Tubular inner surface grinding and polishing device and method

Abstract

The invention relates to the technical field of inner surface grinding, and discloses a tubular inner surface grinding and polishing device and method.The tubular inner surface grinding and polishing device comprises an operation table, a grinding assembly and a main control system; a roller set is arranged on the side, close to the grinding assembly, of the operation table. A front limiting piece is arranged in a gap in the front side, facing the polishing assembly, of the roller set; the roller group is used for placing a tubular workpiece, and the roller rotation direction of the roller group is perpendicular to the axial direction of the tubular workpiece; each roller has an inclination angle along the axial direction of the tubular workpiece; the main control system is electrically connected with the driving device and the grinding assembly. According to the scheme, the grinding mode that the rollers drive the workpiece to rotate is utilized, and the deformation risk of the clamped workpiece is avoided; the specially-arranged rollers and the front limiting piece are used for limiting rotation of the workpiece, and the problems that oil exists on the surface of the workpiece and displacement possibly occurs when the rollers drive the workpiece to rotate are solved; the overlap ratio of possible displacement of the workpiece and the grinding path of the grinding head when the workpiece is driven by the roller is high due to roller inclination and parameter adaptive setting, and the grinding quality can be ensured even if the workpiece displaces.

Description

Technical Field

[0001] The invention relates to the technical field of inner surface grinding, and in particular to a tubular inner surface grinding and polishing device and method. Background Art

[0002] At present, the on-board hydrogen cylinders widely used in hydrogen fuel cell vehicles in the domestic market are 35MPa III and 70MPa bottles. The interior of the bottle is an aluminum alloy liner and the outside is wrapped with carbon fiber composite materials to ensure the strength and safety of the bottle.

[0003] The aluminum alloy liner in the on-board hydrogen cylinder is mainly used to store high-pressure hydrogen and bears the main fatigue performance of the cylinder. The aluminum alloy liner must meet the quality requirements of high pressure resistance, light weight and corrosion resistance to ensure the safety and reliability of stable storage of hydrogen. In particular, the inner surface of the aluminum alloy liner that is in direct contact with hydrogen must meet high-precision quality requirements such as smoothness, uniformity, no scratches, no defects, and low surface roughness to reduce hydrogen adsorption and release and improve hydrogen storage efficiency and safety. These requirements ensure the long-term stable performance of hydrogen cylinders under high pressure and high temperature environments.

[0004] The key to improving the quality of the inner surface of the aluminum alloy liner is to grind and polish the inner surface before the liner is formed. The conventional aluminum alloy liner is a tubular long straight line and a tail arc structure. The grinding part is the entire inner surface of the tubular long straight line part. There is oil on the surface of the liner after the previous processing. The difficulty in grinding such tubular workpieces is that most of the existing equipment for grinding tubular inner walls is dedicated and has low adaptability. The workpiece needs to be clamped and fixed for a long time during grinding. Since the aluminum alloy liner is ground into a narrow and long tubular straight line part, the liner itself is an aluminum profile with oil on the surface. The machine needs to have appropriate force and clamp the middle part to maintain the clamping balance and stability. This long-term clamping method will cause local slight deformation. For ordinary workpieces, this local slight deformation is within the allowable error range and has no effect on the quality of the finished product. However, there are obvious safety hazards for vehicle-mounted hydrogen cylinders carrying high-pressure flammable gases. Therefore, the existing conventional grinding equipment alone cannot meet the requirements for grinding the inner surface of the aluminum alloy liner. In order to eliminate such local defects, experienced operators usually adjust the grinding direction, position, speed and intensity according to the location of the defects during the equipment grinding process. In order to ensure the grinding accuracy, safety of use and a certain pass rate, the overall processing production efficiency is affected. Summary of the invention

[0005] The present invention intends to provide a tubular inner surface grinding and polishing device, which optimizes the inner surface grinding and polishing method suitable for aluminum cup-shaped bodies or aluminum tubes, conforms to the characteristics of such tubular workpieces, changes the clamping grinding method into an automatically driven workpiece rotation grinding method, has stable positioning, uniform force, and completely avoids the risk of local deformation. The workpiece rotation and grinding actions are matched, the grinding force is balanced, and the grinding is uniform. The grinding quality can be ensured without adjustment, thereby improving production efficiency.

