Circulating roller screw structure and design method thereof

Abstract

The invention provides a circulating roller screw structure and a design method thereof, a plurality of rollers are mounted in a neutral position of a support strip structure of a squirrel cage holder, the rollers are meshed with screw threads, two roller circulating control parts are respectively fixed on two sides of a screw thread section, and the two roller circulating control parts are respectively connected with the squirrel cage holder. The lead screw, the pin roller, the squirrel cage holder and the pin roller circulation control part serve as a whole and are jointly screwed into the nut, and the pin roller is meshed with an internal thread of the nut. According to the method for designing the contour of the circulating roller screw part by adopting the circular curve, the problem of part collision caused by thread dislocation when the roller and the screw are disengaged and re-engaged is solved, and the problem of discontinuous movement in the resetting movement of the roller is greatly improved.

Description

Technical Field

[0001] The invention relates to the field of structural design, in particular to a method for designing the contours of roller circulation control parts and nuts in a circulating roller screw by adopting circular arc curves. Background Art

[0002] Planetary roller screw is a precision mechanical transmission device that converts rotational motion into linear motion through thread meshing. The screw and nut of the circulating roller screw transmission are multi-start threads with the same tooth type. Compared with the standard planetary roller screw, although the circulating roller screw does not need to include a gear pair structure, the roller has axial movement and reset movement relative to the nut, and the helix angle of the roller and nut threads is also different. Therefore, the circulating roller screw has different meshing characteristics from the standard planetary roller screw, and the circulation and reset of the roller must be considered during the structural design.

[0003] Traditional circulating roller screws have problems such as interference between the roller thread and the screw and nut thread when the roller enters and exits the meshing, resulting in discontinuous motion during the reset process. The present invention includes a roller circulation control part with a reset structure and a corresponding nut, and proposes a design method for first disengaging the roller and then performing the reset motion. Compared with the traditional structure, the present invention can greatly improve the problem of discontinuous motion during the roller reset motion. Summary of the invention

[0004] In order to overcome the deficiencies of the prior art, the present invention provides a circulating roller screw structure and a design method thereof.

[0005] The technical solution adopted by the present invention to solve its technical problem is:

[0006] A circulating roller screw structure, comprising a screw 1, a nut 2, a roller 3, a cage holder 4 and a roller circulation control part 5; a plurality of rollers 3 are installed in the gap of the support bar structure of the cage holder 4, and the rollers 3 are meshed with the threads of the screw 1, and two roller circulation control parts 5 are respectively fixed on both sides of the threaded section of the screw 1, and the screw 1, the roller 3, the cage holder 4 and the roller circulation control part 5 are screwed into the nut 2 as a whole, and the rollers 3 are meshed with the internal threads of the nut 2;

[0007] Due to assembly requirements, the internal thread of the nut, the external thread of the screw and the roller annular tooth structure have the same pitch.

[0008] When the roller exits and re-enters the meshing, the roller annular tooth structure 3-1 does not interfere with the nut internal thread structure 2-1 and the lead screw external thread structure 1-2; and the roller optical axis structure 3-2 does not interfere with the roller cyclic control part circumferential motion upper control surface structure 5-2, circumferential motion lower control surface structure 5-3 and nut special-shaped groove structure 2-2 and nut internal thread structure 2-1 during the cycle.

[0009] The design steps of a circulating roller screw structure are:

[0010] Step 1: The horizontal distance corresponding to the meshing part between the roller and the lead screw and the nut in one cycle is x, and the horizontal distance corresponding to the reset movement of the roller is y. λ represents the helix angle of the helix part, and h represents the helix lift of the helix part. is the diameter of the screw, d2 is the contact circle diameter between the bottom of the roller and the roller circulation control part, h1 is the actual gap that should be left during assembly, h2 is the height of the section where the roller cannot contact, α is the central angle corresponding to the reset motion section of the roller, and P is the thread lead of the screw or nut;

[0011] in

[0012] (1)

[0013] (2)

[0014] (3)

[0015] (4)

[0016] (5)

[0017] The bottom of the roller is When the actual movement starts to reset, the actual contact point between roller 3 and roller circulation control part 5 is at an angle of The phase of the contact point is advanced, and the actual contact point has an angle of 1.3° compared to the theoretical contact point when the reset is completed. The phase is delayed. To ensure that the translation process does not affect the thread engagement, the central angle α is expanded to α1, and α1 satisfies:

[0018] (6)

[0019] Step 2: Design the roller cycle to control the part profile;

[0020] Step 3: Design the inner profile of the nut.

