A nitriding furnace for silicon nitride ceramics and a processing method thereof

Abstract

The application relates to the technical field of silicon nitride ceramic piece production, in particular to a silicon nitride ceramic piece nitriding treatment furnace and a treatment method thereof. The silicon nitride ceramic piece nitriding treatment furnace comprises a nitriding furnace body, a supporting frame arranged in the nitriding furnace body, a spray head arranged in the nitriding furnace body, a cross driving mechanism installed in the nitriding furnace body, a rotating assembly and multiple groups of lifting assemblies, the lifting assembly is connected with the spray head, the lifting assembly and the rotating assembly are alternately matched, the spray head can intermittently rotate along the circumferential direction of the silicon nitride ceramic piece and reciprocate along the length direction of the silicon nitride ceramic piece, a deflection assembly connected with the lifting assembly and the spray head, the deflection assembly can deflect the spray head to the movement direction of the spray head when the spray head moves, a supporting assembly connected with the supporting frame and the rotating assembly, two groups of jacks connected with the supporting assembly, and the two groups of jacks can alternately lift the silicon nitride ceramic piece when the rotating assembly moves, so as to accelerate the nitriding treatment speed and improve the nitriding treatment effect.

Description

TECHNICAL FIELD

[0001] The present application relates to the technical field of silicon nitride ceramic production, in particular to a silicon nitride ceramic nitriding treatment furnace and a treatment method thereof. BACKGROUND

[0002] Silicon nitride ceramic is an important structural ceramic material. It is an ultra-hard substance, has lubricity itself, and is resistant to wear; silicon nitride ceramic is resistant to oxidation at high temperatures, and it can also resist thermal shock, and will not break when heated to above 1000℃ in air, rapidly cooled and then rapidly heated. Due to the excellent properties of silicon nitride ceramic, it is often used to manufacture mechanical components such as bearings, gas turbine blades, mechanical seal rings, and permanent molds.

[0003] In the production process of silicon nitride ceramic, nitriding treatment is required to improve the structural strength. The existing silicon nitride ceramic nitriding treatment is mostly carried out in a nitriding treatment furnace. However, the conventional nitriding furnace generally uses a straight-through nitrogen gas method to make nitrogen gas permeate in the furnace, and the nitriding treatment is carried out by natural permeation of nitrogen gas, which takes a long time.

[0004] If a direct blowing method is used for nitriding treatment of the ceramic parts in the nitriding furnace, the nitrogen gas will flow vertically in the opposite direction when encountering resistance, hindering the gas nozzle from blowing. The nitrogen gas in the nitriding furnace cannot achieve the effect of purging and nitriding, and the nitriding effect is poor. SUMMARY

[0005] The present application aims to provide a silicon nitride ceramic nitriding treatment furnace and a treatment method thereof to solve the problems raised in the background.

[0006] To achieve the above-mentioned purpose, the present application provides the following technical scheme:

[0007] A silicon nitride ceramic nitriding treatment furnace, comprising:

[0008] A nitriding furnace body, wherein a supporting frame for supporting silicon nitride ceramic parts is arranged in the nitriding furnace body;

[0009] A spray head is arranged in the nitriding furnace body, and the spray head can blow heated nitrogen gas to the side of the silicon nitride ceramic part;

[0010] A cross-drive mechanism is installed in the nitriding furnace body, and the cross-drive mechanism comprises a rotating assembly and a plurality of lifting assemblies. The lifting assembly is connected to the spray head, and the lifting assembly and the rotating assembly are alternately matched to enable the spray head to rotate intermittently along the circumferential direction of the silicon nitride ceramic part and reciprocate along the length direction of the silicon nitride ceramic part;

[0011] A deflection assembly is connected to the lifting assembly and the spray head, and is capable of deflecting the spray head to the direction of movement of the spray head when the spray head is moving;

[0012] A support assembly is connected to the cradle and the rotating assembly, and two groups of jacks are connected to the support assembly, and the two groups of jacks are capable of alternately jacking up the silicon nitride ceramic piece when the rotating assembly is in action.

[0013] As a further scheme of the present application, the rotating assembly comprises a rotating piece rotatably installed on the nitriding furnace body, a rotating shaft of the rotating piece is a hollow structure, and a rotating sleeve is rotatably installed in the rotating shaft of the rotating piece, and the cradle is fixedly connected to the nitriding furnace body through a vertical shaft penetrating the rotating sleeve;

[0014] The rotating assembly further comprises a driving device arranged at the bottom of the nitriding furnace body, the driving device is connected to the rotating sleeve through a first transmission chain and connected to the rotating piece through a second transmission chain.

[0015] As a further scheme of the present application, the plurality of lifting assemblies are connected through a fourth transmission chain;

[0016] The lifting assembly comprises a vertical plate arranged perpendicularly to the rotating piece, two transmission wheels are rotatably installed on the vertical plate, and a connecting chain is sleeved between the two transmission wheels;

[0017] The lifting assembly further comprises a follower arranged on the vertical plate, the follower is connected to the spray head, and the follower is connected to the connecting chain through an embedded structure;

[0018] A bevel gear set is further arranged on the vertical plate, the bevel gear set is connected to one of the transmission wheels, and the bevel gear set is connected to the rotating sleeve through a third transmission chain.

[0019] As a further scheme of the present application, the embedded structure comprises an embedded wheel rotatably installed on the connecting chain and an embedded groove formed on the follower, and the embedded wheel is capable of rolling in the embedded groove;

[0020] Sliding grooves are arranged on both sides of the vertical plate along the length direction of the vertical plate, and a sliding block installed on the follower is capable of sliding in the sliding grooves.

