CN220639259U - Printer head positioner - Google Patents

Abstract

The utility model relates to a printer head positioning device, which comprises a printer head body, wherein the printer head body comprises a main frame and a lifting frame, the main frame is fixedly arranged on a base, the lifting frame is connected with the main frame through a lifting driving device, the lifting driving device is used for driving the lifting frame to move up and down, a bottom mounting frame is arranged at the bottom of the lifting frame and is used for mounting a printing module, a lifting device is arranged between the lifting frame and the bottom mounting frame, the bottom mounting frame is movably connected with the lifting frame through the lifting device, a paper feeding mechanism is arranged on the base, a positioning unit is arranged on the paper feeding mechanism and is positioned at the side of a printing medium, and the positioning unit is used for positioning and limiting the height of the bottom mounting frame from the printing medium. The utility model has the advantages of accurate positioning, no need of manual debugging during secondary positioning, cost saving, printing efficiency improvement and customer satisfaction improvement.

Description

Printer head positioner

Technical Field

The utility model relates to the technical field of ink-jet printing equipment, in particular to a printer head positioning device.

Background

In the printing process of the ink-jet printer, the requirement on the printing precision of the spray head is very high, and in order to ensure the printing precision, the measures adopted generally are as follows: splicing among a plurality of spray heads, mechanically adjusting included angles among the spray heads, mechanically adjusting parallelism between the bottom plate of each spray head and a printing medium, adjusting software and the like. When installing more shower nozzles in the print dolly, because the shower nozzle total mass is heavier, the shower nozzle bottom plate size is great, no matter be assembly process, machining error or dead weight reason, all probably lead to the position slope of shower nozzle bottom plate, still need carry out position adjustment to the shower nozzle this moment to guarantee that the drop point position of shower nozzle injection point is accurate, and the angle of each shower nozzle of individual adjustment is very consuming time and power, and the uniformity hardly guarantees, then wholly carries out position adjustment to the shower nozzle bottom plate on the basis of the shower nozzle installation accuracy on the bottom plate that needs to guarantee.

In order to solve the foregoing problems, chinese patent CN218343081U discloses an inkjet printer, which comprises a printing device, the printing device comprises a main frame, a lifting driving device, a nozzle mounting device, a bottom plate position adjusting device and an ink supply device, the main frame is mounted on a feeding device, the lifting driving device is respectively connected with the main frame and the lifting frame, the nozzle mounting device is arranged at the bottom of the lifting frame, and a nozzle is mounted on the nozzle mounting device. The foregoing prior art has realized the adjustment to the whole front and back position, the beat angle of shower nozzle bottom plate through having set up shower nozzle installation device, however, the aforesaid prior art's inkjet printer is in the use, because the difference of print medium always needs to go up and down to make be in suitable distance between shower nozzle and the print medium, or when the shower nozzle need maintain the washing, also often need to adjust the height of lift frame in order to mutually support with shower nozzle maintenance device, when going up and down to the lift frame whole, because the transmission error of lift drive arrangement, easily lead to the lift frame whole to produce tiny skew, all shower nozzles in the lift frame whole have produced tiny skew promptly, thereby lead to the printing quality to be influenced, and time and human cost of follow-up debugging correction have been increased. In addition, in the transportation process of the machine, the lifting frame is heavy, and the lifting frame is integrally shifted due to jolt and transportation in the road, so that the debugging and correction cost of after-sales technicians is increased, and the satisfaction degree of customers is reduced.

Disclosure of Invention

The utility model aims to provide a printer head positioning device which solves the defects in the prior art, and the technical problems to be solved by the utility model are realized by the following technical scheme.

The utility model provides a printer head positioner, includes the printer head body, the printer head body includes main frame and lifts the frame, main frame fixed mounting is on the base, lift the frame with connect through lifting drive device between the main frame, lifting drive device is used for the drive lift the frame reciprocates, the bottom of lifting the frame is equipped with end installing frame, end installing frame is used for installing the printing module, lift the frame with be equipped with hoist device between the end installing frame, end installing frame passes through hoist device with lift frame swing joint, be equipped with paper feed mechanism on the base, the side position that is located print medium on the paper feed mechanism is equipped with positioning unit, positioning unit is used for right end installing frame is located and is spacing apart from print medium's height.

