Circulator, ball screw, and electric cylinder
By setting a connection structure of circulator channels and limiting components on the lead screw, the problems of compactness and machining accuracy of ball screws in scenarios with small lead screw size are solved, thus achieving compactness and improved machining accuracy of ball screws.
Patent Information
- Application Number
- CN202520357269.9
- Authority / Receiving Office
- CN · China
- Patent Type
- Utility models(China)
- Current Assignee / Owner
- Filing Date
- 2025-03-03
- Publication Date
- 2026-01-09
- Estimated Expiration
- 2035-03-03
AI Technical Summary
In applications where the ball screw size is small, existing technologies struggle to achieve compactness and improved machining accuracy, making the manufacturing process quite challenging.
The circulator uses a grooved surface with an arched surface. By setting circulator channels on the lead screw to connect adjacent spiral channels, and combined with the connection structure of the limiting component, the processing technology is simplified and the processing difficulty is reduced.
It achieves compact ball screw design, reduces machining difficulty and improves machining accuracy, and is suitable for applications with small screw size.
Smart Images
Figure CN223782011U_ABST
Abstract
Description
Technical Field
[0001] This disclosure relates to the field of linear actuator technology, and particularly to a circulator, a ball screw including the circulator, and an electric cylinder. Background Technology
[0002] Ball screws are a key component of electric cylinders. Their principle involves the cyclic rolling of balls between a screw and a nut, converting rotational motion into linear motion. In applications where the screw size is small, precision machining of both the screw and nut is required, demanding extremely high accuracy in both machining and assembly. Therefore, achieving compact design of the circulator and ball screw, reducing machining difficulty, and improving machining accuracy have become pressing issues. Utility Model Content
[0003] This disclosure provides a circulator, a ball screw, and an electric cylinder.
[0004] In a first aspect, embodiments of this disclosure provide a circulator, the circulator including a grooved surface and a connecting surface, the grooved surface being an arched surface; multiple circulator channels extending in a circumferential direction are formed on the grooved surface; one circulator channel is used to connect two adjacent channels on a lead screw; the connecting surface is used to cooperate with the lead screw to install the circulator on the lead screw.
[0005] In some embodiments, the edge of the circulator channel bends inward to form an inner rim, which extends along the direction of the groove toward the interior of the circulator channel.
[0006] In some embodiments, the shape of the inner rim matches the trajectory of the ball as it enters the circulator channel.
[0007] In some embodiments, the two ports of the circulator channel each correspond to an inner rim; the inner rim faces the contour curve corresponding to the port and matches the movement trajectory of the ball entering the circulator channel.
[0008] In some embodiments, the length of the contour curve of the inner rim facing the corresponding port is not less than 1 / 2 of the circumference of the ball.
[0009] In some embodiments, the connecting surface is a plane, and a first connecting mechanism is provided on the connecting surface.
[0010] In some embodiments, the first connecting mechanism includes a limiting member protruding from the connecting surface.
[0011] In some embodiments, the material of the circulator includes any one of plastic, resin, and metal.
[0012] Secondly, this disclosure provides a ball screw, including a nut, a screw rod, and balls. The ball screw also includes a circulator as described above. The outer periphery of the screw rod includes a mounting surface and a threaded surface, and a groove is provided on the threaded surface. The connecting surface of the circulator is engaged with the mounting surface, and the groove surface of the circulator matches the outer periphery of the threaded surface. The circulator groove provided on the groove surface of the circulator connects two adjacent grooves on the threaded surface to form a circulating raceway. The balls are disposed in the circulating raceway.
[0013] In some embodiments, the connecting surface is a plane, and a first connecting mechanism is provided on the connecting surface; the mounting surface is a plane that matches the connecting surface, and a second connecting mechanism is provided on the mounting surface; the first connecting mechanism and the second connecting mechanism are connected in cooperation.
[0014] In some embodiments, the first connecting mechanism includes a limiting member protruding from the connecting surface; the second connecting mechanism includes a limiting groove disposed on the mounting surface; the limiting member is engaged with the limiting groove.
[0015] Thirdly, embodiments of this disclosure provide an electric cylinder, including a driver and a ball screw as described above, wherein the driver drives the ball screw to operate.
