CN215321494U

CN215321494U - Thermal printer and smart machine

Info

Publication number: CN215321494U
Application number: CN202120686006.4U
Authority: CN
Inventors: 胡琳; 周颖; 杨叶平
Original assignee: Zhuhai Howbest Label Printer Co ltd
Current assignee: Zhuhai Howbest Label Printer Co ltd
Priority date: 2021-04-02
Filing date: 2021-04-02
Publication date: 2021-12-28
Anticipated expiration: 2031-04-02

Abstract

The utility model provides a thermal printer and an intelligent device, which comprise a slide lock, a limiting swing rod, an uncovering button and two elastic pieces, wherein the uncovering button is movably arranged on a base along a pressing direction, the inner side of the uncovering button is provided with a limiting block, the limiting swing rod is movably arranged on the inner side of the uncovering button along with the uncovering button, the free end of the limiting swing rod can move along the pressing direction relative to the uncovering button, the first elastic piece is connected with the limiting swing rod, the free end can be adjacent to the limiting block, an insertion gap is formed between the free end and the limiting block, a lock pin of the slide lock can move into the insertion gap along a locking direction, the lock pin can be adjacent to the free end, and the second elastic piece is connected with the slide lock. When uncapping behind the sliding lock unblock, the lockpin removes to inserting in the space, along with the restoration of uncapping the button, the lockpin forms the uncapping of uncapping the button again spacing, realizes then that uncapping locks or the unblock is easy and simple to handle.

Description

Thermal printer and smart machine

Technical Field

The utility model relates to the field of thermal printing, in particular to a thermal printer and intelligent equipment.

Background

Nowadays, more and more commercial places use automatic intelligent equipment, such as intelligent counters of banks, automatic teller machines, ticket dispensers, queuing machines, sales terminals, cash terminals, self-service checkout machines, express delivery points or catering merchants and the like, and the above application fields all adopt thermal printers for printing transaction receipts, labels, tickets or bills. The existing thermal printer is provided with a base, a cover body, a rubber roller, a thermal sensitive sheet and a locking piece, wherein one of the thermal sensitive sheet and the rubber roller is arranged on the base, the other one of the thermal sensitive sheet and the rubber roller is arranged on the cover body, the thermal sensitive sheet and the rubber roller are opposite to each other and form a paper feeding channel, the thermal sensitive sheet abuts against the rubber roller, and the thermal printing paper presents printing pattern content after passing through the thermal sensitive sheet.

When thermal printing paper exhausts, need open the lid, change new thermal printing paper and place the paper feed passageway in, the lid closes the lid again and makes thermal sensitive piece and rubber roll centre gripping beat printing paper, because the mechanism that uncaps generally sets up on one side outwards, is opened by the mistake easily for printer operating stability is not high, even if has set up the locking structure, and nevertheless locking operation is also complicated relatively.

SUMMERY OF THE UTILITY MODEL

A first object of the present invention is to provide a thermal printer in which the operation of opening the cover lock is simple.

A second object of the present invention is to provide a smart device having the above thermal printer.

In order to achieve the first purpose of the utility model, the utility model provides a thermal printer, which comprises a base, a cover body, a rubber roller, a thermal sensitive sheet and a locking piece, wherein the cover body is connected with the base; the cover body is provided with a clamping part, the lock catch part is provided with a lock part, the lock catch part is arranged on the base, and the clamping part and the lock part are detachably clamped; the thermal printer further comprises a sliding lock, a limiting swing rod, an uncovering key, a first elastic piece and a second elastic piece, wherein the base is provided with an installation groove, the uncovering key is movably installed in the installation groove along the pressing direction, the uncovering key is connected with the locking piece and can drive the locking piece to move, an operation part is arranged on the outer side of the uncovering key, and a limiting block is arranged on the inner side of the uncovering key; the limiting swing rod is movably arranged on the inner side of the uncovering key along with the uncovering key, the limiting swing rod is provided with a free end, the free end can move relative to the uncovering key along a pressing direction, the first elastic piece is connected with the limiting swing rod and applies elastic force along the pressing direction to the free end, the free end can be adjacent to the limiting block, and an insertion gap is formed between the free end and the limiting block; the sliding lock is movably arranged on the base along the locking direction, the sliding lock is provided with a lock pin, the lock pin can move into the insertion gap along the locking direction, the lock pin can be abutted to the free end, and the second elastic piece is connected with the sliding lock and applies elastic force along the locking direction to the sliding lock.

