Roller, manufacturing method thereof and planetary roller screw

Abstract

The invention provides a roller, a manufacturing method of the roller and a planetary roller lead screw. The roller comprises a roller body, a roller thread arranged on the outer side face of the roller body and two roller gears, and the roller thread is located between the two roller gears; and the pin rollers are made of plastics. The planetary roller screw solves the problem that an existing planetary roller screw is high in manufacturing cost and weight.

Description

Technical Field

[0001] The present application relates to the technical field of planetary roller screws, and in particular to a roller and a manufacturing method thereof, and a planetary roller screw. Background Art

[0002] A planetary roller screw is a transmission component that converts rotational motion into linear motion. It boasts advantages such as high operating speed, strong load capacity, good environmental adaptability, and a long service life, and boasts broad application prospects. A planetary roller screw generally consists of a screw, a nut, several rollers positioned within the nut, and an internal gear ring fixed to each end of the nut. The screw, nut, and rollers are all machined from metal materials, and the large number of rollers makes the machining process complex. For consumer or light-load industries, using existing planetary roller screws would undoubtedly increase costs and the overall weight of the equipment using them. Summary of the Invention

[0003] The embodiments of the present application provide a roller and a manufacturing method thereof, and a planetary roller screw, which solve the problem of relatively high manufacturing cost and weight of existing planetary roller screws.

[0004] The present application is implemented as follows: a roller is used for a planetary roller screw, including a roller body, a roller thread and two roller gears arranged on the outer side of the roller body, and the roller thread is located between the two roller gears; the material of the roller is plastic.

[0005] In some embodiments, the top circle diameter of the roller gear is smaller than the minor diameter of the roller thread.

[0006] In some embodiments, the difference between the addendum diameter of the roller gear and the minor diameter of the roller thread is greater than or equal to 0.1 mm.

[0007] In some embodiments, the diameter of the tooth top circle of the roller gear is equal to the major diameter of the roller thread.

[0008] In some embodiments, the roller body is cylindrical.

[0009] In some embodiments, the roller body, the roller thread, and the roller gear are an integrated structure.

[0010] The present application also provides a planetary roller screw, comprising a screw, a nut, an inner gear ring, a plurality of rollers as described in any of the above embodiments, and a roller retainer, wherein the screw has an external screw thread; the nut surrounds and is coaxial with the screw, and the nut has an internal nut thread; the inner gear ring is arranged in the nut, and the inner gear ring has an internal gear; a plurality of the rollers are located between the screw and the inner gear ring, the roller thread is engaged with the external screw thread, the roller thread is engaged with the inner nut thread, and the roller gear is engaged with the internal gear; the roller retainer is arranged inside the nut, and the roller retainer is provided with a screw through hole and a roller fixing hole, the screw is inserted into the screw through hole, and the end of the roller is inserted into the roller fixing hole.

[0011] In some embodiments, the screw rod is made of plastic.

[0012] In some embodiments, the nut is made of plastic.

[0013] The present application also provides a method for manufacturing a roller, which is used to manufacture the roller as described above, comprising the following steps:

[0014] Mounting a main mold assembly on an injection molding machine, wherein a first injection molding cavity is formed in the main mold assembly for forming a portion of the roller body and the roller thread;

[0015] The first side mold assembly and the second side mold assembly are installed on the injection molding machine and aligned on both sides of the main mold assembly to form the remaining portion of the roller body and the two roller gears. The second injection molding cavity in the first side mold assembly, the third injection molding cavity in the second side mold assembly, and the first injection molding cavity are connected;

[0016] Injecting plastic into the first injection molding cavity, the second injection molding cavity, and the third injection molding cavity to form the roller;

[0017] The main mold assembly, the first side mold assembly and the second side mold assembly are removed, and the roller is taken out.