[0021] The specific steps of step 2 for designing the roller cycle control part profile are:

[0022] Determine the contour shape of the roller cycle control part; the contour shape of the roller cycle control part is composed of six continuous tangent arc curves P S1 ~P S6 The arc curve is designed to be composed of four parts: roller meshing with the screw, roller gradually disengaging from the screw, roller reset and roller meshing with the screw again. The meshing part between the roller and the screw is a section with a central angle of The arc P S1 The roller gradually disengages from the meshing part of the screw, which is two tangent arcs P. S2 and P S3 , the arc P tangent to the meshing part between the roller and the screw S2 The arc P with the corresponding central angle γ and tangent to the roller reset part S3 The corresponding central angle is The roller reset part is an arc P with a central angle of α. S4 , the roller re-engages with the screw for part of the arc P S5 and P S6 Same as the roller gradually disengaging from the screw engagement part;

[0023] Determine the profile shape of the roller circulation control part screw side. The origin O of the coordinate system is located at the center of the screw axial section circle. The curve segment P S1 The starting point is on the X axis, where the curve segment P S1 Represents the roller return segment roller cycle control part screw side profile shape, curve segment P S1 The corresponding radius is r1, and the corresponding central angle is , P S1 The polar coordinate equation of is shown in formula (11);

[0024] Curve segment P S2 ~P S3 Represents the side profile of the roller screw of the roller cycle control part in the meshing section between the roller and the screw and the nut. The corresponding center angle is , curve segment P S2 The corresponding radius is r2, the corresponding center angle is γ, and the corresponding center angle of the circle with r2 as radius is , P S2 The polar coordinate equation of the curve segment P is shown in formula (12); S3 The corresponding radius is r3, and the corresponding center angle of the circle with r3 as radius is , P S3 The polar coordinate equation of is shown in formula (13); where , , , γ satisfies the following equation:

[0025] (7)

[0026] (8)

[0027] (9)

[0028] (10)

[0029] Curve segment P S4 Represents the roller, lead screw and nut meshing segment at the same time. The roller cycle controls the side profile of the lead screw. The curve segment P S4 The corresponding radius is r4, P S4 The polar coordinate equation of is shown in formula (14);

[0030] Curve segment P S5 ~P S6 Represents the roller, screw and nut re-engagement section roller cycle control parts screw side profile shape, P S5 With curve segment P S3 The contour shape is the same, and the polar coordinate equation is shown in formula (15), P S6 With curve segment P S2 The contour shape is the same, and its polar coordinate equation is shown in formula (16);

[0031] Curve segment P S1 With curve segment P S2 Tangent, curve segment P S2 With curve segment P S3 Tangent, curve segment P S3 With curve segment P S4 Tangent, curve segment P S4 With curve segment P S5 Tangent, curve segment P S5 With curve segment P S6 Tangent, curve segment P S6 With curve segment P S1 Tangent;

[0032] The polar coordinate equation of the roller circulation structure screw side curve is:

[0033] (11)

[0034] (12)

[0035]

[0036] (13)

[0037] (14)

[0038]

[0039] (15)

[0040]

[0041] (16)

[0042] Among them, x 21 With y 21 P S6 The x and y coordinates of the arc segment corresponding to the center of the circle, x 21 With y 21 satisfy:

[0043] (17)

[0044] (18)

[0045] (19)

[0046] x 22 With y 22 P S2 The x and y coordinates of the arc segment corresponding to the center of the circle, x 21 With y 21 satisfy:

[0047] (20)

[0048] (twenty one)

[0049] (twenty two)

[0050] x 31 With y 31 P S5 The x and y coordinates of the arc segment corresponding to the center of the circle, x 31 With y 31 satisfy:

[0051] (twenty three)

[0052] (twenty four)

[0053] (25)

[0054] x 32 With y 32 P S3 The x and y coordinates of the arc segment corresponding to the center of the circle, x 32 With y 32 satisfy:

[0055] (26)

[0056] (27)

[0057] (28)

[0058] Determine the side profile shape of the roller circulation control part nut, the side profile shape of the roller circulation control part lead screw is composed of four arc curves P n1 ~P n4 Composition, n represents the roller circulation control part nut side, where the curve segment P n1 Represents the roller return segment roller cycle control part nut side profile shape, curve segment P n2 Represents the re-engagement segment between the roller and the screw and the nut. The roller cycle control part nut side curve, curve segment P n3 Represents the roller, lead screw and nut meshing segment at the same time. The roller cycle controls the nut side profile of the part. The curve segment P n4 Represents the roller, lead screw and nut disengagement segment roller cycle control part nut side profile shape; curve segment P n2 With curve segment P n3 Tangent, curve segment P n3 With curve segment P n4 Tangent;

[0059] Make sure that the nut side profile coordinate system of the roller cycle control part coincides with the screw side profile shape coordinate system of the column cycle control part. n1 The starting point is located on the X axis;

[0060] Curve segment P n1 The radius of the arc is r n1 , and its corresponding central angle is α n , its polar coordinate equation is shown in formula (29);

[0061] Curve segment P n2 The radius of the arc is r n2 , and its corresponding central angle is , its polar coordinate equation is shown in formula (30);

[0062] Curve segment P n3 The radius of the arc is r n3 , its polar coordinate equation is shown in formula (31);

