阅读说明：本技术 一种机床主轴用装夹夹具 (Clamping fixture for machine tool spindle ) 是由 曹自洋 马振武 殷振 卢金斌 苗情 戴晨伟 潘杰 倪家伟 许威 朱译文 于 2021-09-27 设计创作，主要内容包括：本发明属于机床夹具技术领域,公开了一种机床主轴用装夹夹具,包括：主轴,所述主轴一端的中心处开设有定位盲孔,另一端与机床连接；负吸定位件,所述负吸定位件可配合插入至定位盲孔内,且负吸定位件的一端负吸连接有工件；均匀分布于主轴一端的三个圆柱形的夹柱,所述工件夹紧于三个夹柱之间,且每个夹柱均与主轴形成独立的偏心转动连接；综上,将负吸定位件负吸固定于工件的加工位置处,然后将负吸定位件插入定位盲孔内,以此实现主轴与工件之间的精准定位,接着利用三个可独立偏心转动的夹柱实现工件的夹紧固定,由此能在不改变刀具位置的前提下实现工件加工位置与刀具的精确对准,整体夹具操作简单、夹紧稳定且加工精度高。(The invention belongs to the technical field of machine tool fixtures, and discloses a clamping fixture for a machine tool spindle, which comprises: the center of one end of the main shaft is provided with a positioning blind hole, and the other end of the main shaft is connected with a machine tool; the negative suction positioning piece can be inserted into the positioning blind hole in a matching manner, and one end of the negative suction positioning piece is connected with a workpiece in a negative suction manner; the three cylindrical clamping columns are uniformly distributed at one end of the main shaft, the workpiece is clamped among the three clamping columns, and each clamping column is in independent eccentric rotation connection with the main shaft; in conclusion, the negative suction positioning piece is fixed at the machining position of the workpiece in a negative suction mode, then the negative suction positioning piece is inserted into the positioning blind hole, so that accurate positioning between the main shaft and the workpiece is achieved, then clamping and fixing of the workpiece are achieved by the aid of the three clamping columns capable of rotating independently and eccentrically, accurate alignment of the machining position of the workpiece and the cutter can be achieved on the premise that the position of the cutter is not changed, and the overall clamp is simple in operation, stable in clamping and high in machining accuracy.)

1. The utility model provides a clamping anchor clamps for lathe main shaft which characterized in that includes:

the center of one end of the main shaft (1) is provided with a positioning blind hole (2), and the other end of the main shaft is connected with a machine tool;

the negative suction positioning piece (3) can be inserted into the positioning blind hole (2) in a matching manner, and one end of the negative suction positioning piece (3) is connected with a workpiece (5) in a negative suction manner;

evenly distributed in three columniform clamp post (4) of main shaft (1) one end, work piece (5) press from both sides tightly between three clamp post (4), and every clamp post (4) all forms independent eccentric rotation with main shaft (1) and is connected.

2. The clamping fixture for the machine tool spindle according to claim 1, characterized in that: one end of each clamping column (4) is connected with a rotating motor (41), and the rotating motor (41) is embedded and fixed in the main shaft (1).

3. The clamping fixture for the machine tool spindle according to claim 2, characterized in that: a pressure sensor (42) is fixed to an outer wall of each of the clamping columns (4), and the rotary motor (41) stops the rotary drive in response to a detection value of the corresponding pressure sensor (42) exceeding a threshold value.

4. The clamping fixture for the machine tool spindle according to claim 1, wherein the negative suction positioning member (3) comprises:

a negative suction barrel (31) with one open end, wherein the open end of the negative suction barrel (31) is contacted with the workpiece (5);

the piston plate (32) is in sliding fit with the inside of the negative suction barrel (31), a threaded rod (33) is fixed on the piston plate (32), and the threaded rod (33) penetrates through the other end of the negative suction barrel (31).

5. The clamping fixture for the machine tool spindle according to claim 4, characterized in that:

a limiting spring (34) is connected between the piston plate (32) and the inner wall of the negative suction barrel (31), and the limiting spring (34) is used for limiting the opening end of the piston plate (32) far away from the negative suction barrel (31);

first through-hole has been seted up in the center department of threaded rod (33), bucket (31) opening intercommunication is inhaled with the burden to first through-hole, just the inside of first through-hole is provided with check valve (35), check valve (35) realize that the burden inhales the one-way switch-on of bucket (31) opening to threaded rod (33) direction.

