CN212043148U

CN212043148U - Dotting type engraving machine

Info

Publication number: CN212043148U
Application number: CN202020553286.7U
Authority: CN
Inventors: 王基月; 朱永刚; 郑喜贵; 王桂录; 刘军; 张玉华
Original assignee: Zhengzhou University of Science and Technology
Current assignee: Zhengzhou University of Science and Technology
Priority date: 2020-04-15
Filing date: 2020-04-15
Publication date: 2020-12-01
Anticipated expiration: 2030-04-15

Abstract

The utility model relates to a dotting type engraving machine, which effectively solves the problem that the existing engraving machine cannot screen leftover materials and metal scraps generated when engraving and cutting metal plates, so that the later treatment is more inconvenient; the technical scheme comprises the following steps: this dotting type engraver can sieve produced leftover bits and pieces and metal sweeps when carving sheet metal, has avoided the emergence of a large amount of metal leftover bits and pieces condition together that mixes, for later stage workman to the arrangement of sculpture waste material, retrieve and improved great facility, also alleviateed workman's work burden.

Description

Dotting type engraving machine

Technical Field

The utility model relates to a laser engraving technical field specifically is a dotting type engraver.

Background

Dotting carving is to carve corresponding figures and structures on metal, plastic or wood under the control of a numerical control computer, and is generally realized by a laser carving machine in the general industry, which belongs to an advanced device for carving materials to be carved by laser, because the laser carving has wider application range, higher carving precision and quicker carving speed, and compared with the traditional manual carving mode, the laser carving can also achieve fine carving effect which is not inferior to the technological level of manual carving, therefore, the application of the laser carving machine at present gradually replaces the traditional carving device and mode;

however, when the existing laser engraving machine engraves some materials, such as metal plates, some engraving wastes are easily generated, including metal scraps and metal scraps cut by laser, when the wastes are collected, the wastes are often mixed together, and since the scraps with large volume can be recycled, workers at the later stage need to screen the mixed engraving wastes, however, a large amount of engraving wastes are concentrated together and are screened inconveniently, thereby greatly increasing the workload of the workers;

in view of the above, we provide a dotting type engraving machine for solving the above problems.

SUMMERY OF THE UTILITY MODEL

To the above situation, for overcoming prior art's defect, the utility model provides a beat point type engraver, this beat point type engraver can sieve produced leftover bits and metal sweeps when carving sheet metal, has avoided the emergence of a large amount of metal leftover bits and metal sweeps condition together that mixes, for later stage workman to the arrangement of sculpture waste material, retrieve and improved great facility, also alleviateed workman's work burden.

A dotting type engraving machine comprises a rack, wherein an engraving rod is longitudinally slidably mounted in the rack, a laser head is transversely slidably mounted on an engraving plate, and the dotting type engraving machine is characterized in that a bearing net is mounted below the engraving rod in the rack, a screen frame is vertically slidably mounted in the rack below the bearing net, two screening devices are longitudinally rotatably mounted in the screen frame, a telescopic spring is connected between the bearing net and the rack, a positioning device for positioning the bearing net is arranged on the rack, cams which coaxially rotate are respectively arranged on two transverse sides in the rack below the screen frame, and a transmission device is connected to a cam shaft and is driven by a motor;

two horizontal one side of sieving mechanism is equipped with coaxial pivoted upset gear and two upset gear intermeshing with it respectively, and one of them upset gear is connected with the reciprocal rack of vertical slidable mounting in the frame through worm gear transmission, reciprocal rack cooperation has the half-gear and the half-gear that rotate the installation in the frame to be connected with transmission, can drive the cam through transmission when the motor corotation, can drive half-gear when the motor reversal.

Preferably, the sieving mechanism includes the screen cloth frame and sets up the screen cloth in the screen cloth frame, one of them upset gear coaxial rotation has the second worm wheel, and worm gear transmission just rotates the first worm of installing on the screen cloth frame with the meshing of second worm wheel including arranging the frame in outside, axial slip has transmission shaft and the inherent first worm wheel of cover on the transmission shaft in the first worm, first worm wheel cooperation has the second worm of rotating and installing in the frame, second worm coaxial rotation have with reciprocal tooth frame complex reciprocating gear.

