CN211651079U

CN211651079U - Heated air circulation oven

Info

Publication number: CN211651079U
Application number: CN202020233456.3U
Authority: CN
Inventors: 陈岩; 韩晓杰; 王宪; 霍冰冰
Original assignee: Beijing Hongji Pharmaceutical Co ltd
Current assignee: Beijing Hongji Pharmaceutical Co ltd
Priority date: 2020-02-28
Filing date: 2020-02-28
Publication date: 2020-10-09
Anticipated expiration: 2030-02-28

Abstract

The utility model discloses a heated air circulation oven, including the stoving case, the lateral surface fixed mounting of stoving case has control panel, the internally mounted of stoving case has the hot plate, hot plate and control panel electricity are connected, the inside of stoving case is provided with a plurality of racks that are used for placing the medicinal material, and is a plurality of the rack is the array and distributes, rack and stoving case rotate to be connected, the stoving case is provided with the slewing mechanism who is used for driving the rack upset, slewing mechanism includes the axis of rotation of vertical setting, axis of rotation and rack pass through the upset of drive assembly drive rack, slewing mechanism is still including being used for driving axis of rotation pivoted motor, motor and control panel electricity are connected. It has the advantage that prevents to shelter from each other between the medicinal material and cover, makes the medicinal material be heated evenly.

Description

Heated air circulation oven

Technical Field

The utility model relates to a miscellaneous traditional chinese medicine production technical field, in particular to heated air circulation oven.

Background

When the traditional Chinese medicine is prepared, the medicinal materials need to be dried so as to ensure that the medicinal materials can be used in the next process. At present, the medicinal materials are dried by a hot air circulation oven.

Current grant publication number is CN 209960869U's patent document discloses a traditional chinese medicine tablet heated air circulation oven, including oven body and heater, the chamber door is installed through the articulated chamber door that installs of stainless steel hinge in the relative both sides of oven body, oven body internally mounted has the thing otter board of carrying, oven body one side is through circulation tuber pipe and circulating fan's input intercommunication, circulating fan's output passes through circulation tuber pipe and heater intercommunication, the heater passes through circulation tuber pipe and the inside fan housing intercommunication of oven body, the fan housing passes through adjustment mechanism fixed mounting at oven body top, the internally mounted of heater has the electric heating board, the output intercommunication of tuber pipe and fan is passed through to one side bottom of heater.

Although the traditional Chinese medicine tablet hot air circulation drying oven realizes the drying treatment of the circulating hot air of the traditional Chinese medicine tablets by matching the drying oven body, the circulating fan and the heater, the energy consumption and the cost are reduced, the adjusting structure is arranged to be matched with the fan cover, the circulating wind direction is changed, and the drying effect is improved.

However, it can be seen from the drawings in the specification that the circulating fan is arranged on the top wall of the oven body, when the traditional Chinese medicine tablets are required to be dried, the traditional Chinese medicine tablets are placed on the carrying net plate, the air is conveyed to the oven through the circulating fan to dry the traditional Chinese medicine tablets on the carrying net plate, because the carrying net plate inside the oven body is provided with a plurality of layers, and the distance between two adjacent carrying net plates is the same, the air conveyed out from the circulating fan is contacted with the medicinal material tablets on the upper surface of the carrying net plate, the medicinal material tablets on the carrying net plate are contacted with each other and are tightly attached together, the medicinal material tablets are mutually covered and shielded, so that a blind area exists when the air blown out from the circulating fan is dried on the medicinal material tablets, the medicinal material tablets are not uniformly dried, the quality.

SUMMERY OF THE UTILITY MODEL

Not enough to prior art exists, the utility model aims to provide a heated air circulation oven, it has prevents to shelter from each other between the medicinal material and covers, makes the medicinal material be heated even advantage.

The above technical purpose of the present invention can be achieved by the following technical solutions:

the utility model provides a heated air circulation oven, includes the stoving case, the lateral surface fixed mounting of stoving case has control panel, the internally mounted of stoving case has the hot plate, hot plate and control panel electricity are connected, the inside of stoving case is provided with a plurality of racks that are used for placing the medicinal material, and is a plurality of the rack is the array and distributes, rack and stoving case rotate to be connected, the stoving case is provided with the slewing mechanism who is used for driving the rack upset, slewing mechanism includes the axis of rotation of vertical setting, axis of rotation and rack pass through the upset of drive assembly drive rack, slewing mechanism is still including being used for driving axis of rotation pivoted motor, motor and control panel electricity are connected.

