CN220388770U - Clamping and feeding device for mechanical material transmission - Google Patents

Abstract

The utility model discloses a clamping and feeding device for mechanical material transmission, relates to the technical field of conveying devices, and particularly relates to a mechanical hand clamping and feeding device for material transmission. The utility model comprises the following steps: the mechanical arm clamping mechanism, the rotating mechanism and the receiving mechanism; the front end of the mechanical arm is connected with a clamping mechanism for clamping materials; the material receiving mechanism is rotationally connected with the clamping mechanism through the rotating mechanism, so that the material is prevented from falling. The technical scheme of the utility model solves the problems that the existing mechanical hand in the prior art has insufficient clamping effect and is easy to fall down to cause larger loss when clamping cylindrical, elliptic and other smooth-surface materials.

Description

Clamping and feeding device for mechanical material transmission

Technical Field

The utility model discloses a clamping and feeding device for mechanical material transmission, relates to the technical field of conveying devices, and particularly relates to a mechanical hand clamping and feeding device for material transmission.

Background

The feeding refers to automatic processing of materials in a machine, but with the development of society, the produced materials are gradually increased, but the manual feeding efficiency is too low, so that the production needs cannot be met, and in order to improve the production efficiency, most factories adopt mechanical arm automatic feeding devices.

The existing automatic feeding device for the mechanical arm comprises a mechanical arm control circuit, a mechanical arm and a clamping assembly, wherein the control circuit controls the mechanical arm to move to change the position of the clamping mechanism, so that automatic feeding is realized.

Although the prior art can effectively provide a reliable fixing effect for materials in the material transferring and feeding process through the clamping mechanism, certain defects still exist in the actual use process, for example, when the clamping mechanism on the mechanical arm clamps cylindrical and oval material with smooth surfaces, the clamping mechanism always has the phenomenon of insufficient clamping effect on the material, the material is easy to fall down in the transferring process, and larger damage is generated.

Aiming at the problems in the prior art, a novel clamping feeding device for mechanical material transmission is researched and designed, so that the problems in the prior art are overcome.

Disclosure of Invention

According to the prior art, the clamping and feeding device for mechanical material transmission has the technical problems that the clamping effect is insufficient, the mechanical hand is easy to fall down and large loss is caused when the mechanical hand clamps cylindrical, elliptic and other smooth-surface materials. According to the utility model, the material receiving mechanism capable of automatically avoiding and receiving is arranged below the clamping mechanism, so that the clamped materials are received in a protective way, and the purpose of preventing the materials from falling down and causing loss is achieved.

The utility model adopts the following technical means:

a centre gripping loading attachment for mechanical material transmission includes: the mechanical arm clamping mechanism, the rotating mechanism and the receiving mechanism;

further, the front end of the mechanical arm is connected with a clamping mechanism for clamping materials;

further, the material receiving mechanism is rotationally connected with the clamping mechanism through the rotating mechanism, so that the material is prevented from falling.

Further, the clamping mechanism includes: clamping the moving plate, clamping the plate, driving the trough, reversing the threaded rod, driving the threaded sleeve and driving the motor;

further, the upper end of the clamping moving plate is hinged with the output end of the mechanical arm;

further, a driving groove is formed in the bottom surface of the clamping moving plate;

further, the reverse threaded rod is arranged in the driving groove, and two ends of the reverse threaded rod are arranged at two ends of the driving groove through bearing seats;

further, two transmission threaded sleeves are symmetrically arranged on the rod body of the reverse threaded rod;

further, the lower parts of the two transmission screw sleeves are respectively provided with a clamping plate, the clamping plates are telescopic grooves with hollow structures, and rotating mechanisms are arranged in the telescopic grooves;

further, the driving motor is arranged at one end of the clamping moving plate, and the output end of the driving motor penetrates through the clamping moving plate and is fixedly connected with one end of the reverse threaded rod.

