Rapid roller assembling tool and assembling method thereof

Abstract

According to the rapid roller assembling tool and the assembling method thereof, the assembling sequence of the rollers and a retainer is adjusted by changing the retainer structure of a planetary roller lead screw, and the purposes of reducing the assembling difficulty of the planetary roller lead screw, improving the assembling efficiency and reducing the requirement for assembling personnel are achieved; the invention further provides a structural design method of the open limiting retainer matched with the rapid roller assembly tool, and the structural design of the open limiting retainer under the limitation of small size and low material strength is completed by combining a contour shape determination method of feature points and a finite element simulation analysis technology. The roller lead screw assembling efficiency can be greatly improved, and the roller lead screw assembling device is particularly suitable for assembling of a roller lead screw transmission mechanism with the limited operation space. And by combining a contour shape determination method of the feature points and a finite element simulation analysis technology, the structural design of the opening limiting retainer under the limitation of small size and low material strength is completed.

Description

Technical Field

[0001] The invention relates to the technical field of planetary roller screws, and in particular to a roller quick assembly tool and a method thereof. Background Art

[0002] Planetary roller screw is a mechanical transmission device that converts rotational motion into linear motion through threaded engagement. Compared with ball screw, planetary roller screw has higher impact resistance, stronger load-bearing capacity and longer life. Planetary roller screw is generally widely used in high-load, high-precision and high-speed systems, such as welding robots, fifth-generation fighter F-35B, machine tool feeding system, vehicle erection system and other facilities.

[0003] An existing planetary roller screw closed cage structure and roller assembly method thereof, after assembling one cage, assemble the roller first, and then assemble the other cage and the inner gear ring. This assembly method has low efficiency, cumbersome assembly operation process, and is greatly affected by human factors, which reduces the production efficiency of the planetary roller screw and increases the difficulty of assembling the planetary roller screw. Therefore, it is quite necessary to propose a planetary roller screw roller quick assembly method and an open limit cage structure design method. Summary of the invention

[0004] In order to overcome the shortcomings of the prior art, the present invention provides a roller quick assembly tool and an assembly method thereof. The purpose of the present invention is to provide a roller quick assembly tool, which adjusts the assembly sequence of the roller and the cage by changing the cage structure of the planetary roller screw, thereby reducing the assembly difficulty of the planetary roller screw, improving the assembly efficiency and reducing the requirements for the assembly personnel; the present invention also proposes a method for designing an opening limit cage structure matched with the roller quick assembly tool, combining the contour shape determination method of the characteristic point with the finite element simulation analysis technology, and completing the design of the opening limit cage structure under the constraints of small size and low material strength.

[0005] The quick assembly tool is suitable for the assembly of roller screw transmission mechanisms such as standard planetary roller screws, reverse planetary roller screws and differential planetary roller screws. The roller quick assembly tool includes an open limit retainer and an auxiliary base, wherein the open limit retainer includes a retainer base and an open limit structure. When assembling a traditional roller screw, the two retainers are installed before and after the roller is assembled, respectively. There are problems such as difficulty in adjusting the position of the roller, lack of effective support for the roller during assembly, and difficulty in matching multiple rollers with the retainer at the same time, which seriously restricts the assembly efficiency of the roller screw. The present invention proposes a quick assembly method that first completes the assembly of the two retainers, uses the auxiliary base and the two retainers to achieve stable support for the rollers, and then performs roller installation. Compared with traditional assembly methods and structures, the present invention can greatly improve the assembly efficiency of the roller screw, and is particularly suitable for the assembly of roller screw transmission mechanisms with limited operating space. The present invention also includes a structural design method for an opening limit retainer that is compatible with a roller quick assembly tool, which combines a contour shape determination method of characteristic points with finite element simulation analysis technology to complete the structural design of the opening limit retainer under the constraints of small size and low material strength.