[0018] In some embodiments, the main mold assembly includes an upper mold assembly and a lower mold assembly, and the step of installing the main mold assembly on the injection molding machine includes:

[0019] Installing the upper mold device and the lower mold device on the injection molding machine and aligning them up and down to form the main mold device;

[0020] The method of removing the main mold assembly, the first side mold assembly, and the second side mold assembly to remove the roller comprises the following steps:

[0021] separating the first side mold assembly from the main mold assembly;

[0022] separating the second side mold assembly from the main mold assembly;

[0023] Separating the upper mold device from the lower mold device after injection molding;

[0024] Remove the roller from the lower die assembly.

[0025] In some embodiments, removing the main mold assembly, the first side mold assembly, and the second side mold assembly to remove the roller comprises the following steps:

[0026] Rotating the main mold assembly around the central axis of the roller to eject the second side mold assembly and separate the main mold assembly from the roller, wherein the tooth top circle diameter of the roller gear is smaller than the minor diameter of the roller thread;

[0027] Remove the roller from the first side mold assembly.

[0028] The present application also provides a method for manufacturing a roller, which is used to manufacture the roller as described in the above embodiment, comprising the following steps:

[0029] Mounting a main mold device on an injection molding machine, wherein a fourth injection molding cavity is formed in the main mold device for injection molding the roller body and the roller thread;

[0030] Injecting an injection molding material into the fourth injection molding cavity to form a roller to be processed, wherein the roller to be processed has a roller thread;

[0031] The roller to be processed is taken out from the fourth injection molding cavity, and a roller gear is processed on the roller to be processed to obtain the roller.

[0032] In some embodiments, the main mold assembly includes an upper mold assembly and a lower mold assembly, and the step of installing the main mold assembly on the injection molding machine includes:

[0033] Installing the upper mold device and the lower mold device on the injection molding machine and aligning them up and down to form the main mold device;

[0034] The process of removing the roller to be processed from the fourth injection molding cavity and processing a roller gear on the roller to be processed to obtain the roller comprises the following steps:

[0035] Separating the upper mold device from the lower mold device after injection molding;

[0036] Taking out the roller to be processed from the lower die device;

[0037] Installing a first side mold assembly and a second side mold assembly on an injection molding machine, wherein the first side mold assembly and the second side mold assembly are used to form the roller gear;

[0038] Inserting the roller to be processed into the first side mold device and the second side mold device along both ends of its axis, respectively, so that the space between the roller to be processed and the first side mold device forms a fifth injection cavity, and the space between the roller to be processed and the second side mold device forms a sixth injection cavity;

[0039] Injecting plastic into the fifth injection molding cavity and the sixth injection molding cavity to form roller gears;

[0040] The first side mold assembly and the second side mold assembly are removed to obtain the roller.

[0041] In some embodiments, the main mold assembly includes an upper mold assembly and a lower mold assembly, and the step of installing the main mold assembly on the injection molding machine includes:

[0042] Installing the upper mold device and the lower mold device on the injection molding machine and aligning them up and down to form the main mold device;

[0043] The process of removing the roller to be processed from the fourth injection molding cavity and processing a roller gear on the roller to be processed to obtain the roller comprises the following steps:

[0044] Separating the upper mold device from the lower mold device after injection molding;

[0045] Taking out the roller to be processed from the lower die device;

[0046] Roller gears are machined on roller threads at both ends of the roller to be machined along its axis to obtain the roller.

[0047] In some embodiments, removing the roller to be processed from the fourth injection molding cavity and processing a roller gear on the roller to be processed to obtain a roller comprises the following steps:

[0048] Rotating the main mold device around the central axis of the roller to be processed to separate the roller to be processed from the main mold device;

[0049] Roller gears are machined on roller threads at both ends of the roller to be machined along its axis to obtain the roller.

