CN220446100U

CN220446100U - L-shaped steel structural member surface polishing equipment

Info

Publication number: CN220446100U
Application number: CN202321931386.9U
Authority: CN
Inventors: 张远; 胡磊; 胡勇; 胡友州; 刘旭阳; 秦石柱; 黄晓飞
Original assignee: Henan Huangguo Steel Structure Co ltd
Current assignee: Henan Huangguo Steel Structure Co ltd
Priority date: 2023-07-18
Filing date: 2023-07-18
Publication date: 2024-02-06
Anticipated expiration: 2033-07-18

Abstract

The utility model relates to a polishing device for the surface of an L-shaped steel structural member, which comprises a placing table, wherein the top end of a rotating column is rotationally connected with the inner top end of a driving box, and the bottom end of the rotating column extends to the outside of the driving box and is fixedly connected with a polishing disc.

Description

L-shaped steel structural member surface polishing equipment

Technical Field

The utility model relates to the technical field of steel structures, in particular to surface polishing equipment for an L-shaped steel structural member.

Background

Polishing is a surface modification technology, generally refers to a processing method for changing physical properties of a material surface by friction by means of a rough object (sand paper containing particles with higher hardness, and the like), and mainly aims to obtain specific surface roughness, and a large amount of rust can appear on the surface of a steel structure after the steel structure is placed for a long time and subjected to sun-drying and rain, so that a polishing and rust removing device is required to be used for polishing the surface of the steel structure before the steel structure is used for meeting the use requirement. When polishing the surface of an L-shaped steel structural member, it is necessary to use an L-shaped steel structural member surface polishing apparatus.

The polishing equipment in the prior art can not adjust the polishing angle of the polishing disc, when polishing the L-shaped part body, the polishing disc is generally required to be used, and because the shape of the L-shaped part body is unique, in the polishing process, if the angle position of the polishing disc is not adjusted, the polishing equipment can not comprehensively polish every surface of the L-shaped part body through the polishing disc, if the clamping is continuously replaced on the surface of the L-shaped part body, the polishing disc can polish the surface of the L-shaped part body, but the process is time-consuming and labor-consuming, and the polishing efficiency of the L-shaped part body by the polishing equipment is affected.

Disclosure of Invention

The utility model aims to provide polishing equipment for the surface of an L-shaped steel structural member, which aims to solve the problems in the background technology.

In order to achieve the above purpose, the utility model provides a polishing device for the surface of an L-shaped steel structural member, which comprises a placing table, wherein a mounting plate is arranged above the placing table, the bottom of the mounting plate is fixedly connected with a transmission box, rotating rods are symmetrically arranged in the transmission box, two ends of each rotating rod are respectively in rotating connection with the front inner wall and the rear inner wall of the transmission box, one end of each rotating rod extends to the outside of the transmission box and is fixedly connected with a first knob, the outside of one rotating rod is fixedly connected with a driving gear, the outside of the other rotating rod is fixedly connected with a driven gear meshed with the driving gear, connecting plates are symmetrically arranged on the outside of the other rotating rod, guide grooves for the connecting plates to move are formed in the outside of the transmission box, the bottoms of the two connecting plates are fixedly connected with a driving box, rotating columns are arranged in the inside of the driving box, the top ends of each rotating column are in rotating connection with the top end of the inside of the driving box, and the bottom end of each rotating column extends to the outside of the driving box and is fixedly connected with a polishing disc.

As the further improvement of this technical scheme, the front end surface of first knob runs through and has offered the mounting hole that is used for installing the dead lever, the one end of dead lever extends to the outside of first knob and fixedly connected with arm-tie, the outside fixedly connected with of dead lever is contradicted the dish, the outside cover of dead lever is equipped with reset spring, reset spring is contradicted between contradicting dish and first knob, the guide way that supplies the dead lever activity has been seted up to the front end surface annular of transmission case.

As a further improvement of the technical scheme, the back end surface symmetry of placing the platform is equipped with the backup pad, two the last fixed surface of backup pad is connected with the roof, the bottom symmetry of roof is equipped with electric telescopic handle, two electric telescopic handle's flexible end all carries out fixed connection with the upper surface of mounting panel.