[0006] The basic scheme provided by the present invention is: a tubular inner surface grinding and polishing device, comprising an operating table, a grinding component and a main control system; the grinding component is arranged on one side of the operating table;

[0007] A roller group is arranged on one side of the operating table close to the grinding assembly; a front stopper is arranged at the front gap of the roller group facing the grinding assembly; a driving device for driving the rollers to roll is connected to the roller group; the roller group is used to place the tubular workpiece, and the rotation direction of the rollers of the roller group is perpendicular to the axial direction of the tubular workpiece; the rollers of the roller group all have an inclination angle along the axial direction of the tubular workpiece, and the end of the roller close to the front stopper is the lower end;

[0008] The grinding assembly comprises a feeding mechanism, a grinding head unit for grinding the inner surface of a pipe workpiece, and an extension rod connecting the feeding mechanism and the grinding head unit; the extension rod is located above the roller assembly, and its length extends along the axial direction of the tubular workpiece; the feeding mechanism is used to drive the extension rod to drive the grinding head unit to rotate along the rotation direction of the roller and move along the axial direction of the tubular workpiece;

[0009] The main control system is electrically connected to the driving device and the grinding assembly.

[0010] The invention is based on a tubular inner surface grinding and polishing device and also provides a tubular inner surface grinding and polishing method.

[0011] The method comprises:

[0012] Set the operating parameters of the drive device, grinding assembly and cleaning assembly through the main control system;

[0013] In response to the processing instruction, the robot grips the tubular workpiece and places it above the roller assembly, and the front end of the tubular workpiece rests on the front limiter; the proximity switch on the front limiter transmits the workpiece arrival signal to the main control system;

[0014] After receiving the workpiece arrival signal transmitted by the proximity switch, the main control system sends a grinding instruction, controls the feed mechanism to drive the grinding head unit to move to the position corresponding to the center of the front end of the tubular workpiece; controls the driving device to drive the roller group to roll to drive the pipe workpiece to rotate; after the roller group rolls for a preset time, controls the feed mechanism to drive the grinding head unit to move to the inner wall opening of the front end of the tubular workpiece, controls the feed mechanism to drive the grinding head unit to rotate and move to the inside of the tubular workpiece until the grinding head unit moves to the set end point, wherein the roller speed of the roller group matches the speed, feed speed, and downward pressure deformation of the grinding head unit; during the rotation of the grinding head unit, controls the cleaning component to spray water from the nozzle.

[0015] The working principle and advantages of the present invention are as follows: compared with the prior art, this scheme specifically proposes a grinding and polishing device and method suitable for aluminum cup-shaped bodies or aluminum tubes, and optimizes the original grinding method that requires the use of a clamp to clamp the workpiece for a long time to a grinding method that uses a roller to drive the workpiece to rotate, thereby avoiding the risk of workpiece deformation caused by the clamping method, ensuring the grinding quality, and improving production efficiency.

[0016] The specially arranged roller is used to drive the workpiece to rotate during the grinding process. With the cooperation of the front limiter, the workpiece is kept in a rotation limit position, the overall positioning of the workpiece is stable, the force is evenly applied, and clamping is avoided. At the same time, the problem of oil on the workpiece surface and the possible displacement of the workpiece when the roller drives the workpiece to rotate is solved. On the basis of the specially arranged roller, the motion parameters of the grinding head and the roller are reasonably adapted, so that the rolling speed of the roller of the roller group and the rotation and movement speed of the grinding head of the grinding head unit are matched, and the unit contact area of ​​the grinding head and the roller is reasonable, so that the grinding force of the entire grinding process is balanced and the grinding is even. While the workpiece is rotating and grinding, the processing area does not affect the processed area. The special inclination angle design of the roller, under the reasonable adaptation of the motion parameters of the grinding head and the roller, can make the possible displacement of the workpiece when the roller drives the workpiece to rotate have a high degree of overlap with the grinding path of the grinding head unit, so that even if the workpiece shifts, it will not affect the grinding, and the grinding quality can be ensured. BRIEF DESCRIPTION OF THE DRAWINGS

[0017] Figure 1 A schematic structural diagram of a tubular inner surface grinding and polishing device provided in Embodiment 1 of the present invention;

[0018] Figure 2 The present invention is a schematic flow chart of a method for grinding and polishing a tubular inner surface provided in the first embodiment of the present invention. DETAILED DESCRIPTION

[0019] The following is a further detailed description through specific implementation methods:

[0020] The symbols in the drawings of the specification include: operating table 1, roller 2, front limiter 3, workpiece 4, feeding mechanism 5, grinding head unit 6, extension rod 7, water tank 8, water outlet pipe 81, water return pipe 82, nozzle 83, main control system 9.

[0021] Embodiment 1

[0022] Basically as attached Figure 1 Shown is a tubular inner surface grinding and polishing device, comprising an operating table 1, a grinding component and a main control system 9; the grinding component is arranged on one side of the operating table 1.