Further, the rotation mechanism includes: the device comprises a transmission gear, a rotating rod, a transmission toothed plate, an extrusion plate, a compression spring and a rotation supply groove;

further, the top end of the transmission toothed plate is fixedly connected with the extrusion plate and is arranged in the telescopic groove of the clamping plate together;

further, a compression spring is arranged between the extrusion plate and the inner top wall of the telescopic groove;

further, the transmission toothed plate is meshed with a transmission gear arranged at the lower part of the extrusion plate;

further, the rotating rod vertically penetrates into the telescopic groove, the upper end of the rotating rod is fixedly connected with the central shaft of the transmission gear, and the lower end of the rotating rod is connected with the material receiving mechanism;

further, the rotating rod is driven by the transmission toothed plate to rotate, and the rotating rod enters a rotation supplying groove arranged on the surface of the clamping plate in the rotation process and used for rotating the rotating rod.

Further, a limited rail sliding strip is arranged on the side edge of the transmission toothed plate;

further, a rail limiting sliding groove matched with the rail limiting sliding strip is arranged on the inner wall of the telescopic groove;

further, the rail limiting sliding strip and the rail limiting sliding groove are matched for use, so that the movement of the transmission toothed plate is guided.

Further, the transmission toothed plate is located outside the lower end of the clamping plate and is longer than 1/4 arc length of the transmission gear, so that the transmission toothed plate can drive the rotating rod to rotate by 90 degrees through the clamping plate.

Further, the receiving mechanism includes: a shrinkage sleeve and a telescopic plate;

further, one end of the shrinkage sleeve is fixedly connected with the bottom end of a rotating rod;

further, one end of the expansion plate is fixedly connected with the bottom end of the other rotating rod;

further, the free end of the telescopic sleeve is slidably arranged on the free end of the telescopic plate, so that the telescopic sleeve forms an extensible and contractible bearing structure.

Further, magnet plates are embedded on the top surfaces of the shrinkage sleeve and the expansion plate.

Further, two baffle plates A are respectively arranged on two side edges of the top surface of the shrinkage sleeve;

further, two baffle plates B are respectively arranged on two side edges of the top surface of the expansion plate;

further, a sliding seam matched with the baffle B is also arranged on the top surface of the shrinkage sleeve.

Compared with the prior art, the utility model has the following advantages:

according to the clamping feeding device for mechanical material transmission, through the arrangement of the receiving mechanism, when the mechanical arm drives the clamping mechanism to do descending motion, the rotation supplying part in the receiving mechanism can be firstly contacted with a table surface for placing materials and feel the pressure of the table surface, and the rotation force is provided for the telescopic receiving part so as to drive the telescopic receiving part to rapidly overturn ninety degrees, so that the clamping moving plate can be conveniently positioned between two clamping plates in the further descending process, the clamping mechanism is conveniently used for driving the clamping plates to clamp the materials, otherwise, after the clamping plate is used for clamping the materials, the rotation supplying part can rapidly reversely drive the telescopic receiving part to reversely overturn to a horizontal position when the clamping moving plate moves upwards, a material receiving platform can be effectively formed below the materials, and even if the materials fall off from the two clamping plates, the telescopic receiving part can still well receive the materials, so that the materials can be prevented from falling to the ground directly to cause damage.

In conclusion, the technical scheme of the utility model solves the problems that the existing manipulator in the prior art has insufficient clamping effect and is easy to fall down to cause larger loss when clamping cylindrical, elliptic and other smooth-surface materials.

Drawings

In order to more clearly illustrate the embodiments of the present utility model or the technical solutions in the prior art, the drawings that are required in the embodiments or the description of the prior art will be briefly described, and it is obvious that the drawings in the following description are some embodiments of the present utility model, and other drawings may be obtained according to the drawings without inventive effort to a person skilled in the art.

Fig. 1 is a schematic diagram of the overall structure of the present utility model.

Fig. 2 is a schematic structural view of a clamping mechanism and a receiving mechanism in the present utility model.

Fig. 3 is an enlarged schematic view of fig. 2 a in accordance with the present utility model.

Fig. 4 is a schematic view of the structure of the driving toothed plate and the clamping plate of the present utility model.

