Reinforced lead screw pre-tensioning structure

Abstract

The utility model relates to a reinforced lead screw pre-tensioning structure which comprises a mounting seat, a lead screw pre-tensioning device and a lead screw pre-tensioning device. The tool turret base is connected to the mounting base in a sliding manner; the lead screw is mounted on the mounting seat through a bearing seat; the sliding block is in threaded connection with the lead screw, and the sliding block is fixedly connected with the tool turret base; the driving part is mounted on the mounting seat and is used for driving the lead screw to rotate; the bearing seat comprises an upper bearing seat and a lower bearing seat; the lower bearing seat comprises a first seat body and a first ball bearing, the outer ring of the first ball bearing abuts against the first seat body, and one end of the lead screw is in threaded connection with a first adjusting block; a shoulder rest is integrally formed on the mounting base and abuts against the side wall, facing the sliding block, of the first base body. The stress of the bearing seat body can be reduced, so that the problem of deformation of the bearing seat in the lead screw pre-tensioning structure is relieved.

Description

TECHNICAL FIELD

[0001] The present application relates to the field of precision machine tools, in particular to a reinforced lead screw pre-tension structure. BACKGROUND

[0002] Nowadays, with the progress of science and technology, people have higher and higher requirements for the machining accuracy of numerical control machine tools in manufacturing industry, and the lead screw transmission accuracy is an important factor affecting the machining accuracy of numerical control machine tools. In the transmission process, the lead screw generates heat due to friction or is affected by the temperature of the machining environment, which causes the lead screw to expand and stretch in the axial direction, resulting in a decrease in the machining accuracy of the machine tool.

[0003] At present, a mounting structure for reducing thermal deformation of a tool turret machine is disclosed in Chinese Patent No. CN113478273A, which comprises a mounting bracket mounted on a machine tool bed, a tool turret slidingly connected to the mounting bracket, and a driving motor mounted on the mounting bracket. The driving motor drives the tool turret to slide through a lead screw pair. The two ends of the lead screw are mounted on the rack through two bearing seats. A nut is threadedly connected to one end of the lead screw, and the nut is used to apply a pre-tension force to the lead screw through the bearing seat. In order to improve the structural strength between the bearing seat and the mounting bracket, a protrusion is provided at the bottom of the bearing seat, and the mounting bracket is provided with a groove, the protrusion and the groove are matched, and the protrusion is used to balance the tension received by the bearing seat.

[0004] However, during long-term use, the tool turret is closer to the lower bearing seat, so the lower bearing seat is subjected to the tension of the lead screw and also needs to withstand the vibration generated during the machining of the tool turret, which causes the bearing seat to easily deform, thereby affecting the pre-tensioning amount of the lead screw and causing the machining accuracy of the machine tool to decrease. Practical new type content

[0005] In order to alleviate the deformation problem of the bearing seat in the lead screw pre-tension structure, the present application provides a reinforced lead screw pre-tension structure, which adopts the following technical solutions:

[0006] The reinforced lead screw pre-tension structure comprises:

[0007] A mounting seat slidingly connected to the rack along the Y-axis;

[0008] A tool turret seat slidingly connected to the mounting seat along the X-axis, wherein the X-axis and the Y-axis are perpendicular to each other;

[0009] A lead screw mounted on the mounting seat through bearing seats provided at both ends of the lead screw;

[0010] A sliding block threadedly connected to the lead screw and fixedly connected to the tool turret seat; and

[0011] A driving member mounted on the mounting seat and used to drive the rotation of the lead screw;

[0012] The bearing seat comprises an upper bearing seat close to the driving member and a lower bearing seat located away from the driving member; the lower bearing seat comprises a first seat body and a first ball bearing mounted in the first seat body, an outer ring of the first ball bearing abuts against the first seat body at one end towards the sliding block, a first adjusting block is threadedly connected to one end of the lead screw, and the first adjusting block is extruded into an inner ring of the first ball bearing at one end towards the sliding block; the first seat body is fixedly connected to the mounting seat by bolts, and the mounting seat is integrally formed with a shoulder, and the shoulder abuts against a side wall of the first seat body towards the sliding block.