6. The clamping fixture for the machine tool spindle according to claim 5, characterized in that:

a hollow valve seat (351) is fixed in the first through hole of the threaded rod (33), and the one-way valve (35) is installed inside the hollow valve seat (351);

a movable connecting rod (352) penetrates through the hollow valve seat (351), the connecting rod (352) is positioned on the outer side of the one-way valve (35), and a sealing sleeve (353) and a porous filter plate (354) are respectively fixed at two ends of the connecting rod (352) along the conduction direction of the one-way valve (35); the first through hole, the sealing sleeve (353) and the hollow valve seat (351) are sequentially communicated, and a positioning spring (355) is connected between the porous filter plate (354) and the hollow valve seat (351);

a second through hole is formed in one side of the first through hole, and the positioning spring (355) is used for driving the sealing sleeve (353) to be close to the hollow valve seat (351) and sealing between the first through hole and the second through hole is achieved.

7. The clamping jig for the machine tool spindle according to claim 4 or 6, characterized in that:

a limiting sleeve (36) is detachably screwed and connected to the outer part of the threaded rod (33), and the limiting sleeve (36) is used for limiting the sliding position of the piston plate (32) in the negative suction barrel (31).

8. The clamping jig for the machine tool spindle according to claim 4 or 6, characterized in that:

a first sealing ring (37) is sleeved at the opening end of the negative suction barrel (31), and the negative suction barrel (31) is in sealing contact with a workpiece (5) through the first sealing ring (37);

a second sealing ring (38) is fixed on the piston plate (32), and the second sealing ring (38) can be inserted into the first sealing ring (37) in a sealing mode.

9. The clamping fixture for the machine tool spindle according to claim 7, further comprising a cross-shaped structure of a calibration piece (6) matched with the negative suction positioning piece (3), wherein the calibration piece (6) comprises a main calibration plate (61) and three auxiliary calibration plates (62);

a sliding groove (63) is formed in the main calibration plate (61), the threaded rod (33) is in sliding fit with the sliding groove (63), and the diameter of the limiting sleeve (36) is larger than the width of the sliding groove (63);

a transparent scale is arranged in the middle of the auxiliary calibration plate (62).

10. The clamping fixture for the machine tool spindle according to claim 9, characterized in that: three extending parts (64) are formed at one end of the main calibration plate (61), three vertical plates (65) are correspondingly connected between the three extending parts (64) and the three auxiliary calibration plates (62) one by one, so that the three auxiliary calibration plates (62) are tightly attached to a workpiece (5), and a moving channel capable of accommodating the negative suction barrel (31) is formed between the main calibration plate (61) and the workpiece (5).

Technical Field

The invention belongs to the technical field of machine tool fixtures, and particularly relates to a clamping fixture for a machine tool spindle.

Background

At present, when a machine tool is used for processing a workpiece, a three-jaw chuck is mostly adopted for fixing the workpiece to be processed, three jaws which synchronously move along the radial direction are uniformly distributed on the three-jaw chuck, and the workpiece is clamped and positioned by the movement of the jaws; in this fixing method, after the workpiece is fixed, the spindle axis and the workpiece axis are mostly concentric, which is suitable for workpiece rotation machining, and if eccentric machining is required at the end of the workpiece, the position of the tool of the machine tool needs to be adjusted.

Disclosure of Invention

In view of the above, in order to solve the problems in the background art, the present invention provides a clamping fixture for a machine tool spindle, and the clamping fixture can effectively achieve workpiece clamping and eccentric machining without changing the position of a tool.

In order to achieve the purpose, the invention provides the following technical scheme:

a clamping fixture for a machine tool spindle comprises:

the center of one end of the main shaft is provided with a positioning blind hole, and the other end of the main shaft is connected with a machine tool;

the negative suction positioning piece can be inserted into the positioning blind hole in a matching manner, and one end of the negative suction positioning piece is connected with a workpiece in a negative suction manner;

the three cylindrical clamp posts are uniformly distributed at one end of the main shaft, the workpiece is clamped between the three clamp posts, and each clamp post is connected with the main shaft in an independent eccentric rotation mode.

Preferably, one end of each clamping column is connected with a rotating motor, and the rotating motor is embedded and fixed in the main shaft.

Preferably, a pressure sensor is fixed to an outer wall of each of the clamping posts, and the rotary motor stops the rotational driving in response to a detection value of the corresponding pressure sensor exceeding a threshold value.

Preferably, the negative suction positioning member includes:

the negative suction barrel is provided with an opening at one end, and the opening end of the negative suction barrel is contacted with the workpiece;

the piston plate is in sliding fit with the inside of the negative suction barrel, a threaded rod is fixed on the piston plate, and the threaded rod penetrates through the other end of the negative suction barrel.