Preferably, the lifting device comprises a lifting block, a lifting nail and a spring, wherein the lifting block is respectively arranged on the inner side surfaces of the inner left side plate and the inner right side plate of the lifting frame, the lower end part of the lifting nail is fixedly connected with the bottom mounting frame, the upper end of the lifting nail is arranged in the lifting block in a penetrating manner and can move up and down relative to the lifting block, and the spring is sleeved outside the lifting nail and is positioned between the lifting block and the bottom mounting frame.

Preferably, the hanging block is provided with a stepped hole, the upper end of the hanging nail is provided with a limit head, the lower end of the hanging nail is provided with a threaded part, the hanging nail is arranged in the stepped hole in a penetrating mode, the limit head is arranged in a large hole at the upper end of the stepped hole, and the hanging nail is fixedly connected with the bottom mounting frame through the threaded part.

Preferably, grooves are respectively formed in the left side and the right side of the bottom mounting frame, the grooves are used for accommodating the lower end portions of the springs, mounting holes are formed in the center positions of the grooves, and the lower end portions of the hanging nails are mounted in the mounting holes.

Preferably, the positioning unit comprises a positioning block I and a positioning block II, wherein the positioning block I is respectively provided with a positioning pin and a positioning nail, the positioning pins are used for positioning and limiting the position of the bottom mounting frame, and the positioning nails are used for limiting the lowest position of the bottom mounting frame, which is away from the printing medium.

Preferably, the number of the positioning blocks I and the number of the positioning blocks II are two, wherein the two positioning blocks I are respectively arranged on the left front side and the right rear side of the paper feeding mechanism, and the two positioning blocks II are respectively arranged on the left rear side and the right front side of the paper feeding mechanism.

Preferably, a positioning pin hole matched with the positioning pin is formed in the bottom of the bottom mounting frame, and the positioning pin hole is used for accommodating the positioning pin.

Preferably, the paper feeding mechanism comprises supporting wallboards which are arranged at intervals front and back, and the positioning block I and the positioning block II are arranged on the inner side surfaces of the supporting wallboards.

Preferably, the lifting driving device comprises a motor fixedly mounted on the main frame, a screw rod is arranged at the output end of the motor, a screw nut is sleeved on the screw rod, and the screw nut is fixedly connected with the lifting frame.

Preferably, the motor is mounted on a motor mounting plate, the motor mounting plate is fixedly mounted on the main frame, the nut is mounted on a nut seat, and the nut seat is fixedly mounted on the lifting frame.

In the utility model, the printer head body is arranged above the base, the main frame is fixedly connected with the base, the lifting frame is nested in the main frame, a plurality of printing modules are arranged on the bottom mounting frame, the bottom of each printing module is provided with a spray head, a printing medium is arranged below the spray head on the base, and ink drops are sprayed on the printing medium through the spray heads to realize printing of patterns. When the height of the spray head is adjusted, the lifting frame is driven to move upwards through the lifting driving device, the lifting frame drives the bottom mounting frame to move upwards through the lifting device, so that the height of the spray head is lifted, the spray head is required to be lowered to a proper distance from a printing medium during printing, at the moment, the lifting driving device drives the lifting frame to move downwards, the lifting device drives the bottom mounting frame to move downwards to a target height, and the positioning unit positions and limits the height of the bottom mounting frame, so that the spray head is at a proper distance from the printing medium.

Compared with the prior art, the positioning and limiting of the lifting frame to the bottom mounting frame are changed from rigidity to flexibility, the positioning and limiting of the bottom mounting frame mainly depend on the positioning unit arranged on the base, and the positioning unit is arranged on the side of a printing medium and is unchanged relative to the position of the printing medium, so that when the lifting frame is lifted to adjust the height of the spray head, compared with the mechanical structure relation positioning between the bottom mounting frame and the lifting frame and the height positioning of the bottom mounting frame by the lifting driving device in the prior art, the positioning and limiting of the positioning unit in the embodiment are more accurate and stable, have no assembly error and transmission error, and do not need manual debugging; the positioning unit is arranged at the side of the printing medium on the paper feeding mechanism, and the position of the positioning unit is not changed in the transportation process, so that after the transportation is finished, the bottom mounting frame can be accurately positioned through the positioning unit, the time cost and the labor cost for debugging and correcting which are increased due to inaccurate positioning of the spray head are saved, the delay of the printing production process is avoided, and the customer satisfaction is improved.