Preferably, a plurality of tooth systems meshed with the reciprocating gear are fixed on the lower end face of the reciprocating gear frame.

Preferably, the transmission means comprises: with camshaft, half gear shaft connection triangle belt pulley group and triangle belt pulley group through motor drive, triangle belt pulley group is including respectively with cam, the coaxial pivoted one-way band pulley of half gear, two the installation of one-way band pulley satisfies: when the motor rotates forwards, the cam can be driven to rotate through the triangular belt, and when the motor rotates backwards, the half gear can be driven to rotate.

Preferably, the two unidirectional belt wheels are respectively rotatably mounted on a half gear shaft and a cam shaft corresponding to the two unidirectional belt wheels, a plurality of ratchets are arranged on the inner circular surface of each unidirectional belt wheel, pawls are rotatably mounted on the half gear shaft and the cam shaft, and elastic rubber blocks which are abutted against the pawls are fixed on the half gear shaft and the cam shaft.

Preferably, the positioning device comprises positioning columns which are arranged on the two longitudinal sides of the rack in a longitudinal sliding mode, positioning springs are connected between the positioning columns and the rack, and positioning holes matched with the positioning columns are formed in the screen frame.

Preferably, the screen frame up end is provided with the baffle and the horizontal interval in the vertical both sides of screen frame lower extreme is provided with the accessory plate with the vertical sliding fit installation of screen frame, be connected with expanding spring and accessory plate up end between accessory plate and the screen frame and contradict in screen frame terminal surface down, the accessory plate stretches out screen frame one end and carries out the radius angle setting.

The beneficial effects of the technical scheme are as follows:

(1) the dotting type engraving machine can screen leftover materials and metal scraps generated in the process of engraving metal plates, avoids the situation that a large amount of metal leftover materials and metal scraps are mixed together, provides great convenience for later-stage workers to tidy and recycle engraving waste materials, and also reduces the workload of the workers;

(2) we will treat that glyptic sheet metal fixes on the bearing net in this scheme us, carves sheet metal through the laser head afterwards, the cutting, the effect of bearing sheet metal has been played on the one hand in the setting of bearing net, on the other hand makes the metal sweeps that produces when carving by laser head sculpture, the great metal leftover bits of volume under the cutting and laser head through the great net clearance on the bearing net, on the sieve that drops to the below to in it sieves.

Drawings

FIG. 1 is a schematic view of the overall structure of the present invention;

FIG. 2 is a cross-sectional side view of the inner part of the frame of the present invention;

FIG. 3 is a schematic bottom view of the local structure of the present invention;

FIG. 4 is a front view of the frame and the screen frame of the present invention;

FIG. 5 is a schematic view of the matching relationship between the laser head and the transverse rod of the present invention;

FIG. 6 is an enlarged view of the structure at the position A of the present invention;

FIG. 7 is an optical diagram of the triangular pulley set, the reciprocating rack, and the worm gear transmission device of the present invention;

FIG. 8 is a schematic view of the fit relationship between the screen frame and the screen frame of the present invention;

FIG. 9 is an enlarged view of the structure at B of the present invention;

FIG. 10 is a schematic view showing the relationship between the reciprocating rack and the triangular pulley set;

FIG. 11 is a schematic bottom view of the overall structure of the present invention;

FIG. 12 is a schematic structural view of the two screen frames of the present invention rotating relatively;

fig. 13 is a schematic view of the internal structure of the screen frame of the present invention after partial section;

FIG. 14 is a schematic view showing the connection relationship between the unidirectional pulley, the V-belt, the half gear shaft and the cam shaft of the present invention;

fig. 15 is a schematic view of the matching relationship between the one-way belt wheel and the shaft of the present invention.

Detailed Description

The foregoing and other technical matters, features and effects of the present invention will be apparent from the following detailed description of the embodiments, which is to be read in connection with the accompanying drawings of fig. 1 to 15. The structural contents mentioned in the following embodiments are all referred to the attached drawings of the specification.

