Ball screw pair external S-shaped internal circulation reverser assembly and installation method

Abstract

The present invention belongs to the technical field of ball screws, and relates to an S-shaped internal circulation reverser assembly and installation method for a ball screw pair, comprising a screw, a nut, and a plurality of balls, wherein the nut is externally embedded on the screw, and the plurality of balls are arranged in a spiral raceway formed between the outer surface of the screw and the inner surface of the nut, and is characterized in that: a plurality of reverser mounting holes are axially arranged on the nut, and a reverser is respectively installed in each of the reverser mounting holes, and the two ends of the reverser are respectively connected to two adjacent spiral raceways to form a lead of ball circulation rolling; the positioning part of the reverser is matched with the limiting part arranged in the reverser mounting hole to realize the limiting setting of the reverser; the circumferential surface of the nut is provided with a sleeve by interference fit to radially limit the reverser. The present invention can reduce the difficulty of assembling the reverser, improve the structural strength and processing efficiency of the nut, prevent grease leakage, and reduce the overall noise of the ball screw pair.

Description

Technical Field

[0001] The invention belongs to the technical field of ball screws, and relates to an S-shaped internal circulation reverser component mounted outside a ball screw pair and an installation method. Background Art

[0002] The ball screw pair is a common transmission device used for the conversion between rotary motion and linear motion, or for positioning. It consists of a screw and nut with a spiral raceway, multiple balls, and a reverser. The rolling of the balls between the screw spiral raceway and the nut spiral raceway enables efficient transmission and positioning. The ball screw pair has the characteristics of high precision, large load capacity, low friction, and high efficiency. Therefore, it is widely used in mechanical equipment, such as CNC machine tools, automated production lines, aerospace equipment, and automobiles.

[0003] The reverser in the ball screw pair is a device that realizes the circular motion of the balls in the spiral raceway. The quality of its working performance will directly affect the transmission quality. At present, the reverser has the problems of high noise, poor durability, and difficult installation and maintenance. It is necessary to design a reverser that is easy to assemble and has good smoothness. Summary of the invention

[0004] In view of the above problems, the present invention provides an S-shaped internal circulation reverser assembly externally mounted on a ball screw pair. The reverser assembly is easy to assemble and has good smoothness during use.

[0005] According to the technical solution of the present invention: a ball screw pair externally mounted S-shaped internal circulation reverser assembly, comprising a screw rod, a nut, and a plurality of balls, wherein the nut is externally embedded on the screw rod, and the plurality of balls are arranged in a spiral raceway formed between the outer surface of the screw rod and the inner surface of the nut, characterized in that: a plurality of reverser mounting holes are axially arranged on the nut, a reverser is respectively installed in each of the reverser mounting holes, and the two ends of the reverser are respectively connected to two adjacent spiral raceways, forming a lead for the ball circulation rolling;

[0006] The positioning portion of the reverser is matched with the limiting portion of the reverser mounting hole to realize the limiting setting of the reverser;

[0007] The circumferential surface of the nut is interference-fitted with a sleeve to radially limit the reverser.

[0008] As a further improvement of the present invention, the plurality of reverser mounting holes are evenly distributed along the circumferential direction of the nut.

[0009] As a further improvement of the present invention, the spiral raceway includes a screw raceway extending spirally from one axial end of the screw outer surface to the other end and a plurality of nut raceways evenly distributed on the inner wall of the nut, and the two ends of the reverser are respectively connected to the head and tail ends of the nut raceway.

[0010] As a further improvement of the present invention, the curvature of the outer surface of the deflector is consistent with the outer circle of the nut, and a ball return track is arranged on the inner surface of the deflector so that the balls can pass over the top of the spiral track and return to the initial position of the spiral track.

[0011] As a further improvement of the present invention, the ball return track is deep in the middle and shallow at both ends.

[0012] As a further improvement of the present invention, the shape of the ball return track is determined by a fifth-order parabola, and the expression of the fifth-order parabola is:

[0013] ;

[0014] in:

[0015] ;

[0016] In the formula L is the lead of the helical pair (mm), λ is the ball helix angle, x F On the bead curve F The coordinates of the point, d 0 is the center circle diameter of the ball in the spiral pair (mm), , .