Drawings

FIG. 1 is a schematic diagram of the structure of the present utility model;

FIG. 2 is a schematic view of the printer head body according to the present utility model;

FIG. 3 is a schematic diagram of a positioning unit according to the present utility model;

FIG. 4 is a schematic structural view of a hoisting device according to the present utility model;

FIG. 5 is a schematic view of an assembled structure of a main frame and a lifting frame according to the present utility model;

FIG. 6 is a schematic view of a lifting driving device according to the present utility model;

FIG. 7 is a schematic view of a side support plate according to the present utility model;

FIG. 8 is a schematic view of another angle of the side support plate of the present utility model;

FIG. 9 is a schematic cross-sectional view of a hanging block according to the present utility model;

FIG. 10 is a schematic view of a staple according to the present utility model;

the reference numerals in the drawings are in turn: 1. base, 11, paper feeding mechanism, 111, support wallboard, 12, supporting seat, 131, positioning block I,132, positioning block II,133, positioning pin, 134, positioning pin, 2, printer head body, 21, main frame, 211, main back plate, 212, outer left side plate, 213, outer right side plate, 22, lifting frame, 221, inner back plate, 222, inner left side plate, 223, inner right side plate, 23, bottom mounting frame, 231, side support plate, 2311, mounting hole, 2312, groove, 2313, positioning pin hole, 232, cross support plate, 24, lifting device, 241, lifting block, 2411, stepped hole, 242, lifting pin, 2421, positioning head, 2422, screw portion, 243, spring, 25, printing module, 261, motor, 262, screw rod, 263, screw seat, 264, motor mounting plate, 265, screw, 27, mounting seat.

Detailed Description

It should be noted that, in the case of no conflict, the embodiments and features in the embodiments may be combined with each other. The utility model will be described in detail below with reference to the drawings in connection with embodiments.

Example 1:

in a printer head positioning device, the improvement comprising: including printer head body 2, printer head body 2 includes main frame 21 and lifts frame 22, main frame 21 fixed mounting is on base 1, lift frame 22 with be connected through lift drive between the main frame 21, lift drive is used for the drive lift frame 22 reciprocates, the bottom of lifting frame 22 is equipped with bottom mounting frame 23, bottom mounting frame 23 is used for installing printing module 25, lift frame 22 with be equipped with hoist device 24 between the bottom mounting frame 23, bottom mounting frame 23 passes through hoist device 24 with lift frame 22 swing joint, be equipped with paper feed mechanism 11 on the base 1, be equipped with the positioning unit in the lateral position of print medium on the paper feed mechanism 11, the positioning unit is used for right bottom mounting frame 23 is apart from the high location and the spacing of print medium.

In this embodiment, referring to fig. 1 to 4, the printer head body 2 is disposed above the base 1, the main frame 21 is fixedly connected with the base 1, the lifting frame 22 is nested in the main frame 21, the bottom mounting frame 23 is provided with a plurality of printing modules 25, the bottom of the printing modules 25 is provided with a nozzle, a printing medium is disposed below the nozzle on the base 1, and ink droplets are ejected onto the printing medium by the nozzle to realize printing of a pattern. When the height of the spray head is adjusted, the lifting frame 22 is driven to move upwards through the lifting driving device, the lifting frame 22 drives the bottom mounting frame 23 to move upwards through the lifting device 24, so that the height of the spray head is lifted, the spray head needs to be lowered to a proper distance from a printing medium during printing, at the moment, the lifting driving device drives the lifting frame 22 to move downwards, the lifting device 24 drives the bottom mounting frame 23 to move downwards to a target height, and the positioning unit positions and limits the height of the bottom mounting frame 23, so that the spray head is at a proper distance from the printing medium.

