Axial floating constant force grinding tool

Abstract

The present invention relates to an axial floating constant force grinding tool, comprising a pneumatic spindle and a floating grinding seat, the floating grinding seat comprising a mounting plate, a constant force base and a sliding base, the sliding base is provided with a mounting seat for the pneumatic spindle, the constant force base has an accommodating portion in the middle, a guide rail arranged along the axial direction and a slider sliding along the guide rail are provided in the accommodating portion, the upper side of the slider is connected with the sliding base, a guide column is provided on the rear side of the slider, a sliding hole for accommodating the guide column is correspondingly provided at the rear of the constant force base, an oil-free bushing is provided in the sliding hole, the guide column slides axially in the oil-free bushing to form a cylinder structure; a base end cover is sealingly connected to the rear side of the constant force base, an air supply path for supplying air from the rear side to the cylinder structure is processed in the base end cover; the present invention forms a cylinder structure through the guide column and the oil-free bushing, takes the guide column as a piston, supplies air through the air supply path so that the guide column is subjected to a constant thrust to realize axial constant force floating grinding, the structure is relatively simple, and the stability is good.

Description

Technical Field

[0001] The invention belongs to the field of mechanical technology, and in particular relates to an axial floating constant force grinding tool. Background Art

[0002] At present, robots are playing an increasingly important role in more manufacturing segments, and grinding, polishing, and deburring are indispensable basic processes in the manufacturing industry. With the disappearance of the demographic dividend, as well as the requirements for reducing costs and improving product quality, the market demand for grinding and polishing robots has become increasingly strong, and industrial robots are increasingly used for grinding work to replace manual labor. Pressure control is crucial for robot grinding. If you want robots to replace manual labor to do some grinding applications, you need a constant force floating mechanism between the robot and the grinding tool. For different working conditions, sometimes a radial constant force floating mechanism is required, and sometimes an axial constant force floating mechanism is required. This type of constant force floating mechanism can compensate for the comprehensive position error, ensure that the grinding tool and the workpiece being polished remain in contact, and ensure that the contact force is the pressure required by the grinding process, thereby ensuring the stability of the grinding process.

[0003] The Chinese patent with the announcement number CN116872084A and the name "A Constant Force Axial Floating Grinding Tool" discloses a constant force axial floating grinding tool, which involves the field of mechanical processing and manufacturing technology, including shutter blades, electric spindles, pneumatic muscles, position sensors, floating tension air intake joints, floating thrust air intake joints, floating tension proportional valves and floating thrust proportional valves; through pneumatic muscles, position sensors and floating thrust proportional valves, real-time adjustment of constant force control of products during the grinding process is achieved; through floating tension proportional valves, the axial floating mechanism of the grinding head is gravity matched to prevent the degradation of grinding quality due to gravity; according to the actual application situation, the pressure value of the grinding tool can be adjusted by adjusting the number of floating shafts, thereby realizing the grinding function of different occasions and different products; selecting high-precision position sensors can ensure the surface roughness and smoothness of the product. The structure of the constant force grinding and polishing mechanism is relatively complex, the processing precision requirements are high, and the product cost is high. Summary of the invention

[0004] The purpose of the present invention is to provide a design scheme for an axially floating constant force grinding tool, which realizes radial constant force control of the grinding tool by utilizing the working principle of the cylinder, and cooperates with a robot to achieve constant force polishing and grinding of the product surface.

[0005] In order to solve the above technical problems, the present invention discloses an axial floating constant force grinding tool, comprising a pneumatic spindle and a floating grinding seat for maintaining a constant force of the pneumatic spindle in the axial direction during grinding, the floating grinding seat at least comprising a mounting plate for connecting with a mechanical arm, a constant force base fixed on the mounting plate, and a sliding base mounted on the constant force base, the sliding base slides back and forth along the axial direction with a constant force during grinding, a mounting seat of the pneumatic spindle is arranged on the sliding base, the mounting seat comprises a spindle mounting seat and an upper cover, the pneumatic spindle is installed between the spindle mounting seat and the upper cover; a receiving portion is provided in the middle of the constant force base, a guide rail arranged in the axial direction and a slider sliding along the guide rail are provided in the receiving portion, the upper side of the slider is connected to the sliding base, a guide column is provided on the rear side of the slider, a sliding hole for accommodating the guide column is correspondingly provided at the rear of the constant force base, an oil-free bushing is provided in the sliding hole, the guide column slides axially in the oil-free bushing to form a cylinder structure;