[0013] By adopting the above technical scheme, the first adjusting block is rotated to adjust the pre-tension of the lead screw and control the pre-stretching length of the lead screw. The first seat body abuts against the shoulder under the action of the tension of the lead screw, and the shoulder balances the tension of the lead screw on the first seat body. Compared with the background technology, the first seat body in the technical scheme is subjected to compressive stress, which changes the stress structure of the first seat body. First, the stress point of the first seat body is closer, so the length of the part that is deformed under stress is smaller, so the deformation amount is smaller under the same tension. Second, the stress cross-sectional area of the technical scheme is larger, so the deformation amount of the first seat body can be reduced.

[0014] Optionally, the first seat body comprises a connecting portion for mounting the first ball bearing and a mounting portion for connecting with the mounting seat, the connecting portion and the mounting portion are integrally forged and formed, and the mounting portion is provided with the connecting portion on both sides, and the connecting portion is fixedly connected with the mounting seat by a plurality of bolts.

[0015] Optionally, a tapered pin for positioning is arranged between the mounting portion and the mounting seat.

[0016] By adopting the above technical scheme, the first seat body is first positioned by the tapered pin, and then the bolts are fixed, so that the mounting position of the first seat body is more accurate, the stress of the four bolts is more uniform, and the stability of the first seat body is improved.

[0017] Optionally, one side of the mounting portion and the connecting portion towards the shoulder is flush and abuts against the shoulder.

[0018] By adopting the above technical scheme, the contact area is increased, the stress is reduced, and the deformation amount of the first seat body is reduced.

[0019] Optionally, one side of the first seat body towards the shoulder is provided with a chamfer at the bottom.

[0020] By adopting the above technical scheme, the stress concentration is reduced, and the first seat body and the shoulder can be more closely attached.

[0021] Optionally, the first ball bearing is an angular contact bearing, a fixing ring is threadedly connected to the first seat body, and the fixing ring abuts against the outer ring of the first ball bearing.

[0022] By adopting the above technical solution, the angular contact bearing has a strong axial load-bearing capacity, high precision and good rigidity.

[0023] Optionally, three first ball bearings are provided in the first seat body, wherein the front sides of two first ball bearings face the fixing ring, and the back side of the other first ball bearing contacts the fixing ring.

[0024] By adopting the above technical solution, the axial load-bearing capacity is further improved.

[0025] Optionally, the mounting seat is integrally formed with a pad, the lower surface of the first seat body is in contact with the pad, and the pad is connected to the shoulder.

[0026] By adopting the above technical solution, the mounting surface connected to the first seat body protrudes from the mounting seat, making it easier to process the mounting surface.

[0027] Optionally, the X-axis is set at an angle, and the bottom of the mounting seat is connected to the frame through two pairs of slide rails, and the two pairs of slide rails are distributed along the X-axis to form a high and low setting. The bottom of the mounting seat is fixedly connected to a sleeve mounting portion, and the sleeve mounting portion is located on the connecting line of the two pairs of slide rails.

[0028] By adopting the above technical solution, the sleeve mounting portion can be close to the turret seat, the force arm in the force system is reduced, the deformation is also reduced, and the processing accuracy is improved.

[0029] In summary, this application includes at least one of the following beneficial technical effects:

[0030] 1. Optimize the force structure and improve the load-bearing capacity. When the first seat is subjected to the tension of the screw, it can rely on the support force of the shoulder to balance the force. By optimizing the force-bearing cross-sectional area and the position of the force-bearing point, the deformation is further reduced and the stability of the overall structure is improved. The use of multiple angular contact bearings further improves the axial load-bearing capacity and ensures the stability and reliability of the structure.

