A bta tool connector based on dynamic pressure oil film

Abstract

The present application relates to the technical field of BTA tool, particularly relates to a BTA tool connector, concretely to a BTA tool connector based on dynamic pressure oil film, in order to solve the problems of the existing BTA tool connector structure being relatively complex and the precision adjustment range of the dynamic pressure oil film pressure being small, a new structure of the BTA tool connector based on dynamic pressure oil film is provided, which comprises a connector base, a plurality of adjusting assemblies, each adjusting assembly comprises a tilting pad, a torsional spring, a telescopic component, a fixed rod, the telescopic component comprises two bent plates, two connecting plates, two telescopic blocks, a compression spring, a top column, a bottom column and a piezoelectric ceramic stack, when the piezoelectric ceramic stack is elongated, the bending angle of the two bent plates is reduced but is always in a bent state, the compression spring changes from an initial state to a compressed state, the angle of the tilting pad changes, and the roundness and appearance quality of the deep hole processed by the BTA tool are better improved.

Description

Technical Field

[0001] The present invention relates to the technical field of BTA tools, and in particular to a BTA tool connector, specifically a BTA tool connector based on dynamic pressure oil film. Background Art

[0002] BTA tools are deep-hole machining tools with internal chip removal. Their radial motion trajectory determines the roundness and morphology of the deep hole. Uncovering the offsetting mechanism between the motion trajectory and various factors is key to ensuring deep-hole roundness. With the increasing demand for deep-hole roundness, the traditional single-factor passive control method for BTA tool deep-hole roundness is no longer able to meet the requirements of BTA tool deep-hole roundness under the influence of multiple factors.

[0003] Prior art has proposed a research theory for using a dynamic oil film to actively control the roundness of deep holes processed by BTA tools. This involves measuring the radial force generated during the process using a radial force sensor, calculating the required dynamic oil film pressure based on the magnitude of the radial force, and then adjusting the dynamic oil film pressure to balance the radial force generated during deep hole processing, thereby improving the roundness and morphology quality of deep holes processed by BTA tools. To form a dynamic oil film, three conditions must be met: first, a wedge-shaped gap must be formed between the two workpieces; second, the gap between the two workpieces must be continuously filled with liquid; and third, the surfaces of the two workpieces must have a relative sliding speed, and the direction of movement must ensure that the liquid flows in from the large end of the gap cross-section and out from the small end. Therefore, how to form a dynamic oil film is one of the key issues in achieving dynamic oil film active control of the roundness and morphology of deep holes processed by BTA tools.

[0004] The patent number is 202310302155.X, and the patent name is a BTA tool connector with a variable angle tilting bearing. The patent provides a BTA tool connector structure for realizing the formation of a dynamic pressure oil film. However, the structure uses a combination of piezoelectric ceramics and memory alloys as a telescopic component. Specifically, coarse adjustment is first performed through the memory alloy, and then fine adjustment is performed through the piezoelectric ceramics. However, since the deformation of the memory alloy is not linear, the precise control range is limited, and the displacement of the piezoelectric ceramic is very small, only one thousandth of its own height, and the precise adjustment range is at the micron level, resulting in a smaller range of precise adjustment, which makes the precise adjustment range of the dynamic pressure oil film pressure that can be generated smaller and the precise control accuracy is low. At the same time, the structure is more complex and the manufacturing cost is higher. Summary of the Invention

[0005] In order to solve the problems of the existing BTA tool connector having a complex structure and a small precise adjustment range of the dynamic oil film pressure, the present invention provides a new BTA tool connector based on dynamic oil film with a completely different structure.

[0006] The present invention is achieved by adopting the following technical solutions:

[0007] A BTA tool connector based on a dynamic pressure oil film includes a cylindrical connector base, one end of which is a tool connection end for connecting to a BTA tool (as is known to those skilled in the art, the connection end of a BTA tool is typically provided with external threads, so the tool connection end connected to the BTA tool is typically provided with internal threads that are compatible with the connection end of the BTA tool), and the other end of the connector base is a drill rod connection end for connecting to a drill rod. An annular groove is coaxially provided on the outer circumferential surface of the central portion of the connector base, and a plurality of adjustment components are evenly and intermittently distributed circumferentially within the annular groove, with a circumferential adjustment spacing provided between adjacent adjustment components.

