CN219609332U

CN219609332U - Automatic polarized light source adjusting mechanism

Info

Publication number: CN219609332U
Application number: CN202320993716.0U
Authority: CN
Inventors: 朱利军
Original assignee: Suzhou Omite Optoelectronic Technology Co ltd
Current assignee: Suzhou Omite Optoelectronic Technology Co ltd
Priority date: 2023-04-27
Filing date: 2023-04-27
Publication date: 2023-08-29
Anticipated expiration: 2033-04-27

Abstract

The utility model discloses an automatic polarized light source adjusting mechanism, which belongs to the field of microscopes and comprises a microscope body, wherein the microscope body comprises a base and a vertical plate fixedly arranged at the top end of the base, a light supplementing lamp is fixedly arranged at the top end of the base, a mounting plate is rotatably arranged at the front side of the vertical plate, supporting blocks are fixedly arranged at both sides of the mounting plate, a placing ring is fixedly arranged between the two supporting blocks, a polarizer is arranged in the placing ring, a mounting groove is formed in the vertical plate, a supporting block is slidably arranged in the mounting groove, one end of the supporting block penetrates through the mounting groove and is fixedly provided with a supporting plate, and the center of the supporting plate, the placing ring and the center of the light supplementing lamp are positioned on the same vertical center line. According to the utility model, the polarizer angle adjusting function is achieved through the arrangement of the adjusting component, so that the light source angle adjusting function is achieved, and the polarizer stabilizing function is achieved through the arrangement of the supporting component, so that the stability of polarizer adjustment is improved.

Description

Automatic polarized light source adjusting mechanism

Technical Field

The utility model relates to the field of microscopes, in particular to an automatic polarized light source adjusting mechanism.

Background

The metallographic microscope or the digital metallographic microscope is a high-tech product developed and developed by perfectly combining an optical microscope technology, a photoelectric conversion technology and a computer image processing technology, and metallographic images can be conveniently observed on a computer, so that metallographic images are analyzed, rated and the like, pictures are output and printed, the angle of a light source of the microscope needs to be adjusted in the using process, and workers can conveniently check the condition of a broken piece carrying sample.

The utility model discloses a polarizing microscope's automatic polarizing device is disclosed to patent application number 202221400485.X, including the microscope body, microscope body front side is provided with horizontal layer board, and has seted up the through-hole that link up from top to bottom on the layer board lateral wall, is equipped with the elevating system who promotes its height between layer board and the microscope body, rotates on the microscope body front end lateral wall and is connected with the mounting panel, and the mounting panel transversely sets up in the downside of layer board, and the inboard installation of mounting panel is provided with the polarizer, and microscope body upside is equipped with the adjustment mechanism who is used for adjusting the polarizer. This application can change its whole angle to mounting panel application of force, and then changes the polarisation angle of polariscope for sample observation in-process has richer polarisation condition, thereby obtains more comprehensive sample observation result, and can change the height of layer board and sample in the observation process, adjusts the interval between sample and the objective, changes the focus and satisfies the different observations to the sample.

To foretell correlation technique, utilize screw thread and screw sleeve spiro union cooperation through twisting the ejector pin that sets up, make the ejector pin remove along screw sleeve ascending side, with this changes its whole angle to mounting panel application of force, and then change the polarisation angle of polarizer, make the sample observation in-process have richer polarisation condition, thereby obtain more comprehensive sample observation result, but need the staff both hands to rotate two ejector pins simultaneously, a forward rotation, another counter-rotating just does not influence the mounting panel rotation, and mounting panel angle modulation is accomplished and is contradicted firmly through the ejector pin, place the board and probably produce under reset coil spring's elasticity effect and rock, can make the light source rock, inconvenient staff follow-up observation sample.

Disclosure of Invention

In order to solve the problems, the utility model provides an automatic polarized light source adjusting mechanism, which adopts the following technical scheme:

the utility model provides a polarized light source automatic adjustment mechanism, includes the microscope body, the microscope body includes base and fixed mounting in the riser on base top, base top fixed mounting has the light filling lamp, riser front side rotates installs the mounting panel, just the mounting panel both sides are all fixed mounting has a piece, two fixed mounting has the ring of placing between the piece, just be equipped with the polarizer in the ring of placing, the mounting groove has been seted up to the riser, just install the supporting shoe in the mounting groove sliding, supporting shoe one end runs through the mounting groove and fixed mounting has the layer board, just layer board, place ring and light filling lamp centre of a circle are located same vertical central line, riser one side is equipped with control button, supporting shoe keeps away from layer board one end and is equipped with lifting assembly; the base top end fixed mounting has two be the symmetric distribution pillar, and two the pillar top with be equipped with supporting component between the same group prop up the piece bottom, base top slidable mounting has two installation boxes that are symmetric distribution, and two all be equipped with adjusting part in the installation box.