Through adopting above-mentioned technical scheme, when needing to dry the medicinal material, put into the rack with the medicinal material on, open the switch of hot plate through control panel, open the hot plate, make the inside temperature of stoving incasement portion rise under the effect of hot plate, starter motor, the motor drives the axis of rotation and rotates, the axis of rotation passes through the upset of drive assembly drive rack, the rack drives the medicinal material in the in-process upset of rack at the upset, increase the area of contact of medicinal material and the inside hot-air of stoving incasement portion, improve the air flow between the medicinal material, thereby prevent to shelter from the cover each other between the medicinal material, make the medicinal material be heated evenly.

The utility model discloses further set up to: the transmission assembly comprises a limiting column, a rotating groove is formed in the limiting column, the limiting column is sleeved outside the rotating shaft, the limiting column is fixedly connected with the drying box, a track groove is formed in the rotating shaft, a moving member is arranged in the track groove, one end, far away from the rotating shaft, of the moving member penetrates through the limiting column, and the moving member and the placing frame are detachably connected.

Through adopting above-mentioned technical scheme, starter motor, motor drive axis of rotation rotates, and the axis of rotation drives the moving member along the motion of track groove, because the one end that the axis of rotation was kept away from to the moving member runs through spacing post, spacing post and stoving case fixed connection to avoid the synchronous rotation of moving member and axis of rotation, realize the rotation of moving member, the moving member drives the synchronous rotation of rack, thereby realizes the upset of rack.

The utility model discloses further set up to: the moving member includes first connecting rod and second connecting rod and sets up the third connecting rod between first connecting rod and second connecting rod, first connecting rod and second connecting rod parallel arrangement, and first connecting rod and second connecting rod set up respectively in the both sides of third connecting rod, the one end of first connecting rod is pegged graft in orbit groove, the other end and third connecting rod fixed connection, the one end and the third connecting rod fixed connection of second connecting rod, the other end run through behind spacing post and the rack can dismantle the connection through spacing subassembly.

Through adopting above-mentioned technical scheme, axis of rotation pivoted in-process, moving member are under the effect of spacing post, and the tip of first connecting rod is the orbit motion along the orbit groove of axis of rotation, sets up first connecting rod and second connecting rod respectively in the both sides of third connecting rod, is convenient for convert the orbit motion of first connecting rod into the rotation of second connecting rod, and the second connecting rod drive rack of being convenient for overturns.

The utility model discloses further set up to: the limiting assembly comprises a sleeve and an inner rod which are arranged on the placing frame, the sleeve and the inner rod are sleeved, one end, away from the placing frame, of the sleeve is provided with a limiting inner convex ring, and the sleeved end of the inner rod and the sleeve is provided with a limiting outer convex ring; be provided with compression spring between interior pole and the sleeve pipe diapire, when compression spring was in natural state, the sheathed tube one end was kept away from to interior pole cup jointed with the second connecting rod, spacing subassembly still including keeping the fixed dead lever of pole and second connecting rod relative position in the pole.

Through adopting above-mentioned technical scheme, to the one side removal interior pole that is close to the rack, interior pole extrusion compression spring, compression spring is in unnatural state, makes the setting of interior pole not hinder the connection between rack and the second connecting rod, when interior pole and second connecting rod are in a straight line, removes the control to interior pole, and the home position is replied in to compression spring drive interior pole, when interior pole keeps away from sheathed tube one end and second connecting rod and cup joints, realizes the fixed connection of interior pole and second connecting rod through the dead lever.

The utility model discloses further set up to: the telescopic inside is provided with the guide bar, the outside of guide bar is located to the compression spring cover, and when compression spring was in the unnatural state, the outside of guide bar was located to interior pole cover.

By adopting the technical scheme, the guide rod is arranged, so that on one hand, the compression spring is prevented from generating non-transverse elastic deformation in the process of extruding the compression spring by the inner rod; on the other hand, the guide effect is provided for the movement of the inner rod, and the sleeving of the inner rod and the second connecting rod is convenient to realize.

The utility model discloses further set up to: the rack is provided with the dwang, the rotation hole has been seted up to the inner wall of stoving case, the dwang is pegged graft and is rotated and connect in rotating the hole, dwang and sleeve pipe set up relatively.

Through adopting above-mentioned technical scheme, when needs installation rack, peg graft the dwang in the inside in rotation hole, the other end passes through spacing subassembly and second connecting rod and connects, is convenient for realize the connection dismantled of rack and stoving case. The rotating rod and the rotating hole are connected, so that the rack can be conveniently placed in the drying box to be turned.