According to the scheme, the cover body is stably covered on the base through the clamping of the clamping part and the locking part, the thermosensitive sheet and the rubber roller are opposite to each other and form clamping on printing paper, the locking part of the locking part needs to be driven when the cover body is opened, the locking part is separated from the clamping part, based on the structure, the lock pin of the sliding lock forms limit fit with the limit block, the uncovering movement of the uncovering key in the pressing direction is blocked, the mistaken uncovering prevention is realized, when the uncovering locking is released, the sliding lock is shifted along the locking direction, the lock pin is separated from the limit block and the free end is abutted to the limit block, the free end forms limit on the lock pin, the lock pin cannot form limit on the pressing of the uncovering key, the uncovering key is pressed to drive the locking part to move, the uncovering is realized, the lock pin moves into the insertion gap, and the lock pin forms uncovering limit on the uncovering key again along with the resetting of the uncovering key, therefore, the unlocking or unlocking operation is simple and convenient.

The further scheme is that the limiting swing rod is hinged to the uncovering button, and the free end rotates relative to the uncovering button based on the hinge position of the limiting swing rod.

The further scheme is that an avoiding groove is formed between the hinge position and the free end of the limiting swing rod, a penetrating column is arranged on the inner side of the cover opening key, penetrates through the avoiding groove to be connected with the locking fastener and can drive the locking fastener to move.

It is thus clear that through articulated mode with spacing pendulum rod with the button connection of uncapping and realize along the linkage of the direction of uncapping to through wearing the post and dodging the setting in groove, not only the structure is simpler and compact, and the assembly is simple and convenient, and the free end pivoted moving means is more smooth and easy with the cooperation of stopper or lockpin.

According to a further scheme, the limiting swing rod comprises a transverse rod and two longitudinal rods, the transverse rod is connected between the two longitudinal rods, the free end of the transverse rod is located on the transverse rod, the hinge position of the longitudinal rod is located on the longitudinal rod, the longitudinal rod is hinged to the cover opening key, the transverse rod and the two longitudinal rods are enclosed to form avoiding grooves, and the two longitudinal rods are located on two opposite sides of the penetrating column.

Therefore, the structure of the limiting swing rod is more stable through the combination of the transverse rod and the two longitudinal rods, and the free end can be stably matched with the limiting block or the lock pin.

The thermal printer further comprises a cover opening spring, the cover opening spring is sleeved outside the penetrating column and located in the avoiding groove, and the cover opening spring is connected with the cover opening key and applies elastic force along the pressing direction to the cover opening key.

It is thus clear that, wear the post through uncap spring housing outside to be located and dodge the inslot, its elasticity reset structure arrange more compactly, and for uncap the button provide stable restoring force.

In a further aspect, the first resilient member is a spring, a first end of the spring abuts the free end, and a second end of the spring is coupled to the base.

As can be seen from the above, the free end can be provided with a stable elastic force in the pressing direction by the abutment of the spring with the free end.

It is further preferred that the pressing direction is perpendicular to the locking direction.

The lock pin is provided with a first limiting surface at the outward side in the pressing direction, a second limiting surface at the inward side in the pressing direction, the lock pin can be positioned between the limiting block and the free end, the first limiting surface is adjacent to the limiting block, and the second limiting surface is adjacent to the free end.

In a further aspect, a third limiting surface is disposed at an end of the lock pin in the locking direction, and the third limiting surface may abut the free end or the limiting block.

It is from top to bottom visible, through making the spacing face of third of lockpin adjoin with free end or stopper along the locking direction to cooperate first spacing face and the spacing face of second respectively with the adjacency of stopper and free end, realize corresponding locking and unlocking state then, thereby realize unblock, uncap the back automatic re-setting become the locking state, thereby improve the locking stability of lid, avoid the mistake to uncap.