Preferably, a limiting spring is connected between the piston plate and the inner wall of the negative suction barrel, and the limiting spring is used for limiting the opening end of the piston plate, which is far away from the negative suction barrel; the center department of threaded rod has seted up first through-hole, first through-hole and burden inhale bucket opening intercommunication, just the inside of first through-hole is provided with the check valve, the check valve realizes that the burden inhales the one-way switch-on of bucket opening to the threaded rod direction.

Preferably:

a hollow valve seat is fixed in the first through hole of the threaded rod, and the one-way valve is arranged in the hollow valve seat;

a movable connecting rod penetrates through the hollow valve seat, the connecting rod is positioned on the outer side of the one-way valve, and a sealing sleeve and a porous filter plate are respectively fixed at two ends of the connecting rod along the conduction direction of the one-way valve; the first through hole, the sealing sleeve and the hollow valve seat are sequentially communicated, and a positioning spring is connected between the porous filter plate and the hollow valve seat;

and a second through hole is formed in one side of the first through hole, and the positioning spring is used for driving the sealing sleeve to be close to the hollow valve seat and sealing between the first through hole and the second through hole.

Preferably, the external part of the threaded rod is detachably screwed with a limiting sleeve, and the limiting sleeve is used for limiting the sliding position of the piston plate in the negative suction barrel.

Preferably, a first sealing ring is sleeved at the opening end of the negative suction barrel, and the negative suction barrel is in sealing contact with the workpiece through the first sealing ring; and a second sealing ring is fixed on the piston plate and can be inserted into the first sealing ring in a sealing manner.

Preferably, the clamping fixture further comprises a calibration piece of a cross structure matched with the negative suction positioning piece, and the calibration piece comprises a main calibration plate and three auxiliary calibration plates; a sliding groove is formed in the main calibration plate, the threaded rod is in sliding fit in the sliding groove, and the diameter of the limiting sleeve is larger than the width of the sliding groove; and a transparent scale is arranged in the middle of the auxiliary calibration plate.

Preferably, three extending parts are formed at one end of the main calibration plate, three vertical plates are correspondingly connected between the three extending parts and the three auxiliary calibration plates one by one, so that the three auxiliary calibration plates are tightly attached to a workpiece, and a moving channel capable of accommodating the negative suction barrel is formed between the main calibration plate and the workpiece.

Compared with the prior art, the invention has the following beneficial effects:

(1) according to the invention, the negative suction positioning piece is fixed at the processing position of the workpiece in a negative suction manner, then the negative suction positioning piece is inserted into the positioning blind hole, so that the accurate positioning between the main shaft and the workpiece is realized, and then the clamping and fixing of the workpiece are realized by utilizing the three clamping columns which can independently rotate eccentrically, so that the accurate alignment between the processing position of the workpiece and the cutter can be realized on the premise of not changing the position of the cutter, and the whole clamp is simple to operate, stable in clamping and high in processing accuracy.

(2) Aiming at the negative suction positioning piece, the negative suction limiting is carried out by adopting a one-way exhaust mode, the structure is simple, and the operation is convenient.

(3) The negative suction positioning piece is correspondingly provided with the valve seat structure, and the valve seat structure can effectively change the one-way exhaust limitation, so that the negative suction positioning piece can be conveniently detached after the machining is finished.

(4) Aiming at the negative suction positioning piece, the calibration piece with a cross structure is correspondingly matched, so that the positioning between the negative suction positioning piece and the workpiece machining position can be more accurately realized.

(5) The negative suction positioning piece is correspondingly provided with a detachable limiting sleeve, the limiting sleeve is used for limiting the position of the piston plate on one hand, and the limiting sleeve is used for realizing the dismounting connection between the negative suction positioning piece and the marking piece on the other hand, so that the marking piece is conveniently dismounted between the connecting workpiece and the spindle.