[0050] The present application also provides a method for manufacturing a roller, which is used to manufacture the roller as described above, comprising the following steps:

[0051] Installing the upper mold assembly and the lower mold assembly on the injection molding machine;

[0052] The upper mold device and the lower mold device are aligned relative to each other, and the space between the aligned upper mold device and the lower mold device forms a seventh injection cavity for forming the roller;

[0053] Injecting plastic into the seventh injection molding cavity to form the roller;

[0054] Separating the upper mold device from the lower mold device after injection molding;

[0055] Remove the roller from the lower die assembly.

[0056] The beneficial effects of a roller, a manufacturing method thereof, and a planetary roller screw provided by the present application are: compared with the existing technology, the present application uses plastic to manufacture the roller body and forms the roller thread through injection molding. Compared with the existing technology that uses metal materials to manufacture rollers and adopts mechanical processing to make roller threads and roller gears, the weight of the roller is greatly reduced, and the manufacturing cost of the roller is also reduced, making the roller of the embodiment of the present application more suitable for application in the consumer electronics industry or light load industry. BRIEF DESCRIPTION OF THE DRAWINGS

[0057] Figure 1 This is a schematic structural diagram of a planetary roller screw provided by the present application;

[0058] Figure 2 is a cross-sectional view of a planetary roller screw provided by the present application;

[0059] Figure 3 It is a structural schematic diagram of a roller provided by this application;

[0060] Figure 3-1 yes Figure 1 The main view;

[0061] Figure 4 It is a schematic structural diagram of another roller provided by the present application;

[0062] Figure 5 This is a structural diagram of another roller provided by the present application;

[0063] Figure 6 This is a schematic flow chart of a method for manufacturing a roller provided by the present application;

[0064] Figure 7 yes Figure 6 The specific process of step S104 is shown in FIG. Figure 1 ;

[0065] Figure 7-1 yes Figure 6 Implementation diagram of step S104;

[0066] Figure 8yes Figure 6 The specific process of step S104 is shown in FIG. Figure 2 ;

[0067] Figure 9 is a schematic flow chart of another method for manufacturing a roller provided by the present application;

[0068] Figure 10 yes Figure 9 Specific process diagram of step S903 Figure 1 ;

[0069] Figure 10-1 yes Figure 10 A schematic diagram of the structure of the roller to be processed obtained after step S1002 is completed;

[0070] Figure 11 yes Figure 9 Specific process diagram of step S903 Figure 2 ;

[0071] Figure 11-1 yes Figure 11 A schematic diagram of the structure of the roller to be processed obtained after step S1102 is completed;

[0072] Figure 12 yes Figure 9 Specific process diagram of step S903 Figure 3 ;

[0073] Figure 13 This is a flow chart of another method for manufacturing a roller provided in this application.

[0074] Figure markings: 1. Screw; 11. External screw thread; 2. Nut; 21. Internal nut thread; 3. Internal ring gear; 31. Internal gear; 4. Roller; 41. Roller body; 42. Roller thread; 43. Roller gear; 5. Roller cage; 51. Screw through hole; 52. Roller fixing hole; 61. Upper mold device; 62. Lower mold device; 63. First side mold device; 64. Second side mold device. DETAILED DESCRIPTION

[0075] In order to make the purpose, technical solutions and advantages of this application more clearly understood, the present application is further described in detail below with reference to the accompanying drawings and embodiments. It should be understood that the specific embodiments described herein are only used to explain this application and are not intended to limit this application.

[0076] It should be noted that when an element is referred to as being “fixed on” or “disposed on” another element, it may be directly on the other element or indirectly on the other element. When an element is referred to as being “connected to” another element, it may be directly connected to the other element or indirectly connected to the other element.

[0077] It should be understood that the terms "length", "width", "up", "down", "front", "back", "left", "right", "vertical", "horizontal", "top", "bottom", "inside", "outside", etc., indicating the orientation or position relationship, are based on the orientation or position relationship shown in the accompanying drawings, and are only for the convenience of describing this application and simplifying the description, and do not indicate or imply that the device or element referred to must have a specific orientation, be constructed and operated in a specific orientation, and therefore cannot be understood as a limitation on this application.