[0017] As a further improvement of the present invention, the positioning portion of the reverser is constructed as two semicircular boss structures, and the two semicircular boss structures are respectively arranged on both sides of the reverser;

[0018] The limiting portion of the reverser mounting hole is constructed as two limiting grooves, which are arranged on the inner wall of the reverser mounting hole and extend to the outer surface of the nut;

[0019] The semicircular boss structure of the reverser is arranged in the limiting groove.

[0020] As a further improvement of the present invention, a circle of ribs is protruding from the top edge of the reverser. After the reverser is installed on the nut, the upper end of the ribs is flush with the outer surface of the nut, and the area surrounded by the ribs constitutes a groove.

[0021] As a further improvement of the present invention, the reverser is S-shaped.

[0022] The present invention also provides a method for installing an S-shaped internal circulation reverser assembly mounted on a ball screw pair, the method comprising: threading a nut onto a screw rod, and arranging a plurality of balls in a spiral raceway formed between an outer surface of the screw rod and an inner surface of the nut;

[0023] A plurality of reverser mounting holes are arranged axially on the nut, and the plurality of reverser mounting holes are evenly arranged along the circumferential direction of the nut, and a reverser is respectively installed in each reverser mounting hole, and two ends of the reverser are respectively connected to two adjacent spiral raceways to form a lead for the ball to circulate and roll;

[0024] The sleeve is interference fit on the circumferential surface of the nut to radially limit the reverser.

[0025] The technical effects of the present invention are: 1) The deflector is installed inward from the outer surface of the nut, which greatly reduces the difficulty of assembly. 2) The deflector is S-shaped, which reduces the impact of the ball when entering and exiting the deflector. 3) The nut raceway presents a discontinuous characteristic and has a higher degree of integration. 4) The wall thickness between the deflector mounting hole and the raceway is thicker and the structural strength is higher. 5) Less material is turned and milled out of the nut raceway during processing, the processing time is shorter, and the processing efficiency is higher. 6) A sleeve is installed on the outer surface of the nut, and the nut has a closed shape, which can prevent grease leakage, and can isolate noise, thereby improving the overall noise value of the ball screw pair. BRIEF DESCRIPTION OF THE DRAWINGS

[0026] Figure 1 It is a structural schematic diagram of the present invention.

[0027] Figure 2 It is the front view of the reverser in the present invention.

[0028] Figure 3 for Figure 2 Left view of .

[0029] Figure 4 for Figure 2 AA section view.

[0030] Figure 5 It is an axial end view of the nut in the present invention.

[0031] Figure 6 for Figure 5 BB section view.

[0032] Figure 7 for Figure 6 Top view of the .

[0033] Figure 8 It is a schematic diagram of the nut raceway crest structure of the present invention.

[0034] Fig. 9 It is a schematic diagram of the existing reverser nut raceway tooth top structure. DETAILED DESCRIPTION

[0035] The specific implementation of the present invention will be further described below in conjunction with the accompanying drawings.

[0036] Figure 1-9 The invention comprises a nut 1, a reverser mounting hole 2, a screw rod 3, a reverser 4, a sleeve 5, a semicircular boss structure 6, a groove 7, a ball return raceway 8, a limit groove 9, and a minimum dimension δ of the nut raceway tooth top of the invention. 1 、The minimum size of the existing reverser nut raceway tooth top δ 2 wait.

[0037] like Figure 1-9 As shown, the present invention is an S-shaped internal circulation reverser assembly externally mounted on a ball screw pair, comprising a screw rod 3, a nut 1, and a plurality of balls, wherein the nut 1 is externally embedded on the screw rod 3, and the plurality of balls are arranged in a spiral raceway formed between the outer surface of the screw rod 3 and the inner surface of the nut 1, and a plurality of reverser mounting holes 2 are axially arranged on the nut 1, and a reverser 4 is respectively installed in each of the reverser mounting holes 2, and the two ends of the reverser 4 are respectively connected to two adjacent spiral raceways to constitute a lead for the ball circulation rolling.

[0038] The positioning portion of the reverser 4 is matched with the limiting portion of the reverser mounting hole 2 to realize the limiting setting of the reverser 4 and ensure that the reverser 4 can be reliably and accurately positioned in the reverser mounting hole 2.

[0039] The sleeve 5 is provided on the circumferential surface of the screw rod 3 in an interference fit to limit the radial position of the reverser 4. The sleeve 5 can reduce the overflow of grease from the hole and can isolate noise.