[0016] The circulator according to the embodiments of this disclosure has a simple structure, can reduce the size of components, and can be manufactured using simple molds such as coreless casting molds, thus achieving a compact circulation system. The circulator of the embodiments of this disclosure can be applied to applications where the ball screw size is small, enabling the circulator and ball screw to be compact, reducing the machining difficulty of the ball screw, and improving machining accuracy. Attached Figure Description
[0017] Figure 1 This is a perspective view of a ball screw according to an embodiment of the present disclosure;
[0018] Figure 2 This is a perspective view of a lead screw according to an embodiment of this disclosure;
[0019] Figure 3 This is a cross-sectional schematic diagram of a lead screw according to an embodiment of this disclosure;
[0020] Figure 4 This is a schematic diagram of the structure of a circulator according to an embodiment of the present disclosure;
[0021] Figure 5 This is a top view of a circulator according to an embodiment of the present disclosure;
[0022] Figure 6 This is a side view of a circulator according to an embodiment of the present disclosure.
[0023] Explanation of reference numerals in the attached figures:
[0024] 1. Ball screw; 10. Nut; 11. Screw; 12. Ball; 13. First helical groove; 14. Second helical groove; 15. Circulator; 16. Push rod; 151. Circulator groove; 152. Inner rim; 155. Limiting element. Detailed Implementation
[0025] To enable those skilled in the art to better understand the technical solutions of this disclosure, the technical solutions of this disclosure will be described in detail below with reference to the accompanying drawings.
[0026] Exemplary embodiments will be described more fully below with reference to the accompanying drawings; however, these exemplary embodiments may be embodied in different forms and should not be construed as limited to the embodiments set forth herein. Rather, these embodiments are provided so that this disclosure will be thorough and complete, and will enable those skilled in the art to fully understand the scope of this disclosure.
[0027] Where there is no conflict, the various embodiments of this disclosure and the features thereof in the embodiments may be combined with each other.
[0028] As used herein, the term “and / or” includes any and all combinations of one or more related enumerated entries.
[0029] The terminology used herein is for the purpose of describing particular embodiments only and is not intended to limit this disclosure. As used herein, the singular forms “a” and “the” are also intended to include the plural forms unless the context clearly indicates otherwise. It will also be understood that when the terms “comprising” and / or “made of” are used in this specification, the presence of the stated feature, integral, step, operation, element, and / or component is specified, but the presence or addition of one or more other features, integrals, steps, operations, elements, components, and / or groups thereof is not excluded.
[0030] The embodiments described herein can be described with reference to plan views and / or cross-sectional views using the ideal schematic diagrams of this disclosure. Therefore, the example illustrations can be modified according to manufacturing techniques and / or tolerances. Therefore, the embodiments are not limited to those shown in the drawings, but include modifications to configurations formed based on manufacturing processes. Therefore, the areas illustrated in the drawings are schematic in nature, and the shapes of the areas shown in the figures illustrate specific shapes of areas of an element, but are not intended to be limiting.
[0031] Unless otherwise specified, all terms used herein (including technical and scientific terms) have the same meaning as commonly understood by one of ordinary skill in the art. It will also be understood that terms such as those defined in commonly used dictionaries should be interpreted as having a meaning consistent with their meaning in the context of the relevant art and this disclosure, and will not be interpreted as having an idealized or overly formal meaning, unless expressly so defined herein.
[0032] Figure 1 This is a perspective view of a ball screw according to an embodiment of this disclosure. Figure 2 This is a perspective view of a lead screw according to an embodiment of this disclosure. Figure 3 This is a cross-sectional schematic diagram of a lead screw according to an embodiment of this disclosure. (Refer to...) Figure 1 , Figure 2 , Figure 3 The ball screw 1 includes a nut 10 and a screw 11. The outer periphery of the screw 11 includes a mounting surface and a threaded surface. The threaded surface has a first helical groove 13, while the mounting surface does not have a helical groove. This is equivalent to cutting off a portion of the original cylindrical outer periphery of the screw 11 with a complete helical groove along the axial direction to form the mounting surface. On both sides of the mounting surface, the first helical grooves 13 on the threaded surface are aligned; that is, assuming the first helical grooves 13 on both sides of the mounting surface are extended in the direction of extension of the first helical grooves 13, a complete and continuous helical groove can be formed. A circulator 15 is mounted on the mounting surface of the screw 11. Multiple circulator grooves 151 are formed on the groove surface of the circulator 15, connecting the first helical grooves 13 on both sides of the mounting surface. However, the circulator grooves 151 do not connect the first helical grooves 13 on both sides of the mounting surface in the direction of extension of the first helical grooves 13; instead, they connect two adjacent first helical grooves 13 to form a circulating raceway. Balls 12 are disposed in the circulating raceway.