[0063] Curve segment P n4 The radius of the arc is r n2 , and its corresponding central angle is , its polar coordinate equation is shown in formula (32);

[0064] The polar coordinate equation of the nut side curve of the roller circulation structure is:

[0065] (29)

[0066]

[0067] (30)

[0068] (31)

[0069]

[0070] (32)

[0071] Among them, x n21 With y n21 P n4 The x and y coordinates of the arc segment corresponding to the center of the circle, x n21 With y n21 satisfy:

[0072] (33)

[0073] (34)

[0074] (35)

[0075] Among them, x n22 With y n22 P n2 The x and y coordinates of the arc segment corresponding to the center of the circle, x n22 With y n22 satisfy:

[0076] (36)

[0077] (37)

[0078] (38)

[0079] At this point, the structural design of the roller circulation control parts is completed;

[0080] The specific steps of step 3 for designing the inner profile of the nut are:

[0081] Determine the contour shape of the inner side of the nut, the contour shape of the inner side of the nut includes four arc curves P N1 ~P N4 ;

[0082] Make sure that the inner contour coordinate system of the nut coincides with the contour shape coordinate system of the screw side of the column cycle control part. N1 The starting point is located on the X axis;

[0083] Among them, the curve segment P N1 Represents the inner curve of the roller nut in the roller return section, with an arc radius of r N1 , and its corresponding central angle is α N , its polar coordinate equation is shown in formula (39):

[0084] (39)

[0085] Curve segment P N2 ~P N4 It is composed of three continuous tangent arcs, and the curve segment P N2 Represents the inner curve of the nut during the re-engagement of the roller, the screw and the nut, P N2 With P N1 Tangent, arc radius is r N2 , and its corresponding central angle is , its polar coordinate equation is shown in formula (40):

[0086]

[0087] (40)

[0088] Curve segment P N3 Represents the inner curve of the nut in the section where the roller, the lead screw and the nut are meshed at the same time, and the arc radius is r N3 , its polar coordinate equation is shown in formula (41):

[0089] (41)

[0090] Curve segment P N4 Represents the roller, the screw and the nut disengagement section. The inner curve of the nut, curve segment P N4 Contour shape and curve segment P N2 Same, P N4 With P N1 Tangent, arc radius is r N2 , and its corresponding central angle is , its polar coordinate equation is shown in formula (42):

[0091]

[0092] (42)

[0093] The polar coordinate equation of the curve inside the nut is:

[0094] Among them, xN21 With y N21 P N4 The x and y coordinates of the arc segment corresponding to the center of the circle, x N21 With y N21 satisfy:

[0095] (43)

[0096] (44)

[0097] (45)

[0098] Among them, x N22 With y N22 P N2 The x and y coordinates of the arc segment corresponding to the center of the circle, x N22 With y N22 satisfy:

[0099] (46)

[0100] (47)

[0101] (48)

[0102] The design of the inner curve of the nut is now completed.

[0103] The beneficial effect of the present invention is that the present invention proposes a method of designing the contour of a circulating roller screw part using an arc curve, thereby solving the problem of part collision caused by thread misalignment when the roller and the screw are disengaged and re-engaged, and greatly improving the problem of discontinuous motion in the roller resetting motion of the electromechanical actuator and the motor during movement. BRIEF DESCRIPTION OF THE DRAWINGS

[0104] Figure 1 It is a schematic diagram of a circulating roller screw mechanism.

[0105] Figure 2 It is a schematic diagram of the cross-sectional position of a circulating roller screw mechanism.

[0106] Figure 3 It is a schematic diagram of the AA section of a circulating roller screw mechanism.

[0107] Figure 4 It is a schematic diagram of the cross section of the circulating roller screw mechanism BB.

[0108] Figure 5 It is a flow chart for designing roller circulation control parts and nuts.

[0109] Figure 6 It is a schematic diagram of the axial displacement of the roller relative to the screw during the cycle.

[0110] Figure 7 It is a schematic diagram of the axial clearance of the nut structure.

[0111] Figure 8 It is a schematic diagram of the screw structure.

[0112] Fig. 9 This is a diagram of a nut.

[0113] Fig.10 This is the structure diagram of the annular roller.

[0114] Fig.11 It is a schematic diagram of the squirrel cage retainer structure.

[0115] Fig.12 This is a schematic diagram of the roller circulation control parts structure Figure 1 .

[0116] Fig.13 This is a schematic diagram of the roller circulation control parts structure Figure 2 .

[0117] Fig.14 It is a curve diagram of the screw side of the roller circulation structure.

[0118] Fig.15 It is a schematic diagram of the nut side curve of the roller circulation structure.

[0119] Fig.16 It is a schematic diagram of the inner curve of the nut.