[0006] The technical solution adopted by the present invention to solve its technical problem is:

[0007] A roller quick assembly tool comprises an open limit retainer, an auxiliary base and a roller. The open limit retainer is placed on the auxiliary base. The auxiliary base is horizontally placed at the bottom of the open limit retainer in the assembly body. There are two open limit retainers. The roller is vertically assembled in the open limit retainer. The outer periphery of the open limit retainer is a nut. At the upper end of the roller, an inner gear ring is provided between the roller and the inner diameter of the nut.

[0008] Preferably, in the roller quick assembly tooling, the opening limit retainer includes a retainer base and an opening limit structure, the retainer base is an annular structure, the inner diameter of the retainer base is provided with a plurality of evenly distributed opening limit structures, the opening limit structure is a symmetrical structure, each opening limit structure includes a symmetrical unloading groove structure, a through hole structure, a protrusion structure and an end portion, two groups of unloading groove structures, through hole structures, protrusion structures and the end portion form a buckle, and the cylinders at the upper and lower ends of the roller are inserted into the through hole structure from the protrusion structure through the end portion.

[0009] Preferably, in the roller quick assembly tooling, the auxiliary base includes an auxiliary base base step, a retaining frame support step and a radial positioning ring, the auxiliary base base step is a cylindrical base at the inner bottom of the auxiliary base; the retaining frame support step is a disc-shaped support step arranged on the upper layer of the auxiliary base base step; the radial positioning ring is a circular ring arranged on the upper layer of the retaining frame support step.

[0010] Preferably, in the roller quick assembly tool, a circular through hole is provided at the center of the auxiliary base, the circular through hole is larger than the major diameter of the screw, and the auxiliary base base step, the retaining frame support step, and the radial positioning ring are coaxial with the circular through hole.

[0011] Preferably, in the roller quick assembly tool, the diameter of the auxiliary base step is larger than the diameter of the outer large end of the nut.

[0012] Preferably, in the roller quick assembly tool, the diameter of the cage support step is equal to the outer diameter of the opening limit cage.

[0013] Preferably, in the roller quick assembly tool, the diameter of the radial positioning ring is smaller than the inner diameter of the opening limit retaining frame.

[0014] The present invention also provides an assembly method for a roller quick assembly tool, comprising the following steps:

[0015] Step 1, take the auxiliary base, place the auxiliary base horizontally, place an opening limit retainer horizontally on the auxiliary base, then push the smooth inner groove of the inner gear ring horizontally downward to insert the opening limit retainer into the smooth inner groove of the inner gear ring, and then push the large end of the nut horizontally downward to insert the inner gear ring into the smooth inner groove of the nut;

[0016] Step 2, take the inner gear ring, turn the smooth inner groove of the inner gear ring upward horizontally and insert the inner gear ring into the smooth inner groove of the small end of the nut, and then insert an open limit retainer into the smooth inner groove of the inner gear ring;

[0017] Step 3, take a roller, place the roller vertically along the axis, and insert the cylinders at the upper and lower ends of the roller into the opening limit structure in the opening limit cage respectively, and repeat the installation of the roller until all the rollers are installed at the corresponding positions of the rollers, then remove the auxiliary base and assemble the lead screw;

[0018] The present invention also provides a method for designing an opening limit retainer of a roller quick assembly tool, comprising the steps of:

[0019] Step 1, determining the geometric features of the retainer base and the geometric features of the opening limit structure;

[0020] The inner and outer contours of the cage base are concentric circles; the opening limit structure is arranged in an axis-circling array inside the cage base; the cage base and the opening limit structure have the same axial thickness;

[0021] The geometric characteristic points of the axisymmetric shape of the opening limit structure are P1, P2, P3, P4, P5, P6, P7,

[0022] P8, P9; The opening limit structure has a geometric contour shape of a curved segment, wherein the curved segment Represents the contour shape of the unloading chute structure, the curve segment With curve segment Represents the outline shape of the through-hole structure, a broken line segment With straight line segment Represents the contour shape of the raised structure, straight line segment Represents the contour shape of the end part; curve segment On the inner circle of the cage base, the straight line segment With curve segment Tangent;

[0023] The characteristic points P2, P3, P4, P5, P6, P7, and P9 have rounded corners;