In the figure: 1. the mechanical arm 2, the clamping moving plate 3, the clamping plate 4, the driving groove 5, the reverse threaded rod 6, the transmission threaded sleeve 7, the driving motor 8, the shrinkage sleeve 9, the expansion plate 10, the expansion groove 11, the transmission gear 12, the rotating rod 13, the transmission toothed plate 14, the extrusion plate 15, the compression spring 16, the rotation groove 17, the rail limiting slide bar 18, the rail limiting slide groove 19, the baffle A20, the baffle B21 and the slide slot.

Detailed Description

It should be noted that, without conflict, the embodiments of the present utility model and features of the embodiments may be combined with each other. The utility model will be described in detail below with reference to the drawings in connection with embodiments.

For the purpose of making the objects, technical solutions and advantages of the embodiments of the present utility model more apparent, the technical solutions of 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, and it is apparent that the described embodiments are only some embodiments of the present utility model, not all embodiments. The following description of at least one exemplary embodiment is merely exemplary in nature and is in no way intended to limit the utility model, its application, or uses. All other embodiments, which can be made by those skilled in the art based on the embodiments of the utility model without making any inventive effort, are intended to be within the scope of the utility model.

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

The relative arrangement of the components and steps, numerical expressions and numerical values set forth in these embodiments do not limit the scope of the present utility model unless it is specifically stated otherwise. Meanwhile, it should be clear that the dimensions of the respective parts shown in the drawings are not drawn in actual scale for convenience of description. Techniques, methods, and apparatus known to those of ordinary skill in the relevant art may not be discussed in detail, but are intended to be part of the specification where appropriate. In all examples shown and discussed herein, any specific values should be construed as merely illustrative, and not a limitation. Thus, other examples of the exemplary embodiments may have different values. It should be noted that: like reference numerals and letters denote like items in the following figures, and thus once an item is defined in one figure, no further discussion thereof is necessary in subsequent figures.

In the description of the present utility model, it should be understood that the azimuth or positional relationships indicated by the azimuth terms such as "front, rear, upper, lower, left, right", "lateral, vertical, horizontal", and "top, bottom", etc., are generally based on the azimuth or positional relationships shown in the drawings, merely to facilitate description of the present utility model and simplify the description, and these azimuth terms do not indicate and imply that the apparatus or elements referred to must have a specific azimuth or be constructed and operated in a specific azimuth, and thus should not be construed as limiting the scope of protection of the present utility model: the orientation word "inner and outer" refers to inner and outer relative to the contour of the respective component itself.

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

In addition, the terms "first", "second", etc. are used to define the components, and are only for convenience of distinguishing the corresponding components, and the terms have no special meaning unless otherwise stated, and therefore should not be construed as limiting the scope of the present utility model.

As shown in the figure, the utility model provides a clamping and feeding device for mechanical material transmission, which comprises a mechanical arm 1, wherein a clamping mechanism for clamping materials is arranged on the mechanical arm 1, the clamping mechanism comprises a clamping moving plate 2 which is hinged to the output end of the mechanical arm 1, a driving groove 4 which is arranged on the bottom surface of the clamping moving plate 2, a reverse threaded rod 5 which is horizontally rotated and arranged in the driving groove 4, two transmission threaded sleeves 6 which are symmetrically arranged on the rod body of the reverse threaded rod 5, and a driving motor 7 which is arranged on the side surface of the clamping moving plate 2, two clamping plates 3 are symmetrically arranged at the left and right sides of the bottom end of the clamping moving plate 2, the two clamping plates 3 are correspondingly connected with the two transmission threaded sleeves 6, and the output end of the driving motor 7 is fixedly connected with one end of the reverse threaded rod 5;

when the device is used, an operator can firstly connect the mechanical arm 1 and the driving motor 7 with an external power supply so that the mechanical arm 1 and the driving motor 7 can be normally started, therefore, when the materials are clamped and conveyed, the operator can firstly use the mechanical arm 1 to drive the clamping moving plate 2 to perform lifting movement until the clamping moving plate 2 is moved to the position right above the materials, the materials are positioned in the middle parts of the two clamping plates 3, then the reverse threaded rod 5 rotates in the driving groove 4 through the driving motor 7, in the rotating process of the reverse threaded rod 5, the transmission screw sleeve 6 is matched with the reverse threaded rod 5 through a threaded structure, the transmission screw sleeve 6 can quickly drive the clamping plates 3 to perform mutual approaching movement until the clamping plates 3 are in contact with the materials, and then after the materials are clamped, the mechanical arm 1 is started again to transfer the materials so as to realize the feeding operation of the materials;