Drawings

FIG. 1 is an exploded view of the structure of the present invention;

FIG. 2 is a schematic structural view of the negative suction positioning element of the present invention connected to a workpiece;

FIG. 3 is an enlarged view taken at A in FIG. 2;

FIG. 4 is a schematic structural view of the negative suction positioning element and the workpiece of the present invention when disassembled;

FIG. 5 is a perspective view of the negative attraction positioning element and the calibration element in the present invention;

FIG. 6 is a plan view of the negative suction positioning element, the calibration element and the workpiece of the present invention;

FIG. 7 is a schematic view of the clamping post of the present invention clamping a workpiece;

in the figure: a main shaft-1; positioning the blind hole-2; a negative suction positioning piece-3; a negative suction barrel-31; a piston plate-32; a threaded rod-33; a limiting spring-34; a one-way valve-35; a hollow valve seat-351; a connecting rod-352; seal sleeve-353; a porous filter plate-354; a positioning spring-355; a stop collar-36; a first seal ring-37; a second sealing ring-38; a clamping column-4; a rotary motor-41; a pressure sensor-42; a workpiece-5; a standard piece-6; a main calibration plate-61; a secondary calibration plate-62; a chute-63; an extension-64; a vertical plate-65.

Detailed Description

The technical solutions in the embodiments of the present invention will be clearly and completely described below with reference to the drawings in the embodiments of the present invention, and it is obvious that the described embodiments are only a part of the embodiments of the present invention, and not all of the embodiments. All other embodiments, which can be derived by a person skilled in the art from the embodiments given herein without making any creative effort, shall fall within the protection scope of the present invention.

Example one

Referring to fig. 1-2, in the present embodiment, a clamping fixture for a spindle of a machine tool is provided, and the clamping fixture includes:

the center of one end of the main shaft 1 is provided with a positioning blind hole 2, and the other end of the main shaft is connected with a machine tool;

the negative suction positioning piece 3 can be inserted into the positioning blind hole 2 in a matching way, and one end of the negative suction positioning piece 3 is connected with a workpiece 5 in a negative suction way;

evenly distributed in the three columniform clamp posts 4 of main shaft 1 one end, work piece 5 presss from both sides tightly between three clamp posts 4, and every clamp post 4 all forms independent eccentric rotation with main shaft 1 and is connected.

In particular, the negative suction positioning member 3 includes:

a negative suction barrel 31 with one open end, wherein the open end of the negative suction barrel 31 is contacted with the workpiece 5;

the piston plate 32 is slidably fitted inside the negative suction barrel 31, and a threaded rod 33 is fixed on the piston plate 32, and the threaded rod 33 penetrates through the other end of the negative suction barrel 31 (in this embodiment, the threaded rod 33 is screwed with the negative suction barrel 31).

With respect to the clamping post 4:

one end of each clamping column 4 is connected with a rotating motor 41, and the rotating motor 41 is embedded and fixed in the main shaft 1; a pressure sensor 42 is fixed to an outer wall of each of the clamping columns 4, and the rotary motor 41 stops the rotational drive in response to a detection value of the corresponding pressure sensor 42 exceeding a threshold value.

In summary, in this embodiment, the principle of accurately clamping the workpiece 5 on the spindle 1 is as follows:

taking a cylindrical workpiece 5 as an example in the figure, marking a position of the workpiece to be machined, then abutting an opening end of the negative suction barrel 31 against the marked position of the workpiece 5 (at this time, the piston plate 32 is located in an opening of the negative suction barrel 31), rotating the threaded rod 33 to realize spiral transmission between the threaded rod 33 and the negative suction barrel 31, thereby realizing the movement of the threaded rod 33 and the piston plate 32, and when the piston plate 32 is far away from the opening end of the negative suction barrel 31, forming negative pressure inside the negative suction barrel 31, thereby enabling the negative suction positioning member 3 to be fixed at the machining position of the workpiece 5 in a negative suction manner;

the negative suction positioning piece 3 which is fixedly connected with the workpiece 5 is inserted into the positioning blind hole 2, so that the machining position of the workpiece 5 and the axis of the spindle 1 form concentric fit (indicated by a dotted circle in fig. 7), then the rotating motor 41 is started, so that the three clamping columns 4 are driven to eccentrically rotate, along with the rotation of the clamping columns 4, the three clamping columns 4 gradually clamp the workpiece 5, the clamping force is detected through the pressure sensor 42 on the outer wall of the clamping columns 4, when the clamping force exceeds a threshold value, the rotating drive of the rotating motor 41 is stopped, and further the workpiece 5 is prevented from being deformed due to overlarge clamping force. Specifically, as can be seen from fig. 7, the left side in fig. 7 shows that the workpiece 5 is eccentrically machined by being clamped by the three clamp posts 4, and the right side in fig. 7 shows that the workpiece 5 is axially machined by being clamped by the three clamp posts 4.

Above-mentioned, in this embodiment, the operation of dismantling the negative suction positioning piece 3 after finishing the processing is: the threaded rod 33 is rotated in the reverse direction.