[0024] Step 2: Determine the characteristic parameter dimensions H, R of the cage base and the opening limit structure a ,R b ,R c ,R d , R1, R2, h1, h2, h3, h4, L1, L2; the axial thickness of the retaining frame base and the opening limiting structure is H;

[0025] The coordinate system origin O of the basic outline shape of the opening limiting structure is located on the curve segment on the symmetry axis of the opening limiting structure. The center of the circle;

[0026] The common center coordinate C1 of the inner circle and the outer circle of the retaining frame base is X c , Y c ; where X c =0, Y c =-R c ; The inner circle diameter is R a , the outer diameter is R b , the number of arrays of the opening limiting structure around the axis is k;

[0027] Curve Segment The radius of the arc is R a , the coordinates of the center of the circle are C1; the coordinates of point P1 are X1, Y1; where X1=0, Y1=R a -R c ;

[0028] The coordinates of point P2 are X2, Y2; where X2 = h1,

[0029] Curve Segment The radius of the arc is R1, the coordinates of the center of the circle are O, and the coordinates of point P3 are X3, Y3; where X3 = h1,

[0030] The coordinates of point P4 are X4, Y4; where X4 = h2, h2 is the radius of the cylinders at the upper and lower ends of the roller;

[0031] The coordinates of point P5 are X5, Y5; where X5 = h3, Y5 = -h4;

[0032] Curve Segment The radius of the arc is R d , the coordinates of the center of the circle are C1, and the coordinates of point P6 are X6, Y6; where X6 = h2,

[0033] The coordinates of point P7 are X7, Y7;

[0034]

[0035] Curve Segment The arc radius is R2, the center coordinates are O, and the coordinates of point P8 are X8, Y8; where X8 =

[0036]

[0037] The coordinates of point P9 are X9, Y9;

[0038] The fillet radius at P2, P3, P6, P7, and P9 is L1, and the fillet radius at P4 and P5 is L2;

[0039] Step 3, perform finite element assembly analysis;

[0040] Finite element assembly analysis is based on the target requirement of the roller being inserted into the open limit cage in the radial direction. The finite element analysis software ABAQUS is used to perform finite element simulation analysis on the assembly process of the roller upper and lower cylinders being inserted into the open limit structure in the radial direction.

[0041] Step 4, determine whether the stress results obtained by the finite element assembly analysis meet the design requirements. The design requirements are that the maximum Mises stress in the finite element assembly analysis results does not exceed the yield limit of the material, and the maximum node reaction force in the finite element assembly analysis process does not exceed 30N. When the stress results obtained by the finite element assembly analysis meet the design requirements, the opening limit retainer structure design is formed; if the stress results obtained by the finite element assembly analysis do not meet the requirements, repeat steps 2-3 until the stress results obtained by the finite element assembly analysis meet the design requirements; at this point, the structural design of the opening limit retainer is completed.

[0042] The beneficial effect of the present invention is that the standard closed cage structure is replaced by an open limit cage structure, and combined with a roller quick assembly tool, the assembly difficulty is reduced by changing the parts assembly sequence of the planetary roller screw; the present invention also proposes an open limit cage structure design method that is compatible with the roller quick assembly tool, and solves the open limit cage structure design problem under small size and low material strength based on the contour shape determination method of the characteristic points and the finite element simulation analysis technology. BRIEF DESCRIPTION OF THE DRAWINGS

[0043] Figure 1 It is a structural schematic diagram of the roller quick assembly method provided by the present invention;

[0044] Figure 2 It is a schematic diagram of the structure of the opening limit retainer provided by the present invention;

[0045] Figure 3 It is a schematic diagram of the structure of the auxiliary base provided by the present invention;

[0046] Figure 4 It is a schematic diagram of the roller structure provided by the present invention;

[0047] Figure 5 It is a plan view of the opening limiting structure in the opening limiting retainer provided by the present invention;

[0048] Figure 6 It is a schematic diagram of the structural design feature points of the opening limit retainer provided by the present invention;

[0049] Figure 7 It is a schematic diagram of the characteristic dimensions of the structure design of the opening limit retainer provided by the present invention;

[0050] Figure 8 It is a flow chart of the design method of the opening limit structure cage provided by the present invention;