Exemplary embodiments of the present invention will be described below with reference to the accompanying drawings.

First embodiment, this embodiment provides a dotting type engraving machine, referring to fig. 1, including a frame 1 and we install universal wheels with self-locking function at the bottom of the frame 1, which facilitates the movement of the device, further improves the flexibility of the engraving machine, we install longitudinal rods 30 on both sides of the frame 1 in a rotating manner and install the engraving rods 2 on the two longitudinal rods 30 in a longitudinally sliding fit manner, the engraving rods 2 and one of the longitudinal rods 30 are in a threaded fit manner and the longitudinal rod 30 in a threaded fit manner with the engraving rod 2 is driven by a longitudinal sliding motor (we can fixedly install the longitudinal sliding motor on the frame 1, the above installation structure is a conventional design manner and is not described here), we drive the engraving rod 2 to move in the longitudinal direction by the longitudinal sliding motor, we install a transverse rod 31 on the engraving rod 2 in a rotating manner and install a laser head seat in a threaded fit manner with the transverse rod 31 on the engraving rod 2 in a sliding manner, laser head 3 fixed mounting is on the laser headstock, horizontal pole 31 is through being fixed in the horizontal motor drive that slides on the sculpture pole 2 (being conventional structure setting, no longer showing in the picture), we install control panel 32 and be provided with the control unit in the control panel 32 on frame 1, horizontal motor, the vertical motor that slides all with the control unit electric connection, laser head 3 is connected with the laser instrument and the laser instrument is through the control unit control, vertical motor, the horizontal motor that slides and the equal electric connection of laser instrument have external power supply, we input corresponding procedure in advance on control panel 32, then control vertical motor, horizontal motor that slides (vertical motor, horizontal motor that slides mutually support and drive laser head 3 and move in X, Y planes) and the laser instrument work in coordination, accomplish jointly the sculpture to sheet metal, Cutting;

a supporting net 4 is arranged below the carving rod 2 in the machine frame 1, and when in carving, a metal plate to be processed is placed on the supporting net 4 (preferably, a clamping device for positioning the metal plate can be arranged in the machine frame 1. the scheme provides the clamping device which can adopt an eccentric clamping mechanism, and the eccentric clamping mechanisms are respectively arranged at the two transverse sides of the supporting net 4, so that the clamping effect on the two transverse side walls of the metal plate is realized, and the position of the metal plate is prevented from moving when in carving);

referring to fig. 4, a screen frame 5 is vertically and slidably mounted in a frame 1 below a supporting net 4, two screening devices (as shown in fig. 12) are mounted in the screen frame 5, a telescopic spring 29 is connected between the supporting net 4 and the frame 1, and a positioning device for positioning the supporting net 4 is arranged on the frame 1 (when the positioning device positions the screen frame 5, the upper end face of the screen frame 5 abuts against a cam 7, as shown in fig. 4), coaxially rotating cams 7 are respectively arranged on two transverse sides in the frame 1 below the screen frame 5, a cam shaft 36 is connected with a transmission device, the transmission device is driven by a motor 8, and after an engraving machine finishes engraving a metal plate, metal leftover materials and metal scraps generated by engraving fall onto the screening devices through the supporting net 4;

referring to fig. 8 and 12, the two screening devices are respectively and longitudinally rotatably mounted on the screen frame 5, and one lateral side of each screening device is respectively provided with a turnover gear 9 which coaxially rotates with the screening device, and the two turnover gears 9 are mutually meshed, one turnover gear 9 is connected with a reciprocating rack 10 which is longitudinally slidably mounted on the frame 1 through a worm gear transmission device, the reciprocating rack 10 is matched with a half gear 11 which is rotatably mounted on the frame 1, and the half gear 11 is connected with the transmission device, when the motor 8 rotates forwards, the cam 7 can be driven to rotate through the transmission device (at this time, the motor 8 cannot drive the half gear 11 to rotate), and when the motor 8 rotates backwards, the half gear 11 can be driven to rotate (at this time, the motor 8 cannot drive the cam 7 to rotate;