The utility model discloses further set up to: the rack is including having upper end open-ended place the frame and covering and locate and place frame upper end open-ended shrouding, the shrouding can be dismantled with placing the frame and connect.

Through adopting above-mentioned technical scheme, place the medicinal material in the inside of placing the frame, the lid closes the shrouding, places the upper end opening of frame through the shrouding shutoff, prevents that the medicinal material from deviating from at rack pivoted in-process.

The utility model discloses further set up to: the placing frame is provided with an insertion port at an upper end opening, the sealing plate is fixedly provided with an insertion block, the insertion block is inserted into the insertion port, one side of the sealing plate, which is far away from the insertion block, is fixedly provided with an elastic clamping block, the placing frame is provided with a clamping groove matched with the elastic clamping block, and the elastic clamping block is clamped in the clamping groove.

Through adopting above-mentioned technical scheme, be convenient for realize the shrouding and place the frame can dismantle the connection.

The utility model discloses further set up to: a plurality of air holes are formed in the placing frame and the sealing plate.

Through adopting above-mentioned technical scheme, through setting up the bleeder vent, the inside hot-air admission of the incasement portion of being convenient for of drying places the inside of frame, realizes the stoving to placing the inside medicinal material of frame.

The utility model discloses further set up to: a fan is arranged in the drying box and electrically connected with the control panel.

Through adopting above-mentioned technical scheme, start the fan, through the setting of fan, the flow of the inside air of stoving incasement portion is accelerated, is convenient for improve the inside temperature of stoving incasement portion fast, is convenient for dry the medicinal material.

To sum up, the utility model discloses following beneficial effect has: open the switch of hot plate through control panel, open the hot plate, make the temperature of stoving incasement portion rise under the effect of hot plate, starter motor, the motor drives the axis of rotation and rotates, the axis of rotation passes through the upset of transmission assembly drive rack, the rack drives the medicinal material in the inside upset of rack at the in-process of upset, increase the area of contact of medicinal material and stoving incasement portion hot-air, improve the air flow between the medicinal material, thereby prevent to shelter from each other between the medicinal material and cover, make the medicinal material be heated evenly.

Drawings

Fig. 1 is a schematic view of the overall structure of an embodiment of the present invention;

fig. 2 is a schematic view of the overall structure of the embodiment of the present invention;

fig. 3 is a schematic structural view of a rack according to an embodiment of the present invention;

fig. 4 is an exploded view of a rack according to an embodiment of the present invention;

FIG. 5 is a top view of FIG. 1;

FIG. 6 is a sectional view taken along line A-A of FIG. 5;

FIG. 7 is an enlarged view of portion B of FIG. 6;

fig. 8 is a schematic view of the connection relationship among the placement frame, the rotation shaft, and the rotation mechanism according to the embodiment of the present invention.

In the figure, 1, a drying box; 11. a top plate; 12. a base plate; 13. fixing the side plate; 131. a vertical mounting groove; 14. a rear side plate; 2. a cabinet door; 21. a handle; 3. heating plates; 4. a fan; 5. a control panel; 6. placing a rack; 61. placing the frame; 611. air holes are formed; 612. an interface; 613. a clamping groove; 62. closing the plate; 621. an insertion block; 622. an elastic clamping block; 7. rotating the rod; 8. a rotating mechanism; 81. a rotating shaft; 811. a track groove; 8111. a first transverse groove; 8112. a chute; 8113. a second transverse groove; 82. a motor; 83. a transmission assembly; 831. a limiting column; 8311. a rotating groove; 832. a moving member; 8321. a first link; 8322. a second link; 8323. a third link; 9. a limiting component; 91. a sleeve; 911. a limiting inner convex ring; 92. an inner rod; 921. a limiting convex ring; 93. a compression spring; 94. fixing the rod; 10. a guide rod.

Detailed Description

The present invention will be described in further detail with reference to the accompanying drawings.

Combine fig. 1 and fig. 2, do the utility model discloses a heated air circulation oven, including stoving case 1, stoving case 1 includes a roof 11, a bottom plate 12 and two fixed curb plates 13 and a posterior lateral plate 14, and the front side of stoving case 1 is opened and is equipped with the mouth of putting goods, puts the relative setting of mouth of putting goods and posterior lateral plate 14. The drying box 1 is provided with a push-and-pull cabinet door 2 at the goods placing opening, and the front side of the cabinet door 2 is provided with a handle 21.