[0023] A roller group is provided on one side of the operating table 1 close to the grinding component, and the rollers 2 of the roller group are arranged in a matrix, and can be reasonably configured according to the diameter and length of a conventional aluminum alloy liner workpiece. For example, the width of the roller group is greater than the diameter of the liner, and the length of the roller group is greater than the length of the tubular straight section of the aluminum alloy liner, to ensure that the contact surface between the workpiece and the roller group is reasonable, the roller group can stably drive the workpiece to rotate, and the roller arrangement density is adapted to the feed speed of the grinding head to ensure that the support surface of the workpiece at each grinding point is uniformly stressed; the roller is made of a material that will not cause wear to the surface of the aluminum alloy liner. In this embodiment, the rollers 2 are cylindrical rollers 2 of equal height; the roller group is connected to a driving device for driving the rollers 2 to roll, and the driving device can be a driving motor; the roller group is used to place a tubular workpiece 4, and the rotation direction of the rollers 2 of the roller group is perpendicular to the axial direction of the tubular workpiece 4, wherein the axial direction of the tubular workpiece 4 is as shown in FIG. Figure 1 The tubular workpiece 4 can be a single-mouth cup-shaped body or a double-mouth aluminum tube. This grinding method is to eliminate the inner surface defects, and the grinding amount is small.

[0024] The front gap of the roller group toward the grinding assembly is provided with a front limit piece 3. Specifically, the gap distance between the front limit piece 3 and the nearest row of rollers 2 can be 5-10mm, which will not affect the rotation of the workpiece 4 and can also prevent the workpiece 4 from shifting. The height of the limit block is designed to be small, slightly close to the edge of the workpiece port, not exceeding the thickness of the workpiece, and will not interfere with the grinding head. In other embodiments, the rear gap of the roller group away from the grinding assembly is provided with a rear limit piece, and the front and rear are limited simultaneously, so as to further reduce the risk of displacement of the workpiece 4 during rotation and ensure the grinding quality.

[0025] The rollers 2 of the roller group all have an inclination angle along the axial direction of the tubular workpiece 4, and the end of the roller 2 close to the front limit piece 3 is the lower end; specifically, the inclination angle can be 5-10°, and this data is determined through repeated testing and grinding. Together with other parameters of the present scheme, it can make the possible displacement path of the workpiece 4 when the roller 2 drives the workpiece 4 to rotate match the grinding path of the grinding head unit 6, and even if the workpiece 4 shifts, it will not affect the grinding, thereby ensuring the grinding quality.

[0026] The grinding assembly includes a feeding mechanism 5, a grinding head unit 6 for grinding the inner surface of the pipe workpiece 4, and an extension rod 7 connecting the feeding mechanism 5 and the grinding head unit 6; the extension rod 7 is located above the roller group, and its length extends axially along the tubular workpiece 4; the feeding mechanism 5 is used to drive the extension rod 7 to drive the grinding head unit 6 to rotate along the rotation direction of the roller 2 and move axially along the tubular workpiece 4.

[0027] Specifically, the grinding head unit 6 includes a grinding head disc and N grinding heads installed on the grinding head disc, N is an integer and at least 1, and the grinding head spacing angle is 360 / N; the grinding head is installed at the front of the grinding head disc, and can be installed alone, or 2 or 3 are evenly distributed along the circumference of the grinding head disc; when there is one grinding head, the grinding head is arranged along the length direction of the extension rod 7; when there are two grinding heads, they are arranged at an interval of 180 degrees; when there are three grinding heads, they are arranged at an interval of 120 degrees. The grinding head is a fine sand grain grinding head, and the grinding head can have different mesh numbers to achieve different grinding and polishing effects.

[0028] The device also includes a cleaning component electrically connected to the main control system 9; the cleaning component includes a connected water supply device and a nozzle 83; the nozzle 83 is installed near the grinding head unit 6; the water supply device includes a water tank 8, a water outlet pipe 81 and a water return pipe 82, one end of the water outlet pipe 81 is connected to the water supply area of ​​the water tank 8, and the other end is connected to the nozzle 83 through the feeding mechanism 5 and the extension rod 7, so that the water in the water supply area is driven to be sprayed out from the nozzle 83; a water tank is provided on the operating table 1, one end of the water return pipe 82 is connected to the water tank, and the other end is connected to the water return area of ​​the water tank 8, and the cleaned water is sent from the water tank to the water return area through the water return pipe for treatment. The water tank 8 is provided with a filtering device, and the filtered slag is stored in the water tank 8 and can be cleaned regularly.