In order to achieve the second object of the utility model, the utility model provides an intelligent device, which comprises the thermal printer according to the scheme.

Drawings

FIG. 1 is a block diagram of an embodiment of a thermal printer according to the present invention.

Fig. 2 is a structural view of the thermal printer according to the embodiment of the present invention after the cover is opened.

Fig. 3 is an exploded view of an embodiment of the thermal printer of the present invention.

FIG. 4 is a block diagram of a cover and slide lock in an embodiment of a thermal printer according to the utility model.

Fig. 5 is an exploded view of a lid release button and base in an embodiment of the thermal printer of the present invention.

FIG. 6 is a cross-sectional view of an embodiment of a thermal printer of the present invention in a locked state.

Fig. 7 is a sectional view of an embodiment of the thermal printer of the present invention in an unlocked state.

Fig. 8 is a sectional view of an embodiment of a thermal printer according to the present invention in an uncapped state.

Fig. 9 is a sectional view of an embodiment of a thermal printer according to the present invention in a state where a lock pin is inserted.

FIG. 10 is a block diagram of an embodiment of a thermal printer according to the present invention from an inboard perspective

Fig. 11 is a schematic view of the engagement of the catch member and the rubber roller in an embodiment of the thermal printer of the present invention.

Fig. 12 is an exploded view of a cover in an embodiment of a thermal printer according to the utility model.

Fig. 13 is a cross-sectional view along a paper path in an embodiment of a thermal printer according to the present invention.

Fig. 14 is a structural view of another embodiment of the thermal printer of the present invention.

FIG. 15 is a block diagram of another embodiment of a thermal printer according to the present invention from another perspective.

The utility model is further explained with reference to the drawings and the embodiments.

Detailed Description

Referring to fig. 1 to 13, the thermal printer 1 includes a base 2, a cover 3, a rubber roller 12 and a thermal sheet 11, the cover 3 is hinged to the base 2, a paper bin 201 is disposed in the base 2, a paper outlet 112 is formed between the cover 3 and the base 2, the thermal sheet 11 is disposed on the base 2, the rubber roller 12 is rotatably disposed on the cover 3, the thermal sheet 11 and the rubber roller 12 are opposite to each other and form a paper feeding channel 111, the cover 3 covers the paper bin 201, and the paper feeding channel 111 is communicated between the paper outlet 112 and the paper bin 201.

The thermal printer 1 further comprises a locking piece 16, a first transmission piece 14, a second transmission piece 15, a rotating shaft 18 and two springs 17, wherein the locking piece 16 comprises a connecting plate 161 located in the middle and locking arms 162 located at two ends of the connecting plate 161, a locking portion 163 is arranged at a free end of each locking arm 162, each locking portion 163 is arranged in a locking groove, a clamping portion 121 is arranged on the cover body 3, the clamping portion 121 is located on the end portion of the rubber roll 12 and is arranged in a cylinder, and a transmission gear is arranged at one end portion of the rubber roll 12. One end of the two springs 17 is connected to the base 2, the other end of the two springs 17 is connected to the connecting plate 161, the rotating shaft 18 passes through the two locking arms 162 and is connected to the base 2, and then the locking member 16 is rotatably disposed on the base 2. The first transmission piece 14 is hinged to the base 2, the first end 141 of the first transmission piece 14 is connected to the through post 224, the second end 142 of the first transmission piece 14 is adjacent to the transmission post 151 of the second transmission piece 15, the transmission post 151 of the second transmission piece 15 further passes through the locking arm 162 to one side and can drive the locking arm 162 to rotate around the rotating shaft 18, and the second transmission piece 15 is connected to the rotating shaft 18 through the through hole 15.

The base 2 is provided with a mounting groove 21 at a position close to the paper outlet 112 and the first transmission member 14, the mounting groove 21 is provided with an opening outward, a through hole 211 is provided through the bottom wall of the mounting groove 21, and a bayonet 213 is provided on the side wall of the mounting groove 21.