at the moment, the motor 8 is controlled by the motor 8 controller to rotate positively and drive the two cams 7 to rotate through the transmission device, the two cams 7 rotate under the driving of the motor 8 and enable the screen frame 5 to have a tendency of moving upwards, at the moment, the positioning device loses the positioning function on the screen frame 5, and the screen frame 5 moves upwards and enables the expansion spring 29 to be stretched along with the continuous rotation of the cams 7, when the screen frame 5 moves to the highest point under the driving of the cams 7, the screen frame 5 moves downwards under the action of the expansion spring 29, and then the process is repeated, namely, the motor 8 drives the two cams 7 to rotate quickly, so that the screen frame 5 is driven to do quick reciprocating movement vertically, and metal scraps falling onto the screening device fall off from the screening device (the motor 8 controller controls the motor 8 to rotate positively for N whole circles and then stop working, so that the screen frame 5 can be positioned as shown in the attached drawing 4) again, when screening metal scraps and metal scraps, a metal scrap receiving box is placed below the screening device, and the screening device moves vertically and rapidly in a reciprocating manner along with the screen frame 5, so that certain shaking is generated, all the metal scraps mixed with the metal scraps fall into the metal scrap receiving box, and at the moment, the metal scraps with larger volume are still positioned on the screening device;

initially, the two screening devices are in a folded state, as shown in fig. 4, then the motor 8 is controlled by the motor 8 controller to rotate reversely, so that the transmission device drives the half gear 11 to rotate, the half gear 11 drives the reciprocating rack 10 engaged with the half gear, and the motor 8 controller controls the motor 8 to stop working (the motor 8 controller is an integrated circuit which actively works to control the motor 8 to work according to the set direction, speed, angle and response time) when the motor 8 drives the reciprocating rack 10 to move to the farthest distance to one side in the longitudinal direction, and meanwhile, the reciprocating rack 10 drives the two screening devices to rotate downwards through the worm gear connected with the motor (the worm gear drives the two turnover gears 9 to rotate so that the two screening devices synchronously rotate downwards) and is in a position shown in fig. 11 (at this time, the two screening devices are opened), at the moment, metal leftover materials with large volume on the screening device roll down from the screening device, a metal leftover material receiving box is placed below the screening device and used for collecting recyclable metal leftover materials, after the metal leftover materials on the screening device completely fall off, the motor 8 is controlled by a motor 8 controller to rotate reversely and drive a reciprocating toothed frame 10 to move to the other longitudinal side, the motor 8 stops working, and at the moment, the two screening devices recover to an initial folding state, namely as shown in the attached drawing 4.

In the second embodiment, on the basis of the first embodiment, referring to fig. 8, the screening device comprises a screen frame 12 and a screen 13 arranged in the screen frame 12, referring to fig. 9, wherein one overturning gear 9 coaxially rotates with a second worm wheel 34, referring to fig. 6, the worm-and-gear transmission device comprises a first worm 14 which is arranged outside the frame 1 and rotatably mounted on the screen frame 5 and meshed with the second worm wheel 34, a transmission shaft 33 axially slides in the first worm 14, and a first worm wheel 15 (as shown in fig. 9) is fixedly sleeved on the transmission shaft 33, the first worm wheel 15 is matched with a second worm 16 (as shown in fig. 7) rotatably mounted on the frame 1, and the second worm 16 coaxially rotates with a reciprocating gear 17 matched with the reciprocating rack 10;

when the motor 8 rotates reversely, the half gear 11 is driven by the transmission device to drive the reciprocating gear frame 10 to move, so that the reciprocating gear frame 10 drives the second worm 16 to rotate through the reciprocating gear 17 meshed with the reciprocating gear frame, the second worm 16 rotates and further drives the transmission shaft 33 to rotate through the first worm wheel 15 meshed with the second worm wheel, so that the first worm 14 axially and slidably mounted with the transmission shaft 33 is driven to rotate and further drives the two turnover gears 9 to rotate in opposite directions through the second worm wheel 34 meshed with the turnover gears, and therefore the effect of driving the two screen frames 12 to be folded and opened is achieved, the half gear 11 drives the reciprocating gear frame 10 to reciprocate in the longitudinal direction under the driving of the motor 8, and the effect of driving the two screen frames 12 to be folded and opened is achieved;