Through adopting above-mentioned technical scheme, when this equipment was used, the staff placed the polarizer in and placed in the ring, afterwards, the staff helped the layer board surface with the slide glass, afterwards, can observe the sample condition, staff accessible control button drive lifting unit moves, make supporting shoe take layer board and slide glass to go up and down simultaneously, reach the effect of adjusting the distance between carrying broken piece and the objective, can play the effect of adjusting the focus, be convenient for the staff follow-up observation, when needing to adjust the light source, the staff is with one of them installation box slip place behind the homonymy piece, rise through adjusting unit drive homonymy piece, and then to place ring and polarizer rotation, can reach the effect of adjusting the light source, when need to adjust the light source to the opposite side, the staff is with another group adjusting unit slip place homonymy piece below, repeat above-mentioned operation can, and wherein a set of adjusting unit breaks away from with homonymy piece, when placing ring and polarizer and take place the rotation, prop up the setting of piece below through supporting unit, play the effect of supporting firm ring of placing, be favorable to keeping the stability of polarizer rotation, and then be favorable to keeping the stability of light source.

Further, the lifting assembly comprises a gear motor fixedly mounted on the inner wall of the bottom end of the mounting groove, a first screw is fixedly mounted at the end part of the output shaft of the gear motor, the top end of the first screw is rotationally connected with the inner wall of the top end of the mounting groove, the supporting block is far away from one end of the supporting plate, the side wall of the first screw is sleeved with a thread, and a baffle ring is fixedly sleeved on the side wall of the lower section of the first screw.

Through adopting above-mentioned technical scheme, through control button drive gear motor operation, gear motor drive first screw rod rotates, makes the supporting shoe be located first screw rod lateral wall and goes up and down, and the supporting shoe is carried layer board and is carried the piece and goes up and down in step, reaches the effect of adjusting the distance between piece and the objective that carries.

Further, the support block both sides are all fixed mounting has firm piece, riser is close to layer board one side offered with support block assorted export, just export link up the mounting groove, export inboard offered with homonymy firm piece assorted firm groove.

Through adopting above-mentioned technical scheme, when the supporting shoe goes up and down, the supporting shoe is located homonymy firm inslot and slides with firm piece, through firm piece and firm groove's cooperation, is favorable to improving the stability that the supporting shoe goes up and down, is favorable to avoiding carrying the rupture disc and producing the skew when going up and down.

Further, the supporting component comprises a supporting rod which is slidably arranged in a supporting column, movable grooves matched with the supporting rod in the same group are formed in the top end of the supporting column, supporting springs are connected between the bottom ends of the supporting rod and the inner walls of the bottom ends of the movable grooves in the same group, and the top ends of the supporting rod are contacted with the bottom ends of the supporting blocks in the same group.

Through adopting above-mentioned technical scheme, when placing the ring and taking place the skew, descend the piece to promote with side branch to slide in the same group's movable groove, and make same group's supporting spring shrink, branch promotes with group's piece under supporting spring's reverse promotion, plays the effect that supports firmly placing the ring, and another branch rises under the elasticity effect with group's supporting spring, plays the effect of firmly placing the ring opposite side.

Further, adjusting part includes fixed mounting in the locating lever of installation box bottom inner wall, locating lever lateral wall rotation cover is equipped with the support column, and same group locating lever and support column top all run through same group the installation box, the second helicoidal groove has all been seted up on the support column top, just all be equipped with the second screw rod in the second helicoidal groove, the second screw rod inside seted up with same group locating lever assorted constant head tank, just the locating lever upper segment is the quadrangular, the equal fixed cover of support column hypomere lateral wall is equipped with driven gear, two the dead lever is installed in the equal rotation of one side opposite to the installation box, and two the dead lever keeps away from homonymy installation box one side fixed mounting has the handle, two the opposite one end of dead lever all runs through same group the installation box, and two the dead lever runs through the equal fixed cover of installation box one end lateral wall is equipped with drive gear, drive gear with same group driven gear meshing.