[0051] Fig. 9 It is a Mises stress result cloud diagram of an embodiment of the present application;

[0052] Fig.10 is a node reaction process diagram of an embodiment of the present application;

[0053] Among them, 1 is an open limit retainer, 2 is an auxiliary base, 3 is a roller, 4 is a nut, 5 is an inner gear ring, 1-1 is a retainer base, 1-2 is an open limit structure, 2-1 is an auxiliary base base step, 2-2 is a retainer support step, 2-3 is a radial positioning ring, 3-1 is the upper and lower cylinders of the roller, 1-2a is an unloading groove structure, 1-2b is a through hole structure, 1-2c is a protrusion structure, and 1-2d is the end portion. DETAILED DESCRIPTION

[0054] The present invention is further described below in conjunction with the accompanying drawings and embodiments.

[0055] The present embodiment is a roller quick assembly method and a matching opening limit retainer structure design method. The technical solution of the present application will be described in detail below with reference to the accompanying drawings and in combination with the embodiments.

[0056] The present embodiment provides a roller quick assembly tool, including an open limit retainer, the open limit retainer having two, the open limit retainer being used to fix vertical rollers; an auxiliary base, the auxiliary base being horizontally placed at the bottom of the open limit retainer in the assembly body, the auxiliary base being used to assist the roller in being assembled on the open limit retainer.

[0057] In this embodiment, the opening limit retainer comprises a retainer base and an opening limit structure. The retainer base is an annular structure on the inner and outer peripheries of the opening limit retainer, which is used to support the opening limit retainer; the opening limit structure comprises an unloading groove structure, a through hole structure, a protrusion structure and an end portion, and the upper and lower cylinders of the roller are inserted into the through hole structure from the protrusion structure through the end portion.

[0058] In this embodiment, the auxiliary base comprises an auxiliary base step, a retainer support step, and a radial positioning ring. The auxiliary base step is a cylindrical base at the bottom of the auxiliary base; the retainer support step is a disc-shaped support step arranged on the upper layer of the auxiliary base step; and the radial positioning ring is a circular ring arranged on the upper layer of the retainer support step.

[0059] In this embodiment, the auxiliary base is provided with a circular through hole inside, the circular through hole is larger than the major diameter of the screw. The auxiliary base base step, the retainer support step, and the radial positioning ring are coaxial with the internal circular through hole, the diameter of which is larger than the major diameter of the screw.

[0060] In this embodiment, the base step diameter of the auxiliary base is larger than the outer large end diameter of the nut.

[0061] In this embodiment, the diameter of the retainer support step is equal to the outer diameter of the opening limiting retainer.

[0062] In this embodiment, the diameter of the radial positioning ring is smaller than the inner diameter of the opening limiting retainer.

[0063] The assembly method of the roller quick assembly tool in this embodiment has the following specific steps:

[0064] Step 1, take the auxiliary base, place the auxiliary base horizontally, place an opening limit retainer horizontally on the auxiliary base, then put the smooth inner groove of the inner gear ring horizontally downward to make the opening limit retainer insert into the smooth inner groove of the inner gear ring, and then put the large end of the nut horizontally downward to make the inner gear ring insert into the smooth inner groove of the nut;

[0065] Step 2, take the inner gear ring, turn the smooth inner groove of the inner gear ring upward horizontally and insert the inner gear ring into the smooth inner groove of the small end of the nut, and then insert an open limit retainer into the smooth inner groove of the inner gear ring;

[0066] Step 3, take a roller, place the roller vertically along the axis, and insert the upper and lower cylinders of the roller into the opening limit structure in the opening limit holder respectively, repeat the above steps until all rollers are installed at the corresponding positions, then remove the auxiliary base and assemble the lead screw;

[0067] This embodiment provides a design method for an opening limit retainer, comprising the steps of:

[0068] Step 1, determining the geometric features of the cage base and the geometric features of the opening limit structure;

[0069] The inner and outer contours of the retainer base are concentric circles; the opening limiting structures are arranged in an array around the axis inside the retainer base; and the axial thickness of the retainer base and the opening limiting structures are the same.