The heating plate 3 is all installed to the inner wall of stoving case 1 rear side board 14 and the lower surface of roof 11, and two fans 4 are installed to the upper surface of stoving case 1 bottom plate 12, and two fans 4 set up in the upper surface interval of stoving case 1 bottom plate 12. The outside fixed surface of stoving case 1 installs control panel 5, and hot plate 3 and fan 4 all are connected with control panel 5 electricity.

The internally mounted of stoving case 1 has a plurality of racks 6 that are used for placing the medicinal material, and a plurality of racks 6 set up along the length direction interval of stoving case 1, and it has the space of rotating that supplies rack 6 pivoted to reserve between the adjacent rack 6.

Referring to fig. 3 and 4, the placement frame 6 includes a placement frame 61 having an upper opening, and a cover plate 62 covering the upper opening of the placement frame 61, wherein the cover plate 62 is detachably connected to the placement frame 61. The placing frame 61 and the closing plate 62 are both provided with a plurality of air holes 611.

Two inserting ports 612 are formed in the opening at the upper end of the placing frame 61 close to the rear side plate 14 of the drying box 1, two inserting blocks 621 are welded on the lower surface of the sealing plate 62, and the inserting blocks 621 are inserted into the inserting ports 612. One side of the sealing plate 62 far from the insertion block 621 is fixedly provided with an elastic clamping block 622, the front side of the placing frame 61 is provided with a clamping groove 613 matched with the elastic clamping block 622, and the elastic clamping block 622 is clamped in the clamping groove 613.

Referring to fig. 5 and 6, the placing frame 61 is rotatably connected to the drying box 1. Place frame 61 and be the rectangle setting, place frame 61 and weld dwang 7 towards one side of the fixed curb plate 13 in stoving case 1 right side, be located the fixed curb plate 13 on stoving case 1 right side and seted up the rotation hole, dwang 7 pegs graft and rotate to be connected in rotating the hole.

Referring to fig. 6 and 7, the drying box 1 is provided with a rotation mechanism 8 (see fig. 8) for driving the rack 6 to turn. The rotating mechanism 8 includes a rotating shaft 81, a motor 82 for driving the rotating shaft 81 to rotate, and a transmission assembly 83.

Vertical mounting groove 131 has been seted up to fixed curb plate 13 that is located stoving case 1 left side, and axis of rotation 81 is vertical to be set up in the inside of vertical mounting groove 131, and motor 82 installs in the diapire of vertical mounting groove 131, the lower extreme fixed connection of the output of motor 82 and axis of rotation 81, and axis of rotation 81 and the coaxial rotation of motor 82, motor 82 and control panel 5 electricity are connected.

The transmission assembly 83 includes a limiting column 831 and a moving member 832, and the moving member 832 corresponds to the placing frame 61. The rotation groove 8311 is formed in the limiting column 831, the rotation groove 8311 is arranged along the length direction of the limiting column 831, the limiting column 831 is sleeved outside the rotation shaft 81, and the limiting column 831 is rotatably connected with the rotation shaft 81. The outer circumferential wall of the limiting column 831 is welded to the inner circumferential wall of the vertical mounting groove 131.

Referring to fig. 8, a track groove 811 is formed in the outer peripheral wall of the rotating shaft 81, the track groove 811 includes a first transverse groove 8111 and two diagonal grooves 8112, the two diagonal grooves 8112 are disposed on the same side of the first transverse groove 8111, the inclination directions of the two diagonal grooves 8112 are opposite, one end of each diagonal groove 8112, which is far away from the first transverse groove 8111, is communicated with a second transverse groove 8113, the first transverse groove 8111 and the second transverse groove 8113 are arranged in parallel, the end portions of the two second transverse grooves 8113 are communicated, and the distance between the ends, which are far away from the first transverse groove 8111, of the two diagonal grooves 8112 is greater than the distance between the two diagonal grooves 8112, which are close to the first.

Referring to fig. 7, the moving member 832 is slidably connected to the inside of the track groove 811, the moving member 832 includes a first link 8321, a second link 8322, and a third link 8323 disposed between the first link 8321 and the second link 8322, the first link 8321 and the second link 8322 are disposed in parallel, the first link 8321 and the second link 8322 are disposed on different sides of the third link 8323, respectively, and the first link 8321, the second link 8322, and the third link 8323 form a zigzag shape.

