be sintered 2) and the heating rod 4 on the horizontal projection plane is as follows: the fixed position (the object to be sintered 2) is evenly distributed on the first concentric circles with different radii; the heating rod 4 is distributed at the center of the circle and on the second concentric circles with different radii. The second concentric circle and the first concentric circle have the same center, and the radius of the second concentric circle is greater than the radius of the corresponding first concentric circle. That is, during the sintering process of this implementation, from the inside to the outside, it is successively the heating rod 4 (at the center of the circle), the object to be sintered 2, the heating rod 4, the object to be sintered 2, and the heating rod 4.

[0041] In another implementation where a fixed position (the object to be sintered 2) is arranged at the center of the circle, when the furnace cover and the carrier are combined, the distribution of the fixed position (the object to be sintered 2) and the heating rod on the horizontal projection plane is as follows: the fixed position (the object to be sintered 2) is evenly distributed at the center of the circle and on the first concentric circles with different radii; the heating rod is distributed on the second concentric circles with different radii. The second concentric circle and the first concentric circle have the same center, and the radius of the second concentric circle is greater than the radius of the corresponding first concentric circle. That is, from the inside to the outside, it is successively the object to be sintered 2 (at the center of the circle), the heating rod 4, the object to be sintered 2, and the heating rod 4.

[0042] The heating rod is distributed in the sintering cavity and can be installed at the top of the furnace cover and extend vertically downward. In a specific installation method, the top of the furnace cover has a through installation hole, and the heating rod passes through the corresponding installation hole for fixed installation. The heating rod is electrically connected to an external power supply. The sintering furnace can adopt a resistance heating method, and the heating temperature can reach 1400°C. The heating rod can adopt a silicon carbide rod. In this installation method, since there are many installation holes when fixing the heating rod at the top, there is heat leakage. Therefore, when the furnace cover and the carrier are combined, an appropriate gap is reserved between the furnace cover and the carrier for heat leakage, which can make the upper and lower temperature fields more uniform. On the other hand, the gap between the furnace cover and the carrier can also be used as a thermal expansion gap for the material.

[0043] The turntable 11 of the carrier table 1 can rotate around its own axis, driving the object to be sintered 2 to rotate. The rotation of the turntable can be realized by the rotation driving mechanism 6, and the rotation driving mechanism 6 can adopt conventional driving equipment, such as a motor. To facilitate the installation of the turntable 11 and better cooperate with the furnace cover 3, the carrier table 1 further includes a fixed base 12, which is combined with the furnace cover 3. When the furnace cover is combined with the carrier table, a certain heat leakage gap is reserved between the furnace cover and the fixed base. The turntable 11 is installed on the top surface of the fixed base 12 through a rotating shaft (not shown in the figure), and the rotating shaft is driven by the rotation driving mechanism 6 as described above to drive the turntable to rotate. In a specific installation method, the carrier table 1 further includes a support seat 13 with a hollow cavity. The fixed base 12 is fixed on the top surface of the support seat 13. The rotating shaft penetrates the fixed base 12 and extends into the hollow cavity of the support seat 13. The part of the rotating shaft located in the hollow cavity is connected to the output shaft of the motor through a gear transmission group, and the top end of the rotating shaft is fixed at the center of the turntable. The motor drives the rotating shaft to rotate self, driving the turntable to rotate, and the rotation speed of the turntable is controllable and adjustable.

[0044] The cooperation between the carrier table 1 and the furnace cover 3 can be completed by the lifting of the carrier table 1 or by the lifting of the furnace cover 3. As shown in the Figure 1 embodiment shown, the lifting of the furnace cover 3 is completed by the lifting mechanism. In the embodiment where the furnace cover 3 can be lifted, a furnace frame 7 is further included, and the lifting mechanism 5 is cooperatively installed with the furnace frame 7. In one embodiment, the lifting mechanism 5 includes a lifting driving mechanism 51 and a lead screw 52. The lead screw 52 is vertically installed in the furnace frame and is located at one pair of diagonals of the furnace cover. The lead screw 52 is driven by the lifting driving mechanism 51 installed at the top of the furnace frame 7, and the furnace cover 3 is installed on the lead screw 52 through a lifting nut (not shown in the figure). To make the lifting of the furnace cover more stable, two sets of guide rod mechanisms (not marked in the figure) are arranged at the other two diagonals of the furnace cover.