[0021] As a further scheme of the present application, the deflection assembly comprises a rotating shaft rotatably installed on the follower and connected to the spray head, one deflection rod is arranged on each side of the rotating shaft, an abutting wheel is rotatably installed on the end of the deflection rod away from the rotating center of the deflection rod, and an upper trigger and a lower trigger arranged on the vertical plate are capable of cooperating with the abutting wheel to drive the rotating shaft to rotate;

[0022] The deflection assembly further comprises an energy storage structure arranged on the follower and connected with the rotating shaft.

[0023] As a further scheme of the present application, the energy storage structure comprises a lagging sleeve symmetrically arranged on the side wall of the follower, a connecting shaft is slidingly arranged in the lagging sleeve, and a pulley is rotatably arranged at one end of the connecting shaft away from the lagging sleeve.

[0024] A spring is further arranged in the lagging sleeve, one end of the spring is connected with the inner wall of the lagging sleeve, and the other end of the spring is connected with the connecting shaft.

[0025] The energy storage structure further comprises a locking member matched with the pulley.

[0026] As a further scheme of the present application, the locking member is fixedly connected with the rotating shaft, two lagging grooves are arranged on the locking member, the two lagging grooves are connected through two inclined surfaces, and a protruding part is formed at one end of the two inclined surfaces away from the lagging grooves.

[0027] When the rotating shaft rotates, the pulley can be switched from one of the lagging grooves to the other lagging groove through the two inclined surfaces.

[0028] As a further scheme of the present application, the inside of the rotating shaft is communicated with the spray head, and a plurality of through grooves are arranged on the rotating shaft.

[0029] A ring-shaped connecting member covering the through grooves is sealingly and rotatably arranged on the rotating shaft, the ring-shaped connecting member is communicated with an inner sleeve ring fixed on the vertical plate through a connecting pipe, and the inner sleeve ring is sealingly and rotatably connected with an outer sleeve ring fixed in the nitriding furnace body.

[0030] As a further scheme of the present application, the supporting assembly comprises an outer top ring and an inner top ring which are concentric and have different diameters, a first fan-shaped abutting member is arranged at the bottom of the outer top ring, a second fan-shaped abutting member is arranged at the bottom of the inner top ring, and the first fan-shaped abutting member and the second fan-shaped abutting member are arranged in a staggered manner.

[0031] The supporting assembly further comprises a follower roller rotatably arranged on the rotating member and matched with the first fan-shaped abutting member and the second fan-shaped abutting member.

[0032] A method for processing a silicon nitride ceramic piece by using the nitriding treatment furnace, comprising the following steps:

[0033] Step one: connecting the external nitrogen gas pump with the equipment and the pipeline of the nitriding treatment furnace body;

[0034] Step two: lift the upper cover of the nitriding furnace body, place the silicon nitride ceramic piece to be treated on the support frame, align the central axis of the silicon nitride ceramic piece to be treated with the key center line of the support frame, then reset the upper cover of the nitriding furnace body, and tighten it with bolts to seal it;

[0035] Step three: start the external nitrogen gas pump to the device, and start the cross drive mechanism. When the cross drive mechanism is working, it will drive the nozzle to make reciprocating motion in the vertical direction of space and stepwise circular motion along the central axis of the silicon nitride ceramic piece to be treated, so that the nitrogen gas is uniformly sprayed on the silicon nitride ceramic piece to be treated;

[0036] Step four: when the nozzle moves upward, the nozzle will be in an inclined upward state, and when the nozzle moves downward, the nozzle will be in an inclined downward state, and the nitrogen gas will be inclined to the silicon nitride ceramic piece to be treated;

[0037] Step five: with the movement of the rotating assembly, the two groups of top rods on the supporting assembly will be alternately lifted to switch the abutting position of the top rods on the silicon nitride ceramic piece to be treated;

[0038] Step six: repeat steps three to five above, and continue for about 10-15h, then take out the silicon nitride ceramic piece, and complete the nitriding treatment.

[0039] Compared with the prior art, the beneficial effects of the present application are:

[0040] By setting the cross drive mechanism, the nitrogen gas is directly sprayed to the surface of the silicon nitride ceramic piece to be treated, the nitrogen gas atmosphere concentration of the silicon nitride ceramic piece to be treated in the nitriding furnace body is improved, and the nitrogen gas directly acts on the surface of the silicon nitride ceramic piece to be treated, the temperature loss of the nitrogen gas is reduced, the nitriding effect and the nitriding speed are improved, and the circular motion and the reciprocating motion of the nozzle cooperate with each other, so that the nitrogen gas can be uniformly sprayed on the silicon nitride ceramic piece to be treated during the nitriding treatment, thereby further strengthening the nitriding effect;

[0041] By setting the deflection assembly, the deflection direction of the nozzle can be automatically switched to the movement direction when the nozzle moves, so that the nitrogen gas can be inclined to act on the silicon nitride ceramic piece to be treated, and the silicon nitride ceramic piece to be treated can be subjected to pre-nitriding and nitriding in turn, thereby further improving the nitriding treatment effect. On the one hand, the inclined spraying of nitrogen gas improves the contact area between nitrogen gas and the silicon nitride ceramic piece to be treated, and on the other hand, it improves the stability of the nitrogen gas flow, avoids turbulence of the nitrogen gas in the nitriding furnace body, and compared with the vertical spraying, the inclined spraying avoids the airflow when the nitrogen gas impacts the silicon nitride ceramic piece to be treated and moves reversely, avoids the gas outlet of the nozzle being blocked, and reduces the load of the external nitrogen gas pump to the device;