[0070] The geometric characteristic points P1, P2, P3, P4, P5, P6, P7, P8, P9 representing the axisymmetric basic shape of the opening limit structure; determine that the geometric contour shape of the opening limit structure is a curve segment, wherein the curve segment Represents the contour shape of the unloading chute structure, the curve segment With curve segment Represents the outline shape of the through-hole structure, a broken line segment With straight line segment Represents the contour shape of the raised structure, straight line segment Represents the contour shape of the end part; the curve segment P1P2 is on the inner circle of the cage base, and the straight line segment With curve segment Tangent.

[0071] The characteristic points P2, P3, P4, P5, P6, P7 and P9 have rounded corners.

[0072] Step 2: Determine the characteristic parameter dimensions H, R of the cage base and the opening limit structure a ,R b ,R c ,R d ,R1,R2,h1,h2,h3,h4,L1,L2; the axial thickness of the retaining frame base and the opening limiting structure is H.

[0073] Determine the curve segment where the origin O of the coordinate system of the basic outline shape of the opening limiting structure is located on the symmetry axis of the opening limiting structure The center of the circle;

[0074] Determine the common center coordinate C1 of the inner circle and the outer circle of the retaining frame base as X c , Y c ; where X c =0, Y c =-R c ; The inner circle diameter is R a , the outer diameter is R b , the number of arrays of the opening limiting structure around the axis is k;

[0075] Curve Segment The radius of the arc is R a , the coordinates of the center of the circle are C1; the coordinates of point P1 are X1, Y1; where X1=0, Y1=R a -R c ;

[0076] The coordinates of point P2 are X2, Y2; where X2 = h1,

[0077] Curve Segment The radius of the arc is R1, the coordinates of the center of the circle are O, and the coordinates of point P3 are X3, Y3; where X3 = h1,

[0078] The coordinates of point P4 are X4, Y4; where X4 = h2, h2 is the radius of the cylinders at the upper and lower ends of the roller;

[0079] The coordinates of point P5 are X5, Y5; where X5 = h3, Y5 = -h4;

[0080] Curve Segment The radius of the arc is R d , the coordinates of the center of the circle are C1, and the coordinates of point P6 are X6, Y6; where X6 = h2,

[0081] The coordinates of point P7 are X7, Y7;

[0082]

[0083] Curve Segment The arc radius is R2, the center coordinates are O, and the coordinates of point P8 are X8, Y8;

[0084] The coordinates of point P9 are X9, Y9;

[0085] The fillet radius at P2, P3, P6, P7, and P9 is L1, and the fillet radius at P4 and P5 is L2;

[0086] In this embodiment, H = 5 mm; R a =15.5mm; R b =17.5mm; R c =13mm; R d =10.5mm; R1=1.8mm; R2=2.75mm; h1=1mm; h2=1.75mm; h3=1.7mm; h4=2.4mm; L1=

[0087] 0.1mm; L2=0.2mm;

[0088] According to the calculation formula of each coordinate point, the coordinates of each point are determined as:

[0089] The coordinates of point C1 are X c =0,Y c =-13mm;

[0090] The coordinates of point P1 are X1=0, Y1=2.5mm;

[0091] The coordinates of point P2 are X2=1mm, Y2=2.47mm;

[0092] The coordinates of point P3 are X3=1mm, Y3=1.50mm;

[0093] The coordinates of point P4 are X4=1.75mm, Y4=0.42mm;

[0094] The coordinates of point P5 are X5=1.7mm, Y5=-2.4mm;

[0095] The coordinates of point P6 are X6=1.75mm, Y6=-2.65mm;

[0096] The coordinates of point P7 are X7=2.47mm, Y7=-2.79mm;

[0097] The coordinates of point P8 are X8=2.74mm, Y8=-0.29mm;

[0098] The coordinates of point P9 are X9=1.25mm, Y9=2.45mm;

[0099] Step 3, performing finite element assembly analysis; the finite element assembly analysis is based on the target requirement that the roller is radially inserted into the opening limit retainer, and uses ABAQUS finite element analysis software to perform finite element simulation analysis on the assembly process of the upper and lower cylinders of the roller radially inserted into the opening limit structure;