As the further improvement of this technical scheme, place the bottom fixedly connected with regulating plate of platform, the inside of regulating plate is equipped with the threaded rod, the one end of threaded rod rotates with the inside wall of regulating plate to be connected, the other end of threaded rod extends to the outside of regulating plate and fixedly connected with second knob, the outside threaded connection of threaded rod has the screw thread piece, the guide way that supplies the screw thread piece activity has all been seted up with the contact surface of placing the platform to the regulating plate, the last fixed surface of screw thread piece is connected with the processing board.

As a further improvement of this technical scheme, the bottom symmetry of processing board is equipped with the fixed plate, two the inside of fixed plate all is equipped with the lead screw, two the one end of lead screw all rotates with the inner wall of fixed plate to be connected, two the other end of lead screw all extends to the outside of fixed plate, one of them the other end fixedly connected with third knob of lead screw, another the other end fixedly connected with limiting disc of lead screw, two carry out the transmission through belt cooperation drive wheel between the lead screw, two the outside of lead screw is all symmetrical to be equipped with the movable block, two the guide way that supplies the movable block to move about is all offered to the contact surface of fixed plate and processing board, every two the equal fixedly connected with support bar of upper surface of support bar, two the equal symmetry of opposite side of splint is equipped with the connecting rod, every two the equal fixedly connected with grip block of the other end of connecting rod, two the opposite side of grip block all has the protection pad, two be equipped with L type spare body of bonding between the protection pad.

As a further improvement of the technical scheme, the motor is fixedly connected to the bottom end of the inside of the driving box, the driving rod is fixedly connected to the output shaft of the motor through the coupler, the rotating gear is fixedly connected to the other end of the driving rod, and the driven gear meshed with the rotating gear is fixedly connected to the outside of the rotating column.

This among L shaped steel structural member surface equipment of polishing, through dwang, first knob and the connecting plate that set up, when needs are adjusted the angular position of polishing dish, only need rotate first knob, first knob drives one of them dwang and rotates in step this moment, one of them dwang drives the driving gear again and rotates in step, the driving gear drives driven gear and rotates in step, driven gear drives another dwang and rotates in step, another dwang drives two connecting plates again and rotates in step, two connecting plates drive the driving case again and remove in step, the driving case drives the synchronous removal of polishing dish again, can adjust the angular position of polishing dish according to actual demand this moment, thereby be convenient for polish the dish and polish the processing to the different faces of L type spare body, labour saving and time saving.

This among L shaped steel structural member surface equipment of polishing, thereby through the arm-tie that sets up, dead lever and reset spring, thereby when needs rotate first knob to the angular position of polishing dish adjusts, only need the pulling arm-tie, the arm-tie drives the dead lever and removes in step this moment, the dead lever drives the conflict dish and removes in step, at the in-process that the conflict dish removed, can extrude reset spring, when the dead lever breaks away from in the guide way of transmission case front end surface, can rotate first knob, after the angular position of polishing dish is adjusted, loosen the arm-tie, reset spring resets this moment, drive the dead lever and remove in step, when the dead lever pegged graft to the guide way of transmission case front end surface, can lock the processing to first knob, thereby prevent polishing dish at the in-process of polishing to L type spare body, first knob takes place to rotate, the angular position of polishing dish takes place the skew.

Drawings

FIG. 1 is a schematic overall perspective view of the present utility model;

FIG. 2 is a schematic view of a cut-away perspective of the drive housing of the present utility model;

FIG. 3 is a schematic view of a transmission case in a cut-away perspective;

FIG. 4 is a schematic view of a cut-away perspective of an adjusting plate according to the present utility model;

FIG. 5 is a schematic view showing a cut-away perspective structure of a fixing plate according to the present utility model;

FIG. 6 is an enlarged schematic view of the area A in FIG. 2;

fig. 7 is an enlarged schematic view of the area B in fig. 3.

Reference numerals: 1. placing table, 2, support plate, 3, top plate, 4, electric telescopic rod, 5, mounting plate, 6, transmission case, 7, driving case, 8, processing plate, 9, adjusting plate, 10, second knob, 11, fixing plate, 12, rotating column, 13, polishing disc, 14, threaded rod, 15, screw block, 16, third knob, 17, belt, 18, limit disc, 19, screw rod, 20, moving block, 21, support bar, 22, clamping plate, 23, connecting rod, 24, clamping plate, 25, motor, 26, driving rod, 27, rotating gear, 28, driven gear, 29, first knob, 30, rotating rod, 31, driving gear, 32, driven gear, 33, connecting plate, 34, pulling plate, 35, fixing rod, 36, abutting disc, 37, return spring, 38, L-shaped member body.