Compared with the prior art, the positioning and limiting of the bottom mounting frame 23 by the lifting frame 22 is changed from rigidity to flexibility, the positioning and limiting of the bottom mounting frame 23 mainly depend on the positioning unit arranged on the base 1, and the positioning unit is arranged at the side of a printing medium and is unchanged relative to the position of the printing medium, so that when the lifting frame is lifted to adjust the height of the spray head, compared with the mechanical structure relation positioning between the bottom mounting frame 23 and the lifting frame 22 and the height positioning of the bottom mounting frame by the lifting driving device in the prior art, the positioning and limiting of the positioning unit in the embodiment are more accurate and stable, have no assembly error and transmission error, and do not need manual debugging; the positioning unit is arranged at the side of the printing medium on the paper feeding mechanism 11, and the position of the positioning unit is not changed in the transportation process, so that after the transportation is finished, the bottom mounting frame 23 can be accurately positioned by the positioning unit, the time cost and the labor cost for debugging and correcting which are increased due to inaccurate positioning of the spray head are saved, the delay of the printing production process is avoided, and the customer satisfaction is improved.

Further, the left and right sides of the main frame 21 are respectively provided with a mounting seat 27, the base 1 is provided with a supporting seat 12 matched with the mounting seat 27, and the mounting seat 27 and the supporting seat 12 are connected with each other to realize the fixed connection of the main frame 21 and the base 1.

Further, referring to fig. 5 and 6, the lifting driving device includes a motor 261 fixedly installed on the main frame 21, a screw rod 262 is provided at an output end of the motor 261, a screw nut 265 is sleeved on the screw rod 262, and the screw nut 265 is fixedly connected with the lifting frame 22.

Further, the motor 261 is mounted on a motor mounting plate 264, the motor mounting plate 264 is fixedly mounted on the main frame 21, the screw 265 is mounted on a screw seat 263, and the screw seat 263 is fixedly mounted on the lifting frame 22.

In this embodiment, when the lifting driving device works, the motor 261 rotates to drive the screw rod 262 to rotate, so as to drive the screw 265 to move up and down, and further drive the lifting frame 22 to move up and down.

Further, the main frame 21 includes a main back plate 211, an outer left side plate 212 and an outer right side plate 213 are respectively disposed on the left and right sides of the main back plate 211, and the motor 261 is mounted on the main back plate 211 through a motor mounting plate 264.

Further, the lifting frame 22 includes an inner back plate 221, an inner left side plate 222 and an inner right side plate 223 are respectively disposed on the left side and the right side of the inner back plate 221, and the screw 265 is mounted on the inner back plate 221 through a screw seat 263.

Example 2:

on the basis of embodiment 1, referring to fig. 4, the lifting device 24 includes a lifting block 241, a lifting nail 242 and a spring 243, wherein the lifting block 241 is respectively mounted on the inner side surfaces of the inner left side plate 222 and the inner right side plate 223 of the lifting frame 22, the lower end portion of the lifting nail 242 is fixedly connected with the bottom mounting frame 23, the upper end of the lifting nail 242 is inserted into the lifting block 241 and can move up and down relative to the lifting block 241, and the spring 243 is sleeved outside the lifting nail 242 and is located between the lifting block 241 and the bottom mounting frame 23.

Further, referring to fig. 9 and 10, a stepped hole 2411 is formed in the hanging block 241, a limiting head 2421 is formed at an upper end of the hanging nail 242, a threaded portion 2422 is formed at a lower end of the hanging nail 242, the limiting head 2421 is placed in a large hole at an upper end of the stepped hole 2411 after the hanging nail 242 is inserted into the stepped hole 2411, and the hanging nail 242 is fixedly connected with the bottom mounting frame 23 through the threaded portion 2422.

Further, the hoisting devices 24 are respectively disposed at front and rear ends of the inner side surfaces of the inner left side plate 222 and the inner right side plate 223.