The thermal printer 1 further includes a slide latch 24, a limit swing lever 23, a door opening button 22, a first elastic member 235, a second elastic member 256, and a door opening spring 225, and the door opening button 22 is movably installed in the installation groove 21 in the pressing direction Z.

The outside of uncap button 22 is provided with operating part 221, operating part 221 is the plane setting, the interior terminal surface 222 of uncap button 22 in the inboard is provided with stopper 223 and two connecting blocks, stopper 223 is connected between two connecting blocks, the tip of connecting block is provided with buckle 226, the connecting block still is provided with the hinge 227 relatively, the interior terminal surface 222 of uncap button 22 still is provided with the post 224 inwards, it follows to wear the post 224, it is located between two connecting blocks to wear the post 224, uncap spring 225 overlaps outside the post 224.

The limit swing link 23 includes a hinge 234, a cross bar and two longitudinal bars 232, the cross bar is connected between the two longitudinal bars 232, the hinge 234 and the cross bar are located at opposite sides, the hinge 234, the cross bar and the two longitudinal bars 232 enclose an avoidance groove 233, an end of the hinge 234 forms a hinge end and is inserted into the hinge hole 227, thereby realizing the hinge of the limit swing link 23 on the door opening button 22, the limit swing link 23 is movably installed at an inner side of the door opening button 22 along with the door opening button 22, the limit swing link 23 is provided with a free end 231, the free end 231 is located on the cross bar, the hinge position is located on the longitudinal bar 232, thereby the free end 231 rotates relative to the door opening button 22 based on the hinge 234, and the free end 231 can move relative to the door opening button 22 along the pressing direction Z, the penetrating post 224 passes through the avoidance groove 233 and the penetrating hole 211 and abuts the first end 141 of the first transmission member 14, thereby realizing the connection with the locking member 16 and driving the movement of the locking member 16, and the two vertical rods 232 are located at two opposite sides of the through column 224, and can realize the separation or engagement of the clamping part 121 and the locking part 163.

The buckle 226 of the open-cover button 22 is engaged with the bayonet 213, the open-cover spring 225 is located in the escape groove 233, the open-cover spring 225 elastically abuts between the open-cover button 22 and the base 2, and the open-cover spring 225 applies an elastic force along the pressing direction Z to the open-cover button 22.

The first elastic member 235 is a spring, the bottom wall of the mounting groove 21 is provided with a positioning column 212, the spring is sleeved outside the positioning column 212, a first end of the spring is abutted against the free end 231, a second end of the spring is connected with the base 2, and the first elastic member 235 applies an elastic force outwards along the pressing direction Z to the free end 231.

The thermal printer 1 further comprises a cover 25, a secondary knife 34 and a main knife device 33, wherein the cover 25 is detachably mounted on the base 2, the cover 25 is positioned on one side of the cover opening key 22 based on the locking direction X, the cover 25 is provided with a plurality of buckles 253, the inner side of the cover 25 is provided with a mounting groove 252, the cover 25 is provided with an outward outer end surface, an operation opening 251 is arranged on the outer end surface in a penetrating way, a mounting block 255 is arranged in the mounting groove 252, a sliding groove is formed in the mounting block 255, a sliding lock 24 can be arranged in the sliding groove along the locking direction X and positioned between the mounting block 255 and the cover 25, the mounting block 255 is further provided with a limiting block 2551, the sliding lock 24 is provided with a limiting groove 243, the limiting groove 243 is in limiting fit with the limiting block 2551, the sliding lock 24 can be arranged on the base 2 in a movable way along the locking direction X, an opening 253 is arranged on the side wall of the cover 25 close to the cover opening key 22 in a penetrating way, the sliding lock 24 is provided with a lock pin 245, the lock pin 245 movably passes through the opening 253 and protrudes into the mounting groove 21, and the pressing direction Z is perpendicular to the locking direction X. The second elastic member 256 is a spring, the second elastic member 256 is disposed in the slide groove of the mounting block 255, and the second elastic member 256 is connected to the slide latch 24 and applies an elastic force in the locking direction X to the slide latch 24. The slide latch 24 is provided with an operation portion 241 on the outside, and the operation portion 241 is located in the operation opening 251 and is slidable in the operation opening 251.