Detailed Description

The following description of the embodiments of the present utility model will be made clearly and completely with reference to the accompanying drawings, in which it is apparent that the embodiments described are only some embodiments of the present utility model, but not all embodiments.

Referring to fig. 1-7, the polishing device for the surface of an L-shaped steel structural member comprises a placing table 1, a mounting plate 5 is arranged above the placing table 1, a transmission box 6 is fixedly connected to the outer portion of the mounting plate 5, rotating rods 30 are symmetrically arranged in the transmission box 6, two ends of the two rotating rods 30 are respectively and rotatably connected with the front inner wall and the rear inner wall of the transmission box 6, one end of one rotating rod 30 extends to the outer portion of the transmission box 6 and is fixedly connected with a first knob 29, the main purpose of the polishing device is to drive one rotating rod 30 to synchronously rotate, a driving gear 31 is fixedly connected to the outer portion of one rotating rod 30, a driven gear 32 meshed with the driving gear 31 is fixedly connected to the outer portion of the other rotating rod 30, connecting plates 33 are symmetrically arranged on the outer portion of the other rotating rod 30, the main purpose of the polishing disc 13 is to drive the angle adjustment, guide grooves for the movement of the connecting plates 33 are formed in the outer portion of the transmission box 6, a driving box 7 is fixedly connected to the bottom of the two connecting plates 33, a rotating column 12 is arranged in the inner portion of the driving box 7, the top end of the rotating column 12 is rotatably connected to the inner top end of the driving box 7, and the bottom end of the rotating column 12 extends to the outer portion of the driving column 7 is fixedly connected with a polishing body 38, and is used for polishing body 38.

The working principle is as follows: when the angle position of the polishing disc 13 needs to be adjusted, only the first knob 29 is required to be rotated, at this time, the first knob 29 drives one of the rotating rods 30 to synchronously rotate, one of the rotating rods 30 drives the driving gear 31 to synchronously rotate, the driving gear 31 drives the driven gear 32 to synchronously rotate, the driven gear 32 drives the other rotating rod 30 to synchronously rotate, the other rotating rod 30 drives the two connecting plates 33 to synchronously rotate, the two connecting plates 33 drive the driving box 7 to synchronously move, the driving box 7 drives the polishing disc 13 to synchronously move, at this time, the angle position of the polishing disc 13 can be adjusted according to actual requirements, and therefore polishing of different faces of the L-shaped workpiece body 38 by the polishing disc 13 is facilitated, and time and labor are saved.

Considering that when the angular position adjustment of the polishing disc 13 is completed, the first knob 29 needs to be subjected to locking treatment, thereby preventing the polishing disc 13 from rotating in the polishing process, the angular position of the polishing disc 13 is offset, so the front end surface of the first knob 29 is penetrated and provided with a mounting hole for mounting the fixing rod 35, one end of the fixing rod 35 extends to the outside of the first knob 29 and is fixedly connected with the pulling plate 34, the outside of the fixing rod 35 is fixedly connected with the abutting disc 36, the outside of the fixing rod 35 is sleeved with the reset spring 37, the reset spring 37 abuts against between the abutting disc 36 and the first knob 29, a guide groove for the fixing rod 35 to move is annularly formed in the front end surface of the transmission box 6, when the first knob 29 needs to rotate to adjust the angular position of the polishing disc 13, only the pulling plate 34 needs to be pulled, the fixing rod 35 is driven to synchronously move at this moment, the fixing rod 35 drives the abutting disc 36 to synchronously move, the reset spring 37 can be extruded in the process of the moving of the fixing rod 35, when the fixing rod 35 is separated from the guide groove on the front end surface of the transmission box 6, namely, the first knob 29 can be rotated, the first knob 29 is moved to the position of the transmission box 13 is prevented from moving, and the transmission box 13 is prevented from moving in the process of the transmission box 13, the transmission box is moved to the angular position of the transmission box is adjusted, and the transmission box is prevented from moving the rotary joint is moved to the rotary joint of the polishing disc 13, and the rotary joint is moved.