Further, referring to fig. 7, grooves 2312 are formed on both sides of the bottom mounting frame 23, the grooves 2312 are used for accommodating the lower ends of the springs 243, a mounting hole 2311 is formed in the center of the grooves 2312, and the lower ends of the hanging nails 242 are mounted in the mounting hole 2311.

Further, referring to fig. 3, the positioning unit includes a positioning block I131 and a positioning block II132, where the positioning block I131 is provided with a positioning pin 133 and a positioning pin 134, the positioning pin 133 is used to position and limit the position of the bottom mounting frame 23, and the positioning pin 134 is used to limit the lowest position of the bottom mounting frame 23 from the printing medium.

Further, the number of the positioning blocks I131 and the number of the positioning blocks II132 are two, wherein the two positioning blocks I131 are respectively mounted on the left front side and the right rear side of the paper feeding mechanism 11, and the two positioning blocks II132 are respectively mounted on the left rear side and the right front side of the paper feeding mechanism 11.

Further, referring to fig. 8, a positioning pin hole 2313 matching with the positioning pin 133 is provided at the bottom of the bottom mounting frame 23, and the positioning pin hole 2313 is used for accommodating the positioning pin 133.

In this embodiment, during printing, the bottom mounting frame 23 is located at the target height of the bottom mounting frame 23 during printing, at this time, the hanging blocks 241 of the hanging device 24 located above the four corners of the bottom mounting frame 23 press the springs 243 to press the bottom mounting frame 23 on the positioning unit, the spacing heads 2421 at the upper ends of the hanging nails 242 are in a separated state with the hanging blocks 241, and the positioning pins 133 of the positioning unit are placed in the positioning pin holes 2313 at the bottom of the bottom mounting frame 23 to position and limit the bottom mounting frame 23, so as to avoid movement in the horizontal direction, and the upper surfaces of the positioning nails 134 are in contact with the bottom surface of the bottom mounting frame 23 to limit the height of the bottom mounting frame 23, so as to ensure that the bottom mounting frame 23 is at a proper height, i.e. ensure that a proper distance is kept between the nozzle and the printing medium. When the lifting driving device drives the lifting frame 22 to ascend, firstly the lifting block 241 is abutted against the limiting head 2421 of the lifting nail 242, and in the process of continuing to ascend the lifting frame 22, the lifting block 241 drives the lifting nail 242 to ascend, so that the bottom mounting frame 23 is driven to ascend, and then the positioning pin 133 is separated from the positioning pin hole 2313; when the lifting driving device drives the lifting frame 22 to descend, due to the action of gravity, the bottom mounting frame 23 keeps a certain distance from the lifting block 241 all the time before abutting against the positioning unit, namely, the limiting head 2421 is lapped on the large hole bottom surface of the stepped hole of the lifting block 241, at the moment, because the bottom mounting frame 23 and the lifting frame 22 are movably connected, the position of the bottom mounting frame 23 in the horizontal plane is slightly deviated from the target position, when the bottom mounting frame 23 descends to abut against the positioning unit, the positioning pin 133 and the positioning pin hole 2313 are mutually matched and connected, the positioning pin 133 of the conical surface plays a certain guiding role, and when the small deviation exists between the axis of the positioning pin 133 and the positioning pin hole 2313, the positioning pin 133 and the positioning pin hole 2313 are also more beneficial, in the process, the limiting head 2421 at the upper end of the lifting pin 242 is separated from the lifting block 241 continuously, the lifting block 241 is subsequently pressed downwards by the lifting block 241 to be applied to the bottom mounting frame 23 by the downward pressing spring 243, the lifting driving device drives the lifting frame 22 to move downwards, so that the lifting block 241 is pressed to the bottom mounting frame 23 to the target position, and the positioning pin 243 is pressed against the bottom surface of the bottom mounting frame 23 continuously.