[0008] Each adjustment assembly includes a tilting pad, a torsion spring, a telescopic member, and a fixed rod. The tilting pad is located in an annular groove. The cross-section of the tilting pad is sector-annular, and the length direction of the tilting pad is consistent with the axial arrangement direction of the connector base. The fixed rod is axially arranged and rotates through the tilting pad (the tilting pad has a certain thickness). The two ends of the fixed rod are respectively fixed to the two side walls of the annular groove of the connector base. The torsion spring is located at one end of the circumference of the inner wall of the tilting pad. One end of the torsion spring is fixedly connected to the inner wall of the tilting pad, and the other end of the torsion spring is fixedly connected to the bottom wall of the annular groove of the connector base. The other end of the circumference of the inner wall of the tilting pad is provided with an axially arranged adjustment groove. The telescopic member is located below the adjustment groove, and when the telescopic member is extended or retracted, the angle of the tilting pad can be changed (it is well known to those skilled in the art that if the angle of the tilting pad is to be changed, the adjustment groove must be wide enough to prevent the adjustment groove from hindering the rotation of the tilting pad when the angle of the tilting pad is rotated).

[0009] The telescopic component includes two strip-shaped bent plates, two connecting plates, two telescopic blocks, a compression spring, a top column, a bottom column, and a strip-shaped piezoelectric ceramic stack controlled by a power driver. The two bent plates are arranged in a radial direction and bent toward each other in the middle. The two connecting plates are respectively fixed vertically at the two ends of the two bent plates. The two telescopic blocks are respectively fixed to the outer side surfaces of the two connecting plates. The annular groove-shaped two side walls of the connector base are provided with axially arranged telescopic grooves whose cross-sections are larger than the cross-sections of the telescopic blocks. One of the telescopic blocks is placed in the corresponding telescopic groove and can slide radially in the telescopic groove. A compression spring is provided between the other telescopic block and the corresponding telescopic groove, and the other telescopic block can slide radially in the corresponding telescopic groove. The piezoelectric ceramic stack is located between the two bent plates and its two ends are respectively connected to the inner sides of the two connecting plates. The top surface of the top column is fixedly connected to the middle of the outer side surface of the bent plate close to the tilting pad, the top surface of the top column is against the top wall of the adjustment groove of the tilting pad, the top surface of the bottom column is fixed to the middle of the outer side surface of the bent plate close to the base of the connector, and the bottom surface of the bottom column is against the base of the connector. When the piezoelectric ceramic stack is extended, the bending angle of the two bent plates decreases but is always in a bent state (the two bent plates are always in a bent state, which means that when the piezoelectric ceramic stack is extended to the limit, the two bent plates are still in a bent state, but their bending angles are very small. This design makes it easy for the two bent plates to contract and bend along their original bending directions when the piezoelectric ceramic stack is shortened, thereby realizing effective adjustment of the angle of the tilting pad), the compression spring changes from the initial state to the compressed state, and the angle of the tilting pad changes.

[0010] Working principle: When a certain voltage value is applied through the power controller to control the deformation of the piezoelectric ceramic stack, for example, when the piezoelectric ceramic stack is stretched, the compression spring is compressed, and the bending angle of the two bent plates is reduced, so that the other circumferential end of the tilting pad is lifted. When the piezoelectric ceramic stack is shortened, the compression spring changes to the initial state, and the bending angle of the two bent plates becomes larger. Due to the supporting effect of the torsion spring, one circumferential end of the tilting pad is lifted and the other end is lowered, so that different oil wedge gaps are generated between the tilting pad and the inner wall of the deep hole of the workpiece, thereby realizing the change of the dynamic pressure oil film pressure between the tilting pad and the inner wall of the deep hole of the workpiece, so as to balance the radial force generated during the deep hole processing, thereby improving the roundness and morphology quality of the deep hole processed by the BTA tool.

[0011] Among them, the relationship between the deformation and voltage of the piezoelectric ceramic stack in this scheme is linear, so its expansion and contraction can be precisely controlled; at the same time, since it has the characteristics of a large free forming range and its precise adjustment range is at the millimeter level, it can achieve precise adjustment over a large range; in addition, this scheme realizes the angle adjustment of the tilting pad through a torsion spring and a telescopic mechanism, which has a simple structure, is easy to implement and has a low manufacturing cost; in addition, the angle adjustment ratio of the tilting pad can be achieved by adjusting the position of the fixed rod. The closer the fixed rod is to the telescopic mechanism, the greater the angle adjustment ratio of the tilting pad. It has a wide range of applicability and a large range of precise adjustment.

[0012] The beneficial effects of the present invention are as follows: The BTA tool connector based on dynamic pressure oil film in the present invention integrates electromechanical and mechanical properties, has a simple structure, low cost, and is easy to use. By controlling the deformation of the piezoelectric ceramic stack and cooperating with the torsion spring and the fixed rod to change the lifting angle of the tilting pad, the precise adjustment range is large, thereby more accurately changing the dynamic pressure oil film pressure, thereby better improving the roundness and morphology quality of the BTA tool in deep hole processing. BRIEF DESCRIPTION OF THE DRAWINGS

[0013] The accompanying drawings, which are incorporated in and constitute a part of this specification, illustrate embodiments consistent with the invention and, together with the description, serve to explain the principles of the invention.