Through adopting above-mentioned technical scheme, through the rotation of handle dwang, dwang drive gear rotates, and drive gear drive driven gear rotates, and driven gear drive support column rotates, makes the second screw rod go up and down, and runs through to in the second screw rod through the locating lever slip, plays the effect that restricts second screw rod along with support column synchronous rotation, is favorable to keeping the stable lift of second screw rod, promotes with group's piece through the second screw rod and risees, makes to place ring and polarizer to the opposite side rotation, can play the effect of adjusting the light source angle.

Further, two equal fixed mounting of installation box bottom has the slider, the spout with slider assorted is seted up on the base top, and two equal fixed mounting has the slide bar in the spout, two the slider slip cap is located same group the slide bar lateral wall.

Through adopting above-mentioned technical scheme, the installation box bottom is through the setting of slider, is located the inslot that sideslips through the slider and slides, and the slide bar lateral wall is located to slider sliding sleeve, is favorable to improving the gliding stability of installation box.

Further, the side wall of the placing ring is provided with a fastening bolt, the side wall of the placing ring is provided with a fastening screw hole matched with the fastening bolt, and the inner wall of the placing ring is fixedly provided with a rubber pad.

Through adopting above-mentioned technical scheme, after the staff places the polarizer in the ring inside of placing, the staff places fastening bolt in the fastening helicoid, supports the polarizer lateral wall through fastening bolt tip, can play the effect of fixed polarizer, and places the ring inboard and pass through the setting of rubber pad, can play the effect of protection polarizer.

In summary, the utility model has the following beneficial technical effects:

(1) According to the utility model, through the arrangement of the adjusting components, the sliding mounting box for the staff is arranged below the same side supporting block, then, the rotating rod is rotated by the handle to drive the supporting column to rotate, so that the second thread is lifted to be in contact with the bottom of the same side supporting block, the same side supporting block is pushed by the second screw to be continuously lifted, the effect of driving the placing ring and the polarizer to rotate is achieved, the effect of adjusting the angle of the light source is achieved, the angle of the polarizer is conveniently adjusted by the staff through the cooperation of the two groups of adjusting components, the effect of supporting and stabilizing the placing ring is achieved through the arrangement of the supporting components, the stability of the offset of the placing ring is guaranteed, the effect of keeping the stability of the polarizer is achieved, and the staff can conveniently check objects required to be observed later.

(2) According to the utility model, the lifting assembly is arranged to play a role in adjusting the heights of the supporting plate and the sample, so that the distance between the sample and the objective lens is changed, the effect of adjusting the focal length is achieved, and the follow-up observation of staff is facilitated.

Drawings

FIG. 1 is a schematic diagram of an automatic polarized light source adjusting mechanism;

FIG. 2 is an enlarged view of FIG. 1A in accordance with the present utility model;

FIG. 3 is a cross-sectional view of the present utility model;

FIG. 4 is an enlarged view of B of FIG. 3 in accordance with the present utility model;

FIG. 5 is an enlarged view of C of FIG. 3 in accordance with the present utility model;

fig. 6 is an exploded view of the adjustment assembly of the present utility model.

The reference numerals in the figures illustrate:

1. a microscope body; 2. a chute; 3. a slide block; 4. a mounting box; 5. placing a ring; 6. a polarizer; 7. a support block; 8. a supporting plate; 9. a support block; 10. a first screw; 11. a mounting plate; 12. a support rod; 13. a support post; 14. a support column; 15. a light supplementing lamp; 16. a fastening bolt; 17. a second screw; 18. a mounting groove; 19. a speed reducing motor; 20. a positioning rod; 21. a drive gear; 22. a rotating lever; 23. a driven gear; 24. a movable groove; 25. and a support spring.

Detailed Description

The technical solutions in the embodiments of the present utility model will be clearly and completely described below with reference to the accompanying drawings in the embodiments of the present utility model; it is apparent that the described embodiments are only some embodiments of the present utility model, not all embodiments, and that all other embodiments obtained by persons of ordinary skill in the art without making creative efforts based on the embodiments in the present utility model are within the protection scope of the present utility model.