[0029] The main control system 9 is electrically connected to the driving device, the grinding assembly and the cleaning assembly. The front limit block is provided with a proximity switch for detecting the arrival of the workpiece 4, and the proximity switch is electrically connected to the main control system 9 for transmitting a workpiece arrival signal to automatically start the grinding program.

[0030] like Figure 2 As shown, based on the above-mentioned tubular inner surface grinding and polishing device, this solution provides a tubular inner surface grinding and polishing method, the method comprising:

[0031] The main control system 9 is used to set the operating parameters of the driving device, grinding assembly and cleaning assembly, and the roller speed of the roller group matches the speed, feed speed and downward pressure deformation of the grinding head unit; in this embodiment, the workpiece diameter is 200-700mm and the weight is ≤400kg. The grinding head unit 6, i.e., the grinding head, has a speed of 5000-10000 rpm, a feed speed of 300-500mm / min, and a downward pressure deformation of 3-5mm; the driving device drives the roller 2 at a speed of 600-3000 rpm. After repeated testing, the data is obtained that the grinding parameters are adapted to the workpiece, and the inner wall surface defects are eliminated with minimum energy consumption and maximum efficiency to ensure the grinding quality effect.

[0032] In response to the processing instruction, the robot grips the tubular workpiece 4 and places it above the roller 2 of the roller assembly, and the front end of the tubular workpiece 4 rests on the front limit member 3; the proximity switch on the front limit member 3 transmits the workpiece 4 in place signal to the main control system 9.

[0033] After receiving the workpiece 4 arrival signal transmitted by the proximity switch, the main control system 9 sends a grinding instruction, and the program starts to run automatically, and starts automatic grinding and polishing. Specifically, based on the control program, the feed mechanism 5 is controlled to drive the grinding head unit 6 to move to the corresponding position of the center of the front end of the tubular workpiece 4; the driving device is controlled to drive the roller 2 to roll; after the roller group rolls for a preset time, the preset time can be 30s-1min, to ensure that the workpiece rotates normally, the feed mechanism 5 is controlled to drive the grinding head unit 6 to move to the inner wall of the front end of the tubular workpiece 4, and the grinding head is pressed down reasonably, and the feed mechanism 5 is controlled to drive the grinding head unit 6 to rotate and move to the inside of the tubular workpiece 4 until the grinding head unit 6 moves to the set end point; during the rotation of the grinding head unit 6, the cleaning component is controlled to spray water from the nozzle 83.

[0034] The number of round trips of the grinding head from the inner wall of the front end of the tubular workpiece 4 to the set end point can be set to achieve different grinding effects; when there are multiple grinding heads, after grinding head No. 1 is finished, the grinding head disc can be controlled to rotate 180° or 120°, and the next grinding head can be switched to perform grinding work to improve the quality of grinding and polishing. After the first workpiece is polished, the robot grabs it and transfers it to the tray; the robot then grabs the next workpiece and places it on the roller 2 of the operating table 1 to start a new round of grinding and polishing.

[0035] The present embodiment provides a tubular inner surface grinding and polishing device and method. Compared with the prior art, the present solution changes the original grinding method that requires the use of a clamp to clamp the workpiece for a long time into a grinding method that uses a roller to drive the workpiece to rotate, thereby avoiding the risk of workpiece deformation caused by the clamping method; in addition, a specially arranged roller is used to maintain the limit of the workpiece rotation with the cooperation of a front limit member, thereby solving the problem of oil on the workpiece surface and the possible displacement of the workpiece when the roller drives the workpiece to rotate; and the special inclination angle design of the roller can make the possible displacement path of the workpiece when the roller drives the workpiece to rotate adapted to the grinding path of the grinding head unit, so that even if the workpiece shifts, it will not affect the grinding, thereby ensuring the grinding quality.

[0036] Embodiment 2

[0037] What is different from the first embodiment is that the heights of the rollers 2 of the roller group are not equal. The height of the rollers 2 gradually increases along the axial direction of the tubular workpiece 4, and the height of the rollers close to the front limit piece is lower, so that the workpiece as a whole has an angle of inclination toward the front limit piece. The angle may be slightly smaller than the inclination angle of the roller, which may be 3-5 degrees, so that the inclination angle of the workpiece as a whole and the inclination angle of the roller are adapted to each other, which is conducive to the function of guiding out water. When grinding, flushing water can flush the ground slag out of the inner surface of the pipe in time, and the grinding effect is better. At the same time, the force against the front limit block is appropriate to avoid too tight adhesion to affect the rotation of the workpiece.