In addition, in the present embodiment, it is preferable that a first sealing ring 37 is sleeved on an opening end of the negative suction barrel 31, and the negative suction barrel 31 is in sealing contact with the workpiece 5 through the first sealing ring 37; a second sealing ring 38 is fixed to the piston plate 32, and the second sealing ring 38 is sealingly inserted into the interior of the first sealing ring 37. Thereby further improving the sealability when the negative suction bucket 31 is connected to the workpiece 5.

Example two

Referring to fig. 1 to 4, in the present embodiment, a clamping fixture for a spindle of a machine tool is provided, and the clamping fixture includes:

the center of one end of the main shaft 1 is provided with a positioning blind hole 2, and the other end of the main shaft is connected with a machine tool;

the negative suction positioning piece 3 can be inserted into the positioning blind hole 2 in a matching way, and one end of the negative suction positioning piece 3 is connected with a workpiece 5 in a negative suction way;

evenly distributed in the three columniform clamp posts 4 of main shaft 1 one end, work piece 5 presss from both sides tightly between three clamp posts 4, and every clamp post 4 all forms independent eccentric rotation with main shaft 1 and is connected.

In particular, the negative suction positioning member 3 includes:

a negative suction barrel 31 with one open end, wherein the open end of the negative suction barrel 31 is contacted with the workpiece 5;

the piston plate 32 is slidably fitted inside the negative suction barrel 31, and a threaded rod 33 is fixed on the piston plate 32, and the threaded rod 33 penetrates through the other end of the negative suction barrel 31 (in this embodiment, the threaded rod 33 is slidably fitted with the negative suction barrel 31).

Further, a limit spring 34 is connected between the piston plate 32 and the inner wall of the negative suction barrel 31, and the limit spring 34 is used for limiting the opening end of the piston plate 32 far away from the negative suction barrel 31; the first through hole is formed in the center of the threaded rod 33 and communicated with the opening of the negative suction barrel 31, the one-way valve 35 is arranged inside the first through hole, and the one-way valve 35 realizes one-way conduction of the negative suction barrel 31 to the direction of the threaded rod 33.

With respect to the clamping post 4:

one end of each clamping column 4 is connected with a rotating motor 41, and the rotating motor 41 is embedded and fixed in the main shaft 1; a pressure sensor 42 is fixed to an outer wall of each of the clamping columns 4, and the rotary motor 41 stops the rotational drive in response to a detection value of the corresponding pressure sensor 42 exceeding a threshold value.

In summary, in this embodiment, the principle of accurately clamping the workpiece 5 on the spindle 1 is as follows:

taking a cylindrical workpiece 5 as an example in the drawing, marking a position of the workpiece to be machined, then pressing an open end of the negative suction barrel 31 against the marked position of the workpiece 5 (at this time, based on the limitation of the limit spring 34, the piston plate 32 is located at a position farthest from the opening of the negative suction barrel 31), pushing the threaded rod 33, so that the piston plate 32 approaches to the open end of the negative suction barrel 31, and stretching the limit spring 34, during the process, based on the communication between the first through hole and the one-way valve 35, air inside the negative suction barrel 31 is effectively exhausted (in the direction shown by an arrow in fig. 3), and after the air is exhausted, the threaded rod 33 is loosened, so that the piston plate 32 is driven to be away from the open end of the negative suction barrel 31 under the resilience of the limit spring 34, so that negative pressure is formed inside the negative suction barrel 31, and the negative suction positioning element 3 is fixed at the machining position of the workpiece 5;

the negative suction positioning piece 3 which is fixedly connected with the workpiece 5 is inserted into the positioning blind hole 2, so that the machining position of the workpiece 5 and the axis of the spindle 1 form concentric fit (indicated by a dotted circle in fig. 7), then the rotating motor 41 is started, so that the three clamping columns 4 are driven to eccentrically rotate, along with the rotation of the clamping columns 4, the three clamping columns 4 gradually clamp the workpiece 5, the clamping force is detected through the pressure sensor 42 on the outer wall of the clamping columns 4, when the clamping force exceeds a threshold value, the rotating drive of the rotating motor 41 is stopped, and further the workpiece 5 is prevented from being deformed due to overlarge clamping force. Specifically, as can be seen from fig. 7, the left side in fig. 7 shows that the workpiece 5 is eccentrically machined by being clamped by the three clamp posts 4, and the right side in fig. 7 shows that the workpiece 5 is axially machined by being clamped by the three clamp posts 4.