In the description of the present utility model, it should be noted that the positional or positional relationship indicated by the terms such as "upper", "lower", "inner", "outer", "top/bottom", etc. are based on the positional or positional relationship shown in the drawings, are merely for convenience of describing the present utility model and simplifying the description, and do not indicate or imply that the apparatus or elements referred to must have a specific orientation, be constructed and operated in a specific orientation, and thus should not be construed as limiting the present utility model. Furthermore, the terms "first," "second," and the like, are used for descriptive purposes only and are not to be construed as indicating or implying relative importance.

In the description of the present utility model, it should be noted that, unless explicitly specified and limited otherwise, the terms "mounted," "configured to," "engaged with," "connected to," and the like are to be construed broadly, and may be either fixedly connected, detachably connected, or integrally connected, for example; can be mechanically or electrically connected; can be directly connected or indirectly connected through an intermediate medium, and can be communication between two elements. The specific meaning of the above terms in the present utility model will be understood in specific cases by those of ordinary skill in the art.

The utility model is described in further detail below with reference to fig. 1-6.

Referring to fig. 1-6, an automatic polarized light source adjusting mechanism comprises a microscope body 1, the microscope body 1 comprises a base and a vertical plate fixedly mounted at the top end of the base, a light supplementing lamp 15 is fixedly mounted at the top end of the base, a mounting plate 11 is rotatably mounted at the front side of the vertical plate, supporting blocks 7 are fixedly mounted at two sides of the mounting plate 11, a placing ring 5 is fixedly mounted between the two supporting blocks 7, a polarizer 6 is arranged in the placing ring 5, a mounting groove 18 is formed in the vertical plate, a supporting block 9 is slidably mounted in the mounting groove 18, one end of the supporting block 9 penetrates through the mounting groove 18 and is fixedly mounted with a supporting plate 8, the centers of the supporting plate 8, the placing ring 5 and the light supplementing lamp 15 are located at the same vertical center line, a fastening bolt 16 is arranged on the side wall of the placing ring 5, a fastening screw hole matched with the fastening bolt 16 is formed in the side wall of the placing ring 5, a rubber pad is fixedly mounted on the inner wall of the placing ring 5, when the device is used, a worker places the polarizer 6 in the placing ring 5, the polarizer 6 in the fastening screw groove, the fastening screw groove 16 is formed in the side wall, the fastening screw 16 is fixedly mounted on the side wall by the worker, the side wall is fixedly mounted on the supporting plate 6 through the side wall 6, the supporting plate 8 through the supporting plate, the supporting ring 8 can be placed against the side 6, and can play a role of protecting the side of the worker, and can play a role of protecting the side of the side by the worker.

The riser one side is equipped with control button, supporting shoe 9 keeps away from layer board 8 one end and is equipped with lifting unit, lifting unit includes fixed mounting in gear motor 19 of mounting groove 18 bottom inner wall, gear motor 19 output shaft end fixed mounting has first screw rod 10, and first screw rod 10 top and mounting groove 18 top inner wall rotate and be connected, supporting shoe 9 keeps away from layer board 8 one end thread bush and locates first screw rod 10 lateral wall, first screw rod 10 hypomere lateral wall fixed cover is equipped with the baffle ring, through control button drive gear motor 19 operation, gear motor 19 drive first screw rod 10 rotates, make supporting shoe 9 be located first screw rod 10 lateral wall lift, supporting shoe 9 carries layer board 8 and year broken piece synchronous lifting, reach the effect of adjusting the distance between broken piece and the objective, satisfy the different demand observation to the sample.

The equal fixed mounting in supporting shoe 9 both sides has firm piece, and the riser is close to supporting plate 8 one side and has offered the export with supporting shoe 9 assorted, and export link up mounting groove 18, and export inboard offered with homonymy firm piece assorted firm groove, when supporting shoe 9 goes up and down, supporting shoe 9 is located homonymy firm inslot and slides with firm piece, through the cooperation in firm piece and firm groove, is favorable to improving the stability that supporting shoe 9 goes up and down, is favorable to avoiding carrying the broken piece and produces the skew when going up and down.