[0100] Step 4, determine whether the maximum Mises stress in the finite element assembly analysis result exceeds the yield limit of the material, and determine whether the maximum node reaction force in the finite element assembly analysis process exceeds 30N. If the maximum Mises stress in the finite element assembly analysis result does not exceed the yield limit of the material, and the maximum node reaction force in the finite element assembly analysis process does not exceed 30N, the opening limit retainer structure design is formed; if the stress result obtained by the finite element assembly analysis does not meet the requirements, repeat steps 2-3 until the stress result obtained by the finite element assembly analysis meets the requirements;

[0101] The maximum Mises stress in the finite element assembly analysis results of this embodiment is 726.7Mpa, which is lower than the yield limit of the steel material selected in this embodiment; the maximum node reaction force in the finite element assembly analysis of this embodiment is 11N, which is lower than 30N; therefore, the structural design of the opening limit retainer is formed. So far, the structural design of the opening limit retainer is completed.

Claims

1. A roller quick assembly tool, comprising an opening limit retainer, an auxiliary base and a roller, characterized in that: The roller quick assembly tooling is characterized in that the opening limit retainer is placed on an auxiliary base, and the auxiliary base is horizontally placed at the bottom of the opening limit retainer in the assembly body. There are two opening limit retainers, and the roller is vertically assembled in the opening limit retainer. The outer periphery of the opening limit retainer is a nut, and an inner gear ring is provided at the upper end of the roller between the roller and the inner diameter of the nut.

2. The roller quick assembly tool according to claim 1, characterized in that: In the roller quick assembly tooling, the opening limit retainer includes a retainer base and an opening limit structure. The retainer base is an annular structure. The inner diameter of the retainer base is provided with a plurality of evenly distributed opening limit structures. The opening limit structure is a symmetrical structure. Each opening limit structure includes a symmetrical unloading groove structure, a through hole structure, a protrusion structure and an end portion. Two groups of unloading groove structures, through hole structures, protrusion structures and the end portion form a buckle. The cylinders at the upper and lower ends of the roller are inserted into the through hole structure from the protrusion structure through the end portion.

3. The roller quick assembly tool according to claim 1, characterized in that: In the roller quick assembly tooling, the auxiliary base includes an auxiliary base base step, a retaining frame support step and a radial positioning ring. The auxiliary base base step is a cylindrical base at the bottom of the auxiliary base; the retaining frame support step is a disc-shaped support step arranged on the upper layer of the auxiliary base base step; and the radial positioning ring is a circular ring arranged on the upper layer of the retaining frame support step.

4. The roller quick assembly tool according to claim 3, characterized in that: In the roller quick assembly tool, a circular through hole is arranged at the center of the auxiliary base, the circular through hole is larger than the major diameter of the lead screw, and the auxiliary base base step, the retaining frame support step, and the radial positioning ring are coaxial with the circular through hole.

5. The roller quick assembly tool according to claim 3, characterized in that: In the roller quick assembly tool, the diameter of the auxiliary base step is larger than the diameter of the outer large end of the nut.

6. The roller quick assembly tool according to claim 3, characterized in that: In the roller quick assembly tool, the diameter of the cage support step is equal to the outer diameter of the opening limit cage.

7. The roller quick assembly tool according to claim 3, characterized in that: In the roller quick assembly tool, the diameter of the radial positioning ring is smaller than the inner diameter of the open limit retaining frame.

8. An assembly method using any one of the roller quick assembly tools according to claims 1 to 7, characterized in that The steps include: Step 1, take the auxiliary base, place the auxiliary base horizontally, place an opening limit retainer horizontally on the auxiliary base, then push the smooth inner groove of the inner gear ring horizontally downward to insert the opening limit retainer into the smooth inner groove of the inner gear ring, and then push the large end of the nut horizontally downward to insert the inner gear ring into the smooth inner groove of the nut; Step 2, take the inner gear ring, turn the smooth inner groove of the inner gear ring upward horizontally and insert the inner gear ring into the smooth inner groove of the small end of the nut, and then insert an open limit retainer into the smooth inner groove of the inner gear ring; Step 3, take a roller, place the roller vertically along the axis and insert the cylinders at the upper and lower ends of the roller into the opening limit structure in the opening limit retainer respectively, repeat the installation of the roller until all the rollers are installed at the corresponding positions of the rollers, then remove the auxiliary base and assemble the screw.