[0042] By setting the support assembly, when the follower roller follows the rotation piece to do the circular motion, it can alternately act on the first fan-shaped abutting piece and the second fan-shaped abutting piece, so that the outer top ring and the inner top ring are alternately lifted, so that the two groups of top rods are alternately lifted, and the lifting position when the silicon nitride ceramic piece is lifted is switched, so that the bottom of the silicon nitride ceramic piece can also be well nitrided during the nitriding process. Compared with the existing nitriding treatment furnace, the range of treatment is larger when the silicon nitride ceramic piece is treated, and the bottom of the silicon nitride ceramic piece is avoided due to shielding and insufficient nitriding. BRIEF DESCRIPTION OF DRAWINGS

[0043] Figure 1 A structure schematic view of an embodiment of the nitriding treatment furnace for the silicon nitride ceramic piece.

[0044] Figure 2 A structure schematic view of another angle in an embodiment of the nitriding treatment furnace for the silicon nitride ceramic piece.

[0045] Figure 3 A structure schematic view of the internal structure of the nitriding furnace body in an embodiment of the nitriding treatment furnace for the silicon nitride ceramic piece.

[0046] Figure 4 A structure schematic view of the cross drive mechanism in an embodiment of the nitriding treatment furnace for the silicon nitride ceramic piece. Figure 3 An enlarged view of the structure at A in the figure.

[0047] Figure 5 A structure schematic view of the cross drive mechanism in an embodiment of the nitriding treatment furnace for the silicon nitride ceramic piece.

[0048] Figure 6 A structure schematic view of the deflection assembly in an embodiment of the nitriding treatment furnace for the silicon nitride ceramic piece.

[0049] Figure 7 A partial exploded view of the deflection assembly in an embodiment of the nitriding treatment furnace for the silicon nitride ceramic piece.

[0050] Figure 8 An exploded view of the rotation piece, the rotation sleeve and the vertical shaft in an embodiment of the nitriding treatment furnace for the silicon nitride ceramic piece.

[0051] Figure 9 An exploded view of the support assembly in an embodiment of the nitriding treatment furnace for the silicon nitride ceramic piece.

[0052] Figure 10 An exploded view of the fitting structure in an embodiment of the nitriding treatment furnace for the silicon nitride ceramic piece.

[0053] Figure 11 An exploded view of the outer sleeve ring and the inner sleeve ring in an embodiment of the nitriding treatment furnace for the silicon nitride ceramic piece.

[0054] In the figure: 1, nitrogenization furnace body; 2, driving device; 3, No. 1 transmission chain; 4, No. 2 transmission chain; 5, rotating part; 6, rotating sleeve; 7, vertical shaft; 701, bearing bracket; 8, vertical plate; 801, sliding groove; 9, No. 3 transmission chain; 10, bevel gear set; 11, transmission wheel; 12, connecting chain; 1201, fitting wheel; 13, follower; 1301, fitting groove; 14, sliding block; 15, spray head; 1501, rotating shaft; 1502, through groove; 16, annular connecting piece; 17, deflection lever; 1701, abutting wheel; 18, lower trigger; 19, upper trigger; 20, locking piece; 2001, lagging groove; 2002, inclined surface; 21, pulley; 22, connecting shaft; 23, spring; 24, lagging sleeve; 25, connecting pipe; 26, inner sleeve ring; 27, outer sleeve ring; 28, outer top ring; 2801, No. 1 sector abutting piece; 29, inner top ring; 2901, No. 2 sector abutting piece; 30, jacking rod; 31, No. 4 transmission chain; 32, follower roller. DETAILED DESCRIPTION

[0055] The technical solutions in the embodiments of the present application will be clearly and completely described below with reference to the drawings in the embodiments of the present application. Obviously, the described embodiments are only part of the embodiments of the present application, rather than all the embodiments of the present application. Based on the embodiments in the present application, all other embodiments obtained by those skilled in the art without creative work fall within the scope of protection of the present application.

[0056] In addition, the elements in the present application are referred to as "fixed to" or "provided on" another element, which can be directly on another element or can have a middle element. When an element is considered to be "connected" to another element, it can be directly connected to another element or can have a middle element. The terms "vertical", "horizontal", "left", "right" and similar expressions used herein are only for illustrative purposes and do not represent the only implementation.

[0057] Please refer to Figures 1-11In the embodiment of the present application, a nitriding treatment furnace for silicon nitride ceramic parts comprises a nitriding furnace body 1, a spray head 15, a cross drive mechanism, a deflection assembly and a support assembly, so that when the spray head 15 moves, its deflection direction can be automatically switched to its movement direction, and the nitrogen gas can be inclined to act on the silicon nitride ceramic parts to be treated, so that the silicon nitride ceramic parts to be treated sequentially undergo pre-nitriding treatment and nitriding treatment, thereby further improving the nitriding treatment effect, and the inclined spraying of the nitrogen gas improves the contact area between the nitrogen gas and the silicon nitride ceramic parts to be treated on the one hand, and improves the stability of the nitrogen gas flow on the other hand, avoids turbulence of the nitrogen gas in the nitriding furnace body 1, and compared with vertical spraying, the inclined spraying avoids the airflow when the nitrogen gas impacts the silicon nitride ceramic parts to be treated and moves reversely, avoids the gas outlet of the spray head 15 being blocked, reduces the load of the external nitrogen gas pump equipment, and at the same time, when the follower roller 32 follows the rotating part 5 to do the circular motion, it can alternately act on the first fan-shaped abutting part 2801 and the second fan-shaped abutting part 2901, so that the outer top ring 28 and the inner top ring 29 are alternately lifted, thereby the two groups of top rods 30 are alternately lifted, to switch the lifting position when the bottom of the silicon nitride ceramic part is lifted, and to ensure that the bottom of the silicon nitride ceramic part can also be well nitrided during the nitriding treatment process. Compared with the existing nitriding treatment furnace, the present application has a larger treatment range when treating the silicon nitride ceramic parts, and avoids insufficient nitriding of the bottom of the silicon nitride ceramic part due to shielding.