In order to adjust the height position of the polishing disc 13, so that the polishing disc 13 is convenient to polish the L-shaped workpiece body 38, the supporting plates 2 are symmetrically arranged on the surface of the rear end of the placement table 1, the top plates 3 are fixedly connected with the upper surfaces of the two supporting plates 2, the bottoms of the top plates 3 are symmetrically provided with the electric telescopic rods 4, the telescopic ends of the two electric telescopic rods 4 are fixedly connected with the upper surfaces of the mounting plates 5, when the height position of the polishing disc 13 is required to be adjusted, the electric telescopic rods 4 start to operate, the mounting plates 5 are driven to synchronously move the polishing disc 13, and at the moment, the height position of the polishing disc 13 can be adjusted, so that the outer surface of the L-shaped workpiece body 38 is convenient to polish.

Considering when carrying out the processing of polishing to L type spare body 38, therefore, the bottom fixedly connected with regulating plate 9 of placing platform 1, the inside of regulating plate 9 is equipped with threaded rod 14, the one end of threaded rod 14 rotates with the inside wall of regulating plate 9 to be connected, the other end of threaded rod 14 extends to the outside of regulating plate 9 and fixedly connected with second knob 10, threaded rod 14's external screw thread is connected with screw thread piece 15, the guide way that supplies screw thread piece 15 activity is all offered to the contact surface of regulating plate 9 with placing platform 1, screw thread piece 15's upper surface fixedly connected with processing board 8, when the position to L type spare body 38 need be carried out the removal, only need rotate second knob 10, at this moment second knob 10 drives threaded rod 14 and rotates in step, screw thread piece 15 moves in step in the outside of threaded rod 14, drive processing board 8 moves in step, processing board 8 drives L type spare body 38 and moves in step, can very conveniently carry out the position to L type spare body 38 in this moment, thereby the processing of polishing of grinding disc 13 is carried out to it conveniently.

Because the L-shaped part body 38 needs to be fixed and clamped when being polished, displacement and other conditions are prevented in the polishing process, the bottom of the processing plate 8 is symmetrically provided with the fixed plates 11, the interiors of the two fixed plates 11 are respectively provided with the screw rods 19, one ends of the two screw rods 19 are respectively connected with the inner wall of the fixed plates 11 in a rotating way, the other ends of the two screw rods 19 are respectively extended to the exterior of the fixed plates 11, the other end of one screw rod 19 is fixedly connected with the third knob 16, the other end of the other screw rod 19 is fixedly connected with the limiting disc 18, the two screw rods 19 are in transmission connection by matching with the driving wheel through the belt 17, the exteriors of the two screw rods 19 are symmetrically provided with the movable blocks 20, the contact surfaces of the two fixed plates 11 and the processing plate 8 are respectively provided with the guide grooves for the movable blocks 20, the upper surfaces of each two movable blocks 20 are respectively fixedly connected with the supporting bars 21, the upper surfaces of the two supporting bars 21 are fixedly connected with clamping plates 22, the opposite sides of the two clamping plates 22 are symmetrically provided with connecting rods 23, the other ends of the two connecting rods 23 are fixedly connected with clamping plates 24, the opposite sides of the two clamping plates 24 are adhered with protection pads, an L-shaped part body 38 is arranged between the two protection pads, when the L-shaped part body 38 is required to be fixedly clamped, the L-shaped part body 38 is only required to be placed on the processing plate 8, at the moment, the third knob 16 is rotated, the third knob 16 drives one of the screw rods 19 to synchronously rotate, because the two screw rods 19 are in transmission connection through the belt 17 matched with a driving wheel, at the moment, the two screw rods 19 synchronously rotate, the plurality of moving blocks 20 synchronously move outside the screw rods 19 to drive the supporting bars 21 to synchronously move, the supporting bars 21 drive the clamping plates 22 to synchronously move, the clamping plate 22 drives the clamping plate 24 to synchronously move, and the L-shaped part body 38 can be effectively clamped through the clamping plate 24 at the moment, so that the polishing disc 13 is convenient to polish.