[0006] The rear side of the constant force base is sealed with a base end cover, and an air supply path for supplying air from the rear side to the cylinder structure is processed inside the base end cover; when the air supply path supplies air at a constant air pressure, the guide column is pushed by the air pressure to generate a constant thrust forward, and the constant force floating of the pneumatic spindle in the axial direction is realized through the conduction of the slider and the sliding base;

[0007] There is an exhaust gap between the inner wall of the oil-free bushing and the outer wall of the guide column, so that the guide column can slide smoothly in the oil-free bushing, thereby improving the movement and response speed of the pneumatic spindle during grinding; the thrust exerted on the guide column is positively correlated with the difference between the air pressure of the air supply line and the air pressure lost through the exhaust gap.

[0008] Preferably, the guide column is sleeved with an adjusting sleeve for adjusting the exhaust volume of the exhaust gap, and a plurality of first exhaust grooves are evenly provided on the outer wall of the adjusting sleeve, and the first exhaust grooves are arranged axially; an adjusting ring is rotatably provided at one end of the adjusting sleeve near the end cover of the base, and a second exhaust groove is provided on the outer wall of the adjusting ring, and the number and arrangement of the second exhaust grooves are the same as those of the first exhaust grooves, and the protrusion between two adjacent second exhaust grooves is used to block the first exhaust groove; rotate the adjusting ring, when the second exhaust groove is opposite to the first exhaust groove, the exhaust volume of the adjusting sleeve reaches the maximum, and when the second exhaust groove completely blocks the first exhaust groove, the exhaust volume of the adjusting sleeve reaches the minimum.

[0009] Preferably, the width of the second exhaust groove is not greater than that of the first exhaust groove.

[0010] Preferably, the adjusting ring is fixed after adjustment by damping or fasteners; the diameter of the adjusting ring is smaller than the diameter of the adjusting sleeve, and when the adjusting sleeve moves with the guide column, the adjusting ring does not contact the oil-free bushing.

[0011] Preferably, the sliding hole and the end cover of the base are sealed by a sealing ring.

[0012] Preferably, the oil-free bushing is made of high-strength brass combined with graphite material to achieve lubrication of the guide column and stable operation of the grinding tool.

[0013] Preferably, the maximum axial floating distance of the sliding base is 6-12 mm.

[0014] Preferably, a guide column is provided on each side of the end of the slider.

[0015] Preferably, there is an anti-disassembly locking structure between the spindle mounting seat and the sliding base, and the anti-disassembly locking structure includes a pin, a spring and a socket, and the socket includes a part processed on the spindle mounting seat and a part processed on the sliding base; the spring supports the pin to keep the pin at the junction of the spindle mounting seat and the sliding base.

[0016] Preferably, the guide rail is a heavy-load linear guide rail for withstanding the torsional force during grinding.

[0017] The axial floating constant force grinding tool of the present invention has at least the following advantages:

[0018] 1. The present invention forms a cylinder structure through a guide column and an oil-free bushing, uses the guide column as a piston, and supplies air through an air supply line to subject the guide column to a constant thrust to achieve axial constant-force floating grinding. The structure is relatively simple and has good stability.

[0019] 2. In order to make the thrust exerted on the guide column of the product consistent under the same air pressure, the air pressure loss of the product at the exhaust gap must be consistent. According to this design concept, an adjusting sleeve for adjusting the exhaust volume of the exhaust gap is sleeved on the guide column, and a first exhaust groove is arranged on the outer side of the adjusting sleeve. An adjusting ring with a second exhaust groove is rotatably arranged at the end of the adjusting sleeve. The exhaust volume of the first exhaust groove is adjusted by adjusting the alignment of the first exhaust groove and the second exhaust groove, thereby adjusting the exhaust gap, which makes up for the lack of product processing precision and ensures the consistency of the product output constant force. BRIEF DESCRIPTION OF THE DRAWINGS

[0020] Figure 1 It is the general assembly diagram of the axial floating constant force grinding tool of the present invention;

[0021] Figure 2 A schematic diagram of the internal structure of the axial floating constant force grinding tool of the present invention;

[0022] Figure 3 It is a schematic diagram of the internal structure of the constant force base and the base end cover in the present invention;

[0023] Figure 4 is a three-dimensional structural diagram of a constant force base in an embodiment of the present invention;

[0024] Figure 5It is an exploded view of the axial floating constant force grinding tool of the present invention;

[0025] Figure 6 It is a structural schematic diagram of the adjusting sleeve in the present invention.