Referring to fig. 7 and 8, one end of the first link 8321 is inserted into the track groove 811, the other end is welded to the third link 8323, and one end of the second link 8322 is welded to the third link 8323. When the first connecting rod 8321 moves to the inclined groove 8112 through the first transverse groove 8111 or the second transverse groove 8113, the second connecting rod 8322 rotates around the axis of the second connecting rod 8322, and one end of the second connecting rod 8322, which is far away from the third connecting rod 8323, penetrates through the limiting column 831 and is detachably connected with the placing frame 6 through the limiting assembly 9.

The position limiting assembly 9 comprises a sleeve 91, an inner rod 92, a compression spring 93 and a fixing rod 94.

The sleeve 91 is welded on one side of the placing frame 61 close to the fixed side plate 13 of the drying box 1, and the sleeve 91 and the rotating rod 7 are oppositely arranged. The sleeve 91 is hollow, and the inner rod 92 is inserted into the sleeve 91. The one end integrated into one piece that the frame 61 was kept away from to the sleeve pipe 91 has the spacing interior bulge loop 911 that prevents interior pole 92 and deviate from, and the end integrated into one piece that cup joints of interior pole 92 and sleeve pipe 91 has spacing outer bulge loop 921, and the periphery wall butt of spacing outer bulge loop 921 is in the internal perisporium of sleeve pipe 91. The inner rod 92 is provided with a through hole at the center, the through hole is arranged along the length direction of the inner rod 92, and one end of the second connecting rod 8322, which is far away from the third connecting rod 8323, is inserted into the through hole. The second connecting rod 8322 is provided with a second threaded hole at the overlapping position of the second connecting rod 8322 and the inner rod 92, the inner rod 92 is provided with a first threaded hole, the first threaded hole and the second threaded hole are positioned on the same straight line, and the end part of the fixing rod 94 penetrates through the first threaded hole and then is in threaded connection with the second threaded hole. One end of the compression spring 93 is welded with the limit outward convex ring 921, and the other end is fixedly connected with the placing frame 61.

Place frame 61 welding and have guide bar 10, guide bar 10 sets up in the inside of sleeve pipe 91, and the outside of guide bar 10 is located to compression spring 93 cover, and when compression spring 93 was in the natural state, interior pole 92 kept away from the one end and the second connecting rod of sleeve pipe 91 cup jointed, the tip and the guide bar 10 butt of second connecting rod. When the compression spring 93 is in an unnatural state, the limiting outward protruding ring 921 acts on the compression spring 93, and the inner rod 92 is sleeved outside the guide rod 10.

The implementation principle of the embodiment is as follows: the medicinal materials are placed inside the placing frame 61, the sealing plate 62 is covered to form the sealed placing frame 6, one end of the placing frame 6 is inserted into the rotating hole, the inner rod 92 is moved to one side close to the placing frame 6, the inner rod 92 extrudes the compression spring 93, the compression spring 93 is in an unnatural state, the arrangement of the inner rod 92 does not interfere with the connection between the placing frame 6 and the second connecting rod 8322, when the inner rod 92 and the second connecting rod 8322 are positioned on the same straight line, the control over the inner rod 92 is released, the compression spring 93 drives the inner rod 92 to return to the original position, and the fixed connection of the inner rod 92 and the second connecting rod is realized through the fixing rod 94; the cabinet door 2 is closed, the heating plate 3 and the fan 4 are opened through the control panel 5, the temperature inside the drying box 1 is increased, the motor 82 is started, the motor 82 drives the rotating shaft 81 to rotate, the rotating shaft 81 drives the moving member 832 to move along the track groove 811, when the first connecting rod 8321 moves to the inclined groove 8112 through the first transverse groove 8111 or the second transverse groove 8113, the second connecting rod 8322 rotates by taking the axis of the second connecting rod 8322 as the center, and the placing frame 61 is connected with the second connecting rod 8322 through the fixing rod 94, the placing frame 61 is driven to rotate by the second connecting rod 8322, and therefore the placing frame 61 is turned over. The rack 6 drives the medicinal material in the inside upset of rack 6 at the in-process of upset, and the area of contact of increase medicinal material and the 1 inside hot-air of stoving case improves the air flow between the medicinal material to prevent to shelter from each other between the medicinal material and cover, make the medicinal material be heated evenly.

The embodiment of this specific implementation mode is the preferred embodiment of the present invention, not limit according to this the utility model discloses a protection scope, so: all equivalent changes made according to the structure, shape and principle of the utility model are covered within the protection scope of the utility model.