Referring to fig. 6, fig. 6 is a cross-sectional view of the thermal printer in a locked state, the lock pin 245 is provided with a first limiting surface on the outward side in the pressing direction Z, the lock pin 245 is provided with a second limiting surface on the inward side in the pressing direction Z, the lock pin 245 is located between the limiting block 223 and the free end 231 in the pressing direction Z, the first limiting surface is adjacent to the limiting block 223, the second limiting surface is adjacent to the free end 231, and then the cover opening key 22 is limited by the lock pin 245 and cannot move inward in the pressing direction Z, so that locking is achieved.

Referring to fig. 7, fig. 7 is a cross-sectional view of the thermal printer in an unlocked state, when unlocking, the operating portion 241 may be moved along the locking direction X away from the cover opening button 22, so as to separate the lock pin 245 from the stopper 223, and under the elastic force of the first elastic member 235, the free end 231 may be abutted to the stopper 223, and the end of the lock pin 245 in the locking direction X is provided with a third stopper surface, which may be abutted to the free end 231, so as to block the locking movement of the lock pin 245, and then the cover opening button 22 may move inward along the pressing direction Z.

Referring to fig. 8, with reference to fig. 10 and 11, fig. 8 is a cross-sectional view of the thermal printer in the uncapping state, as the operating portion 221 is pressed to move the uncapping key 22 inward along the pressing direction Z, then the penetrating column 224 pushes the first end 141 of the first transmission member 14 to rotate, as the first transmission member 14 drives the second transmission member 15 to rotate, then the transmission column 151 also drives the lock portion 163 of the lock arm 162 to move, so that the card portion 121 is separated from the lock portion 163, and the cover 3 can be opened smoothly.

Referring to fig. 9, fig. 9 is a cross-sectional view of the thermal printer in a latch insertion state, during a cover opening pressing operation, since the free end 231 may abut against the stopper 223, and then an insertion gap is formed between the free end 231 and the stopper 223, the latch 245 may move into the insertion gap along the locking direction X under the action of the second elastic member 256, and then the third stopper surface of the latch 245 abuts against the stopper 223, and the free end 231 abuts against the latch 245 and is located inward in the pressing direction Z of the latch 245.

As the external force is removed from the operation portion 221, the lid opening button 22 is sprung outward by the elastic force of the lid opening spring 225, and then returns to the state shown in fig. 6, and the automatic return to the locked state is realized.

Referring to fig. 12 and 13, and in combination with fig. 10, the secondary blade 34 and the main blade unit 33 are respectively disposed on two opposite sides of the paper output port 112, the secondary blade 34 is connected to the base 2, the cover 25 is provided with an entry edge 257, the entry edge 257 faces the main blade, the base 2 is provided with a plurality of slots 203 on the periphery of the secondary blade 34, and the snaps 253 are detachably engaged with the slots 203, thereby realizing that the cover 25 is disposed outside the secondary blade 34 and detachably connected with the base 2.

The cover body 3 comprises a bottom cover 32 and a face cover 31, the bottom cover 32 and the face cover 31 enclose a containing cavity, a main knife device 33 is arranged in the containing cavity, the main knife device 33 is fixedly connected with the bottom cover 32, the main knife device 33 comprises a main knife 331 and a driving device, the driving device is connected with the main knife 331 and drives the main knife to move towards or away from the auxiliary knife 34, the specific driving mode of the main knife device 33 can refer to the technical scheme of the cutter disclosed in CN212422577U, and under the driving of the driving device, the main knife 331 can extend into the knife edge 257 and can be matched with the auxiliary knife 34 to cut off printing paper.