[0120] Among them, 1 is a screw, 2 is a nut, 3 is a roller, 4 is a squirrel cage, 5 is a roller circulation control part, 1-1 is a push rod, 1-2 is an external thread, 2-1 is an internal thread of a nut, 2-2 is a special-shaped groove structure, 2-2a is a first arc segment, 2-2b is a second arc segment, 2-2c is a third arc segment, 2-3 is a roller circulation control part fixed surface structure, 2-4 is a roller circulation control part mounting surface structure, 3-1 is an annular tooth structure, 3-2 is an optical axis structure, 4-1 is an open groove structure in an annular layout, and 4-2 is an annular layout. The outer opening groove structure, 4-3 is the annular support strip structure, 5-1 is the axial motion control surface structure, 5-2 is the circumferential motion upper control surface structure, 5-3 is the circumferential motion lower control surface structure, 5-4 is the inner circular surface structure, 5-1a is the spiral surface structure, 5-1b is the spline surface structure, 5-2a is the circular motion upper control arc surface structure, 5-2b is the reset motion upper control arc surface structure, 5-3a is the circular motion lower control arc surface structure, 5-3b is the reset motion lower control arc surface structure, 5-5 is the roller circulation control part process groove, R d It is the revolution direction of roller 3. DETAILED DESCRIPTION

[0121] The present invention is further described below in conjunction with the accompanying drawings and embodiments.

[0122] This example is a design of a circulating roller screw. The roller circulating control part is composed of two parts: an engagement section and a reset section. The curve equation corresponding to the contour is established according to the radius and center of each section of the roller circulating control part.

[0123] Among them, 1 is a lead screw, 2 is a nut, 3 is an annular roller, 4 is a squirrel cage, and 5 is a roller circulation control part. The lead screw 1 includes two sections, one of which is a push rod 1-1, and the other section is provided with an external thread 1-2. The nut 2 is a single-start internal thread, which includes a total of four sections, one of which is an internal thread 2-1. The nut internal thread 2-1 is cut off by a special-shaped groove structure 2-2. The axial section of the special-shaped groove structure 2-2 is three sections of continuous tangent arcs, namely the first arc segment 2-2a, the second arc segment 2-2b and the third arc segment 2-2c. The two ends of the internal thread 2-1 are provided with a roller circulation control part fixing surface structure 2-3 and a roller circulation control part mounting surface structure 2-4. The roller 3 is also divided into three sections, the middle section is an annular tooth structure 3-1, and both ends of the annular tooth structure 3-1 are optical axis structures 3-2. The designed squirrel cage holder 4 is a three-section structure, the front section is an annular layout inner open groove structure 4-1, the rear section is an annular layout outer open groove structure 4-2, and the middle section is an annular layout support bar structure 4-3. The designed squirrel cage holder 4 is a three-section structure, the front section is an annular layout inner open groove structure 4-1, the rear section is an annular layout outer open groove structure 4-2, and the middle section is an annular layout support bar structure 4-3. The roller circulation control part 5 is a circular ring structure, and a special-shaped groove is opened on the side wall of the ring. The special-shaped groove includes an axial motion control surface structure 5-1, a circumferential motion upper control surface structure 5-2, a circumferential motion lower control surface structure 5-3 and an inner circular surface structure 5-4. The axial motion control surface structure 5-1 is the outer side wall of the special-shaped groove, the circumferential motion upper control surface structure 5-2 is the bottom surface of the special-shaped groove, the circumferential motion lower control surface structure 5-3 is the inner side wall of the special-shaped groove, and the inner circular surface structure 5-4 is the side wall of the inner ring of the roller circulation control part 5. The axial motion control surface structure 5-1 is a spiral The curved surface structure 5-1a is connected to the spline curved surface structure 5-1b, the upper control surface structure 5-2 for circumferential motion is the upper control arc surface structure 5-2a for circular motion connected to the upper control arc surface structure 5-2b for reset motion, the lower control surface structure 5-3 for circumferential motion is the lower control arc surface structure 5-3a for circular motion connected to the lower control arc surface structure 5-3b for reset motion, the spline curved surface structure 5-1b, the upper control arc surface structure 5-2b for reset motion and the lower control arc surface structure 5-3b for reset motion together constitute the roller reset motion control structure in the roller circulation control part 5.

[0124] The circulating roller screw parts of this embodiment include roller circulation control parts and nuts. The specific design process includes the following steps:

[0125] Step 1: Design the geometric non-interference conditions of the circulating roller screw, and the specific process is as follows: for the circulating roller screw transmission mechanism, due to assembly requirements, the nut internal thread, the screw external thread and the roller annular tooth structure have the same pitch; when the roller exits and re-enters the meshing, the roller annular tooth structure 3-1 does not interfere with the nut internal thread structure 2-1 and the screw external thread structure 1-2; and the roller optical axis structure 3-2 does not interfere with the roller circulation control part circumferential motion upper control surface structure 5-2, circumferential motion lower control surface structure 5-3 and the nut special-shaped groove structure 2-2, and the nut internal thread structure 2-1 during the cycle.