[0014] In order to more clearly illustrate the embodiments of the present invention or the technical solutions in the prior art, the following briefly introduces the drawings required for use in the embodiments or the description of the prior art. Obviously, for ordinary technicians in this field, other drawings can be obtained based on these drawings without paying any creative labor.

[0015] Figure 1 It is a schematic diagram of the overall structure of the present invention;

[0016] Figure 2 for Figure 1 The structural diagram in which one tilting pad is removed;

[0017] Figure 3 for Figure 1 A structural diagram in which one regulating component is removed;

[0018] Figure 4 Schematic diagram of the structure of the adjustment component with part of the piezoelectric ceramic stack removed Figure 1 ;

[0019] Figure 5 Schematic diagram of the structure of the adjustment component with part of the piezoelectric ceramic stack removed Figure 2 ;

[0020] Figure 6 It is a structural schematic diagram of the telescopic member;

[0021] Figure 7 Schematic diagram of the structure of the connector base.

[0022] In the figure: 1-connector base, 2-tool connection end, 3-drill rod connection end, 4-annular groove, 5-tilt pad, 6-torsion spring, 7-piezoelectric ceramic stack, 8-fixed rod, 9-adjustment groove, 10-telescopic member, 101-bent plate, 102-connecting plate, 103-telescopic block, 104-compression spring, 105-top column, 106-bottom column, 107-telescopic groove, 11-support rod. DETAILED DESCRIPTION

[0023] In order to more clearly understand the above-mentioned purposes, features and advantages of the present application, the schemes of the present application will be further described below. It should be noted that the embodiments of the present application and the features in the embodiments can be combined with each other without conflict.

[0024] In the description, it should be noted that the terms “first”, “second” are only for the purpose of description, and cannot be understood as indicating or implying relative importance. It should be noted that, unless otherwise explicitly specified and limited, the terms “mounting”, “connecting”, “connection” should be understood in a broad sense, for example, it can be fixed connection, or detachable connection, or integrally connected; it can be mechanical connection, or electrical connection; it can be directly connected, or indirectly connected through an intermediate medium, or the communication inside two elements. For those skilled in the art, the specific meanings of the above terms can be understood according to the specific circumstances.

[0025] In the following description, many specific details are set forth in order to provide a thorough understanding of the present application, but the present application can also be implemented in other different ways from those described herein; obviously, the examples in the description are only some of the embodiments of the present application, not all the embodiments.

[0026] The specific embodiments of the present application will be described in detail below with reference to the accompanying drawings.

[0027] As shown in Figures 1 to 7 A BTA tool connector based on dynamic pressure oil film includes a cylindrical connector base 1, one end of the connector base 1 is a tool connecting end 2 for connecting with a BTA tool (it is well known to those skilled in the art that the connecting end of the BTA tool is usually provided with external threads, so the tool connecting end 2 for connecting with the BTA tool is usually provided with internal threads matched with the connecting end of the BTA tool), the other end of the connector base 1 is a drill rod connecting end 3 for connecting with a drill rod, and a ring-shaped groove 4 is coaxially arranged on the outer circumferential surface of the middle part of the connector base 1, a plurality of adjusting assemblies are uniformly and intermittently arranged on the inner circumference of the ring-shaped groove 4, and a circumferential adjusting interval is arranged between two adjacent adjusting assemblies;

[0028] Each adjustment assembly includes a tilting pad 5, a torsion spring 6, a telescopic member 10, and a fixed rod 8. The tilting pad 5 is located in the annular groove 4. The cross section of the tilting pad 5 is a sector ring and the length direction of the tilting pad 5 is consistent with the axial arrangement direction of the connector base 1. The fixed rod 8 is axially arranged and rotates through the tilting pad 5 (the tilting pad 5 has a certain thickness). The two ends of the fixed rod 8 are respectively fixed to the two side walls of the annular groove of the connector base 1. The torsion spring 6 is located at one end of the circumference of the inner wall side of the tilting pad 5. One end of the torsion spring 6 is fixedly connected to the inner wall of the tilting pad 5, and the other end of the torsion spring 6 is fixedly connected to the bottom wall of the annular groove 4 of the connector base 1. An axially arranged adjustment groove 9 is formed at the other circumferential end of the inner wall of the tilting pad 5. A telescopic member 10 is located below the adjustment groove 9. When the telescopic member 10 is extended or retracted, the angle of the tilting pad 5 can be changed. (It is well known to those skilled in the art that in order to change the angle of the tilting pad 5, the adjustment groove 9 must be wide enough to prevent the adjustment groove 9 from hindering the rotation of the tilting pad 5 when the tilting pad 5 is rotated.)