In this embodiment, further:

a hollow valve seat 351 is fixed in the first through hole of the threaded rod 33, and the check valve 35 is installed inside the hollow valve seat 351;

a movable connecting rod 352 penetrates through the hollow valve seat 351, the connecting rod 352 is positioned at the outer side of the one-way valve 35, and a sealing sleeve 353 and a porous filter plate 354 are respectively fixed at two ends of the connecting rod 352 along the conduction direction of the one-way valve 35; the first through hole and the sealing sleeve 353 are sequentially communicated with the hollow valve seat 351, and a positioning spring 355 is connected between the porous filter plate 354 and the hollow valve seat 351;

a second through hole is formed in one side of the first through hole, and the positioning spring 355 is used for driving the sealing sleeve 353 to be close to the hollow valve seat 351 and sealing between the first through hole and the second through hole is achieved.

As can be seen from the above, in this embodiment, the operation of detaching the negative suction positioning element 3 after completing the processing is:

with the help of the push rod tool shown in fig. 4, the porous filter plate 354 is pushed to the hollow valve seat 351, and the sealing sleeve 353 is pushed through the connecting rod 352, so that the sealing sleeve 353 is far away from the hollow valve seat 351, and the dislocation of the sealing sleeve 353 and the second through hole is realized.

In addition, in the present embodiment, it is preferable that a first sealing ring 37 is sleeved on an opening end of the negative suction barrel 31, and the negative suction barrel 31 is in sealing contact with the workpiece 5 through the first sealing ring 37; a second sealing ring 38 is fixed to the piston plate 32, and the second sealing ring 38 is sealingly inserted into the interior of the first sealing ring 37. Thereby further improving the sealability when the negative suction bucket 31 is connected to the workpiece 5.

EXAMPLE III

The present embodiment is a further preferred embodiment of the first embodiment or the second embodiment, and in the present embodiment, the following preferred structures are included:

a cross-shaped structure of the calibration piece 6 cooperating with the negative suction positioning piece 3, and the calibration piece 6 comprises a main calibration plate 61 and three secondary calibration plates 62.

Specifically, the method comprises the following steps:

a limiting sleeve 36 is detachably screwed on the outer part of the threaded rod 33, and the limiting sleeve 36 is used for limiting the sliding position of the piston plate 32 in the negative suction barrel 31;

a sliding groove 63 is formed in the main calibration plate 61, the threaded rod 33 is in sliding fit with the sliding groove 63, and the diameter of the limiting sleeve 36 is larger than the width of the sliding groove 63;

a transparent scale is provided in the middle of the sub-calibration plate 62.

In summary, the accurate matching principle of the negative suction positioning piece 3 and the workpiece 5 is realized as follows:

taking fig. 5 as an example: the threaded rod 33 is inserted into the sliding groove 63 from bottom to top, and then the limiting sleeve 36 is screwed and connected to the threaded rod 33 from top to bottom, so that the negative suction positioning piece 3 is connected with the marking piece 6;

referring to fig. 6, the calibration piece 6 is tightly attached to one end of the workpiece 5, and the transparent scales on the three secondary calibration plates 62 are used for marking and positioning the three edges of the workpiece 5, so as to ensure that the center of the calibration piece 6 is coincident with the center of the workpiece 5; then, the negative suction positioning piece 3 is moved along the sliding groove 63, so that the negative suction positioning piece 3 is moved to a position where the workpiece 5 needs to be processed, the limiting sleeve 36 is rotated, the detachment of the limiting sleeve 36 and the marking piece 6 is completed, and the negative suction connection between the negative suction positioning piece 3 and the workpiece 5 is completed according to the principle of the first embodiment or the second embodiment.

Further, three extending portions 64 are formed at one end of the main calibration plate 61, and three vertical plates 65 are connected between the three extending portions 64 and the three sub calibration plates 62 in a one-to-one correspondence manner.

Based on this:

ensuring that the three auxiliary calibration plates 62 are tightly attached to the workpiece 5, thereby improving the accuracy of positioning the transparent scale and the edge of the workpiece 5;

a moving channel capable of accommodating the negative suction barrel 31 is formed between the main calibration plate 61 and the workpiece 5, so that the movement and positioning of the negative suction barrel 31 and the workpiece 5 are conveniently realized.

Although embodiments of the present invention have been shown and described, it will be appreciated by those skilled in the art that changes, modifications, substitutions and alterations can be made in these embodiments without departing from the principles and spirit of the invention, the scope of which is defined in the appended claims and their equivalents.