[0126] The horizontal distance corresponding to the meshing part between the roller and the lead screw and the nut in one cycle is x, and the horizontal distance corresponding to the roller's reset movement is y. λ represents the helical angle of the helical part, and h represents the helical lift of the helical part. is the diameter of the screw, d2 is the contact circle diameter between the bottom of the roller and the roller circulation control part, h1 is the actual gap that should be left during assembly, and h2 is the height of the section where the roller cannot contact. α is the center angle corresponding to the reset motion section of the roller, and P is the thread lead of the screw or nut.

[0127] in

[0128] (1)

[0129] (2)

[0130] (3)

[0131] (4)

[0132] (5)

[0133] In this embodiment , 10mm, , According to the calculation formula of each parameter, the value of each parameter is determined as follows:

[0134] (49)

[0135] (50)

[0136] (51)

[0137] (52)

[0138] (53)

[0139] The bottom of the roller is When the actual movement starts to reset, the actual contact point between roller 3 and roller circulation control part 5 is at an angle of The phase of the contact point is advanced, and the actual contact point has an angle of 1.3° compared to the theoretical contact point when the reset is completed. The phase is delayed. To ensure that the translation process does not affect the thread engagement, the central angle α should be expanded to α1, and α1 satisfies:

[0140] (6)

[0141] Step 2: Design the contour of the roller circulation control part. The specific process is as follows: determine the contour shape of the roller circulation control part; the contour shape of the roller circulation control part is composed of six continuous tangent arc curves, and the arc curve is designed to be four parts: the roller is engaged with the screw, the roller gradually disengages from the screw, the roller is reset, and the roller is re-engaged with the screw. The meshing part of the roller and the screw is a section with a central angle of The arc P S1 The roller gradually disengages from the meshing part of the screw, which is two tangent arcs P. S2 and P S3 , the arc P tangent to the meshing part between the roller and the screw S2 The arc P with the corresponding central angle γ and tangent to the roller reset part S3 The corresponding central angle is The roller reset part is an arc P with a central angle of α. S4 , the roller re-engages with the screw for part of the arc P S5 and P S6 Same as the roller gradually disengaging from the screw engagement part;

[0142] The origin O of the coordinate system that determines the contour shape of the roller cycle control part is located at the center of the axial section of the screw. S1 The starting point is located on the X axis.

[0143] Among them, the curve segment P S1 Represents the roller return segment roller cycle control part screw side profile shape, curve segment P S1 The corresponding radius is r1, and the corresponding central angle is , P S1 The polar coordinate equation of is shown in formula (11);

[0144] Curve segment P S2 ~P S3 Represents the side profile of the roller screw of the roller cycle control part in the meshing section between the roller and the screw and the nut. The corresponding center angle is , curve segment PS2 The corresponding radius is r2, the corresponding center angle is γ, and the corresponding center angle of the circle with r2 as radius is , P S2 The polar coordinate equation of is shown in formula (12);

[0145] Curve segment P S3 The corresponding radius is r3, and the corresponding center angle of the circle with r3 as radius is , P S3 The polar coordinate equation of is shown in formula (13);

[0146] Curve segment P S4 Represents the roller, lead screw and nut meshing segment at the same time. The roller cycle controls the side profile of the lead screw. The curve segment P S4 The corresponding radius is r4, P S4 The polar coordinate equation of is shown in formula (14);

[0147] Curve segment P S5 ~P S6 Represents the roller, screw and nut re-engagement section roller cycle control parts screw side profile shape, P S5 With curve segment P S3 The contour shape is the same, and its polar coordinate equation is shown in formula (15), P S6 With curve segment P S2 The contour shape is the same, and its polar coordinate equation is shown in formula (16);

[0148] Curve segment P S1 With curve segment P S2 Tangent, curve segment P S2 With curve segment P S3 Tangent, curve segment P S3 With curve segment P S4 Tangent, curve segment P S4 With curve segment P S5 Tangent, curve segment P S5 With curve segment P S6 Tangent, curve segment P S6 With curve segment P S1 Tangent. Among them, φ1, φ2, φ3, and γ satisfy the following equation:

[0149] (7)

[0150] (8)

[0151] (9)

[0152] (10)

[0153] The polar coordinate equation of the roller circulation structure screw side curve is:

[0154] (11)

[0155] (12)

[0156]

[0157] (13)

[0158] (14)

[0159]

[0160] (15)

[0161]

[0162] (16)

[0163] Among them, x 21 With y 21 P S6 The x and y coordinates of the arc segment corresponding to the center of the circle, x 21 With y 21 satisfy:

[0164] (17)

[0165] (18)

[0166] (19)

[0167] x 22 With y 22 P S2 The x and y coordinates of the arc segment corresponding to the center of the circle, x 21 With y 21 satisfy:

[0168] (20)

[0169] (twenty one)

[0170] (twenty two)

[0171] x 31 With y 31 P S5 The x and y coordinates of the arc segment corresponding to the center of the circle, x 31 With y31 satisfy:

[0172] (twenty three)

[0173] (twenty four)

[0174] (25)