[0033] With the lead screw 11 having a complete and continuous helical groove on its outer periphery, the ball 12 will roll along the helical groove from the inlet to the outlet, one revolution at a time. And... Figures 1 to 3 In the ball screw shown, the circulator channel 151 on the circulator 15 connects the adjacent first spiral channel 13. When the ball enters the circulator channel 151, it will return to the previous turn of the first spiral channel 13 along the circulator channel 151, thereby realizing the ball 12 circulating in the circulator track.
[0034] exist Figures 1 to 3 In the ball screw shown, the number of circulator channels 151 provided on the circulator 15 determines the number of circulating raceways formed on the outer periphery of the screw 11, and the balls in each circulating raceway circulate and roll in their respective circulating raceways.
[0035] like Figures 1 to 3 As shown, the nut 10 has a second helical channel 14. The first helical channel 13 and the second helical channel 14 mesh with the balls 12 to form a reverse ball screw, that is, the rotation of the nut 10 drives the screw 11 to move linearly. When the nut 10 rotates, the balls 12 circulate in the raceway, driving the screw 11 to move linearly. Figure 1As shown, one end of the lead screw 11 is connected to a push rod 16. The push rod 16 can be connected to the load. The linear motion of the lead screw 11 can drive the push rod 16 to move, thereby driving the load to move.
[0036] Figures 4 to 6 This is a schematic diagram of the structure of a circulator according to an embodiment of this disclosure. (Refer to...) Figure 4 The circulator 15 has multiple circulator channels 151, from Figure 2 As can be seen, the circulator 15 is mounted on the mounting surface of the lead screw 11, and the circulator channel 151 of the circulator 15 replaces a portion of the first helical channel 13 on the lead screw 11.
[0037] The circulator 15 of this embodiment includes a grooved surface and a connecting surface. The grooved surface is an arched surface with multiple circulator channels 151. Each circulator channel 151 has two adjacent channels connected to the first helical channel 13 on the lead screw 11 at both ends. For example, when the first channel is connected to the second channel, the ball 12, after rolling from the first channel to the second channel, should continue rolling to the third channel. However, because the first and second channels are connected, the ball 12 returns from the second channel to the first channel, thus allowing the ball 12 to circulate within 360 degrees, with each 360 degrees constituting one circulation channel. (Refer to...) Figure 4 The circulator 15 of this embodiment has three circulator channels 151. With this structure, it is unnecessary to provide a ball return channel inside the lead screw 11, and ball circulation can be performed on the outer circumferential surface of the lead screw 11. This embodiment does not specifically limit the number of circulation raceways. The number of circulator channels 151 formed on the circulator 15 is the number of circulation raceways. In some embodiments, the number of circulation raceways depends on the required dynamic load, which is proportional to the number of revolutions. In some embodiments, the number of circulation raceways depends on the load efficiency, and the number of circulation raceways is no more than 6; for example, it can be 3 or 6, which can achieve better load efficiency while meeting load requirements.
[0038] In some embodiments, refer to Figure 4 The edge of the circulator channel 151 is inwardly curved. The inwardly curved edge of the circulator channel 151 forms an inner edge 152, which extends along the direction of the groove towards the interior of the circulator channel 151. This inwardly curved edge design prevents the balls 12 rolling at high speed in the circulator channel 151 from detaching from the circulator channel 151 due to centrifugal force. With this design, there is no need to provide a return ball scraper above the circulator channel 151. In some embodiments, a return ball scraper may be provided above the circulator channel 151 to further constrain the balls 12 within the circulator channel 151.
[0039] like Figure 5 , Figure 6 As shown, the shape of the inner rim 152 matches the movement trajectory of the ball 12 as it enters the circulator channel 151. Figure 5 Taking any one of the circulator channels 151 as an example, when the ball 12 enters the circulator channel 151, under the centrifugal force, the ball 12 rolls forward along the circulator channel 151 and rolls along the left side wall of the circulator channel 151 towards the lower wall of the circulator channel 151 towards the inner edge 152. The shape of the inner edge 152 matches the above-mentioned movement trajectory of the ball 12.
[0040] In this embodiment, the circulator 15 has a centrally symmetrical structure, with any one of the circulator channels 151 being centrally symmetrical. Any port of the circulator channel 151 can serve as the entry point for the ball 12 into the circulator channel 151. Correspondingly, each of the two ports of the circulator channel 151 corresponds to an inner rim 152. The contour curve of the inner rim 152 facing the corresponding port matches the movement trajectory of the ball entering the circulator channel 151. When the ball 12 enters the circulator channel 151 along the inner rim 152, the inner rim 152 can effectively guide the ball 12 into the circulator channel 151, allowing the ball 12 to naturally mesh with the circulator channel 151. Therefore, it is not necessary to set a ball-collecting shovel at the port of the circulator channel 151.