[0026] The numbers in the accompanying drawings are respectively: main shaft 1, sliding base 2, upper cover 3, main shaft mounting seat 4, pin 4-1, spring 4-2, constant force base 5, linear guide rail 5-1, oil-free bushing 5-2, guide column 5-3, sealing ring 5-4, base end cover 6, mounting plate 7, air supply line 8, adjusting sleeve 9, first exhaust groove 9-1, second exhaust groove 9-2, adjusting ring 9-3, and protrusion 9-4. DETAILED DESCRIPTION

[0027] The present invention is further described in detail below through examples so that those skilled in the art can implement the invention with reference to the description.

[0028] It should be understood that the terms such as “having”, “including” and “comprising” used herein do not exclude the existence or addition of one or more other elements or combinations thereof.

[0029] Example 1

[0030] like Figure 1-5 As shown, an axial floating constant force grinding tool comprises a pneumatic spindle 1 and a floating grinding seat for maintaining a constant force in the axial direction of the pneumatic spindle 1 during grinding. The floating grinding seat at least comprises a mounting plate 7 for connecting to a robot arm, a constant force base 5 fixed on the mounting plate 7, and a sliding base 2 mounted on the constant force base 5. During grinding, the sliding base 2 slides forward and backward along the axial direction with a constant force. A mounting seat for the pneumatic spindle 1 is provided on the sliding base 2. The mounting seat comprises a spindle mounting seat 4 and an upper cover 3. The pneumatic spindle 1 is mounted on the spindle mounting seat 4 and the upper cover 3; the constant force base 5 has a receiving portion in the middle, in which a guide rail arranged along the axial direction and a slider 5-1 sliding along the guide rail are provided, the upper side of the slider 5-1 is connected to the sliding base 2, and a guide column 5-3 is provided on the rear side of the slider 5-1, and a sliding hole for accommodating the guide column 5-3 is correspondingly provided at the rear of the constant force base 5, and an oil-free bushing 5-2 is provided in the sliding hole, and the guide column 5-3 slides axially in the oil-free bushing 5-2 to form a cylinder structure; in this embodiment, a guide column 5-3 is provided on each side of the end of the slider 5-1.

[0031] like Figure 5 As shown, the rear side of the constant force base 5 is sealed and connected with a base end cover 6, and an air supply path 8 for supplying air from the rear side to the cylinder structure is processed inside the base end cover 6; when the air supply path 8 supplies air at a constant air pressure, the guide column 5-3 is pushed by the air pressure to generate a constant thrust forward, which is transmitted through the slider 5-1 and the sliding base 2 to achieve constant force floating of the pneumatic spindle 1 in the axial direction;

[0032] like Figure 4 As shown, there is an exhaust gap between the inner wall of the oil-free bushing 5-2 and the outer wall of the guide column 5-3 (the oil-free bushing 5-2 is in contact with the guide column 5-3 and there is a gap locally), so that the guide column 5-3 can slide smoothly in the oil-free bushing 5-2, thereby improving the movement and response speed of the pneumatic spindle 1 during grinding; the thrust received by the guide column 5-3 is positively correlated with the difference between the air pressure of the air supply gas path and the air pressure lost through the exhaust gap. It is worth noting that if the inner wall of the oil-free bushing 5-2 and the outer wall of the guide column 5-3 are tightly matched, there will be a large resistance when the air pressure pushes the guide column 5-3, and the result of the unsmoothness is that the constant force output of the guide column 5-3 is unstable and the response is delayed, which cannot meet the processing requirements; and due to the existence of various errors, the size of the reserved exhaust gap is not easy to control.

[0033] The sliding hole and the base end cover 6 are sealed and connected via a sealing ring 5-4.

[0034] The oil-free bushing 5-2 is made of high-strength brass and graphite material to achieve lubrication of the guide column 5-3, thereby achieving stable operation of the grinding tool.

[0035] The maximum axial floating distance of the sliding base 2 is 6-12 mm.