The base top slidable mounting has two mounting boxes 4 that are symmetrical distribution, and all be equipped with adjusting part in two mounting boxes 4, adjusting part includes fixed mounting in the locating lever 20 of mounting box 4 bottom inner wall, locating lever 20 lateral wall rotation cover is equipped with support column 14, and with group locating lever 20 and support column 14 top all run through with group mounting box 4, the second helicoidal groove has all been seted up on support column 14 top, and all be equipped with second screw rod 17 in the second helicoidal groove, second screw rod 17 inside seted up with same group locating lever 20 assorted constant head tank, and the locating lever 20 upper segment is the quadrangular, support column 14 hypomere lateral wall all fixed sleeve is equipped with driven gear 23, the opposite side of two mounting boxes 4 is all rotated and is installed dwang 22, and two dwang 22 keep away from same side mounting box 4 one side fixed mounting and have the handle, the opposite one end of two dwang 22 all runs through same group mounting box 4, and two dwang 22 run through the equal fixed sleeve of mounting box 4 one end lateral wall and are equipped with driving gear 21, driving gear 21 and same group driven gear 23 mesh, through handle dwang 22 rotation, the inside is equipped with driven gear 21, drive gear 21 with same group driven gear 23, drive 17 rotation along with second screw rod 17 rotation, the same side is equipped with driven gear 17 rotation, the second side drive gear 17 rotation of drive gear 17, the second side is equipped with driven gear 17 rotation, the second side is along with 17 rotation, the second side is favorable to rotate the second screw rod 17, the side is rotated to rotate, the side is rotated to be equipped with the light source 17, and the second side is rotated, the side is rotated, and is rotated to be placed to the side, and is rotated, the side is rotated, and is 17, the side is rotated.

Two installation box 4 bottom equal fixed mounting have slider 3, and the spout 2 with slider 3 assorted has been seted up on the base top, and equal fixed mounting has the slide bar in two spouts 2, and two slider 3 slip cap locate with group's slide bar lateral wall, and installation box 4 bottom is located with the side spout 2 through slider 3 and slides, and slider 3 slip cap locates the slide bar lateral wall, is favorable to improving the gliding stability of installation box 4.

The base top end fixed mounting has two and is symmetrical distribution pillar 13, and be equipped with supporting component between two pillar 13 tops and the same group of supporting shoe 7 bottom, supporting component includes slidable mounting in the branch 12 in pillar 13, two pillar 13 tops offer with same group of branch 12 assorted movable slot 24, and all be connected with supporting spring 25 between two branch 12 bottoms and the same group of movable slot 24 bottom inner wall, two branch 12 tops and same group of supporting shoe 7 bottom contact, when placing ring 5 and taking place the skew, decline supporting shoe 7 promotes homonymy branch 12 to same group of movable slot 24 internal sliding, and make same group of supporting spring 25 shrink, branch 12 promotes same group of supporting shoe 7 under the reverse promotion of supporting spring 25, play the effect of supporting firmly place ring 5, and another branch 12 rises under the elasticity effect of same group of supporting spring 25, play the effect of firmly placing the ring 5 opposite side.

The implementation principle of the embodiment of the utility model is as follows: when the device is used, a worker places the polarizer 6 in the placement ring 5, then, the worker helps the glass slide to the surface of the supporting plate 8, then, the sample condition can be observed, the worker can drive the lifting assembly to operate through the control button, the supporting block 9 is enabled to lift simultaneously with the supporting plate 8 and the glass slide, the function of adjusting the distance between the carrying broken piece and the objective lens is achieved, the function of adjusting the focal length can be achieved, the follow-up observation of the worker is facilitated, when the light source needs to be adjusted, the worker slides one of the mounting boxes 4 below the same side supporting block 7, the worker drives the same side supporting block 7 to lift through the adjusting assembly, then the placement ring 5 and the polarizer 6 rotate, the effect of adjusting the light source can be achieved, when the light source needs to be adjusted to the other side, the worker slides the other group of adjusting assembly below the same side supporting block 7, the operation can be repeated, one group of adjusting assemblies is separated from the same side supporting block 7, the placement ring 5 and the polarizer 6 rotate, the supporting block 7 is enabled to be arranged through the supporting assembly, the function of supporting the supporting assembly, the placement ring 5 is facilitated, the stability of the light source is maintained, and the stability of the light source is further maintained.

The above embodiments are not intended to limit the scope of the present utility model, so: all equivalent changes in structure, shape and principle of the utility model should be covered in the scope of protection of the utility model.