[0041] In some embodiments, the length of the profile curve of the inner edge 152 toward the corresponding port is not less than 1 / 2 of the ball circumference. For example, the length of the profile curve of the inner edge 152 toward the corresponding port is not less than 3 / 4 of the ball circumference, ensuring that the ball 12 naturally engages with the circulator channel 151.
[0042] In this embodiment of the disclosure, the connecting surface of the circulator 15 is used to connect with the lead screw 11, thereby mounting the circulator 15 on the mounting surface of the lead screw 11.
[0043] In some embodiments, a first connecting mechanism is provided on the connecting surface of the circulator 15 for cooperating with a second connecting mechanism on the lead screw 11.
[0044] Reference Figure 3 and Figure 5 The first connecting mechanism is a limiting member 155, and a limiting groove matching the limiting member 155 is provided on the mounting surface of the lead screw 11. When the circulator 15 is installed on the lead screw 11, the limiting member 155 on the connecting surface of the circulator 15 cooperates with the limiting groove on the mounting surface of the lead screw 11, thereby fixing the circulator 15 to the lead screw 11. The limiting member 155 can be as follows: Figure 3 and Figure 5The protrusion shown can also be other types of structures, as long as it can fix the circulator 15 to the lead screw 11. For example, the limiting member 155 is interference-fitted with the limiting groove; or the limiting member 155 is inserted into the limiting groove to form a mortise and tenon structure.
[0045] In some embodiments, the first connecting mechanism may be a groove structure disposed on the connecting surface of the circulator 15, and the second connecting mechanism is a protrusion structure disposed on the mounting surface of the lead screw 11, wherein the groove structure and the protrusion structure are connected in cooperation.
[0046] The material of the circulator 15 is not specifically limited in this embodiment. For example, the circulator can be made of metal, resin, plastic, or other materials.
[0047] The present disclosure does not impose any special limitations on the manufacturing process of the circulator 15. For example, the circulator 15 can be manufactured by molding processes including but not limited to injection molding, casting, powder metallurgy, 3D printing, etc.
[0048] In some embodiments, the circulator 15 can be made of plastic, formed by injection molding. This allows for manufacturing with a simple process. Furthermore, the lower cost of plastic helps reduce the cost of the ball screw.
[0049] In this embodiment, only the mounting surface needs to be machined on the lead screw 11, without the need to open a ball return channel inside the lead screw 11. The structure of the mounting surface is simple and easier to machine, which helps to reduce the machining difficulty of the lead screw 11.
[0050] The following is combined Figures 1 to 3 A ball screw according to an embodiment of this disclosure will be further described.
[0051] like Figures 1 to 3 As shown, the ball screw 1 includes a nut 10, a screw 11, and balls 12. The screw 11 has a first helical groove 13, and the nut 10 has a second helical groove 14. The first helical groove 13 and the second helical groove 14 cooperate with each other. A circulator 15 is provided on the screw 11.
[0052] The outer periphery of the lead screw 11 includes a mounting surface and a threaded surface, with the first helical groove 13 disposed on the threaded surface. The connecting surface of the circulator 15 is fitted to the mounting surface of the lead screw 11, and the groove surface of the circulator 15 matches the outer periphery of the threaded surface. That is, after the circulator 15 is installed on the mounting surface of the lead screw 11, the groove surface of the circulator 15 and the threaded surface of the lead screw 11 are on the same cylindrical surface, thereby ensuring that the lead screw 11 with the circulator 15 installed can be assembled in the nut 10. The circulator groove 151 provided on the groove surface of the circulator 15 connects two adjacent first helical grooves 13 on the threaded surface to form a circulating raceway; the ball 12 is disposed in the circulating raceway.
[0053] In some embodiments, such as Figures 1 to 3 As shown, the connecting surface of the circulator 15 is a plane, and a first connecting mechanism is provided on the connecting surface; the mounting surface of the lead screw 11 is a plane that matches the connecting surface, and a second connecting mechanism is provided on the mounting surface; the first connecting mechanism and the second connecting mechanism cooperate to connect, thereby mounting the circulator 15 on the mounting surface of the lead screw 11.
[0054] In this embodiment, the first connecting mechanism and the second connecting mechanism can be connected by means of bolts, adhesive, clips, pins, etc. This embodiment does not impose any special limitations on this.