Claims

1. A hot air circulation oven comprises a drying box (1), a control panel (5) is fixedly mounted on the outer side surface of the drying box (1), a heating plate (3) is mounted inside the drying box (1), the heating plate (3) is electrically connected with the control panel (5), and the hot air circulation oven is characterized in that a plurality of placing frames (6) used for placing medicinal materials are arranged inside the drying box (1), the placing frames (6) are distributed in an array manner, the placing frames (6) are rotatably connected with the drying box (1), the drying box (1) is provided with a rotating mechanism (8) used for driving the placing frames (6) to turn over, the rotating mechanism (8) comprises a vertically arranged rotating shaft (81), the rotating shaft (81) and the placing frames (6) drive the placing frames (6) to turn over through a transmission assembly (83), the rotating mechanism (8) further comprises a motor (82) used for driving the rotating shaft (81) to rotate, the motor (82) is electrically connected with the control panel (5).

2. The hot air circulation oven according to claim 1, wherein the transmission assembly (83) comprises a limiting column (831), a rotating groove (8311) is formed in the limiting column (831), the limiting column (831) is sleeved outside the rotating shaft (81), the limiting column (831) is fixedly connected with the drying box (1), a track groove (811) is formed in the rotating shaft (81), a moving member (832) is arranged in the track groove (811), one end, far away from the rotating shaft (81), of the moving member (832) penetrates through the limiting column (831), and the moving member (832) is detachably connected with the placing frame (6).

3. The hot air circulation oven according to claim 2, wherein the moving member (832) comprises a first connecting rod (8321), a second connecting rod (8322) and a third connecting rod (8323) arranged between the first connecting rod (8321) and the second connecting rod (8322), the first connecting rod (8321) and the second connecting rod (8322) are arranged in parallel, the first connecting rod (8321) and the second connecting rod (8322) are respectively arranged on two sides of the third connecting rod (8323), one end of the first connecting rod (8321) is inserted into the track groove (811), the other end of the first connecting rod (8321) is fixedly connected with the third connecting rod (8323), one end of the second connecting rod (8322) is fixedly connected with the third connecting rod (8323), and the other end of the second connecting rod (8322) penetrates through the limiting column (831) and is detachably connected with the placing rack (6) through the limiting assembly (9).

4. The hot air circulation oven according to claim 3, wherein the limiting assembly (9) comprises a sleeve (91) and an inner rod (92) which are arranged on the placing rack (6), the sleeve (91) and the inner rod (92) are sleeved, one end of the sleeve (91) far away from the placing frame (61) is provided with an inner limiting convex ring (911), and the sleeved ends of the inner rod (92) and the sleeve (91) are provided with an outer limiting convex ring (921); be provided with compression spring (93) between interior pole (92) and sleeve pipe (91) diapire, when compression spring (93) were in natural state, interior pole (92) were kept away from the one end and the second connecting rod of sleeve pipe (91) and are cup jointed, spacing subassembly (9) still including keeping interior pole (92) and fixed dead lever (94) of second connecting rod relative position.

5. The hot air circulation oven according to claim 4, characterized in that the sleeve (91) is provided with a guide rod (10) inside, the compression spring (93) is sleeved outside the guide rod (10), and the inner rod (92) is sleeved outside the guide rod (10) when the compression spring (93) is in an unnatural state.

6. The heated air circulation oven according to claim 5, characterized in that the placing rack (6) is provided with a rotating rod (7), the inner wall of the drying box (1) is provided with a rotating hole, the rotating rod (7) is inserted and rotatably connected to the rotating hole, and the rotating rod (7) and the sleeve (91) are oppositely arranged.

7. A hot air circulation oven according to claim 1, characterized in that the placing frame (6) comprises a placing frame (61) with an upper opening and a closing plate (62) covering the upper opening of the placing frame (61), wherein the closing plate (62) is detachably connected with the placing frame (61).

8. The hot air circulation oven according to claim 7, wherein the placing frame (61) is provided with an insertion opening (612) at an upper opening, the sealing plate (62) is fixedly provided with an insertion block (621), the insertion block (621) is inserted into the insertion opening (612), one side of the sealing plate (62) away from the insertion block (621) is fixedly provided with an elastic clamping block (622), the placing frame (61) is provided with a clamping groove (613) matched with the elastic clamping block (622), and the elastic clamping block (622) is clamped in the clamping groove (613).

9. The hot air circulation oven according to claim 7, wherein the placing frame (61) and the closing plate (62) are provided with a plurality of air holes (611).

10. A hot air circulating oven according to claim 1, characterized in that a fan (4) is arranged inside the drying box (1), the fan (4) being electrically connected to the control panel (5).