[0036] The guide rail adopts a heavy-load linear guide rail to withstand the torsional force during grinding.

[0037] like Figure 2 As shown, there is an anti-disassembly locking structure between the spindle mounting seat 4 and the sliding base 2, and the anti-disassembly locking structure includes a latch 4-1, a spring 4-2 and a socket, and the socket includes a part processed on the spindle mounting seat 4 and a part processed on the sliding base 2; the spring 4-2 supports the latch 4-1 to keep the latch 4-1 at the junction of the spindle mounting seat 4 and the sliding base 2. The anti-disassembly locking structure is a commonly used anti-disassembly mechanism in the industry, which can prevent professionals from mistakenly disassembling the module, resulting in inaccurate positioning or thrust changes.

[0038] Example 2

[0039] like Figure 6As shown, it is similar to Example 1, except that in order to make the thrust on the guide column 5-3 of the product consistent under the same air pressure, the air pressure loss of the product at the exhaust gap must be consistent. According to this design concept, an adjusting sleeve 9 for adjusting the exhaust volume of the exhaust gap is sleeved on the guide column 5-3 (the guide column 5-3 is used as a carrier for installing the adjusting sleeve 9 at this time, and the adjusting sleeve 9 is installed on the guide column 5-3 by screws, etc., and is not in direct contact with the oil-free bushing 5-2. The machining accuracy requirements for the guide column 5-3 are low, and the adjusting sleeve 9 in direct contact with the oil-free bushing 5-2 requires higher machining accuracy). The outer wall of the adjusting sleeve is evenly provided with a plurality of first exhaust grooves 9-1, and the first exhaust grooves 9-1 are arranged along the axial direction; the adjusting sleeve 9 is near the bottom An adjusting ring 9-3 is rotatably provided at one end of the seat end cover 6, and a second exhaust groove 9-2 is provided on the outer side wall of the adjusting ring. The number and arrangement of the second exhaust grooves 9-2 are the same as those of the first exhaust grooves 9-1, and the protrusion 9-4 between two adjacent second exhaust grooves is used to block the first exhaust groove 9-1. When the adjusting ring 9-3 is rotated, when the second exhaust groove 9-2 is opposite to the first exhaust groove 9-1, the exhaust volume of the adjusting sleeve 9 reaches the maximum, and when the second exhaust groove 9-2 completely blocks the first exhaust groove 9-1, the exhaust volume of the adjusting sleeve 9 reaches the minimum.

[0040] The width of the second exhaust groove 9 - 2 is not greater than that of the first exhaust groove 9 - 1 .

[0041] The adjusting ring 9-3 is fixed after adjustment by damping or fasteners; the diameter of the adjusting ring 9-3 is smaller than the diameter of the adjusting sleeve 9, and when the adjusting sleeve 9 moves with the guide column 5-3, the adjusting ring 9-3 does not contact the oil-free bushing 5-2.

[0042] If the exhaust gap needs to be adjusted again, a professional can open the sliding base 2, remove the base end cover 6, and properly rotate the adjustment ring 9-3.

[0043] Although the embodiments of the present invention have been disclosed as above, they are not limited to the applications listed in the specification and the implementation modes. They can be fully applied to various fields suitable for the present invention. For those familiar with the art, additional modifications can be easily implemented. Therefore, without departing from the general concept defined by the claims and the scope of equivalents, the present invention is not limited to the specific details and the embodiments shown and described herein.