[0078] Furthermore, the terms "first" and "second" are used for descriptive purposes only and should not be construed as indicating or implying relative importance or implicitly specifying the number of the technical features being referred to. Thus, a feature defined as "first" or "second" may explicitly or implicitly include one or more of the features. Throughout the description of this application, "plurality" means two or more, unless otherwise specifically defined.

[0079] It should also be noted that, in the embodiments of the present application, the same figure mark is used to represent the same component or the same part. For the same parts in the embodiments of the present application, the figure may only mark the figure with one of the parts or components as an example. It should be understood that the figure mark is also applicable to other identical parts or components.

[0080] The embodiments of the present application provide a roller and a manufacturing method thereof, and a planetary roller screw, which solve the problem of relatively high manufacturing cost and weight of existing planetary roller screws.

[0081] refer to Figure 1 and Figure 2 An embodiment of the present application provides a planetary roller screw, including a screw rod 1, a nut 2, an inner ring 3, a plurality of rollers 4 and a roller cage 5.

[0082] Among them, the screw 1 has an external screw thread 11; the nut 2 surrounds and is coaxial with the screw 1, and the nut 2 has an internal nut thread 21; the inner ring gear 3 is arranged in the nut 2, and the inner ring gear 3 has an internal gear 31; multiple rollers 4 are located between the screw 1 and the inner ring gear 3, the roller thread 42 of the roller 4 is engaged with the external screw thread 11, the roller thread 42 is engaged with the internal nut thread 21, and the roller gear 43 of the roller 4 is engaged with the internal gear 31; the roller cage 5 is arranged inside the nut 2, and the roller cage 5 is provided with a screw through hole 51 and a roller fixing hole 52, the screw 1 is inserted into the screw through hole 51, and the end of the roller 4 is inserted into the roller fixing hole 52, and the roller 4 is made of plastic material.

[0083] A planetary roller screw, also known as a planetary roller screw or satellite roller screw, is a low-friction, precision screw-type drive. It is a mechanical device that converts rotary motion into linear motion or vice versa. Planetary roller screws are used as actuators in many electromechanical linear actuators. They are suitable for applications requiring high precision, high speed, heavy-duty, durable, and heavy-duty use.

[0084] A roller screw is a mechanical transmission device similar to a ball screw, in which rollers are used as load transfer elements between the nut 2 and the screw instead of balls. The rollers are usually threaded, but can also be grooved depending on the type of spiral roller. Within a given volume, roller screws have more footholds than ball screws, and for a given rated load, roller screws can be more compact while still providing similar efficiency (75%-90%) at medium and low speeds, and maintaining relatively high efficiency at high speeds. Roller screws are superior to ball screws in positioning accuracy, rated load, stiffness, speed, acceleration and service life. Standard roller screw drives can achieve dynamic load capacities exceeding 130 tons of force (single drive capacity exceeds hydraulic cylinders).

[0085] The specific transmission process of the planetary roller screw can be decomposed into: ① Input rotational motion: The driving source (such as a motor) drives the screw to rotate. ② Rotation of screw 1: The outer screw thread 11 of screw 1 engages with the roller thread 42 of roller 4. ③ Movement of roller 4: Roller 4 revolves around screw 1 and rotates on its own axis. ④ Linear motion of nut 2: The roller thread 42 of roller 4 engages with the inner nut thread 21 of nut 2, pushing the nut 2 to move along the axis of screw 1. ⑤ Load transfer: Multiple rollers 4 evenly share the load to ensure high load-bearing capacity. ⑥ Output linear motion: The linear motion of nut 2 is transmitted to the external load.

[0086] Planetary roller screws have the characteristics of high precision (rolling contact of planetary rollers reduces friction and backlash, ensuring high precision); high load (multiple planetary rollers evenly share the load, with strong load-bearing capacity); high efficiency (rolling friction reduces energy loss and high transmission efficiency); and long life (uniform load distribution and rolling contact reduce wear and extend service life).