[0038] The above is only an embodiment of the present invention. The common sense such as the known specific structure and characteristics in the scheme is not described in detail here. The ordinary technicians in the relevant field are aware of all the common technical knowledge in the technical field of the invention before the application date or priority date, can obtain all the existing technologies in the field, and have the ability to apply the conventional experimental means before that date. The ordinary technicians in the relevant field can improve and implement the scheme in combination with their own abilities under the enlightenment given by this application. Some typical known structures or known methods should not become obstacles for the ordinary technicians in the relevant field to implement this application. It should be pointed out that for the technicians in this field, without departing from the structure of the present invention, several deformations and improvements can be made, which should also be regarded as the protection scope of the present invention, and these will not affect the effect of the implementation of the present invention and the practicality of the patent.

Claims

1. A tubular inner surface grinding and polishing device, characterized in that: It includes an operating table, a grinding component and a main control system; the grinding component is arranged on one side of the operating table; A roller group is arranged on one side of the operating table close to the grinding assembly; a front stopper is arranged at the front gap of the roller group facing the grinding assembly; a driving device for driving the rollers to roll is connected to the roller group; the roller group is used to place the tubular workpiece, and the rotation direction of the rollers of the roller group is perpendicular to the axial direction of the tubular workpiece; the rollers of the roller group all have an inclination angle along the axial direction of the tubular workpiece, and the end of the roller close to the front stopper is the lower end; The grinding assembly comprises a feeding mechanism, a grinding head unit for grinding the inner surface of a pipe workpiece, and an extension rod connecting the feeding mechanism and the grinding head unit; the extension rod is located above the roller assembly, and its length extends along the axial direction of the tubular workpiece; the feeding mechanism is used to drive the extension rod to drive the grinding head unit to rotate along the rotation direction of the roller and move along the axial direction of the tubular workpiece; The main control system is electrically connected to the driving device and the grinding assembly.

2. A tubular inner surface grinding and polishing device according to claim 1, characterized in that: The rollers of the roller group are arranged in a matrix.

3. A tubular inner surface grinding and polishing device according to claim 2, characterized in that: The inclination angle of the roller is 5-10°.

4. A tubular inner surface grinding and polishing device according to claim 1, characterized in that: The grinding head unit includes a grinding head disk and N grinding heads installed on the grinding head disk, N is an integer and is at least 1, and the grinding head interval angle is 360 / N.

5. The tubular inner surface grinding and polishing device according to claim 1, characterized in that: A rear limiter is arranged in the rear gap of the roller assembly away from the grinding assembly.

6. A tubular inner surface grinding and polishing device according to claim 1, characterized in that: The front limit block is provided with a proximity switch for detecting whether the workpiece is in place, and the proximity switch is electrically connected to the main control system.

7. A tubular inner surface grinding and polishing device according to claim 1, characterized in that: It also includes a cleaning component electrically connected to the main control system; the cleaning component includes a connected water supply device and a nozzle; the nozzle is installed near the grinding head unit.

8. The tubular inner surface grinding and polishing device according to claim 1, characterized in that: The roller height of the roller assembly gradually increases along the axial direction of the tubular workpiece, and the roller height close to the front limiter is lower.

9. A method for grinding and polishing a tubular inner surface, characterized in that: Using a tubular inner surface grinding and polishing device according to any one of claims 1 to 8; the method comprises: Set the operating parameters of the drive device, grinding assembly and cleaning assembly through the main control system; In response to the processing instruction, the robot grips the tubular workpiece and places it above the roller assembly, and the front end of the tubular workpiece rests on the front limiter; the proximity switch on the front limiter transmits the workpiece arrival signal to the main control system; After receiving the workpiece arrival signal transmitted by the proximity switch, the main control system sends a grinding instruction, controls the feed mechanism to drive the grinding head unit to move to the position corresponding to the center of the front end of the tubular workpiece; controls the driving device to drive the roller group to roll to drive the pipe workpiece to rotate; after the roller group rolls for a preset time, controls the feed mechanism to drive the grinding head unit to move to the inner wall opening of the front end of the tubular workpiece, controls the feed mechanism to drive the grinding head unit to rotate and move to the inside of the tubular workpiece until the grinding head unit moves to the set end point, wherein the roller speed of the roller group matches the speed, feed speed, and downward pressure deformation of the grinding head unit; during the rotation of the grinding head unit, controls the cleaning component to spray water from the nozzle.

10. A method for grinding and polishing a tubular inner surface according to claim 9, characterized in that: The rotation speed of the grinding head unit is 5000-10000 rpm, the feed speed is 300-500mm / min, and the downward deformation is 3-5mm; the roller rotation speed of the roller group is 600-3000 rpm.

Images