because the transmission shaft 33 and the first worm 14 are installed in an axial sliding fit manner, when the motor 8 drives the cam 7 to drive the screen frame 5 to reciprocate vertically, the transmission shaft 33 is always matched with the first worm 14, because the motor 8 transmits power to the first worm 15 through the second worm 16, and the first worm 15 drives the two screen frames 12 to rotate through the transmission shaft 33, the first worm 14 and the second worm 34, due to the one-way transmission principle of the worm gears, when the motor 8 drives the screen frame 5 to reciprocate rapidly vertically, the two screen frames 12 rotatably installed in the screen frame 5 cannot rotate.

In the third embodiment, on the basis of the second embodiment, a plurality of tooth systems 18 engaged with the reciprocating gear 17 are fixed on the lower end surface of the reciprocating gear frame 10, and when the half gear 11 drives the reciprocating gear frame 10 to move in the longitudinal direction, the plurality of tooth systems 18 drive the reciprocating gear 17 to rotate.

In a fourth embodiment, on the basis of the third embodiment, referring to fig. 10, the transmission device includes: the triangle belt 20 wheel set and the triangle belt 20 wheel set are connected with the cam shaft 36 and the half gear shaft 35 and driven by the motor 8, the triangle belt 20 wheel set comprises the one-way belt wheel 19 which coaxially rotates with the cam 7 and the half gear 11 respectively (refer to the schematic diagram of fig. 15, the one-way belt wheel 19 and the corresponding shaft installation matching relation), and the two-way belt wheel 19 is installed and satisfied: the cam 7 can be driven to rotate through the V-belt 20 when the motor 8 rotates forwards, and the half gear 11 can be driven to rotate when the motor 8 rotates backwards;

when the motor 8 is controlled to rotate forwards by the motor 8 controller, the cam shaft 36 can be driven to rotate by the motor 8 through the V-belt 20, the half gear shaft 35 cannot be driven to rotate by relative rotation (slipping) generated between the one-way belt wheel 19 matched with the half gear shaft 35 and the half gear shaft 35 at the moment, when the motor 8 is controlled to rotate backwards by the motor 8 controller, the half gear shaft 35 is driven to rotate by the motor 8 through the V-belt 20, and the cam shaft 36 cannot be driven to rotate by relative rotation (slipping) generated between the one-way belt wheel 19 matched with the cam shaft 36 and the cam shaft 36 at the moment.

Fifth embodiment, on the basis of the fourth embodiment, specifically, the mounting manner between the two one-way belt wheels 19 and the half gear shafts 35 and the cam shafts 36 is as shown in fig. 14, the two one-way belt wheels 19 are respectively rotatably mounted on the half gear shafts 35 and the cam shafts 36 corresponding thereto, referring to fig. 15, a plurality of ratchets 21 are arranged on the inner circumferential surface of the one-way belt wheel 19, pawls 22 are rotatably mounted on the half gear shafts 35 and the cam shafts 36, elastic rubber blocks 23 abutting against the pawls 22 are fixed on the half gear shafts 35 and the cam shafts 36, when the motor 8 rotates forward, we set to drive the V-belt 20 to rotate clockwise as shown in fig. 14, and further drive the cam shafts 36 to rotate through the one-way belt wheel 19 rotatably mounted with the cam shafts 36, at this time, the one-way belt wheel 19 rotatably mounted with the half gear shafts 35 and the half gear shafts 35 rotate relatively, namely, the one-way belt wheel 19 can not drive the half gear shaft 35 to rotate in an idle running manner, when the motor 8 rotates reversely, the v-belt 20 is driven to rotate in the counterclockwise direction shown in fig. 14, that is, the one-way belt wheel 19 which is rotatably mounted and matched with the half gear shaft 35 is synchronously driven to rotate in the counterclockwise direction, so that the half gear shaft 35 is driven to rotate through the structure of the matched ratchet 21 and the matched pawl 22, and at this time, the one-way belt wheel 19 which is rotatably mounted and matched with the cam shaft 36 and the cam shaft 36 can not drive the cam shaft 36 to rotate;

in this embodiment, the elastic rubber block 23 fixed to the half gear shaft 35 and the cam shaft 36 and abutting against the ratchet 22 has an effect of restoring the ratchet 22.