[0087] Existing roller screws are generally made of metal, which provides a certain degree of rigidity and precision. However, using metal to make roller screws makes the production cost of the roller screw extremely high, and the entire roller screw is also very heavy. Due to the wide range of applications of roller screws, expensive and heavy roller screws are not suitable for use in the consumer electronics industry and light load industries. Therefore, the embodiment of the present application uses a plastic material to make the roller 4. Compared with rollers 4 made of metal materials, not only is the weight reduced, but the material cost is also reduced.

[0088] It should be noted that reducing the manufacturing cost of the roller screw can be achieved by reducing the manufacturing cost of each component included in the roller screw, that is, reducing the manufacturing cost of key components included in the roller screw, such as the screw rod 1, nut 2, and roller 4. In the embodiment of the present application, the roller 4 is made of a plastic material. Since there are multiple rollers 4, the manufacturing cost of the roller 4 can be reduced, thereby reducing the manufacturing cost of the planetary roller screw. Compared with rollers 4 made of metal materials, rollers 4 made of plastic materials can not only reduce the manufacturing cost, but also reduce the weight of rollers 4, thereby reducing the weight of the planetary roller screw.

[0089] In some embodiments, in addition to using plastic material to make the rollers 4, the screw rod 1 can also be made of plastic material, which can further reduce the production cost and weight of the planetary roller screw.

[0090] In some embodiments, in order to further reduce the manufacturing cost and weight of the planetary roller screw, the nut 2 may also be made of plastic material.

[0091] refer to Figure 3 The roller 4 provided in the embodiment of the present application includes a roller body 41, a roller thread 42 and two roller gears 43 provided on the outer side of the roller body 41, and the roller thread 42 is located between the two roller gears 43; the material of the roller is plastic.

[0092] It should be noted that the roller thread 42 and the two roller gears 43 are arranged on the outer side of the roller body 41. It can be understood that the roller thread 42 and the roller gears 43 are directly formed on the roller body 41. The entire roller 4 is an integrated structure. The roller body 41 is made of plastic, and the roller thread 42 is formed by injection molding. Compared with the prior art in which the roller 4 is obtained by machining metal materials, the embodiment of the present application can reduce the overall production cost of the roller 4, and the characteristics of the plastic material can also reduce the overall weight of the roller 4. In this way, the planetary roller screw using the roller 4 of the embodiment of the present application can be used in the consumer electronics industry or the light load industry without causing problems of excessive cost and excessive weight, and is more suitable for the consumer electronics industry or the light load industry.

[0093] In the embodiment of the present application, the roller gear 43 can be injection molded simultaneously with the roller thread 42. This allows the roller 4 to be molded in a single pass using the same injection molding material, significantly improving the production efficiency of the roller 4. Alternatively, the roller thread 42 can be injection molded first, followed by machining to form the roller gear 43. The above two methods can be freely selected based on actual circumstances and are not specifically limited in the present embodiment.

[0094] When the roller thread 42 and the roller gear 43 are both formed by injection molding, different injection molds can be used to simultaneously form the roller thread 42 and the roller gear 43 , and a demoulding operation needs to be performed after the molding is completed.

[0095] In some embodiments, demoulding can be achieved by rotating the injection mold corresponding to the roller thread 42 relative to the roller 4.

[0096] In some embodiments, reference Figure 3-1 The tooth top circle diameter of the roller gear 43 is smaller than the minor diameter of the roller thread 42 .

[0097] It should be noted that, during the above-mentioned rotary demolding process, the injection mold corresponding to the roller thread 42 will pass through the outer periphery of the roller gear 43. In the embodiment of the present application, the tooth top circle diameter of the roller gear 43 is smaller than the minor diameter of the roller thread 42, so that the injection mold for injection molding the roller thread 42 will not contact the roller gear 43 during the rotary demolding process, and will not cause damage to the roller gear 43.