[0175] x 32 With y 32 P S3 The x and y coordinates of the arc segment corresponding to the center of the circle, x 32 With y 32 satisfy:

[0176] (26)

[0177] (27)

[0178] (28)

[0179] In this embodiment, , , , , According to the parameter calculation formula, the parameter values ​​are determined as , , , According to the calculation formula of the curve, the polar coordinate equation of the roller circulation structure screw side curve is determined as:

[0180] (54)

[0181]

[0182] (55)

[0183]

[0184] (56)

[0185] (57)

[0186]

[0187] (58)

[0188]

[0189] (59)

[0190] Determine the side profile shape of the roller circulation control part nut, the side profile shape of the roller circulation control part lead screw is composed of four arc curves P n1 ~P n4 The curve segment P n1 Represents the roller return segment roller cycle control part nut side profile shape, curve segment P n2 Represents the re-engagement segment between the roller and the screw and the nut. The roller cycle control part nut side curve, curve segment P n3 Represents the roller, lead screw and nut meshing segment at the same time. The roller cycle controls the nut side profile of the part. The curve segment P n4 Represents the roller, lead screw and nut disengagement segment roller cycle control part nut side profile shape; curve segment P n2 With curve segment P n3 Tangent, curve segment P n3 With curve segment P n4 Tangent;

[0191] Make sure that the nut side profile coordinate system of the roller circulation control part coincides with the screw side profile shape coordinate system of the column circulation control part. n1 The starting point is located on the X axis;

[0192] Curve segment P n1 The radius of the arc is r n1 , and its corresponding central angle is α n , its polar coordinate equation is shown in formula (29);

[0193] Curve segment P n2 The radius of the arc is r n2 , and its corresponding central angle is , its polar coordinate equation is shown in formula (30);

[0194] Curve segment P n3 The radius of the arc is r n3 , its polar coordinate equation is shown in formula (31);

[0195] Curve segment P n4 The radius of the arc is r n2 , and its corresponding central angle is , its polar coordinate equation is shown in formula (32);

[0196] The polar coordinate equation of the nut side curve of the roller circulation structure is:

[0197] (29)

[0198]

[0199] (30)

[0200] (31)

[0201]

[0202] (32)

[0203] Among them, x n21 With y n21 P n4 The x and y coordinates of the arc segment corresponding to the center of the circle, x n21 With y n21 satisfy:

[0204] (33)

[0205] (34)

[0206] (35)

[0207] Among them, x n22 With y n22 P n2 The x and y coordinates of the arc segment corresponding to the center of the circle, x n22 With y n22 satisfy:

[0208] (36)

[0209] (37)

[0210] (38)

[0211] In this embodiment, , , , , According to the calculation formula of the curve, the polar coordinate equation of the roller circulation structure nut side curve is determined as:

[0212] (60)

[0213]

[0214] (61)

[0215] (62)

[0216]

[0217] (63)

[0218] At this point, the structural design of the roller circulation control parts is completed.

[0219] Step 3: Design the inner profile of the nut. The specific process is as follows:

[0220] Determine the contour shape of the inner side of the nut, the inner side contour shape of the nut is composed of four arc curves P N1 ~P N4 composition;

[0221] Make sure that the inner contour coordinate system of the nut coincides with the contour shape coordinate system of the screw side of the column cycle control part. N1 The starting point is located on the X axis;

[0222] Among them, the curve segment P N1 Represents the inner curve of the roller nut in the roller return section, with an arc radius of r N1 , and its corresponding central angle is α N , its polar coordinate equation is shown in formula (39);

[0223] Curve segment P N2 ~P N4 It is composed of three continuous tangent arcs, and the curve segment P N2 Represents the inner curve of the nut during the re-engagement of the roller, the screw and the nut, P N2 With P N1 Tangent, arc radius is r N2 , and its corresponding central angle is , its polar coordinate equation is shown in formula (40);

[0224] Curve segment P N3 Represents the inner curve of the nut in the section where the roller, the lead screw and the nut are meshed at the same time, and the arc radius is r N3 , its polar coordinate equation is shown in formula (41);

[0225] Curve segment P N4 Represents the roller, the screw and the nut disengagement section. The inner curve of the nut, curve segment P N4 Contour shape and curve segment P N2 Same, P N4 With P N1 Tangent, arc radius is r N2 , and its corresponding central angle is , and its polar coordinate equation is shown in formula (42).

[0226] The polar coordinate equation of the curve inside the nut is:

[0227] (39)

[0228]

[0229] (40)

[0230] (41)

[0231]

[0232] (42)

[0233] Among them, x N21 With y N21 P N4 The x and y coordinates of the arc segment corresponding to the center of the circle, x N21 With y N21 satisfy:

[0234] (43)

[0235] (44)

[0236] (45)

[0237] Among them, x N22 With y N22 P N2 The x and y coordinates of the arc segment corresponding to the center of the circle, x N22 With y N22 satisfy:

[0238] (46)

[0239] (47)

[0240] (48)

[0241] In this embodiment, , , , , According to the calculation formula of the curve, the polar coordinate equation of the inner side curve of the nut is determined as follows:

[0242] (64)

[0243]

[0244] (65)

[0245] (66)

[0246]

[0247] (67)

[0248] The design of the inner curve of the nut is now completed.