Sixth embodiment, on the basis of the first embodiment, the positioning device includes positioning pillars 24 longitudinally slidably installed on two longitudinal sides of the frame 1, and a positioning spring 25 is connected between the positioning pillars 24 and the frame 1, the screen frame 5 is provided with positioning holes 26 matched with the positioning pillars 24, when the screen frame 5 is in a positioned state, the positioning pillars 24 are inserted into the corresponding positioning holes 26 under the action of the positioning springs 25 to position the screen frame 5, and at this time, the lower end surface of the screen frame 5 abuts against the cam 7, when the cam 7 is driven by the motor 8 to rotate, the cam 7 forces the screen frame 5 to move upward and enables the positioning pillars 24 inserted into the positioning holes 26 to be ejected from the positioning holes 26 by upward pressing force from the screen frame 5, we perform round-cornered setting on one end of the head portions of the positioning pillars 24 to facilitate the ejection from the positioning holes 26, along with the screen frame 5 moving vertically to and fro, the positioning column 24 is continuously inserted into the positioning hole 26 and continuously withdrawn from the positioning hole 26 under the action of the positioning spring 25, so that after the motor 8 rotates forwards for N whole circles under the action of the motor 8 controller to stop working, the positioning column 24 is inserted into the positioning hole 26 again to realize the positioning of the screen frame 5.

Seventh embodiment, on the basis of the second embodiment, referring to fig. 13, preferably, a baffle 27 is disposed on the upper end surface of the screen frame 5, two screen frames 12 are rotatably mounted in the screen frame 5, when the two screen frames 12 are in the closed state, a side wall of the screen frame 12 close to the baffle 27 is spaced from a side wall of the screen frame 5 below the baffle 27, and the upper end surface of the screen frame 12 abuts against the lower end surface of the baffle 27, an auxiliary plate 28 slidably fitted with the screen frame 5 is connected to the screen frame 5 below the baffle 27 through a telescopic spring 29, when the two screen frames 12 are in the closed state, the lower end surface of the screen frame 12 abuts against the auxiliary plate 28 at the position of the fillet, the baffle 27 and the auxiliary plate 28 are disposed to better limit the two screen frames 12 when the screen frame 5 reciprocates in the vertical direction, so as to avoid the screen frame 5 from reciprocating in the vertical direction, when the two screen frames 12 are driven by the motor 8 to be opened, the two screen frames 12 rotate downwards and force the auxiliary plate 28 to contract into the screen frame 5, so that the expansion spring 29 is compressed to store energy, when the two screen frames 12 are folded, the upper end surface of the screen frame 12 abuts against the inverted corner position of the auxiliary plate 28 and force the auxiliary plate 28 to contract into the screen frame 5, and when the two screen frames 12 are completely folded, the auxiliary plate 28 abuts against the lower end surface of the screen frame 12 again under the action of the expansion spring 29.

The dotting type engraving machine can screen leftover materials and metal scraps generated in the process of engraving metal plates, avoids the situation that a large amount of metal leftover materials and metal scraps are mixed together, provides great convenience for later-stage workers to tidy and recycle engraving waste materials, and also reduces the workload of the workers;

we will treat that glyptic sheet metal fixes on bearing net 4 in this scheme, carve sheet metal through laser head 3 afterwards, the cutting, bearing net 4's setting has played bearing sheet metal's effect on the one hand, on the other hand makes the metal sweeps that produces when carving by laser head 3, the great metal leftover bits of volume under the cutting and laser head 3 through the great net clearance on bearing net 4, drop to the screen cloth 13 of below on to in order to sieve it.

The above description is only for the purpose of illustration, and it should be understood that the present invention is not limited to the above embodiments, and various modifications conforming to the spirit of the present invention are within the scope of the present invention.