[0058] Specifically as follows: the nitriding furnace body 1 is provided with a support frame 701 for bearing the silicon nitride ceramic parts;

[0059] The spray head 15 is arranged in the nitriding furnace body 1, and the spray head 15 can blow the heated nitrogen gas to the side of the silicon nitride ceramic part;

[0060] The cross drive mechanism is installed in the nitriding furnace body 1, and the cross drive mechanism comprises a rotating assembly and a plurality of lifting assemblies, the lifting assembly is connected with the spray head 15, and the lifting assembly and the rotating assembly are alternately matched, so that the spray head 15 can intermittently rotate along the circumferential direction of the silicon nitride ceramic part and reciprocate along the length direction of the silicon nitride ceramic part;

[0061] The rotating assembly comprises a rotating part 5 rotatably installed on the nitriding furnace body 1, the rotating shaft of the rotating part 5 is a hollow structure, and a rotating sleeve 6 is rotatably installed in the rotating shaft of the rotating part 5, and the support frame 701 is fixedly connected with the nitriding furnace body 1 through a vertical shaft 7 penetrating the rotating sleeve 6;

[0062] The rotating assembly further comprises a driving device 2 arranged at the bottom of the nitriding furnace body 1, the driving device 2 is connected with the rotating sleeve 6 through a first transmission chain 3 and connected with the rotating part 5 through a second transmission chain 4;

[0063] The plurality of lifting assemblies are connected by the fourth transmission chain 31, and each lifting assembly comprises a vertical plate 8 arranged perpendicularly to the rotating member 5, two transmission wheels 11 rotatably arranged on the vertical plate 8, and a connecting chain 12 arranged between the two transmission wheels 11;

[0064] The lifting assembly further comprises a follower 13 arranged on the vertical plate 8, the follower 13 is connected to the spray head 15, and the follower 13 is connected to the connecting chain 12 through an embedded structure;

[0065] The vertical plate 8 is further provided with a bevel gear set 10, the bevel gear set 10 is connected to one of the transmission wheels 11, and the bevel gear set 10 is connected to the rotating sleeve 6 through the third transmission chain 9;

[0066] The bevel gear set 10 comprises a first bevel gear and a second bevel gear rotatably arranged on the vertical plate 8 and meshing with each other, the first bevel gear is connected to the transmission wheel 11, and the second bevel gear is connected to the third transmission chain 9;

[0067] The embedded structure comprises an embedded wheel 1201 rotatably arranged on the connecting chain 12 and an embedded groove 1301 formed on the follower 13, the embedded wheel 1201 can roll in the embedded groove 1301, and the vertical plate 8 is provided with a sliding groove 801 along the length direction of the vertical plate 8, and a sliding block 14 rotatably arranged on the follower 13 can slide in the sliding groove 801;

[0068] The rotating shaft 1501 is in communication with the spray head 15, and the rotating shaft 1501 is provided with a plurality of through grooves 1502, and the rotating shaft 1501 is further provided with a ring-shaped connecting piece 16 rotatably arranged on the through grooves 1502, the ring-shaped connecting piece 16 is in communication with an inner sleeve ring 26 fixed on the vertical plate 8 through a connecting pipe 25, and the inner sleeve ring 26 is rotatably connected to an outer sleeve ring 27 fixed in the nitriding furnace body 1.

[0069] In use, the silicon nitride ceramic piece to be treated is placed on the support frame 701, while the nitrogen furnace body 1 is in a sealed state, the driving device 2 is controlled to work, and the driving device 2 drives the rotating piece 5 and the rotating sleeve 6 to rotate in sequence when working. Specifically, the rotating piece 5 only rotates by a certain angle, so that the vertical plate 8 and the spray head 15 move along the circumferential direction of the silicon nitride ceramic piece to be treated. After the rotating piece 5 is in the locked state, the rotating sleeve 6 will rotate, at this time, the rotating sleeve 6 will drive one of the transmission wheels 11 to rotate through the No. 3 transmission chain 9 and the bevel gear set 10, so that the connecting chain 12 between the two transmission wheels 11 moves. The connecting chain 12 can be regarded as being composed of two circular segments and two straight line segments. When the fitting wheel 1201 moves on the straight line segment of the connecting chain 12, the fitting wheel 1201 will be in a relatively static state with the fitting groove 1301. At this time, the follower 13 will move up or down along the length direction of the sliding groove 801. When the fitting wheel 1201 moves on the circular segment of the connecting chain 12, the fitting wheel 1201 will roll in the fitting groove 1301, so that the follower 13 continues to move up or down and then moves reversely. At this time, with the continuous rotation of the transmission wheel 11, the follower 13 can be driven to move back and forth along the length direction of the sliding groove 801 under the cooperation of the fitting wheel 1201 and the fitting groove 1301, so that the nitrogen gas is directly sprayed on the silicon nitride ceramic piece to be treated through the spray head 15. The circular motion of the spray head 15 and the reciprocating motion are coordinated with each other, so that the nitrogen gas can be uniformly sprayed on the silicon nitride ceramic piece to be treated during the nitriding process, the nitriding speed is improved, and the nitriding effect is strengthened.