In addition, in order to polish the L-shaped part body 38 effectively, so the motor 25 is fixedly connected to the bottom end of the inside of the driving box 7, the driving rod 26 is fixedly connected to the output shaft of the motor 25 through the coupler, the rotating gear 27 is fixedly connected to the other end of the driving rod 26, the driven gear 28 meshed with the rotating gear 27 is fixedly connected to the outside of the rotating column 12, when the L-shaped part body 38 needs to be polished, the motor 25 starts to operate, the driving rod 26 is driven to rotate synchronously, the driving rod 26 drives the rotating gear 27 to rotate synchronously, the rotating gear 27 drives the driven gear 28 to rotate synchronously, the driven gear 28 drives the rotating column 12 to rotate synchronously, and the rotating column 12 drives the polishing disc 13 to rotate synchronously, so that the L-shaped part body 38 can be polished effectively through the polishing disc 13.

When the polishing device for the surface of the L-shaped steel structural member in the embodiment is specifically used, the L-shaped member body 38 is firstly placed on the processing plate 8, the third knob 16 is rotated, the second knob 16 drives one screw rod 19 to synchronously rotate, the processing plate 8 is synchronously moved due to the fact that the two screw rods 19 are in transmission connection through the belt 17 and the driving wheels, the two screw rods 19 synchronously rotate, the plurality of moving blocks 20 synchronously move outside the screw rods 19, the supporting bar 21 is driven to synchronously move, the supporting bar 21 drives the clamping plate 22 to synchronously move, the clamping plate 22 drives the clamping plate 24 to synchronously move, the L-shaped member body 38 can be effectively clamped through the clamping plate 24 at the moment, after the L-shaped member body 38 is clamped, the second knob 10 drives the threaded rod 14 to synchronously rotate, the threaded block 15 synchronously moves outside the threaded rod 14, the processing plate 8 synchronously moves, the L-shaped member body 38 is driven to synchronously move through the belt 17, the L-shaped member body 38 can be quite conveniently moved at the moment, when the L-shaped member body 38 moves to the lower side of the polishing plate 13, the electric motor 4 drives the grinding plate 5 drives the grinding plate 13 to synchronously move, the grinding plate 5 drives the grinding plate 13 to synchronously rotate, the grinding plate 25 rotates the grinding plate 13 simultaneously, the grinding plate 25 rotates the grinding plate 13 synchronously, the grinding plate 5 rotates the grinding plate and the grinding plate 13 synchronously rotates, the grinding plate 25 and the grinding plate 25 synchronously rotates, and the grinding plate 25 synchronously rotates the grinding plate and the grinding plate 25 to synchronously rotates the grinding plate and the grinding plate 25 to rotate the grinding plate and the grinding plate 25. When the different faces of the L-shaped part body 38 need to be polished, only the pulling plate 34 is pulled, at the moment, the pulling plate 34 drives the fixing rod 35 to synchronously move, the fixing rod 35 drives the abutting disc 36 to synchronously move, the reset spring 37 can be extruded in the moving process of the abutting disc 36, when the fixing rod 35 is separated from the guide groove on the front end surface of the transmission case 6, the first knob 29 can be rotated, at the moment, the first knob 29 drives one rotating rod 30 to synchronously rotate, one rotating rod 30 drives the driving gear 31 to synchronously rotate, the driving gear 31 drives the driven gear 32 to synchronously rotate, the driven gear 32 drives the other rotating rod 30 to synchronously rotate, the other rotating rod 30 drives the two connecting plates 33 to synchronously rotate, the two connecting plates 33 drive the driving case 7 to synchronously move, the driving case 7 drives the polishing disc 13 to synchronously move, at the moment, and the angle position of the polishing disc 13 can be adjusted according to actual requirements, thereby the polishing disc 13 can conveniently polish the different faces of the L-shaped part body 38, after the angle position adjustment of the polishing disc 13 is completed, the pulling plate 30 drives the reset spring 37 to synchronously rotate, namely, the reset spring 37 can synchronously drive the two connecting plates 33 to synchronously rotate, the two connecting plates 33 can simultaneously rotate, the driving plates 35 can synchronously move, the fixing plate 35 can be synchronously move to the front end of the transmission case 13, and the transmission case can be locked, and the transmission case can be synchronously locked, and the fixed by the front end of the transmission case can be locked, and time-saved, and the time can be saved, and the time can be saved.