Claims

1. A circulating roller screw structure, comprising a screw, a nut, a roller, a squirrel cage and a roller circulation control part, characterized in that: The circulating roller screw structure has multiple rollers installed in the gap of the support bar structure of the squirrel cage retainer, and the rollers are meshed with the screw threads. Two roller circulation control parts are respectively fixed on both sides of the screw thread section. The screw, rollers, squirrel cage retainer and roller circulation control parts are screwed into the nut as a whole, and the rollers are meshed with the internal threads of the nut.

2. The circulating roller screw structure according to claim 1, characterized in that: The internal thread of the nut, the external thread of the screw and the roller annular tooth structure have the same pitch.

3. The circulating roller screw structure according to claim 1, characterized in that: When the roller exits and re-enters the meshing, the roller annular tooth structure does not interfere with the nut internal thread structure and the screw external thread structure; and during the cycle, the roller optical axis structure does not interfere with the roller cycle control part circumferential motion upper control surface structure, circumferential motion lower control surface structure and nut special-shaped groove structure, and nut internal thread structure.

4. A design method for a circulating roller screw structure, using the circulating roller screw structure according to claim 1, characterized in that The steps include: Step 1: The horizontal distance corresponding to the meshing part between the roller and the lead screw and the nut in one cycle is x, and the horizontal distance corresponding to the reset movement of the roller is y. λ represents the helix angle of the helix part, and h represents the helix lift of the helix part. is the diameter of the screw, d2 is the contact circle diameter between the bottom of the roller and the roller circulation control part, h1 is the actual gap that should be left during assembly, h2 is the height of the section where the roller cannot contact, α is the central angle corresponding to the reset motion section of the roller, and P is the thread lead of the screw or nut; in (1); (2); (3); (4); (5); The bottom of the roller is When the actual movement starts to reset, the actual contact point between the roller and the roller circulation control part is at an angle of The phase of the contact point is advanced, and the actual contact point has an angle of 1.3° compared to the theoretical contact point when the reset is completed. The phase is delayed. To ensure that the translation process does not affect the thread engagement, the central angle α is expanded to α1, and α1 satisfies: (6); Step 2: Design the roller cycle to control the part profile; Step 3: Design the inner profile of the nut.