[0098] It can be understood that a thread refers to a continuous raised portion with a specific cross-section and in a spiral shape made on the surface of a cylindrical or conical mother body. Threads are divided into cylindrical threads and conical threads according to the shape of their mother body; they are divided into external threads and internal threads according to their position on the mother body; and they are divided into triangular threads, rectangular threads, trapezoidal threads, serrated threads and other special-shaped threads according to their cross-sectional shape (tooth profile). Threads have a major diameter (outer diameter), a middle diameter, and a minor diameter (inner diameter). The major diameter refers to the diameter of an imaginary cylinder that coincides with the top of the external thread or the bottom of the internal thread. The nominal diameter of a thread is the major diameter. The minor diameter refers to the diameter of an imaginary cylinder that coincides with the bottom of the external thread or the top of the internal thread. The middle diameter refers to the diameter of an imaginary cylinder with equal widths when the main line passes through the protrusions and grooves on the tooth profile.

[0099] A gear is a mechanical component with teeth on its rim that mesh continuously to transmit motion and power. The tip circle is the circle where the top of the tooth is located.

[0100] When the roller thread 42 and the roller gear 43 are both formed by injection molding, different injection molds can be used at the same time to injection mold the roller thread 42 and the roller gear 43. After the processing is completed, demolding is required. For example, a split mold combination can be used to form an injection mold for the injection-molded roller thread 42. In this way, when demolding, it is only necessary to separate the split mold from the roller 4 to achieve demolding. In this way, there is no need to limit the dimensional parameters of the roller gear 43 and the dimensional parameters of the roller thread 42, and it is also more convenient and quick to demold.

[0101] Based on this, when demoulding by directly separating the split mold, refer to Figure 3-1The tooth top circle diameter d of the roller gear 43 may be smaller than the minor diameter D1 of the roller thread 42, and the difference between the tooth top circle diameter d of the roller gear 43 and the minor diameter D1 of the roller thread 42 is greater than or equal to 0.1 mm. Figure 4 The tooth top circle diameter d of the roller gear 43 may also be equal to the major diameter D2 of the roller thread 42. This embodiment of the present application does not make any specific limitation.

[0102] In the embodiment of the present application, when different molds are used to simultaneously inject the roller thread 42 and the roller gear 43, the straight-toothed roller gear 43 can be directly injection-molded, that is, Figure 3 and Figure 4 Of course, the roller threads 42 can also be formed by injection molding first. In this case, the roller threads 42 are distributed on the entire outer side of the roller body 41, and then the roller gears 43 are formed by machining on the roller threads 42 at both ends of the roller body 41 along its axis. Figure 5 The roller gear 43 shown in FIG. 4 can also play a corresponding role.

[0103] In some embodiments, the roller body 41 is cylindrical, so that the roller body 41 is more compatible with the shapes of the roller thread 42 and the roller gear 43, and it is more convenient to manufacture the roller gear 43 by machining.

[0104] In some embodiments, the roller body 41, the roller thread 42, and the roller gear 43 are an integrated structure. This allows the roller to be integrally formed through an injection molding process, greatly improving the production efficiency of the roller.

[0105] refer to Figure 6 The present application provides a method for manufacturing a roller, which is used to manufacture the roller 4 as described above, comprising the following steps:

[0106] S101 , installing a main mold device on an injection molding machine, wherein a first injection molding cavity is formed in the main mold device for forming a portion of the roller body 41 and the roller thread 42 .

[0107] S102. Install the first side mold device 63 and the second side mold device 64 on the injection molding machine and align them on both sides of the main mold device to form the remaining part of the roller body 41 and the two roller gears 43. The second injection cavity in the first side mold device 63, the third injection cavity in the second side mold device 64 and the first injection cavity are connected.