[0070] Further, before use, the external nitrogen gas pumping equipment needs to be connected to the outer sleeve ring 27 through a pipeline. During use, the external nitrogen gas pumping equipment can first heat the nitrogen gas to a predetermined temperature, and then pump the heated nitrogen gas into the outer sleeve ring 27. The outer sleeve ring 27 and the inner sleeve ring 26 form an annular chamber, so that the heated nitrogen gas enters the annular chamber and then enters the annular connecting piece 16 through the connecting pipe 25, and then enters the spray head 15 through the through slot 1502. Therefore, the heated nitrogen gas can be sprayed on the silicon nitride ceramic piece to be treated. When the rotating piece 5 rotates by a small angle, the vertical plate 8 drives the inner sleeve ring 26 to rotate synchronously relative to the outer sleeve ring 27, so that the two ends of the connecting pipe 25 are located on the same vertical plane, thereby avoiding the phenomenon that the connecting pipe 25 is twisted and separated from the rotating piece 5, and ensuring the stability of the nitrogen gas pumping.

[0071] Through the above arrangement, the nitrogen is directly sprayed to the surface of the silicon nitride ceramic piece to be treated, the nitrogen atmosphere concentration of the silicon nitride ceramic piece to be treated in the nitriding furnace body 1 is improved, the nitrogen directly acts on the surface of the silicon nitride ceramic piece to be treated, the temperature loss of the nitrogen is reduced, the nitriding effect and the nitriding speed are improved, and the nozzle 15 is circularly moved and reciprocally moved to cooperate with each other, so that the nitrogen is uniformly sprayed on the silicon nitride ceramic piece to be treated during the nitriding treatment, thereby further strengthening the nitriding effect.

[0072] It should be noted that when the rotating piece 5 rotates, the driving device 2 drives the rotating sleeve 6 to rotate at the same speed as the rotating piece 5 to offset the rotation of the transmission wheel 11 caused by the misalignment movement of the two. In detail, if the rotating piece 5 rotates, the rotating sleeve 6 is in the locked state, at this time, under the action of the third transmission chain 9, the second bevel gear rotates by a certain angle, and the first bevel gear drives the transmission wheel 11 to rotate by a certain angle. After the rotating piece 5 moves several times, the follower 13 is not at the end of the stroke.

[0073] Please refer to Figure 3 、 Figure 4 、 Figure 6 、 Figure 7 , the deflection assembly is connected with the lifting assembly and the nozzle 15, and the deflection assembly can deflect the nozzle 15 to the movement direction of the nozzle 15 when the nozzle 15 moves;

[0074] The deflection assembly comprises a rotating shaft 1501 rotatably installed on the follower 13 and connected with the nozzle 15, one deflection rod 17 is installed on each side of the rotating shaft 1501, and an abutting wheel 1701 is rotatably installed on the end of the deflection rod 17 away from the rotating center of the deflection rod 17. The upper trigger 19 and the lower trigger 18 arranged on the vertical plate 8 can cooperate with the abutting wheel 1701 to drive the rotating shaft 1501 to rotate;

[0075] The deflection assembly further comprises an energy storage structure arranged on the follower 13 and connected with the rotating shaft 1501, the energy storage structure comprises a containment sleeve 24 symmetrically arranged on the side wall of the follower 13, a connecting shaft 22 is slidably installed in the containment sleeve 24, and a pulley 21 is rotatably installed on the end of the connecting shaft 22 away from the containment sleeve 24;

[0076] The containment sleeve 24 further comprises a spring 23, one end of the spring 23 is connected with the inner wall of the containment sleeve 24, and the other end of the spring 23 is connected with the connecting shaft 22;

[0077] The energy storage structure further comprises a locking piece 20 matched with the pulley 21, the locking piece 20 is fixedly connected with the rotating shaft 1501, and two containing grooves 2001 are arranged on the locking piece 20, the two containing grooves 2001 are connected through two inclined surfaces 2002, and protruding portions are formed at the ends of the two inclined surfaces 2002 away from the containing grooves 2001, when the rotating shaft 1501 rotates, the pulley 21 can be switched from one containing groove 2001 to another containing groove 2001 through the two inclined surfaces 2002.

[0078] When the follower 13 moves upward, the nozzle 15 is in an upwardly inclined state, at this time, the nitrogen gas sprayed by the nozzle 15 will be inclined to act on the to-be-processed silicon nitride ceramic piece, in detail, when the nitrogen gas is inclined upward to act on the to-be-processed silicon nitride ceramic piece, the nitrogen gas will move upward from the impact point of the to-be-processed silicon nitride ceramic piece, at this time, the nitrogen gas close to the impact point will perform nitriding treatment on the to-be-processed silicon nitride ceramic piece, and the nitrogen gas far away from the impact point will perform pre-nitriding treatment on the to-be-processed silicon nitride ceramic piece due to temperature loss, and as the nozzle 15 rises, the to-be-processed silicon nitride ceramic piece will sequentially experience pre-nitriding treatment and nitriding treatment, thereby further improving the nitriding treatment effect, and the inclined spraying of the nitrogen gas improves the contact area between the nitrogen gas and the to-be-processed silicon nitride ceramic piece on the one hand, and improves the stability of the nitrogen gas flow on the other hand, avoids turbulence of the nitrogen gas in the nitriding furnace body 1, and compared with vertical spraying, the inclined spraying avoids the airflow when the nitrogen gas impacts the to-be-processed silicon nitride ceramic piece and moves reversely, avoids the outflow of the nozzle 15, reduces the load of the external nitrogen gas pump on the equipment, and the like.