Claims

1. An axial floating constant force grinding tool, characterized in that: The invention comprises a pneumatic spindle (1) and a floating grinding seat for maintaining a constant force in the axial direction of the pneumatic spindle (1) during grinding, wherein the floating grinding seat at least comprises a mounting plate (7) for connecting to a robot arm, a constant force base (5) fixed on the mounting plate (7), and a sliding base (2) mounted on the constant force base (5); during grinding, the sliding base (2) slides forward and backward along the axial direction with a constant force; a mounting seat for the pneumatic spindle (1) is arranged on the sliding base (2); the mounting seat comprises a spindle mounting seat (4) and an upper cover (3); the pneumatic spindle (1) is mounted Between the main shaft mounting seat (4) and the upper cover (3); the middle part of the constant force base (5) has a receiving portion, the receiving portion is provided with a guide rail arranged along the axial direction and a slider (5-1) sliding along the guide rail, the upper side of the slider (5-1) is connected to the sliding base (2), the rear side of the slider (5-1) is provided with a guide column (5-3), the rear part of the constant force base (5) is correspondingly provided with a sliding hole for accommodating the guide column (5-3), the sliding hole is provided with an oil-free bushing (5-2), and the guide column (5-3) slides axially in the oil-free bushing (5-2) to form a cylinder structure; The rear side of the constant force base (5) is sealedly connected to a base end cover (6), and an air supply path (8) is machined inside the base end cover (6) for supplying air from the rear side to the cylinder structure; when the air supply path (8) supplies air at a constant air pressure, the guide column (5-3) is pushed by the air pressure to generate a constant thrust forward, which is transmitted through the slider (5-1) and the sliding base (2), thereby realizing constant force floating of the pneumatic spindle (1) in the axial direction; An exhaust gap exists between the inner wall of the oil-free bushing (5-2) and the outer wall of the guide column (5-3), so that the guide column (5-3) can slide smoothly in the oil-free bushing (5-2), thereby improving the movement and response speed of the pneumatic spindle (1) during grinding; the thrust force exerted on the guide column (5-3) is positively correlated with the difference between the air pressure of the air supply path (8) and the air pressure lost through the exhaust gap; The guide column (5-3) is sleeved with an adjustment sleeve (9) for adjusting the exhaust volume of the exhaust gap, and the outer wall of the adjustment sleeve is evenly provided with a plurality of first exhaust grooves (9-1), and the first exhaust grooves (9-1) are arranged along the axial direction; an adjustment ring (9-3) is rotatably provided at one end of the adjustment sleeve (9) near the base end cover (6), and the outer wall of the adjustment ring is provided with second exhaust grooves (9-2), the number and arrangement of the second exhaust grooves (9-2) are the same as those of the first exhaust grooves (9-1), and the protrusion (9-4) between two adjacent second exhaust grooves is used to shield the first exhaust groove (9-1).

2. The axial floating constant force grinding tool according to claim 1, characterized in that: The adjusting ring (9-3) is rotated, and when the second exhaust groove (9-2) faces the first exhaust groove (9-1), the exhaust volume of the adjusting sleeve (9) reaches a maximum, and when the second exhaust groove (9-2) completely blocks the first exhaust groove (9-1), the exhaust volume of the adjusting sleeve (9) reaches a minimum.

3. The axial floating constant force grinding tool according to claim 2, characterized in that: The width of the second exhaust groove (9-2) is no greater than that of the first exhaust groove (9-1).

4. The axial floating constant force grinding tool according to claim 3, characterized in that: The adjusting ring (9-3) is fixed after adjustment by means of a damper or a fastener; the diameter of the adjusting ring (9-3) is smaller than the diameter of the adjusting sleeve (9); when the adjusting sleeve (9) moves with the guide column (5-3), the adjusting ring (9-3) does not contact the oil-free bushing (5-2).

5. The axial floating constant force grinding tool according to claim 1, characterized in that: The sliding hole and the base end cover (6) are sealed and connected via a sealing ring (5-4).

6. The axial floating constant force grinding tool according to claim 1, characterized in that: The oil-free bushing (5-2) is made of high-strength brass combined with graphite material to achieve lubrication of the guide column (5-3), thereby achieving stable operation of the grinding tool.

7. The axial floating constant force grinding tool according to claim 1, characterized in that: The maximum axial floating distance of the sliding base (2) is 6-12 mm.

8. The axial floating constant force grinding tool according to claim 1, characterized in that: A guide column (5-3) is provided on each side of the end of the sliding block (5-1).

9. The axial floating constant force grinding tool according to claim 1, characterized in that: An anti-disassembly locking structure is provided between the spindle mounting seat (4) and the sliding base (2), the anti-disassembly locking structure comprising a latch (4-1), a spring (4-2) and a socket, the socket comprising a portion machined on the spindle mounting seat (4) and a portion machined on the sliding base (2); the spring (4-2) supports the latch (4-1) so that the latch (4-1) is retained at the junction of the spindle mounting seat (4) and the sliding base (2).

10. The axial floating constant force grinding tool according to claim 1, characterized in that: The guide rail adopts a heavy-load linear guide rail to withstand the torsional force during grinding.

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