[0040] Furthermore, a plurality of reverser mounting holes 2 are evenly distributed along the circumferential direction of the nut 1 to ensure that the nut 1 is subjected to uniform force.

[0041] like Figure 1 , 6 As shown, the spiral raceway includes a screw raceway extending from one end of the outer axial surface of the screw 3 to the other end in a spiral manner and a multi-channel nut raceway evenly arranged on the inner wall of the nut 1, and the two ends of the deflector 4 are respectively connected to the head and tail ends of the nut raceway. That is, the nut raceway is set as a multi-channel discontinuous structure, and two adjacent nut raceways are connected by the deflector 4. Since the nut raceway is set as a discontinuous structure, the processing surface is reduced, the processing efficiency is improved, and the structural strength and integration of the nut 1 are improved.

[0042] The curvature of the outer surface of the deflector 4 is consistent with the outer circle of the nut 1, and a ball return track 8 is arranged on the inner surface of the deflector 4 so that the balls can pass over the top of the spiral track and return to the initial position of the spiral track.

[0043] The ball return raceway 8 is deep in the middle and shallow at both ends, which can force the balls to pass over the top of the screw raceway teeth and return to the initial raceway.

[0044] The shape of the ball return raceway 8 is determined by a quintic parabola ball return curve, and the expression of the quintic parabola is:

[0045] ;

[0046] in:

[0047] ;

[0048] In the formula L is the lead of the helical pair (mm), λ is the ball helix angle, x F On the bead curve F The coordinates of the point, d 0 is the center circle diameter of the ball in the spiral pair (mm), , .

[0049] Furthermore, it is determined from the expression of the quintic parabola that the inverter 4 is S-shaped.

[0050] The positioning portion of the reverser 4 is constructed as two semicircular boss structures 6 , and the two semicircular boss structures 6 are respectively arranged on both sides of the reverser 4 .

[0051] The limiting portion of the reverser mounting hole 2 is configured as two limiting grooves 9 , which are arranged on the inner wall of the reverser mounting hole 2 and extend to the outer surface of the nut 1 .

[0052] The semicircular boss structure 6 of the reverser 4 is arranged in the limiting groove 9 .

[0053] A circle of ribs is protruding from the edge of the top surface of the reverser 4. After the reverser 4 is installed on the nut 1, the upper end of the ribs is flush with the outer surface of the nut 1, and the area surrounded by the ribs constitutes a groove 7. When in use, when the reverser 4 is embedded in the nut 1, the depth of the groove 7 is lower than the outer surface of the nut 1, which facilitates the removal and placement of the reverser 4.

[0054] like Figure 1-9 As shown, during assembly, the present invention installs the S-shaped deflector 4 from the outside to the inside in the deflector mounting hole 2 of the nut 1, and then the sleeve 5 is tightly sleeved on the nut 1 to cover all the deflector mounting holes 2 on the surface of the nut 1, so as to prevent the deflector 4 from falling off during the operation of the ball screw pair. This assembly method can greatly reduce the difficulty of assembly.

[0055] like Figure 8 , 9 As shown, compared with the nut of the existing reverser, the curvature of the reverser mounting hole 2 at both ends of the present invention is closer to the nut raceway, and the degree of intrusion of the reverser mounting hole 2 at both ends into the raceway tooth top is smaller, that is, δ 1 Greater than δ 2Therefore, compared with the existing reverser structure, the reverser 4 reduces the stress concentration phenomenon of the nut raceway, making the structural strength of the nut better.

[0056] The present invention also provides a method for installing an S-shaped internal circulation reverser assembly mounted on a ball screw pair, the method comprising: threading a nut 1 onto a screw rod 3, and arranging a plurality of balls in a spiral raceway formed between an outer surface of the screw rod 3 and an inner surface of the nut 1;

[0057] A plurality of deflector mounting holes 2 are arranged axially on the nut 1, and the plurality of deflector mounting holes 2 are evenly distributed along the circumferential direction of the nut 1, and a deflector 4 is respectively installed in each deflector mounting hole 2, and the two ends of the deflector 4 are respectively connected to two adjacent spiral raceways to form a lead for the ball to circulate and roll;

[0058] The sleeve 5 is interference-fitted with the circumferential surface of the nut 1 to radially limit the reverser 4. The above method realizes the installation of the reverser 4 from the outside to the inside.