[0079] Specifically, as shown in the accompanying drawings, Figure 6For example, when the nozzle 15 moves upward, the pulley 21 will be in engagement with the upper accommodation groove 2001, and the line between the center of the accommodation groove 2001 and the axis of the rotating shaft 1501 is on the extension line of the connecting shaft 22, so that the nozzle 15 can be kept in a stable state of tilting upward, and with the rising of the follower 13, the abutting wheel 1701 will abut against the upper trigger 19, and at this time, the abutting wheel 1701 will roll along the length direction of the upper trigger 19, and at the same time, the rotating shaft 1501 is driven to rotate through the deflection rod 17, so that the nozzle 15 changes the angle and drives the locking piece 20 to rotate, so that the pulley 21 is separated from the accommodation groove 2001 and moves along one of the inclined surfaces 2002 to the protruding part, and in this process, the spring 23 is compressed, and with the continuous rotation of the rotating shaft 1501, the pulley 21 will move over the protruding part, and at this time, the spring 23 will release the elastic potential energy to make the pulley 21 move along the other inclined surface 2002, and when the pulley 21 moves into the other accommodation groove 2001, the nozzle 15 realizes the angle flip, so that when the nozzle 15 moves downward, the nozzle 15 can tilt downward, so that the nitrogen gas can act on the silicon nitride ceramic piece to be processed, and when the nozzle 15 moves downward to the predetermined position, the abutting wheel 1701 can abut against the lower trigger 18 and drive the nozzle 15 to flip to tilt upward, so as to realize the automatic switching of the deflection angle of the nozzle 15, improve the automation degree of the equipment, and reduce the operation difficulty of the equipment.

[0080] Through the above arrangement, the deflection direction of the nozzle 15 can be automatically switched to the movement direction when the nozzle 15 moves, so that the nitrogen gas can act on the silicon nitride ceramic piece to be processed, and the silicon nitride ceramic piece to be processed can sequentially undergo pre-nitriding and nitriding, so as to further improve the nitriding effect, and the inclined injection of the nitrogen gas can improve the contact area between the nitrogen gas and the silicon nitride ceramic piece to be processed, and improve the stability of the nitrogen gas flow, avoid the turbulence of the nitrogen gas in the nitriding furnace body 1, and compared with the vertical injection, the inclined injection can avoid the airflow when the nitrogen gas impacts the silicon nitride ceramic piece to be processed and moves reversely, avoid the gas outlet of the nozzle 15 being blocked, and reduce the load of the external nitrogen gas pump to the equipment.

[0081] Please refer to Figure 5 , Figure 9 , the support assembly is connected with the supporting frame 701 and the rotating assembly, and two groups of top rods 30 are connected on the support assembly, and the two groups of top rods 30 can alternately lift the silicon nitride ceramic piece when the rotating assembly acts;

[0082] The support assembly comprises an outer top ring 28 and an inner top ring 29 which are concentric and have different diameters, the bottom of the outer top ring 28 is provided with a first fan-shaped abutting part 2801, and the bottom of the inner top ring 29 is provided with a second fan-shaped abutting part 2901, the first fan-shaped abutting part 2801 and the second fan-shaped abutting part 2901 are arranged in a staggered manner;

[0083] The support assembly further comprises a follower roller 32 which is rotatably installed on the rotating member 5 and is adapted to the first fan-shaped abutting part 2801 and the second fan-shaped abutting part 2901.

[0084] In the initial state, the follower roller 32 is in abutment with the first fan-shaped abutting part 2801 and the second fan-shaped abutting part 2901, at this time, the inner top ring 29 is at the same height as the top rods 30 on the outer top ring 28, and the stability is better when the silicon nitride ceramic piece to be treated is placed on the top rods 30, in use, due to the staggered arrangement of the first fan-shaped abutting part 2801 and the second fan-shaped abutting part 2901, when the rotating member 5 rotates to drive the follower roller 32 to move in a circular motion, the follower roller 32 will cooperate with the first fan-shaped abutting part 2801 (the second fan-shaped abutting part 2901) to lift the outer top ring 28 (the inner top ring 29) upward, at this time, only one group of top rods 30 acts on the bottom of the silicon nitride ceramic piece to be treated to lift it up, with the rotation of the rotating member 5, the follower roller 32 will separate from the first fan-shaped abutting part 2801 (the second fan-shaped abutting part 2901), at this time, the outer top ring 28 (the inner top ring 29) will move downward and drive the top rods 30 in abutment with the bottom of the silicon nitride ceramic piece to be treated to move downward, at the same time, the follower roller 32 will cooperate with the second fan-shaped abutting part 2901 (the first fan-shaped abutting part 2801) to lift the inner top ring 29 (the outer top ring 28) upward and make the other group of top rods 30 lift upward, that is, when the rotating member 5 rotates, it will alternately act on the first fan-shaped abutting part 2801 and the second fan-shaped abutting part 2901, and the two groups of top rods 30 will alternately act on the bottom of the silicon nitride ceramic piece to be treated to lift it up, and due to the concentricity and different diameters of the outer top ring 28 and the inner top ring 29, the positions of the two groups of top rods 30 acting on the bottom of the silicon nitride ceramic piece to be treated are different, so that the bottom of the silicon nitride ceramic piece to be treated can also be subjected to nitriding treatment without being blocked during the nitriding treatment of the silicon nitride ceramic piece, compared with the existing nitriding treatment furnace, the range of treatment is larger when the silicon nitride ceramic piece is treated, and the nitriding of the bottom of the silicon nitride ceramic piece is avoided due to blocking.