[0031] 2. Improved machining accuracy and installation convenience: By optimizing the mounting base design, such as providing a backing plate and adjusting the position of the sleeve mounting portion, machining accuracy is improved. In addition, the use of a tapered pin for positioning before tightening the bolts makes the installation position of the first base more accurate and improves installation convenience. BRIEF DESCRIPTION OF THE DRAWINGS

[0032] Figure 1 It is a schematic diagram of an embodiment of the present application used to illustrate the overall structure.

[0033] Figure 2 It is a schematic diagram used to illustrate the driving structure of an embodiment of the present application.

[0034] Figure 3 is a sectional view of the lower bearing seat structure according to an embodiment of the present application.

[0035] Figure 4 is a shaft side view of the first seat body according to an embodiment of the present application.

[0036] Figure 5 is a sectional view of the upper bearing seat structure according to an embodiment of the present application.

[0037] Figure 6 is a schematic view of the force on the first seat body according to an embodiment of the present application.

[0038] Reference signs: 100, mounting seat; 101, sleeve mounting portion; 102, slide rail pair; 103, backing plate; 104, shoulder;

[0039] 200, tool turret seat;

[0040] 300, lead screw;

[0041] 400, sliding block;

[0042] 500, driving member;

[0043] 600, upper bearing seat; 610, second seat body; 620, second ball bearing; 630, second adjusting block;

[0044] 700, lower bearing seat; 710, first seat body; 711, connecting portion; 712, mounting portion; 713, conical pin; 714, force receiving surface A; 715, force receiving surface B; 720, first ball bearing; 730, fixing ring; 740, first adjusting block. DETAILED DESCRIPTION

[0045] The following will be described in detail with reference to the accompanying drawings. Figures 1-6 The present application will be described in further detail.

[0046] The present application discloses a reinforced lead screw pre-tension structure. Referring to Figure 1 , the lead screw pre-tension structure comprises:

[0047] A mounting seat 100 is slidably connected to the frame of a machine tool along a Y axis (not shown in the figure), and the Y axis is parallel to the main shaft of the machine tool in this embodiment;

[0048] A tool turret seat 200 is slidably connected to the mounting seat 100 along an X axis, wherein the X axis is perpendicular to the Y axis, and the X axis is inclined in this embodiment;

[0049] A driving structure is configured to drive the tool turret seat 200 to slide along the X axis direction.

[0050] The bottom of the mounting seat 100 is slidably connected to the rack through two pairs of slide rail pairs 102. The two pairs of slide rail pairs 102 are distributed along the X axis and are arranged at different heights. The bottom of the mounting seat 100 is integrally formed with a sleeve mounting portion 101. The sleeve mounting portion 101 is in the shape of a sleeve with an opening at the lower end, which is used to mount the sliding block of the lead screw pair that drives the mounting seat 100 to slide along the Y axis. The sleeve mounting portion 101 is located on the line connecting the two pairs of slide rail pairs 102, so that the sleeve mounting portion 101 can be close to the turret seat 200 to reduce the force arm in the force system of the mounting seat 100, thereby reducing the deformation amount of the mounting seat 100.

[0051] With reference to Figure 2 , the driving structure comprises:

[0052] a lead screw 300, the lead screw 300 being parallel to the X axis, and both ends of the lead screw 300 being provided with bearing seats, the bearing seats being mounted to the mounting seat 100;

[0053] a sliding block 400, the sliding block 400 being in the shape of a sleeve, the sliding block 400 being sleeved on the lead screw 300 and being threadedly connected with the lead screw 300, and the sliding block 400 being fixedly connected with the turret seat 200; and

[0054] a driving member 500, the driving member 500 being mounted to the mounting seat 100 and being used to drive the lead screw 300 to rotate, so as to control the sliding of the turret seat 200, the driving member 500 being a servo motor in the embodiment.

[0055] The bearing seats comprise an upper bearing seat 600 close to the driving member 500 and a lower bearing seat 700 located away from the driving member 500. The two bearing seats support the lead screw 300 and also apply a pre-tension to the lead screw 300, so as to pre-stretch the lead screw 300.

[0056] Referring to Figure 3 and Figure 4 , the lower bearing seat 700 comprises a first seat body 710 and a first ball bearing 720 mounted in the first seat body 710.