Compared with the prior art, the positioning and limiting of the bottom mounting frame 23 by the lifting frame 22 is changed from rigidity to flexibility, the positioning and limiting of the bottom mounting frame 23 mainly depend on the positioning unit arranged on the base 1, and the positioning block I131 and the positioning block II132 are arranged at the side of the printing medium and are unchanged relative to the position of the printing medium, so that when the lifting frame is lifted to adjust the height of the spray head, compared with the mechanical structure relation positioning between the bottom mounting frame 23 and the lifting frame 22 and the height positioning of the bottom mounting frame by the lifting driving device in the prior art, the positioning and limiting of the positioning unit in the embodiment are more accurate and stable, have no assembly error and transmission error, and do not need manual debugging in secondary positioning; in the transportation process, the positions of the positioning block I131 and the positioning block II132 are not changed, so that after the transportation is finished, the bottom mounting frame 23 can be accurately positioned through the positioning unit, the time cost and the labor cost for debugging and correcting, which are increased due to inaccurate positioning of the spray head, are saved, the delay of the printing production process is avoided, and the customer satisfaction is improved.

Further, the bottom mounting frame 23 is formed by surrounding a side support plate 231 disposed at a left-right interval and a lateral support plate 232 disposed at a front-rear interval, and the groove 2312 and the mounting hole 2311 are disposed on the side support plate 231.

Further, the positioning pin holes 2313 are provided on the bottom surface of the side support plate 231.

Further, the printing modules 25 are disposed in a plurality of spaces surrounded by the side support plates 231 and the lateral support plates 232, and the bottom of the printing module 25 is provided with a nozzle.

Further, the paper feeding mechanism 11 includes a supporting wall plate 111 disposed at a front-back interval, and the positioning block I131 and the positioning block II132 are mounted on an inner side surface of the supporting wall plate 111.

It should be noted that the foregoing detailed description is exemplary and is intended to provide further explanation of the utility model. Unless defined otherwise, all technical and scientific terms used herein have the same meaning as commonly understood by one of ordinary skill in the art to which this application belongs.

It is noted that the terminology used herein is for the purpose of describing particular embodiments only and is not intended to be limiting of exemplary embodiments according to the present application. As used herein, the singular is intended to include the plural unless the context clearly indicates otherwise. Furthermore, it will be further understood that the terms "comprises" and/or "comprising," when used in this specification, specify the presence of stated features, steps, operations, devices, components, and/or groups thereof.

It should be noted that the terms "first," "second," and the like in the description and claims of the present application and the above figures are used for distinguishing between similar objects and not necessarily for describing a particular sequential or chronological order. It is to be understood that the terms so used are interchangeable under appropriate circumstances such that the embodiments of the application described herein are capable of operation in sequences other than those illustrated or otherwise described herein.

Furthermore, the terms "comprise" and "have," as well as any variations thereof, are intended to cover a non-exclusive inclusion. For example, a process, method, system, article, or apparatus that comprises a list of steps or elements is not necessarily limited to those elements but may include other steps or elements not expressly listed or inherent to such process, method, article, or apparatus.

Spatially relative terms, such as "above … …," "above … …," "upper surface at … …," "above," and the like, may be used herein for ease of description to describe one device or feature's spatial location relative to another device or feature as illustrated in the figures. It will be understood that the spatially relative terms are intended to encompass different orientations in use or operation in addition to the orientation depicted in the figures. For example, if the device in the figures is turned over, elements described as "above" or "over" other devices or structures would then be oriented "below" or "beneath" the other devices or structures. Thus, the exemplary term "above … …" may include both orientations of "above … …" and "below … …". The device may also be positioned in other different ways, such as rotated 90 degrees or at other orientations, and the spatially relative descriptors used herein interpreted accordingly.

In the above detailed description, reference is made to the accompanying drawings, which form a part hereof. In the drawings, like numerals typically identify like components unless context indicates otherwise. The illustrated embodiments described in the detailed description, drawings, and claims are not meant to be limiting. Other embodiments may be utilized, and other changes may be made, without departing from the spirit or scope of the subject matter presented herein.

The above description is only of the preferred embodiments of the present utility model and is not intended to limit the present utility model, but various modifications and variations can be made to the present utility model by those skilled in the art. Any modification, equivalent replacement, improvement, etc. made within the spirit and principle of the present utility model should be included in the protection scope of the present utility model.