[0085] Through the above setting, when the follower roller 32 follows the rotation piece 5 to do the circular motion, it can alternately act on the first fan-shaped abutting piece 2801 and the second fan-shaped abutting piece 2901, so that the outer top ring 28 and the inner top ring 29 are alternately lifted, thereby the two groups of top rods 30 are alternately lifted, so as to switch the lifting position when the silicon nitride ceramic piece is lifted, and the bottom of the silicon nitride ceramic piece can also be well nitrided during the nitriding process, compared with the existing nitriding furnace, the range of the treatment is larger when the silicon nitride ceramic piece is treated, and the bottom of the silicon nitride ceramic piece is avoided from being insufficiently nitrided due to shielding.

[0086] A method for treating the silicon nitride ceramic piece using the nitriding furnace, comprising the following steps:

[0087] Step one: pipeline connection is made between the external nitrogen gas pumping equipment and the nitriding furnace body 1;

[0088] Step two: the upper cover of the nitriding furnace body 1 is lifted, the silicon nitride ceramic piece to be treated is placed on the supporting frame 701, the central axis of the silicon nitride ceramic piece to be treated is aligned with the key center line of the supporting frame 701, then the upper cover of the nitriding furnace body 1 is reset and sealed by screwing;

[0089] Step three: the external nitrogen gas pumping equipment is started, and the cross drive mechanism is started, when the cross drive mechanism works, the nozzle 15 will be sequentially driven to do reciprocating motion along the vertical direction of space and stepwise circular motion along the central axis of the silicon nitride ceramic piece to be treated, so that the nitrogen gas is uniformly sprayed on the silicon nitride ceramic piece to be treated;

[0090] Step four: when the nozzle 15 moves upward, the nozzle 15 will be in an inclined upward state, when the nozzle 15 moves downward, the nozzle 15 will be in an inclined downward state, and the nitrogen gas is inclined to the silicon nitride ceramic piece to be treated;

[0091] Step five: with the movement of the rotating assembly, the two groups of top rods 30 on the supporting assembly will be alternately lifted to switch the abutting position of the top rod 30 on the silicon nitride ceramic piece to be treated;

[0092] Step six: the above steps three to five are repeated, and the silicon nitride ceramic piece is taken out after about 10-15h, and the nitriding treatment is completed.

[0093] It will be obvious to a person skilled in the art that the application is not limited to the details of the foregoing exemplary embodiments and can be implemented in other concrete forms without departing from the spirit or essential characteristics of the application. The embodiments are therefore to be considered in all respects as illustrative and not restrictive, the scope of the application being indicated by the appended claims rather than by the foregoing description, and all changes which come within the meaning and range of equivalency of the claims are therefore intended to be embraced therein. No reference signs in the claims should be considered as limiting the scope of the claims to the identity of the reference signs therein.

[0094] Furthermore, it should be understood that although the description is made on the basis of the embodiments, not every embodiment contains only one independent technical solution, and the description of the specification is only for the sake of clarity, and those skilled in the art should consider the specification as a whole, and the technical solutions in each embodiment can also be appropriately combined to form other embodiments that those skilled in the art can understand.

Claims

1. A nitriding furnace for silicon nitride ceramic parts, comprising: A nitriding furnace body (1), wherein a support frame (701) for carrying a silicon nitride ceramic piece is provided in the nitriding furnace body (1); A nozzle (15) is arranged in the nitriding furnace body (1), and the nozzle (15) is capable of blowing heated nitrogen toward the side of the silicon nitride ceramic piece; Characterized in that the nitriding treatment furnace further comprises: A cross drive mechanism is installed in the nitriding furnace body (1), the cross drive mechanism includes a rotating assembly and a plurality of lifting assemblies, the lifting assemblies are connected to the nozzle (15), and the lifting assemblies and the rotating assemblies are alternately matched to enable the nozzle (15) to intermittently rotate along the circumferential direction of the silicon nitride ceramic piece and reciprocate along the longitudinal direction of the silicon nitride ceramic piece; a deflection assembly connected to the lifting assembly and the nozzle (15), wherein the deflection assembly is capable of deflecting the nozzle (15) in its movement direction when the nozzle (15) moves; A support assembly connected to the support bracket (701) and the rotating assembly, wherein two groups of push rods (30) are connected to the support assembly, and the two groups of push rods (30) are capable of alternately lifting the silicon nitride ceramic piece when the rotating assembly is in motion; The rotating assembly comprises a rotating member (5) rotatably mounted on the nitriding furnace body (1), the rotating shaft of the rotating member (5) is a hollow structure, and a rotating sleeve (6) is rotatably mounted inside the rotating shaft of the rotating member (5), and the supporting frame (701) is fixedly connected to the nitriding furnace body (1) via a vertical shaft (7) penetrating the rotating sleeve (6); The rotating assembly further comprises a driving device (2) arranged at the bottom of the nitriding furnace body, wherein the driving device (2) is connected to the rotating sleeve (6) via a first transmission chain (3) and is connected to the rotating member (5) via a second transmission chain (4); The multiple lifting components are connected via a fourth transmission chain (31); The lifting assembly comprises a vertical plate (8) arranged perpendicular to the rotating member (5); two transmission wheels (11) are rotatably mounted on the vertical plate (8); a connecting chain (12) is sleeved between the two transmission wheels (11); The lifting assembly further comprises a follower (13) provided on the vertical plate (8), the follower (13) being connected to the nozzle (15), and the follower (13) being connected to the connecting chain (12) via a chimeric structure; A bevel gear set (10) is also provided on the vertical plate (8), and the bevel gear set (10) is connected to one of the transmission wheels (11), and the bevel gear set (10) is connected to the rotating sleeve (6) via a third transmission chain (9).