Claims

1. A dotting type engraving machine comprises a frame (1), wherein an engraving rod (2) is longitudinally installed in the frame (1) in a sliding manner, a laser head (3) is transversely arranged on an engraving plate in a sliding manner, it is characterized in that a bearing net (4) is arranged below the carving rod (2) in the frame (1), a screen frame (5) is vertically and slidably arranged in the frame (1) below the bearing net (4), and two screening devices are longitudinally and rotatably arranged in the screen frame (5), an extension spring (29) is connected between the bearing net (4) and the rack (1), a positioning device for positioning the bearing net (4) is arranged on the rack (1), cams (7) which rotate coaxially are respectively arranged on two transverse sides in the rack (1) below the screen frame (5), a transmission device is connected with the cam shaft (36), and the transmission device is driven by a motor (8);

two horizontal one side of sieving mechanism is equipped with coaxial pivoted upset gear (9) and two upset gears (9) intermeshing with it respectively, and one of them upset gear (9) is connected with reciprocal tooth frame (10) of longitudinal sliding installation on frame (1) through worm gear transmission, reciprocal tooth frame (10) cooperation has half gear (11) and half gear (11) of rotation installation on frame (1) to be connected with transmission, can drive cam (7) and rotate through transmission when motor (8) corotation, can drive half gear (11) and rotate when motor (8) reversal.

2. The dotting engraving machine according to claim 1, characterized in that the screening device comprises a screen frame (12) and a screen (13) arranged in the screen frame (12), wherein one of the turning gears (9) coaxially rotates with a second worm gear (34), the worm gear comprises a first worm (14) which is arranged outside the frame (1) and rotatably mounted on the screen frame (5) and meshed with the second worm gear (34), a transmission shaft (33) axially slides in the first worm (14) and a first worm gear (15) is fixedly sleeved on the transmission shaft (33), the first worm gear (15) is matched with a second worm (16) rotatably mounted on the frame (1), and the second worm (16) coaxially rotates with a reciprocating gear (17) matched with the reciprocating gear frame (10).

3. The dotting engraving machine according to claim 2, characterized in that the lower end face of the reciprocating toothed frame (10) is fixed with a plurality of tooth systems (18) engaged with the reciprocating gear (17).

4. The dotting engraving machine according to claim 3, characterized in that said transmission means comprise: be connected triangle belt (20) wheelset and triangle belt (20) wheelset through motor (8) drive with camshaft (36), half gear shaft (35), triangle belt (20) wheelset is including respectively with cam (7), half gear (11) coaxial rotation's one-way band pulley (19), two the installation of one-way band pulley (19) satisfies: when the motor (8) rotates forwards, the cam (7) can be driven to rotate through the triangle belt (20), and when the motor (8) rotates backwards, the half gear (11) can be driven to rotate.

5. The dotting type engraving machine according to claim 4, characterized in that two one-way belt wheels (19) are rotatably mounted on the corresponding half gear shaft (35) and cam shaft (36), respectively, the inner surface of the one-way belt wheel (19) is provided with a plurality of ratchets (21), pawls (22) are rotatably mounted on the half gear shaft (35) and cam shaft (36), and elastic rubber blocks (23) abutting against the pawls (22) are fixed on the half gear shaft (35) and cam shaft (36).

6. The dotting engraving machine according to claim 1, characterized in that the positioning device comprises positioning columns (24) longitudinally slidably mounted on two longitudinal sides of the frame (1), a positioning spring (25) is connected between the positioning columns (24) and the frame (1), and positioning holes (26) matched with the positioning columns (24) are formed in the screen frame (5).

7. The dotting type engraving machine according to claim 2, wherein the upper end surface of the screen frame (5) is provided with a baffle plate (27), the lower end of the screen frame (5) is provided with auxiliary plates (28) which are arranged at two longitudinal sides of the screen frame (5) at intervals, the auxiliary plates are longitudinally and slidably matched with the screen frame (5), a telescopic spring (29) is connected between the auxiliary plates (28) and the screen frame (5), the upper end surface of each auxiliary plate (28) abuts against the lower end surface of the screen frame (12), and the auxiliary plates (28) extend out of one end of the screen frame (5) to be chamfered.