[0029] The telescopic member 10 includes two strip-shaped bent plates 101, two connecting plates 102, two telescopic blocks 103, a compression spring 104, a top column 105, a bottom column 106, and a strip-shaped piezoelectric ceramic stack 7 controlled by a power driver. The two bent plates 101 are arranged in a radial direction and bent toward each other in the middle. The two connecting plates 102 are respectively fixed vertically at the two ends of the two bent plates 101. The two telescopic blocks 103 are respectively fixed on the outer side surfaces of the two connecting plates 102. The two side walls of the annular groove of the connector base 1 are provided with axially arranged telescopic grooves 107 whose cross-section is larger than the cross-section of the telescopic blocks 103. One of the telescopic blocks 103 is placed in the corresponding telescopic groove 107 and can slide radially in the telescopic groove 107. A compression spring 104 is provided between the other telescopic block 103 and the corresponding telescopic groove 107, and the other telescopic block 103 can slide radially in the corresponding telescopic groove 107. The piezoelectric ceramic stack 7 is located between the two bent plates 101 and its two ends are provided with a compression spring 104. The ends are fixedly connected to the inner side surfaces of the two connecting plates 102 respectively, the bottom surface of the top column 105 is fixed to the middle part of the outer side surface of the bent plate 101 close to the tilting pad 5, the top surface of the top column 105 presses against the top wall of the adjustment groove 9 of the tilting pad 5, the top surface of the bottom column 106 is fixed to the middle part of the outer side surface of the bent plate 101 close to the connector base 1, and the bottom surface of the bottom column 106 presses against the connector base 1. When the piezoelectric ceramic stack 7 is extended, the bending angles of the two bent plates 101 decrease but are always in a bent state (the two bent plates 101 are always in a bent state, which means that when the piezoelectric ceramic stack 7 is extended to the limit, the two bent plates 101 are still in a bent state, but the bending angles are very small. This design makes it easy for the two bent plates 101 to contract and bend along their original bending directions when the piezoelectric ceramic stack 7 is shortened, thereby achieving effective adjustment of the angle of the tilting pad 5). The compression spring 104 changes from the initial state to the compressed state, and the angle of the tilting pad 5 changes.

[0030] Working principle: when the deformation of the piezoelectric ceramic stack 7 is controlled by applying a certain voltage value through the power supply controller, when the piezoelectric ceramic stack 7 is elongated, the compression spring 104 is compressed, the bending angle of the two bending plates 101 is reduced, and the other end of the circumferential direction of the tiltable pad 5 is lifted, when the piezoelectric ceramic stack 7 is shortened, the compression spring 104 changes to the initial state, the bending angle of the two bending plates 101 is increased, and due to the supporting action of the torsion spring 6, one end of the circumferential direction of the tiltable pad 5 is lifted and the other end is lowered, so that the tiltable pad 5 and the inner wall of the workpiece deep hole produce different oil wedge gaps, thereby realizing the change of the dynamic pressure oil film pressure between the tiltable pad 5 and the inner wall of the workpiece deep hole, and balancing the radial force generated during the machining of the deep hole, thereby improving the roundness quality of the BTA tool machining deep hole.

[0031] In the scheme, the deformation of the piezoelectric ceramic stack 7 is linearly related to the voltage, so the extension and contraction amount can be precisely controlled; at the same time, due to its large free-forming range and millimeter-level precise adjustment range, precise adjustment in a large range can be realized; in addition, the angle adjustment of the tiltable pad 5 is realized by the torsion spring 6 and the telescopic mechanism, which is simple in structure, easy to realize and low in manufacturing cost; in addition, the magnification of the angle adjustment of the tiltable pad 5 can be realized by adjusting the position of the fixed rod 8, the closer the fixed rod 8 is to the telescopic mechanism, the greater the magnification of the angle adjustment of the tiltable pad 5, and the range is wide and the precise adjustment range is large.

[0032] In specific implementation, the torsion spring 6 is sleeved on the support rod 11 arranged in parallel with the axial direction of the connector base 1 and fixed at both ends of the two side walls of the annular groove 4, so that the structure is specific and standardized, thereby better positioning the torsion spring 6.

[0033] In specific implementation, the adjustment assembly is three, and the structure is specific.