5. The design method of the circulating roller screw structure according to claim 4 is characterized in that: The specific steps of step 2 for designing the roller cycle control part profile are: Determine the contour shape of the roller cycle control part; the contour shape of the roller cycle control part is composed of six continuous tangent arc curves P S1 ~P S6 The arc curve is designed to be composed of four parts: roller meshing with the screw, roller gradually disengaging from the screw, roller reset and roller meshing with the screw again. The meshing part between the roller and the screw is a section with a central angle of The arc P S1 The roller gradually disengages from the meshing part of the screw, which is two tangent arcs P. S2 and P S3 , the arc P tangent to the meshing part between the roller and the screw S2 The arc P with the corresponding central angle γ and tangent to the roller reset part S3 The corresponding central angle is The roller reset part is an arc P with a central angle of α. S4 , the roller re-engages with the screw for part of the arc P S5 and P S6 Same as the roller gradually disengaging from the screw engagement part; Determine the profile shape of the roller circulation control part screw side. The origin O of the coordinate system is located at the center of the screw axial section circle, and the curve segment P S1 The starting point is on the X axis, where the curve segment P S1 Represents the roller return segment roller cycle control part screw side profile shape, curve segment P S1 The corresponding radius is r1, and the corresponding central angle is , P S1 The polar coordinate equation of is shown in formula (11); Curve segment P S2 ~P S3 Represents the side profile of the roller screw of the roller cycle control part in the meshing section between the roller and the screw and the nut. The corresponding center angle is , curve segment P S2 The corresponding radius is r2, the corresponding center angle is γ, and the corresponding center angle of the circle with r2 as radius is , P S2 The polar coordinate equation of the curve segment P is shown in formula (12); S3 The corresponding radius is r3, and the corresponding center angle of the circle with r3 as radius is , P S3 The polar coordinate equation of is shown in formula (13); where , , , γ satisfies the following equation: (7); (8); (9); (10); Curve segment P S4 Represents the roller, lead screw and nut meshing segment at the same time. The roller cycle controls the side profile of the lead screw. The curve segment P S4 The corresponding radius is r4, P S4 The polar coordinate equation of is shown in formula (14); Curve segment P S5 ~P S6 Represents the roller, screw and nut re-engagement section roller cycle control parts screw side profile shape, P S5 With curve segment P S3 The contour shape is the same, and the polar coordinate equation is shown in formula (15), P S6 With curve segment P S2 The contour shape is the same, and its polar coordinate equation is shown in formula (16); Curve segment P S1 With curve segment P S2 Tangent, curve segment P S2 With curve segment P S3 Tangent, curve segment P S3 With curve segment P S4 Tangent, curve segment P S4 With curve segment P S5 Tangent, curve segment P S5 With curve segment P S6 Tangent, curve segment P S6 With curve segment P S1 Tangent; The polar coordinate equation of the roller circulation structure screw side curve is: (11); (12); ; (13); (14); ; (15); ; (16); Among them, x 21 With y 21 P S6 The x and y coordinates of the arc segment corresponding to the center of the circle, x 21 With y 21 satisfy: (17); (18); (19) x 22 With y 22 P S2 The x and y coordinates of the arc segment corresponding to the center of the circle, x 21 With y 21 satisfy: (20); (21); (22); x 31 With y 31 P S5 The x and y coordinates of the arc segment corresponding to the center of the circle, x 31 With y 31 satisfy: (23); (24); (25); x 32 With y 32 P S3 The x and y coordinates of the arc segment corresponding to the center of the circle, x 32 With y 32 satisfy: (26); (27); (28); Determine the side profile shape of the roller circulation control part nut, the side profile shape of the roller circulation control part lead screw is composed of four arc curves P n1 ~P n4 Composition, n represents the roller circulation control part nut side, where the curve segment P n1 Represents the roller return segment roller cycle control part nut side profile shape, curve segment P n2 Represents the re-engagement segment between the roller and the screw and the nut. The roller cycle control part nut side curve, curve segment P n3 Represents the roller, lead screw and nut meshing segment at the same time. The roller cycle controls the nut side profile of the part. The curve segment P n4 Represents the roller, lead screw and nut disengagement segment roller cycle control part nut side profile shape; curve segment P n2 With curve segment P n3 Tangent, curve segment P n3 With curve segment P n4 Tangent; Make sure that the nut side profile coordinate system of the roller cycle control part coincides with the screw side profile shape coordinate system of the column cycle control part. n1 The starting point is located on the X axis; Curve segment P n1 The radius of the arc is r n1 , and its corresponding central angle is α n , its polar coordinate equation is shown in formula (29); Curve segment P n2 The radius of the arc is r n2 , and its corresponding central angle is , its polar coordinate equation is shown in formula (30); Curve segment P n3 The radius of the arc is r n3 , its polar coordinate equation is shown in formula (31); Curve segment P n4 The radius of the arc is r n2 , and its corresponding central angle is , its polar coordinate equation is shown in formula (32); The polar coordinate equation of the nut side curve of the roller circulation structure is: (29); ; (30); (31); ; (32); Among them, x n21 With y n21 P n4 The x and y coordinates of the arc segment corresponding to the center of the circle, x n21 With y n21 satisfy: (33); (34); (35); Among them, x n22 With y n22 P n2 The x and y coordinates of the arc segment corresponding to the center of the circle, x n22 With y n22 satisfy: (36); (37); (38); At this point, the structural design of the roller circulation control parts is completed.

6. The design method of the circulating roller screw structure according to claim 4 is characterized in that: The specific steps of step 3 for designing the inner profile of the nut are: Determine the contour shape of the inner side of the nut, the contour shape of the inner side of the nut includes four arc curves P N1 ~P N4 ; Make sure that the inner contour coordinate system of the nut coincides with the contour shape coordinate system of the screw side of the column cycle control part. N1 The starting point is located on the X axis; Among them, the curve segment P N1 Represents the inner curve of the roller nut in the roller return section, with an arc radius of r N1 , and its corresponding central angle is α N , its polar coordinate equation is shown in formula (39): (39); Curve segment P N2 ~P N4 It is composed of three continuous tangent arcs, and the curve segment P N2 Represents the inner curve of the nut during the re-engagement of the roller, the screw and the nut, P N2 With P N1 Tangent, arc radius is r N2 , and its corresponding central angle is , its polar coordinate equation is shown in formula (40): ; (40); Curve segment P N3 Represents the inner curve of the nut in the section where the roller, the lead screw and the nut are meshed at the same time, and the arc radius is r N3 , its polar coordinate equation is shown in formula (41): (41); Curve segment P N4 Represents the roller, the screw and the nut disengagement section. The inner curve of the nut, curve segment P N4 Contour shape and curve segment P N2 Same, P N4 With P N1 Tangent, arc radius is r N2 , and its corresponding central angle is , its polar coordinate equation is shown in formula (42): ; (42); The polar coordinate equation of the curve inside the nut is: Among them, x N21 With y N21 P N4 The x and y coordinates of the arc segment corresponding to the center of the circle, x N21 With y N21 satisfy: (43); (44); (45); Among them, x N22 With y N22 P N2 The x and y coordinates of the arc segment corresponding to the center of the circle, x N22 With y N22 satisfy: (46); (47); (48); The design of the inner curve of the nut is now completed.

Images