The cover 3 is provided with hinge arms 35 on both sides, the hinge arms 35 are provided with a first hinge portion 352 and a blocking convex portion 351 located on the radial periphery of the first hinge portion 352, the base 2 is provided with a hinge groove 202, the hinge groove 202 is provided with a second hinge portion and at least two positioning

concave portions

203 and 204, the positioning concave portion 204 is composed of a groove wall and a blocking wall of the hinge groove 202, the two positioning

concave portions

203 and 204 are located on the radial periphery of the second hinge portion, the hinge arms 35 are rotatably arranged in the hinge groove 202, the first hinge portion 352 is hinged with the second hinge portion 352, and a torsion spring 36 is further provided to connect between the hinge arms 35 and the hinge groove 202, the blocking convex portion 351 is detachably blocked with the positioning

concave portions

203 or 204, thereby realizing two-section opening of the cover 3, and the main knife device 33 also moves along with the cover 3 along with the opening of the cover 3.

The base 2 is provided with a paper blocking roller 133 in the paper bin 201, the paper blocking roller 133 is close to the hinged position of the base 2 and the cover body 3, the paper bin 201 is provided with chutes 131 on two opposite side walls respectively, the paper blocking roller 133 is arranged between the two chutes 131, the thermal printer 1 further comprises two paper blocking elastic pieces 132, the paper blocking elastic pieces 132 adopt springs, and the paper blocking elastic pieces 132 are connected with the end part of the paper blocking roller 133, so that the paper blocking roller 133 can elastically move in the chutes 131.

When the cutter is clamped, the main cutter 331 extends into the knife inlet 257 at the moment, the bottom cover 32 is conveniently detached, then the main cutter device 33 moves outwards along with the opening of the cover body 3 through the cover opening action, then the printer can reset, the separated main cutter can smoothly retract, and then the cutter clamping problem is simply solved.

Referring to fig. 14 and 15, the thermal printer can also be used as a desktop printer by adding an outer enclosure 4, and can be used as an embedded printer when the outer enclosure is not added, the outer enclosure 4 is arranged in a cube, the outer enclosure 4 is provided with a mounting cavity, the mounting cavity is provided with a square mounting port, the base 2 is mounted in the mounting cavity and connected with the outer enclosure 4, the outer enclosure 4 is provided with a bottom surface 41 on the side opposite to the paper outlet 112, the outer enclosure 4 is provided with a side surface 42 on the side adjacent to the bottom surface 41, the bottom surface 41 and the side surface 42 are respectively provided with a plurality of

foot pads

411 and 421, and the square outer enclosure 4 enables the thermal printer to be placed in a plurality of ways to adapt to different use places.

The intelligent equipment comprises a shell, wherein the shell of the intelligent equipment is provided with an embedded thermal printer or a desktop thermal printer according to the scheme, and the intelligent equipment comprises an intelligent counter of a bank, an automatic teller machine, a ticket machine, a number machine, a sales terminal, a cash register terminal, a self-service checkout machine or a self-service vending machine and the like.

The above embodiment is only a preferred embodiment of the present application, and when in actual need, more changes can be made, such as position changes of the rubber roller and the heat sensitive sheet, that is, the heat sensitive sheet is arranged on the cover body, the rubber roller and the cover body are additionally provided with the clamping part which can also realize detachable connection with the base, the cover opening spring can be not adopted, the cover opening key can also be reset by utilizing the elastic force of the first spring 225 or the reset force of the spring 17 of the locking piece, and the limit swing rod 23 can realize elastic movement of the free end along the pressing direction by adopting a sliding and sliding way in addition to a hinged way.

Based on the structure, the lock pin of the sliding lock forms limit fit with the limit block to block the uncovering movement of the uncovering key in the pressing direction so as to realize false uncovering prevention, when the uncovering locking is released, the sliding lock is shifted along the locking direction to separate the lock pin from the limit block and the free end abuts against the limit block, the free end forms limit on the lock pin, the lock pin cannot form limit on the pressing of the uncovering key, then the uncovering key is pressed to drive the lock catch to move, and uncovering is realized, the lock pin moves into the insertion gap, and along with the resetting of the uncovering key, the lock pin forms uncovering limit on the uncovering key again, therefore, the unlocking or unlocking operation is simple and convenient.