according to the embodiment, though the clamping mechanism can effectively provide a reliable fixing effect for materials in the material transferring and feeding process, the mechanical arm 1 still has certain defects in the actual use process, for example, when the clamping mechanism on the mechanical arm 1 clamps cylindrical and oval materials with smooth surfaces, the clamping plate 3 in the clamping mechanism always has insufficient clamping effect on the materials, and the materials are extremely easy to drop in the transferring process, so that larger damage is generated.

In the embodiment of the utility model, the mechanical arm 1 further comprises a material receiving mechanism for preventing materials from falling, wherein the material receiving mechanism comprises a telescopic receiving part positioned under the clamping moving plate 2 and used for carrying out length adjustment in real time in cooperation with the movement of the clamping plate 3, and a rotation supplying part arranged on the clamping plate 3 and used for providing rotating force for the telescopic receiving part in a contact-pressing mode, the telescopic receiving part comprises a contraction supplying sleeve 8 and a telescopic plate 9, and the contraction supplying sleeve 8 is arranged on the plate surface of the telescopic plate 9 in a sliding mode;

when the mechanical arm 1 drives the clamping moving plate 2 to make descending movement above the materials, the rotation supply part can be firstly contacted with a table surface for placing the materials and feel the pressure of the table surface facing the rotation supply part, so that the rotation supply sleeve 8 and the expansion plate 9 can be driven to rapidly overturn ninety degrees, the clamping moving plate 2 can be conveniently positioned between the two clamping plates 3 in the further descending process, when the clamping plates 3 are mutually close to each other to clamp the materials, the clamping plates 3 can simultaneously drive the expansion plate 9 to shrink inwards of the rotation supply sleeve 8, so that the clamping process of the clamping plates 3 is not hindered, otherwise, when the clamping moving plate 3 is used for clamping the materials, the rotation supply part can reversely drive the rotation supply sleeve 8 and the expansion plate 9 to reversely overturn to a horizontal position, a material receiving platform can be effectively formed below the materials, so that the materials can be conveniently and directly dropped to the ground when the materials fall, and damage is prevented.

In another embodiment of the utility model, the telescopic bearing part further comprises two overlapped plates symmetrically arranged under the clamping moving plate 2, the overlapped plates are composed of a baffle A19 arranged on the side edge of the top surface of the telescopic sleeve 8 and a baffle B20 arranged on the side edge of the top surface of the telescopic plate 9, the top surface of the telescopic sleeve 8 is also provided with a sliding slot 21 matched with the baffle B20, and magnet plates are embedded on the top surfaces of the telescopic sleeve 8 and the telescopic plate 9;

through the arrangement of the magnet plates on the top surfaces of the shrinkage sleeve 8 and the expansion plate 9, if the materials fixed between the two clamping plates 3 are made of metal materials, the magnet plates can just form stronger attractive force on the materials after the materials fall on the top surfaces of the shrinkage sleeve 8 and the expansion plate 9 by gravity, so that the materials are stably arranged on the top surfaces of the shrinkage sleeve 8 and the expansion plate 9, and the materials are prevented from rolling off the surfaces of the two clamping plates;

the baffle A19 and the baffle B20 are arranged so as to form shielding on the materials at the side edge parts of the top surfaces of the shrinkage sleeve 8 and the expansion plate 9, prevent nonmetallic materials from rolling after falling on the top surfaces of the shrinkage sleeve 8 and the expansion plate 9, and directly separate from the surfaces of the shrinkage sleeve 8 and the expansion plate 9, and fall on the ground to be damaged, so that the baffle A19 and the baffle B20 can effectively resist the rolling trend of the materials;

in addition, through the arrangement of the sliding seam 21, when the two clamping plates 3 make a movement close to or far from each other, the telescopic sleeve 8 and the telescopic plate 9 drive the baffle A19 and the baffle B20 to make a corresponding telescopic movement, and therefore the sliding seam 21 can provide a certain movable space for the baffle B20.