[0055] In some embodiments, the first connecting mechanism includes a limiting member 155 protruding from the connecting surface of the circulator 15; the second connecting mechanism includes a limiting groove disposed on the mounting surface of the lead screw 11; the limiting member 155 is engaged with the limiting groove. In some embodiments, the limiting member 155 and the limiting groove are interference-fitted. In some embodiments, the limiting member 155 and the limiting groove are inserted into each other to form a mortise and tenon structure.
[0056] In some embodiments, the first connecting mechanism is a groove structure provided on the connecting surface of the circulator 15, and the second connecting mechanism is a protrusion structure provided on the mounting surface of the lead screw 11. The groove structure and the protrusion structure are interference-fitted or plug-fitted to mount the circulator 15 on the mounting surface of the lead screw 11.
[0057] This disclosure provides an electric cylinder, which includes a ball screw 1 and a driver provided in this disclosure, and the driver drives the ball screw 1 to run.
[0058] The circulator according to the embodiments of this disclosure has a simple structure, can reduce the size of components, and can be manufactured using simple molds such as coreless casting molds, thus achieving a compact circulation system. The circulator of the embodiments of this disclosure can be applied to application scenarios where the ball screw size is small, achieving compactness of the circulator and ball screw, reducing machining difficulty, and improving machining accuracy.
[0059] Example embodiments have been disclosed herein, and while specific terminology has been used, it is for illustrative purposes only and should be construed as such, and is not intended to be limiting. In some instances, it will be apparent to those skilled in the art that features, characteristics, and / or elements described in connection with particular embodiments may be used alone, or in combination with features, characteristics, and / or elements described in connection with other embodiments, unless otherwise expressly indicated. Therefore, those skilled in the art will understand that various changes in form and detail may be made without departing from the scope of this disclosure as set forth by the appended claims.
Claims
1. A circulator, characterized in that, The circulator (15) includes a groove surface and a connecting surface, the groove surface being an arched surface; multiple circulator channels (151) extending in the circumferential direction are opened on the groove surface; one circulator channel (151) is used to connect two adjacent channels on the lead screw. The connecting surface is used to connect with the lead screw to install the circulator (15) on the lead screw.
2. The circulator according to claim 1, characterized in that, The edge of the circulator channel (151) bends inward to form an inner rim (152), which extends along the direction of the groove facing the interior of the circulator channel (151).
3. The circulator according to claim 2, characterized in that, The shape of the inner rim (152) matches the movement trajectory of the ball as it enters the circulator channel (151).
4. The circulator according to claim 3, characterized in that, The two ports of the circulator channel (151) each correspond to an inner rim (152); the inner rim (152) is oriented toward the contour curve corresponding to the port and matches the movement trajectory of the ball entering the circulator channel (151).
5. The circulator according to claim 4, characterized in that, The length of the contour curve of the inner edge (152) toward the corresponding port is not less than 1 / 2 of the circumference of the ball.
6. The circulator according to any one of claims 1 to 5, characterized in that, The connecting surface is a plane, and a first connecting mechanism is provided on the connecting surface.
7. The circulator according to claim 6, characterized in that, The first connecting mechanism includes a limiting member (155) protruding from the connecting surface.
8. The circulator according to any one of claims 1 to 5, characterized in that, The material of the circulator (15) includes any one of plastic, resin, and metal.
9. A ball screw, comprising a nut (10), a screw (11), and balls, characterized in that, The ball screw (1) further includes a circulator (15) according to any one of claims 1 to 8; The outer periphery of the lead screw (11) includes a mounting surface and a threaded surface, and a groove is provided on the threaded surface; the connecting surface of the circulator (15) is connected to the mounting surface, and the groove surface of the circulator (15) matches the outer periphery of the threaded surface; the circulator groove (151) provided on the groove surface of the circulator (15) connects two adjacent grooves on the threaded surface to form a circulating raceway; The balls are disposed in the circulating raceway.
10. The ball screw according to claim 9, characterized in that, The connecting surface is a plane, and a first connecting mechanism is provided on the connecting surface; the mounting surface is a plane that matches the connecting surface, and a second connecting mechanism is provided on the mounting surface; the first connecting mechanism and the second connecting mechanism cooperate to connect.
11. The ball screw according to claim 10, characterized in that, The first connecting mechanism includes a limiting member (155) protruding from the connecting surface; the second connecting mechanism includes a limiting groove disposed on the mounting surface; the limiting member (155) is engaged with the limiting groove.
12. An electric cylinder comprising a driver and a ball screw (1) according to any one of claims 9 to 11, the driver driving the ball screw (1) to operate.