[0045] As an embodiment of the lifting drive, the lifting driving mechanism 51 outputs through a double shaft and is connected to the elevator of the lead screw, transmitting the rotational motion to the vertically installed lead screw 52 at the corner. In this embodiment, the furnace cover is fixedly installed on the lifting nut, and a single motor drives the rotation of the two sets of lead screws 52 arranged diagonally, driving the lifting nuts matching the lead screws to move up and down to realize the lifting of the furnace cover. In other embodiments, the lifting mechanism can also adopt other conventional driving methods.

[0046] As a specific embodiment of the furnace frame, the furnace frame 7 has a bottom plate 71, a vertical frame 72 and a top plate 73. The carrier table 1 is placed on the bottom plate 71 of the furnace frame. The vertical frame 72 is fixed on the bottom plate, and the top plate 73 is fixed on the top of the vertical frame 72. The lead screw is installed through the top plate and the vertical frame, and the driving device of the lifting mechanism is installed on the top plate 73.

[0047] Taking the sintering crucible as an example, a usage method of the present invention is as follows:

[0048] The crucibles are placed on the turntable 11. The furnace cover 3 is driven to move downward to be combined with the bearing platform 1. The heating rods 4 are evenly inserted between the crucibles. During the sintering process, the turntable drives the crucibles to rotate. This sintering furnace can place multiple circles of crucibles for sintering at the same time. Through the arrangement of multiple circles of heating rods in the furnace chamber and the rotation of the bottom turntable, while ensuring uniform sintering temperature of the crucibles, the quality and production efficiency are greatly improved. After sintering is completed, the furnace cover 3 is driven to open upward to complete the loading and unloading of the crucibles.

[0049] The above-described embodiments merely represent several implementation manners of the present application. The description is relatively specific and detailed, but it should not be construed as a limitation on the scope of the invention patent. It should be noted that for those of ordinary skill in the art, without departing from the concept of the present application, several deformations and improvements can still be made, and these all belong to the protection scope of the present application. Therefore, the protection scope of the patent of the present application shall be subject to the appended claims.

Claims

1. A sintering furnace for small batch sintering, characterized in that: include: The carrier platform has a turntable rotatable around its own axis, and the turntable has a plurality of fixed positions for loading the objects to be sintered, and the fixed positions are arranged on a first concentric ring with the axis as the center; A furnace cover, located above the carrying platform and matched with the carrying platform, wherein the furnace cover has a sintering inner cavity for accommodating the turntable; A plurality of heating rods are located in the sintering inner cavity, and the plurality of heating rods are arranged on a second concentric ring centered on the axis and spaced apart from the first concentric ring; The lifting mechanism is used to drive the supporting platform or the furnace cover to lift and lower so that the furnace cover and the supporting platform can be combined or separated.

2. The sintering furnace according to claim 1, characterized in that: The heating rod is installed on the top of the furnace cover and extends vertically downward.

3. The sintering furnace according to claim 2, characterized in that: The top of the furnace cover is provided with a through installation hole, and the heating rod is installed through the corresponding installation hole; when the furnace cover and the supporting platform are combined, a reserved gap is provided between the furnace cover and the supporting platform.

4. The sintering furnace according to claim 1, characterized in that: The fixing position or the heating rod is arranged at the center of the circle.

5. The sintering furnace according to claim 1, characterized in that: A heating rod is arranged at the center of the circle, and the second concentric circle where the heating rod is located is located outside the second concentric circle where the corresponding fixing position is located.

6. The sintering furnace according to claim 1, characterized in that: It also includes a rotation drive mechanism for driving the turntable to rotate.

7. The sintering furnace according to claim 6, characterized in that: The supporting platform also includes a fixed base; the turntable is installed on the top of the fixed base through a rotating shaft; the rotating shaft is driven by the rotating drive mechanism and drives the turntable to rotate.

8. The sintering furnace according to claim 7, characterized in that: The supporting platform also includes a supporting seat with a hollow cavity. The fixed base is fixed to the top surface of the supporting seat. The rotating shaft passes through the fixed base and extends into the hollow cavity of the supporting seat.

9. The sintering furnace according to claim 8, characterized in that: The rotary drive mechanism is a motor connected to the rotating shaft through a gear transmission group.

10. The sintering furnace according to claim 1, characterized in that: It also includes a furnace frame, and the supporting platform is placed in the furnace frame; the lifting mechanism includes a screw rod installed on the furnace frame and extending vertically, and the furnace cover is installed on the screw rod through a lifting nut.

Images