In another embodiment of the utility model, the rotation supply component comprises a telescopic slot 10 vertically arranged in the inner wall of the clamping plate 3, a transmission gear 11 movably arranged in the telescopic slot 10 and a transmission toothed plate 13 slidably arranged in the telescopic slot 10, wherein the transmission toothed plate 13 is meshed with the transmission gear 11, one end of the shrinkage sleeve 8, which is far away from the telescopic plate 9, is provided with a rotating rod 12, the rotating rod 12 vertically penetrates into the telescopic slot 10 and is fixedly connected with the central shaft of the transmission gear 11, a rotation supply slot 16 for rotating the rotating rod 12 is arranged on the plate surface of the clamping plate 3, one end of the transmission toothed plate 13 is connected with a squeezing plate 14, a compression spring 15 is arranged between the squeezing plate 14 and the innermost inner wall of the telescopic slot 10, the other end of the transmission toothed plate 13 penetrates out of the telescopic slot 10, a limited rail sliding bar 17 is arranged on the side edge of the transmission toothed plate 13, and a limited rail sliding slot 18 matched with the limited rail sliding bar 17 is arranged on the inner wall of the telescopic slot 10;

when the mechanical arm 1 drives the clamping moving plate 2 to make descending movement, the transmission toothed plate 13 can be firstly contacted with a table surface for placing materials and feel pressure to shrink towards the inside of the telescopic groove 10, so that the transmission toothed plate 13 is continuously meshed with the transmission gear 11 in the shrinking process to drive the transmission gear 11 to rotate, the transmission gear 11 can drive the shrinkage sleeve 8 and the telescopic plate 9 to make the same-direction turnover through the rotating rod 12 in the rotating process until the rotating rod 12 rotates out of the rotation groove 16, and when the shrinkage sleeve 8 and the telescopic plate 9 are driven to rotate to ninety degrees, the materials can be exactly positioned between the two clamping plates 3 in the further moving process of the clamping moving plate 2, so that the two clamping plates 3 can conveniently clamp the materials;

when the transmission toothed plate 13 contracts towards the inside of the telescopic slot 10, the transmission toothed plate 13 can simultaneously drive the extrusion plate 14 to slide in the telescopic slot 10 and extrude the compression spring 15, so that the compression spring 15 deforms, in the contraction process of the transmission toothed plate 13, the rail limiting sliding bar 17 slides in the rail limiting sliding slot 18, so that the sliding track of the transmission toothed plate 13 can be limited, the stability of the transmission toothed plate 13 in the contraction process is ensured, therefore, when the clamping plate 3 finishes clamping a material, the clamping moving plate 2 gradually weakens the interference effect of the transmission toothed plate 13 and a table top in the upward displacement process, the transmission toothed plate 13 can reversely slide out of the telescopic slot 10 under the resilience force of the compression spring 15, and the transmission gear 11 is driven to reversely rotate, so that the shrinkage sleeve 8 and the telescopic plate 9 are driven to reversely rotate to a horizontal state, and the material receiving platform is effectively formed under the material, so that the material is prevented from directly falling to the ground when the material falls down, and damage is caused.

Finally, it should be noted that: the above embodiments are only for illustrating the technical solution of the present utility model, and not for limiting the same; although the utility model has been described in detail with reference to the foregoing embodiments, it will be understood by those of ordinary skill in the art that: the technical scheme described in the foregoing embodiments can be modified or some or all of the technical features thereof can be replaced by equivalents; such modifications and substitutions do not depart from the spirit of the utility model.

Claims (8)

1. A centre gripping loading attachment for mechanical material transmission, its characterized in that:

a centre gripping loading attachment for mechanical material transmission include: the mechanical arm (1) clamping mechanism, the rotating mechanism and the receiving mechanism;

the front end of the mechanical arm (1) is connected with a clamping mechanism for clamping materials;

the material receiving mechanism is rotationally connected with the clamping mechanism through the rotating mechanism, so that the material is prevented from falling.