[0057] The first seat body 710 comprises a connecting portion 711 and a mounting portion 712, which are integrally forged and formed. In the embodiment, the connecting portion 711 is in the shape of a cuboid as a whole, and the upper end of the connecting portion 711 is provided with chamfered corners on both sides. The connecting portion 711 is provided with a stepped hole for mounting the first ball bearing 720.

[0058] The mounting portion 712 is in a cuboid shape and has two, which are respectively arranged on both sides of the connecting portion 711, and are fixedly connected with the mounting base 100 through a plurality of bolts. A tapered pin 713 for positioning is arranged between the mounting portion 712 and the mounting base 100. The first seat body 710 is first positioned by the tapered pin 713, and then the bolts are fixed, so that the mounting position of the first seat body 710 is more accurate, the stress of the bolts is more uniform, and the stability of the first seat body 710 is improved.

[0059] In order to facilitate the processing of the mounting surface of the mounting base 100 which is in contact with the first seat body 710, the mounting base 100 is integrally formed with a backing plate 103. The backing plate 103 is in a U shape, and the lower surface of the first seat body 710 is in contact with the backing plate 103. The mounting base 100 is integrally formed with a shoulder 104, and the backing plate 103 is connected with the shoulder 104. The mounting portion 712 and the connecting portion 711 are flush and abut against the shoulder 104 on the side facing the shoulder 104.

[0060] The first ball bearing 720 has three and is located in the stepped hole. The outer ring of the innermost first ball bearing 720 abuts against the step of the stepped hole of the first seat body 710. The first seat body 710 is threadedly connected with a fixing ring 730, and the fixing ring 730 abuts against the outer ring of the outermost first ball bearing 720.

[0061] One end of the lead screw 300 is threadedly connected with a first adjusting block 740, and the first adjusting block 740 is extruded to the inner ring of the first ball bearing 720 on the end facing the sliding block 400. The first adjusting block 740 is rotated to adjust the pre-tension of the lead screw 300 and control the pre-stretching length of the lead screw 300.

[0062] In order to improve the axial bearing capacity, the first ball bearing 720 is an angular contact bearing. The angular contact bearing has a front surface and a back surface. The front surface of the angular contact bearing is the thinner side of the outer ring, and the back surface is the thicker side of the outer ring. Among them, the front surfaces of the two first ball bearings 720 located in the deep part of the stepped hole face the fixing ring 730, and the back surface of the outer first ball bearing 720 is in contact with the fixing ring 730.

[0063] Referring to Figure 5 The upper bearing seat 600 includes a second seat body 610, which is fixedly connected to the mounting base 100 through a bolt. The second seat body 610 is also provided with a stepped hole, and two second ball bearings 620 are installed in the stepped hole of the second seat body 610. The two second ball bearings 620 are angular contact bearings and are installed in the same direction. The lead screw 300 is threadedly connected with a second adjusting block 630, and the second adjusting block 630 abuts against the inner ring of the outer second ball bearing 620. The second adjusting block 630 is rotated to adjust the pre-tension of the lead screw 300 and control the pre-stretching length of the lead screw 300.

[0064] The working principle of the embodiment is as follows:Figure 6 The first seat body 710 is abutted against the shoulder 104 under the pulling force of the screw rod 300, and the shoulder 104 supports the pulling force of the screw rod 300 on the first seat body 710. Compared with the prior art, the first seat body 710 is subjected to compressive stress, and the force structure of the first seat body 710 is changed.

[0065] Firstly, the two force receiving surfaces of the first seat body 710 are closer. The force receiving surface A 714 is the force receiving surface of the pressure applied by the first ball bearing 720 on the first seat body 710, and the force receiving surface B 715 is the force receiving surface of the support force applied by the shoulder 104 on the first seat body 710. The distance between the force receiving surface A 714 and the force receiving surface B 715 is smaller. When the deformed part has a smaller length, the deformation is smaller under the same pulling force.