And, through setting the main sword device on the lid, when taking place the card sword, main sword promptly, beat printing paper and the mutual centre gripping of vice sword, because the main sword stretches into to going into in the sword mouth this moment, then through the detachable closing cap to the lid is opened in the utilization, makes main sword device rotate thereupon with the lid and opens, realizes then that main sword and vice sword after separating, and the printer chance resets, and the main sword of separation will retract smoothly, realizes simply solving the card sword problem then.

Claims

1. The thermal printer comprises a base, a cover body, a rubber roller, a thermal sensitive sheet and a locking piece, wherein the cover body is connected to the base, a paper outlet is formed between the cover body and the base, one of the thermal sensitive sheet and the rubber roller is arranged on the base, the other of the thermal sensitive sheet and the rubber roller is arranged on the cover body, the thermal sensitive sheet and the rubber roller are opposite to each other and form a paper feeding channel, and the paper feeding channel is communicated with the paper outlet;

the cover body is provided with a clamping part, the lock catch part is provided with a lock part, the lock catch part is arranged on the base, and the clamping part is detachably clamped with the lock part;

the method is characterized in that:

the thermal printer further comprises a sliding lock, a limiting swing rod, an uncovering key, a first elastic piece and a second elastic piece, wherein the base is provided with an installation groove, the uncovering key is movably installed in the installation groove along a pressing direction, the uncovering key is connected with the lock catch piece and can drive the lock catch piece to move, an operation part is arranged on the outer side of the uncovering key, and a limiting block is arranged on the inner side of the uncovering key;

the limiting swing rod is movably mounted on the inner side of the uncovering key along with the uncovering key, the limiting swing rod is provided with a free end, the free end can move along the pressing direction relative to the uncovering key, the first elastic piece is connected with the limiting swing rod and applies elastic force along the pressing direction to the free end, the free end can be adjacent to the limiting block, and an insertion gap is formed between the free end and the limiting block;

the slide lock is movably provided on the base in a locking direction, the slide lock is provided with a lock pin which is movable into the insertion space in the locking direction, the lock pin is abuttable to the free end, and the second elastic member is connected to the slide lock and applies an elastic force in the locking direction to the slide lock.

2. The thermal printer according to claim 1, wherein:

the limiting swing rod is hinged to the uncovering button, and the free end rotates relative to the uncovering button on the basis of the hinge position of the limiting swing rod.

3. The thermal printer according to claim 2, wherein:

the limiting swing rod is arranged between the hinge position and the free end, an avoiding groove is formed in the inner side of the cover opening key, and a penetrating column is arranged on the inner side of the cover opening key and penetrates through the avoiding groove and the lock catch piece to be connected and drive the lock catch piece to move.

4. The thermal printer according to claim 3, wherein:

the limiting swing rod comprises a cross rod and two longitudinal rods, the cross rod is connected between the two longitudinal rods, the free end is located on the cross rod, the hinge position is located on the longitudinal rods, the longitudinal rods are hinged to the cover opening key, the cross rod and the two longitudinal rods surround the avoiding groove, and the two longitudinal rods are located on two opposite sides of the penetrating column.

5. The thermal printer according to claim 3, wherein:

6. The thermal printer according to claim 1, wherein:

the first elastic piece is a spring, a first end of the spring is abutted to the free end, and a second end of the spring is connected with the base.

7. The thermal printer according to claim 1, wherein:

the pressing direction is perpendicular to the locking direction.

8. The thermal printer according to any one of claims 1 to 7, wherein:

the lock pin is provided with a first limiting surface at the outward side of the pressing direction, a second limiting surface at the inward side of the pressing direction, the lock pin can be positioned between the limiting block and the free end, the first limiting surface is adjacent to the limiting block, and the second limiting surface is adjacent to the free end.

9. The thermal printer according to any one of claims 1 to 7, wherein:

the end part of the lock pin in the locking direction is provided with a third limiting surface, and the third limiting surface can be adjacent to the free end or the limiting block.

10. Smart device, characterized in that it comprises a thermal printer according to any one of the preceding claims 1 to 9.