Claims (10)

1. A printer head positioning device, characterized in that: including printer head body (2), printer head body (2) include main frame (21) and lift frame (22), main frame (21) fixed mounting is on base (1), lift frame (22) with be connected through lift drive between main frame (21), lift drive is used for the drive lift frame (22) reciprocates, the bottom of lifting frame (22) is equipped with end installation frame (23), end installation frame (23) are used for installing printing module (25), lift frame (22) with be equipped with hoist device (24) between end installation frame (23), end installation frame (23) are through hoist device (24) with lift frame (22) swing joint, be equipped with paper feed mechanism (11) on base (1), be located the side position of print medium on paper feed mechanism (11) and be equipped with the positioning unit, the positioning unit is used for right end installation frame (23) are located and spacing apart from the height of print medium.

2. A printer head positioning apparatus as claimed in claim 1, wherein: hoist device (24) are including hanging piece (241), peg (242) and spring (243), hang piece (241) install respectively on the medial surface of interior left side board (222) and interior right side board (223) of lifting frame (22), the lower tip of peg (242) with end mounting frame (23) fixed connection, the upper end of peg (242) wear to locate in hanging piece (241) and can be relative hanging piece (241) reciprocates, spring (243) cover are located the outside of peg (242) and lie in between hanging piece (241) and end mounting frame (23).

3. A printer head positioning apparatus as claimed in claim 2, wherein: the lifting block (241) is provided with a stepped hole (2411), the upper end of the lifting nail (242) is provided with a limiting head (2421), the lower end of the lifting nail is provided with a threaded part (2422), the lifting nail (242) is arranged in the stepped hole (2411) in a penetrating mode, the limiting head (2421) is arranged in a large hole at the upper end of the stepped hole (2411), and the lifting nail (242) is fixedly connected with the bottom mounting frame (23) through the threaded part (2422).

4. A printer head positioning apparatus as claimed in claim 2, wherein: grooves (2312) are formed in the left side and the right side of the bottom mounting frame (23) respectively, the grooves (2312) are used for accommodating the lower end portions of the springs (243), mounting holes (2311) are formed in the center positions of the grooves (2312), and the lower end portions of the hanging nails (242) are mounted in the mounting holes (2311).

5. A printer head positioning apparatus as claimed in claim 1, wherein: the positioning unit comprises a positioning block I (131) and a positioning block II (132), wherein the positioning block I (131) is respectively provided with a positioning pin (133) and a positioning nail (134), the positioning pin (133) is used for positioning and limiting the position of the bottom mounting frame (23), and the positioning nail (134) is used for limiting the lowest position of the bottom mounting frame (23) away from a printing medium.

6. A printer head positioning apparatus as claimed in claim 5, wherein: the number of the positioning blocks I (131) and the number of the positioning blocks II (132) are two respectively, wherein the two positioning blocks I (131) are respectively arranged on the left front side and the right rear side of the paper feeding mechanism (11), and the two positioning blocks II (132) are respectively arranged on the left rear side and the right front side of the paper feeding mechanism (11).

7. A printer head positioning apparatus as claimed in claim 5, wherein: the bottom of the bottom mounting frame (23) is provided with a positioning pin hole (2313) matched with the positioning pin (133), and the positioning pin hole (2313) is used for accommodating the positioning pin (133).

8. A printer head positioning apparatus as claimed in claim 5, wherein: the paper feeding mechanism (11) comprises supporting wallboards (111) which are arranged at intervals front and back, and the positioning block I (131) and the positioning block II (132) are arranged on the inner side surface of the supporting wallboards (111).

9. A printer head positioning apparatus as claimed in claim 1, wherein: the lifting driving device comprises a motor (261) fixedly mounted on the main frame (21), a screw rod (262) is arranged at the output end of the motor (261), a screw nut (265) is sleeved on the screw rod (262), and the screw nut (265) is fixedly connected with the lifting frame (22).

10. A printer head positioning apparatus as claimed in claim 9, wherein: the motor (261) is installed on the motor installation plate (264), the motor installation plate (264) is fixedly installed on the main frame (21), the screw (265) is installed on the screw seat (263), and the screw seat (263) is fixedly installed on the lifting frame (22).