[0066] Secondly, the force receiving cross-sectional area is larger. Because the two forces are not on the same line, shear force is generated, and the shear stress generated by the shear force is transversely through the first seat body 710. Therefore, compared with the prior art, the cross-sectional area of the shear stress in the present application is larger, and the shear stress is smaller, so that the deformation is not easy to occur.

[0067] The above are preferred embodiments of the present application, and are not intended to limit the protection scope of the present application. Therefore, any equivalent changes made on the basis of the structure, shape and principle of the present application should be covered within the protection scope of the present application.

Claims

1. A reinforced lead screw pre-tension structure, comprising: a mounting seat (100) slidably connected to a rack along a Y axis; a tool turret seat (200) slidably connected to the mounting seat (100) along an X axis, wherein the X axis is perpendicular to the Y axis; a lead screw (300) mounted to the mounting seat (100) through bearing seats arranged at both ends; a sliding block (400) threadedly connected to the lead screw (300) and fixedly connected to the tool turret seat (200); and a driving member (500) mounted to the mounting seat (100) and configured to drive the lead screw (300) to rotate; characterized in that the bearing seats include an upper bearing seat (600) close to the driving member (500) and a lower bearing seat (700) away from the driving member (500); the lower bearing seat (700) includes a first seat body (710) and a first ball bearing (720) mounted in the first seat body (710), an outer ring of the first ball bearing (720) abuts against the first seat body (710) at an end facing the sliding block (400), and a first adjusting block (740) is threadedly connected to an end of the lead screw (300) and pressed against an inner ring of the first ball bearing (720) at an end facing the sliding block (400); the first seat body (710) is fixedly connected to the mounting seat (100) by bolts, and the mounting seat (100) is integrally formed with a shoulder (104) abutting against a side wall of the first seat body (710) facing the sliding block (400).

2. The reinforced lead screw pre-tension structure according to claim 1, characterized by: The first seat body (710) includes a connecting portion (711) for mounting the first ball bearing (720) and a mounting portion (712) for connection with the mounting seat (100), and the connecting portion (711) and the mounting portion (712) are integrally forged and formed, the mounting portion (712) is provided with the connecting portion (711) on both sides, and the connecting portion (711) is fixedly connected to the mounting seat (100) by bolts.

3. The reinforced lead screw pre-tension structure according to claim 2, characterized by: A taper pin (713) for positioning is arranged between the mounting portion (712) and the mounting seat (100).

4. The reinforced lead screw pre-tension structure according to claim 2, wherein: The mounting portion (712) and the connecting portion (711) are flush and abut against the shoulder (104) on a side facing the shoulder (104).

5. The reinforced lead screw pre-tension structure of claim 2, wherein: A chamfer is arranged at a bottom of a side of the first seat body (710) facing the shoulder (104).

6. The reinforced lead screw pre-load structure of claim 1, wherein: The first ball bearing (720) is an angular contact bearing, and a fixing ring (730) is threadedly connected to the first seat body (710) and abuts against an outer ring of the first ball bearing (720).

7. The reinforced lead screw pre-tension structure according to claim 6, characterized by: The first ball bearing (720) in the first seat body (710) is provided with three, a front surface of two of the first ball bearings (720) faces the fixing ring (730), and a back surface of the other first ball bearing (720) contacts the fixing ring (730).

8. The reinforced lead screw pre-load structure of claim 1, wherein: The mounting seat (100) is integrally formed with a backing plate (103), the lower surface of the first seat body (710) is in contact with the backing plate (103), and the backing plate (103) is connected with a shoulder (104).

9. The reinforced lead screw pre-load structure of claim 1, wherein: The X axis is arranged in an inclined manner, the bottom of the mounting seat (100) is connected with a rack through two pairs of slide rail pairs (102), the two pairs of slide rail pairs (102) are distributed along the X axis to form a high-low arrangement, and the bottom of the mounting seat (100) is fixedly connected with a sleeve mounting portion (101); the sleeve mounting portion (101) is located on the connecting line of the two pairs of slide rail pairs (102).

Images