[0034] In specific implementation, the three tiltable pads 5 are arranged coaxially with the connector base 1. In this specific embodiment, the central angle of the cross section of each tiltable pad 5 is 110°.

[0035] The above is only a specific embodiment of the present application, which enables those skilled in the art to understand or implement the present application. Although the foregoing embodiments are described in detail, those skilled in the art should understand that the technical solutions recorded in the foregoing embodiments can be modified, or some or all of the technical features can be replaced by equivalents; and these modifications or replacements do not make the essence of the corresponding technical solutions deviate from the scope of the technical solutions of the embodiments, and they should be covered in the protection scope of the claims.

Claims

1. A BTA tool connector based on dynamic oil film, characterized in that: The invention comprises a cylindrical connector base (1), one end of the connector base (1) is a tool connection end (2) for connecting to a BTA tool, the other end of the connector base (1) is a drill rod connection end (3) for connecting to a drill rod, an annular groove (4) is coaxially provided on the outer circumferential surface of the middle portion of the connector base (1), a plurality of adjustment components are intermittently and evenly distributed circumferentially within the annular groove (4), and a circumferential adjustment spacing is provided between two adjacent adjustment components; Each adjustment assembly includes a tilting pad (5), a torsion spring (6), a telescopic member (10), and a fixed rod (8). The tilting pad (5) is located in the annular groove (4). The cross section of the tilting pad (5) is a fan ring and the length direction of the tilting pad (5) is consistent with the axial arrangement direction of the connector base (1). The fixed rod (8) is axially arranged and rotates through the tilting pad (5). The two ends of the fixed rod (8) are respectively fixed to the two side walls of the annular groove of the connector base (1). (6) is located at one end portion in the circumferential direction of the inner wall side of the tilting pad (5), one end of the torsion spring (6) is fixedly connected to the inner wall of the tilting pad (5), and the other end of the torsion spring (6) is fixedly connected to the bottom wall of the annular groove (4) of the connector base (1), and an axially arranged adjustment groove (9) is opened at the other end portion in the circumferential direction of the inner wall of the tilting pad (5), and the telescopic member (10) is located below the adjustment groove (9) and can change the angle of the tilting pad (5) when the telescopic member (10) is extended or retracted; The telescopic member (10) comprises two strip-shaped bent plates (101), two connecting plates (102), two telescopic blocks (103), a compression spring (104), a top column (105), a bottom column (106), and a strip-shaped piezoelectric ceramic stack (7) controlled by a power driver. The two bent plates (101) are arranged in a radial direction and bent toward each other in the middle. The two connecting plates (102) are respectively fixed vertically at the two ends of the two bent plates (101). The two telescopic blocks (103) are respectively fixed on the outer side surfaces of the two connecting plates (102). The two side walls of the annular groove of the connector base (1) are provided with axially arranged telescopic grooves (107) whose cross sections are larger than the cross sections of the telescopic blocks (103). One of the telescopic blocks (103) is placed in the corresponding telescopic groove (107) and can slide radially in the telescopic groove (107). The other telescopic block (103) is located between the corresponding telescopic groove (107). A compression spring (104) is provided between the two bending plates (101) and another telescopic block (103) can slide radially in the corresponding telescopic groove (107). The piezoelectric ceramic stack (7) is located between the two bending plates (101) and its two ends are fixedly connected to the inner side surfaces of the two connecting plates (102). The bottom surface of the top column (105) is fixed to the middle of the outer side surface of the bending plate (101) close to the tilting pad (5). The top surface of the top column (105) is pressed against the top wall of the adjustment groove (9) of the tilting pad (5). The top surface of the bottom column (106) is fixed to the middle of the outer side surface of the bending plate (101) close to the connector base (1). The bottom surface of the bottom column (106) is pressed against the connector base (1). When the piezoelectric ceramic stack (7) is extended, the bending angles of the two bending plates (101) decrease but are always in a bent state. The compression spring (104) changes from an initial state to a compressed state, and the angle of the tilting pad (5) changes.

2. The BTA tool connector based on dynamic oil film according to claim 1, characterized in that: The torsion spring (6) is sleeved on a support rod (11) whose axial direction is arranged parallel to the axial direction of the connector base (1) and whose two ends are respectively fixed to the two side walls of the annular groove (4).

3. A BTA tool connector based on dynamic oil film according to claim 1 or 2, characterized in that: There are three adjustment components.

4. The BTA tool connector based on dynamic oil film according to claim 3, characterized in that: Three tilting pads (5) are coaxially arranged with the connector base (1).

5. The BTA tool connector based on dynamic oil film according to claim 4, characterized in that: The central angle of the cross section of each tilting pad (5) is 110°.

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