9. A method for designing an opening limit retainer using any roller quick assembly tool as claimed in any one of claims 1 to 7, characterized in that The steps include: Step 1, determining the geometric features of the retainer base and the geometric features of the opening limit structure; The inner and outer contours of the retainer base are concentric circles; the opening limit structure is arranged around the axis inside the retainer base; The axial thickness of the cage base and the opening limiting structure is the same; The geometric characteristic points of the axisymmetric shape of the opening limit structure are P1, P2, P3, P4, P5, P6, P7, P8, and P9 respectively; the geometric contour shape of the opening limit structure is a curve segment, wherein the curve segment Represents the contour shape of the unloading chute structure, the curve segment With curve segment Represents the outline shape of the through-hole structure, a broken line segment With straight line segment Represents the contour shape of the raised structure, straight line segment Represents the contour shape of the end part; curve segment On the inner circle of the cage base, the straight line segment With curve segment Tangent; The characteristic points P2, P3, P4, P5, P6, P7, and P9 have rounded corners; Step 2: Determine the characteristic parameter dimensions H, R of the cage base and the opening limit structure a ,R b ,R c ,R d , R1, R2, h1, h2, h3, h4, L1, L2; the axial thickness of the retaining frame base and the opening limiting structure is H; The coordinate system origin O of the basic outline shape of the opening limiting structure is located on the curve segment on the symmetry axis of the opening limiting structure. The center of the circle; The common center coordinate C1 of the inner circle and the outer circle of the retaining frame base is X c , Y c ; where X c =0, Y c =-R c ; The inner circle diameter is R a , the outer diameter is R b , the number of arrays of the opening limiting structure around the axis is k; Curve Segment The radius of the arc is R a , the coordinates of the center of the circle are C1; the coordinates of point P1 are X1, Y1; where X1=0, Y1=R a -R c ; The coordinates of point P2 are X2, Y2; where X2 = h1, Curve Segment The radius of the arc is R1, the coordinates of the center of the circle are O, and the coordinates of point P3 are X3, Y3; where X3 = h1, The coordinates of point P4 are X4, Y4; where X4 = h2, h2 is the radius of the cylinders at the upper and lower ends of the roller; The coordinates of point P5 are X5, Y5; where X5 = h3, Y5 = -h4; Curve Segment The radius of the arc is R d , the coordinates of the center of the circle are C1, and the coordinates of point P6 are X6, Y6; where X6 = h2, The coordinates of point P7 are X7, Y7; Curve Segment The arc radius is R2, the center coordinates are O, and the coordinates of point P8 are X8, Y8; where X8 = The coordinates of point P9 are X9, Y9; The fillet radius at P2, P3, P6, P7, and P9 is L1, and the fillet radius at P4 and P5 is L2; Step 3, perform finite element assembly analysis; Finite element assembly analysis is based on the target requirement of the roller being inserted into the open limit cage in the radial direction. The finite element analysis software ABAQUS is used to perform finite element simulation analysis on the assembly process of the roller upper and lower cylinders being inserted into the open limit structure in the radial direction. Step 4, judging whether the stress results obtained by the finite element assembly analysis meet the design requirements. The design requirements are that the maximum Mises stress in the finite element assembly analysis results does not exceed the yield limit of the material, and the maximum node reaction force in the finite element assembly analysis process does not exceed 30N. When the stress results obtained by the finite element assembly analysis meet the design requirements, the opening limit cage structure design is formed; If the stress results obtained by the finite element assembly analysis do not meet the requirements, repeat steps 2-3 until the stress results obtained by the finite element assembly analysis meet the design requirements; At this point, the structural design of the opening limit retainer is completed.

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