2. A nitriding furnace for silicon nitride ceramic parts according to claim 1, characterized in that: The interlocking structure comprises an interlocking wheel (1201) rotatably mounted on the connecting chain (12) and an interlocking groove (1301) formed on the follower (13), wherein the interlocking wheel (1201) is capable of rolling in the interlocking groove (1301); Slide grooves (801) are provided on both sides of the vertical plate (8) along the length direction thereof, and a slider (14) mounted on the follower (13) is capable of sliding in the slide grooves (801).

3. The nitriding furnace for silicon nitride ceramic parts according to claim 1, characterized in that: The deflection assembly comprises a rotating shaft (1501) rotatably mounted on the follower (13) and connected to the nozzle (15), a deflection rod (17) being mounted on each side of the rotating shaft (1501), an abutment wheel (1701) being rotatably mounted on one end of the deflection rod (17) away from its rotation center, and an upper triggering member (19) and a lower triggering member (18) arranged on the vertical plate (8) being capable of cooperating with the abutment wheel (1701) to drive the rotating shaft (1501) to rotate; The deflection assembly further comprises an energy storage structure arranged on the follower (13) and connected to the rotating shaft (1501).

4. A nitriding furnace for silicon nitride ceramic parts according to claim 3, characterized in that: The energy storage structure comprises a hysteresis sleeve (24) symmetrically arranged on the side wall of the follower (13), a connecting shaft (22) being slidably mounted in the hysteresis sleeve (24), and a pulley (21) being rotatably mounted on one end of the connecting shaft (22) away from the hysteresis sleeve (24); A spring (23) is further provided in the hysteresis sleeve (24), one end of the spring (23) is connected to the inner wall of the hysteresis sleeve (24), and the other end is connected to the connecting shaft (22); The energy storage structure further includes a locking member (20) adapted to the pulley (21).

5. A nitriding furnace for silicon nitride ceramic parts according to claim 4, characterized in that: The locking member (20) is fixedly connected to the rotating shaft (1501), and two retardation grooves (2001) are provided on the locking member (20), the two retardation grooves (2001) are connected via two inclined surfaces (2002), and a protrusion is formed at one end of the two inclined surfaces (2002) away from the retardation grooves (2001); When the rotating shaft (1501) rotates, the pulley (21) can be switched from one of the retardation grooves (2001) to the other retardation groove (2001) via the two inclined surfaces (2002).

6. The nitriding furnace for silicon nitride ceramic parts according to claim 5, characterized in that: The interior of the rotating shaft (1501) is in communication with the nozzle (15), and a plurality of through slots (1502) are provided on the rotating shaft (1501); An annular connector (16) covering the through groove (1502) is also installed on the rotating shaft (1501) in a sealed and rotatable manner. The annular connector (16) is connected to an inner sleeve (26) fixed on the vertical plate (8) through a connecting pipe (25). The inner sleeve (26) is sealed and rotatably connected to an outer sleeve (27) fixed in the nitriding furnace body (1).

7. The nitriding furnace for silicon nitride ceramic parts according to claim 1, characterized in that: The support assembly comprises an outer top ring (28) and an inner top ring (29) which are concentric and have different diameters, wherein a first fan-shaped abutment (2801) is provided at the bottom of the outer top ring (28), and a second fan-shaped abutment (2901) is provided at the bottom of the inner top ring (29), and the first fan-shaped abutment (2801) and the second fan-shaped abutment (2901) are staggered. The support assembly further comprises a follower roller (32) rotatably mounted on the rotating member (5) and adapted to the first sector-shaped abutment member (2801) and the second sector-shaped abutment member (2901).

8. A method for treating a silicon nitride ceramic part using the nitriding furnace according to claim 1, characterized in that: The following steps are involved: Step 1: Connect the external nitrogen pump to the equipment and the nitriding furnace body (1) through pipelines; Step 2: Lift the upper cover of the nitriding furnace body (1), and place the silicon nitride ceramic piece to be processed on the support frame (701), while aligning the central axis of the silicon nitride ceramic piece to be processed with the central center line of the support frame (701), and then reset the upper cover of the nitriding furnace body (1) and tighten it with bolts to seal it; Step 3: Start the external nitrogen pump to the equipment and start the cross drive mechanism at the same time. When the cross drive mechanism is working, it will drive the nozzle (15) to perform reciprocating motion in the vertical direction of the space and to perform stepping circular motion along the central axis of the silicon nitride ceramic piece to be processed, so that the nitrogen is evenly sprayed on the silicon nitride ceramic piece to be processed; Step 4: When the nozzle (15) moves upward, the nozzle (15) will be in an upward tilted state, and when the nozzle (15) moves downward, the nozzle (15) will be in a downward tilted state, and the nitrogen gas will be sprayed obliquely onto the silicon nitride ceramic part to be processed; Step 5: As the rotating assembly moves, the two sets of push rods (30) on the supporting assembly are alternately lifted to switch the abutment positions of the push rods (30) on the silicon nitride ceramic piece to be processed; Step 6: Repeat steps 3 to 5 above for 10 to 15 hours, then remove the silicon nitride ceramic part to complete the nitriding process.

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