Claims

1. The utility model provides an L shaped steel structural member surface equipment of polishing, is including placing platform (1), its characterized in that: the upper part of the placing table (1) is provided with a mounting plate (5), the bottom of the mounting plate (5) is fixedly connected with a transmission case (6), the inside of the transmission case (6) is symmetrically provided with rotating rods (30), two ends of the two rotating rods (30) are respectively in rotating connection with the front inner wall and the rear inner wall of the transmission case (6), one end of one rotating rod (30) extends to the outside of the transmission case (6) and is fixedly connected with a first knob (29), the outside of one rotating rod (30) is fixedly connected with a driving gear (31), the outside of the other rotating rod (30) is fixedly connected with a driven gear (32) meshed with the driving gear (31), and the outside of the other rotating rod (30) is symmetrically provided with a connecting plate (33); the outside of transmission case (6) has offered the guide way that supplies connecting plate (33) activity, and the bottom fixedly connected with driving case (7) of two connecting plates (33), and the inside of driving case (7) is equipped with rotation post (12), and the top of rotation post (12) rotates with the inside top of driving case (7) to be connected, and the bottom of rotation post (12) extends to the outside of driving case (7) and fixedly connected with polishing dish (13).

2. The surface grinding device for an L-shaped steel structural member according to claim 1, wherein: the front end surface of first knob (29) runs through the mounting hole of seting up being used for installing dead lever (35), and the one end of dead lever (35) extends to the outside of first knob (29) and fixedly connected with arm-tie (34), and the outside fixedly connected with of dead lever (35) is contradicted dish (36), and the outside cover of dead lever (35) is equipped with reset spring (37), and reset spring (37) contradicts between contradicting dish (36) and first knob (29), and the guide way that supplies dead lever (35) activity is offered to the front end surface annular of transmission case (6).

3. The surface grinding device for an L-shaped steel structural member according to claim 1, wherein: the rear end surface symmetry of placing platform (1) is equipped with backup pad (2), and the last fixed surface of two backup pads (2) is connected with roof (3), and the bottom symmetry of roof (3) is equipped with electric telescopic handle (4), and the flexible end of two electric telescopic handle (4) all carries out fixed connection with the upper surface of mounting panel (5).

4. The surface grinding device for an L-shaped steel structural member according to claim 1, wherein: the bottom fixedly connected with regulating plate (9) of placing platform (1), the inside of regulating plate (9) is equipped with threaded rod (14), the one end of threaded rod (14) rotates with the inside wall of regulating plate (9) to be connected, the other end of threaded rod (14) extends to the outside of regulating plate (9) and fixedly connected with second knob (10), the outside threaded connection of threaded rod (14) has screw thread piece (15), the guide way that supplies screw thread piece (15) activity has all been seted up with the contact surface of placing platform (1) to regulating plate (9), the last fixed surface of screw thread piece (15) is connected with processing board (8).

5. The surface grinding device for the L-shaped steel structural member according to claim 4, wherein: the bottom symmetry of processing board (8) is equipped with fixed plate (11), the inside of two fixed plates (11) all is equipped with lead screw (19), the guide way that supplies movable block (20) activity is all offered to the contact surface of two fixed plates (11), the equal fixedly connected with support bar (21) of upper surface of every two movable blocks (20), the equal fixedly connected with splint (22) of upper surface of two support bars (21), the opposite side of the equal symmetry of another other end fixedly connected with connecting rod (22) is equipped with connecting rod (23), the other end fixedly connected with limiting disc (18) of another lead screw (19), carry out transmission connection through belt (17) cooperation drive wheel between two lead screws (19), the outside of two lead screws (19) all symmetry is equipped with movable block (20), the guide way that supplies movable block (20) all has been offered to the contact surface of two fixed plates (11) and processing board (8), the equal fixedly connected with support bar (21) of upper surface of two movable blocks (22), the equal fixedly connected with splint (24) of the opposite side of two splint (22), the equal fixedly connected with connecting rod (24) is equipped with connecting rod (23), the opposite side is equipped with protection pad (38) between two opposite protection pads.

6. The surface grinding device for an L-shaped steel structural member according to claim 1, wherein: the inside bottom fixedly connected with motor (25) of drive box (7), the output shaft of motor (25) passes through shaft coupling fixedly connected with actuating lever (26), and the other end fixedly connected with of actuating lever (26) rotates gear (27), and the outside fixedly connected with of spliced pole (12) is with driven gear (28) that rotates gear (27) engaged with.