[0059] Finally, it should be noted that the above specific implementation methods are only used to illustrate the technical solution of the present invention rather than to limit it. Although the present invention has been described in detail with reference to examples, those skilled in the art should understand that the technical solution of the present invention can be modified or replaced by equivalents without departing from the spirit and scope of the technical solution of the present invention, which should be included in the scope of the claims of the present invention.

Claims

1. A ball screw pair externally mounted S-shaped internal circulation reverser assembly, comprising a screw rod (3), a nut (1), and a plurality of balls, wherein the nut (1) is externally embedded on the screw rod (3), and the plurality of balls are arranged in a spiral raceway formed between the outer surface of the screw rod (3) and the inner surface of the nut (1), characterized in that: A plurality of deflector mounting holes (2) are arranged in the axial direction on the nut (1), a deflector (4) is respectively installed in each of the deflector mounting holes (2), and two ends of the deflector (4) are respectively connected to two adjacent spiral raceways to form a lead for the ball to circulate and roll; The positioning portion of the reverser (4) is arranged in cooperation with the limiting portion of the reverser mounting hole (2) to achieve the limiting setting of the reverser (4); The circumferential surface of the nut (1) is provided with a sleeve (5) in an interference fit to radially limit the reverser (4); the sleeve (5) is tightly sleeved on the nut (1) to cover all reverser mounting holes (2) on the surface of the nut (1); The curvature of the outer surface of the deflector (4) is consistent with the outer circle of the nut (1), and a ball return track (8) is provided on the inner surface of the deflector (4) so ​​that the balls pass over the top of the spiral track and return to the initial position of the spiral track; The ball return track (8) is deep in the middle and shallow at both ends; The curvature of the reverser mounting hole (2) at both ends thereof is close to the nut raceway; The spiral raceway comprises a screw raceway extending spirally from one axial end of the outer surface of the screw (3) to the other end and a plurality of nut raceways evenly arranged on the inner wall of the nut (1), the nut raceway being arranged as a plurality of discontinuous structures, and the two ends of the deflector (4) being respectively connected to the head and tail ends of the nut raceway; The reverser (4) is S-shaped; The positioning portion of the reverser (4) is constructed as two semicircular boss structures (6), and the two semicircular boss structures (6) are respectively arranged on both sides of the reverser (4); The limiting portion of the reverser mounting hole (2) is constructed as two limiting grooves (9), wherein the limiting grooves (9) are arranged on the inner wall of the reverser mounting hole (2) and extend to the outer surface of the nut (1); The semicircular boss structure (6) of the reverser (4) is arranged in the limiting groove (9); The above structure is installed by the following method: a nut (1) is threadedly connected to a screw rod (3), and a plurality of balls are arranged in a spiral raceway formed between an outer surface of the screw rod (3) and an inner surface of the nut (1); A plurality of deflector mounting holes (2) are arranged in the axial direction of the nut (1), and the plurality of deflector mounting holes (2) are evenly distributed in the circumferential direction of the nut (1); a deflector (4) is respectively installed in each deflector mounting hole (2), and the two ends of the deflector (4) are respectively connected to two adjacent spiral raceways to form a lead for the ball to circulate and roll; The sleeve (5) is interference-fitted onto the circumferential surface of the nut (1) to radially limit the deflector (4).

2. The ball screw pair externally mounted S-shaped internal circulation reverser assembly according to claim 1, characterized in that: The plurality of reverser mounting holes (2) are evenly distributed along the circumferential direction of the nut (1).

3. The ball screw pair external S-shaped internal circulation reverser assembly according to claim 1, characterized in that: The shape of the ball return raceway (8) is determined by a fifth-order parabola, and the expression of the fifth-order parabola is: ， in: ， In the formula L is the lead of the helical pair (mm), λ is the ball helix angle, x F On the bead curve F The coordinates of the point, d 0 is the center circle diameter of the ball in the spiral pair (mm); , .

4. The ball screw pair externally mounted S-shaped internal circulation reverser assembly according to claim 1, characterized in that: A circle of ribs is protruding from the edge of the top surface of the deflector (4). After the deflector (4) is mounted on the nut (1), the upper end of the ribs is flush with the outer surface of the nut (1), and the area surrounded by the ribs forms a groove (7).

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