2. The clamping and feeding device for mechanical material transfer according to claim 1, wherein:

the fixture include: the clamping device comprises a clamping moving plate (2), a clamping plate (3), a driving groove (4), a reverse threaded rod (5), a transmission threaded sleeve (6) and a driving motor (7);

the upper end of the clamping moving plate (2) is hinged with the output end of the mechanical arm (1);

a driving groove (4) is formed in the bottom surface of the clamping moving plate (2);

the reverse threaded rod (5) is arranged in the driving groove (4), and two ends of the reverse threaded rod are arranged at two ends of the driving groove (4) through bearing seats;

two transmission threaded sleeves (6) are symmetrically arranged on the rod body of the reverse threaded rod (5);

the lower parts of the two transmission screw sleeves (6) are respectively provided with a clamping plate (3), the clamping plates (3) are telescopic grooves (10) with hollow structures, and rotating mechanisms are arranged in the telescopic grooves (10);

the driving motor (7) is arranged at one end of the clamping moving plate (2), and the output end of the driving motor (7) penetrates through the clamping moving plate (2) and is fixedly connected with one end of the reverse threaded rod (5).

3. The clamping and feeding device for mechanical material transfer according to claim 2, wherein:

the rotating mechanism comprises: the device comprises a transmission gear (11), a rotating rod (12), a transmission toothed plate (13), a squeeze plate (14), a compression spring (15) and a rotation supply groove (16);

the top end of the transmission toothed plate (13) is fixedly connected with the extrusion plate (14) and is arranged in the telescopic groove (10) of the clamping plate (3) together;

a compression spring (15) is arranged between the extrusion plate (14) and the inner top wall of the expansion groove (10);

the transmission toothed plate (13) is meshed with a transmission gear (11) arranged at the lower part of the extrusion plate (14);

the rotating rod (12) vertically penetrates into the telescopic groove (10), the upper end of the rotating rod is fixedly connected with the central shaft of the transmission gear (11), and the lower end of the rotating rod is connected with the material receiving mechanism;

the rotating rod (12) is driven by the transmission toothed plate (13) to rotate, and the rotating rod (12) enters a rotating groove (16) arranged on the plate surface of the clamping plate (3) in the rotating process and used for the rotating rod (12) to rotate.

4. A clamping and feeding device for mechanical material transfer according to claim 3, characterized in that:

a limited rail sliding strip (17) is arranged on the side edge of the transmission toothed plate (13);

the inner wall of the telescopic groove (10) is provided with a rail limiting sliding groove (18) matched with the rail limiting sliding bar (17);

the rail limiting sliding strip (17) and the rail limiting sliding groove (18) are matched for use, and play a role in guiding the movement of the transmission toothed plate (13).

5. The clamping and feeding device for mechanical material transfer of claim 4, wherein:

the length of the transmission toothed plate (13) outside the lower end of the clamping plate (3) is longer than 1/4 arc length of the transmission gear (11), so that the transmission toothed plate (13) can drive the rotating rod (12) to rotate 90 degrees through the clamping plate (3).

6. A clamping and feeding device for mechanical material transfer according to claim 3, characterized in that:

the material receiving mechanism comprises: a shrinkage sleeve (8) and a telescopic plate (9);

one end of the shrinkage sleeve (8) is fixedly connected with the bottom end of a rotating rod (12);

one end of the expansion plate (9) is fixedly connected with the bottom end of the other rotating rod (12);

the free end of the shrinkage sleeve (8) is arranged on the free end of the expansion plate (9) in a sliding way to form an extensible and contractible bearing structure.

7. The clamping and feeding device for mechanical material transfer of claim 6, wherein:

magnet plates are embedded on the top surfaces of the shrinkage sleeve (8) and the expansion plate (9).

8. The clamping and feeding device for mechanical material transfer of claim 7, wherein:

two side edges of the top surface of the shrinkage sleeve (8) are respectively provided with a baffle A (19);

two side edges of the top surface of the expansion plate (9) are respectively provided with a baffle B (20);

the top surface of the shrinkage sleeve (8) is also provided with a sliding slot (21) matched with the baffle B (20).