Claims

1. The utility model provides a polarized light source automatic adjustment mechanism, includes microscope body (1), its characterized in that: the microscope body (1) comprises a base and a vertical plate fixedly mounted on the top end of the base, a light supplementing lamp (15) is fixedly mounted at the top end of the base, a mounting plate (11) is rotatably mounted on the front side of the vertical plate, supporting blocks (7) are fixedly mounted on two sides of the mounting plate (11), a placing ring (5) is fixedly mounted between the supporting blocks (7), a polarizer (6) is arranged in the placing ring (5), a mounting groove (18) is formed in the vertical plate, a supporting block (9) is mounted in the mounting groove (18) in a sliding mode, one end of the supporting block (9) penetrates through the mounting groove (18) and is fixedly mounted with a supporting plate (8), the centers of the supporting plate (8), the placing ring (5) and the light supplementing lamp (15) are located on the same vertical center line, a control button is arranged on one side of the vertical plate, and a lifting assembly is arranged at one end, far away from the supporting block (9); the base top end fixed mounting has two be symmetric distribution pillar (13), and two pillar (13) top with be equipped with supporting component between the group in prop up piece (7) bottom, base top slidable mounting has two mounting boxes (4) that are symmetric distribution, and two all be equipped with adjusting part in mounting box (4).

2. The polarized light source automatic adjusting mechanism according to claim 1, wherein: the lifting assembly comprises a gear motor (19) fixedly mounted on the inner wall of the bottom end of the mounting groove (18), a first screw (10) is fixedly mounted at the end part of an output shaft of the gear motor (19), the top end of the first screw (10) is rotationally connected with the inner wall of the top end of the mounting groove (18), the supporting block (9) is far away from one end of the supporting plate (8) and is sleeved on the side wall of the first screw (10), and a baffle ring is fixedly sleeved on the side wall of the lower section of the first screw (10).

3. The polarized light source automatic adjusting mechanism according to claim 1, wherein: the utility model discloses a support block, including supporting plate (8), supporting plate (9) both sides all fixed mounting have firm piece, the riser is close to supporting plate (8) one side offered with supporting plate (9) assorted export, just export link up mounting groove (18), export inboard offered with homonymy firm piece assorted firm groove.

4. The polarized light source automatic adjusting mechanism according to claim 1, wherein: the support assembly comprises support rods (12) which are slidably mounted in support rods (13), movable grooves (24) matched with the support rods (12) are formed in the top ends of the support rods (13), support springs (25) are connected between the bottom ends of the support rods (12) and the inner walls of the bottom ends of the movable grooves (24), and the top ends of the support rods (12) are in contact with the bottom ends of the support blocks (7).

5. The polarized light source automatic adjusting mechanism according to claim 1, wherein: the utility model provides a drive gear (21) is equipped with driven gear (23) with fixed cover, and two in the same group is equipped with in locating lever (20) lateral wall rotation cover in installation box (4) bottom inner wall, and with group locating lever (20) and support column (14) top all run through with group installation box (4), the second spiral shell groove has all been seted up on support column (14) top, just all be equipped with second screw rod (17) in the second spiral shell inslot, second screw rod (17) inside set up with same group locating lever (20) assorted constant head tank, just locating lever (20) upper segment is quadrangular, support column (14) lower segment lateral wall all fixed cover is equipped with driven gear (23), two one side opposite to installation box (4) is all rotated and is installed dwang (22), and two dwang (22) keep away from the same side installation box (4) one side fixed mounting has the handle, two one end opposite to dwang (22) all runs through same group installation box (4), and two dwang (21) one end opposite to run through same group drive gear (21) and drive gear (21) all meshes with driven gear (21).

6. The polarized light source automatic adjusting mechanism according to claim 1, wherein: two equal fixed mounting of mounting box (4) bottom has slider (3), base top seted up with slider (3) assorted spout (2), and two equal fixed mounting has the slide bar in spout (2), two slider (3) slip cap is located same group the slide bar lateral wall.

7. The polarized light source automatic adjusting mechanism according to claim 1, wherein: the side wall of the placing ring (5) is provided with a fastening bolt (16), the side wall of the placing ring (5) is provided with a fastening screw hole matched with the fastening bolt (16), and the inner wall of the placing ring (5) is fixedly provided with a rubber pad.