[0108] The partial roller body 41 formed by the first injection cavity in the above step S101 and the remaining part of the roller body 41 formed by the first side mold device 63 and the second side mold device 64 in step S102 together constitute the complete roller body 41.

[0109] It should be noted that the first side mold device 63 has a second injection cavity, and the second injection cavity is used to adapt to the roller gear 43. The second side mold device 64 has a third injection cavity, and the third injection cavity is the same as the second injection cavity, and is also used to adapt to the roller gear 43. The cavity formed by connecting the first injection cavity, the second injection cavity and the third injection cavity is adapted to the roller 4.

[0110] S103 , injecting plastic into the first injection molding cavity, the second injection molding cavity, and the third injection molding cavity to form a roller 4 .

[0111] It should be noted that, since the first injection cavity, the second injection cavity and the third injection cavity are connected, the injection molding material is injected into the first injection cavity, the second injection cavity and the third injection cavity, and the roller 4 is formed after the injection molding material is solidified.

[0112] S104, remove the main mold assembly, the first side mold assembly 63 and the second side mold assembly 64, and take out the roller 4.

[0113] It should be noted that the roller 4 manufactured by the above-mentioned method of manufacturing a roller can not only be obtained by integrally forming and injection molding the roller 4, thereby improving the manufacturing efficiency of the roller 4 and ensuring the manufacturing accuracy of the roller 4, but also the roller 4 is obtained by plastic injection molding, which can greatly reduce the manufacturing cost of the roller 4 and reduce the weight of the roller 4, making it more suitable for application in the consumer electronics industry or the light load industry.

[0114] The above step S104 can be implemented in various ways, specifically:

[0115] The main mold assembly includes an upper mold assembly 61 and a lower mold assembly 62. The above step S101 specifically involves installing the upper mold assembly 61 and the lower mold assembly 62 on the injection molding machine and aligning them to form the main mold assembly.

[0116] On this basis, reference Figure 7 The above step S104 can be implemented by implementation method 1, which specifically includes the following steps:

[0117] S701, separating the first side mold assembly 63 from the main mold assembly.

[0118] S702, separating the second side mold assembly 64 from the main mold assembly.

[0119] S703 , separating the upper mold assembly 61 and the lower mold assembly 62 after injection molding.

[0120] S704 , remove the roller 4 from the lower mold device 62 .

[0121] The first method of implementing step S104 can be understood as removing the upper mold device 61, the lower mold device 62, the first side mold device 63 and the second side mold device 64 that are independently provided. For details, please refer to Figure 7-1 A simplified diagram of the removal of the upper mold assembly 61, lower mold assembly 62, first side mold assembly 63, and second side mold assembly 64 is shown. This method does not significantly limit the dimensional parameters of the roller thread 42 and roller gear 43 of the roller 4. In other words, regardless of whether the addendum diameter of the roller gear 43 of the roller 4 is smaller than the minor diameter of the roller thread 42, or whether the addendum diameter of the roller gear 43 of the roller 4 is equal to the minor diameter of the roller thread 42, the above-described method 1 can be used to implement step S104 without damaging the roller gear 43 or the roller thread 42.

[0122] refer to Figure 8 The above step S104 can be implemented by implementation method 2, which specifically includes the following steps:

[0123] S801, the main mold assembly is rotated around the central axis of the roller 4 to eject the second side mold assembly 64, and the main mold assembly is separated from the roller 4.

[0124] It should be noted that the implementation of the above step S801 needs to meet the requirement that the diameter of the tooth top circle of the roller gear 43 is smaller than the minor diameter of the roller thread 42 .

[0125] S802, remove the roller 4 from the first side mold device 63.

[0126] The second method for implementing step S104 can be understood as rotating the main mold assembly formed by the upper mold assembly 61 and the lower mold assembly 62 relative to the roller 4. During the main mold assembly's rotation, the second side mold assembly 64 is ejected, that is, the second side mold assembly 64 is removed. The main mold assembly is then rotated again until the main mold assembly is free of the roller 4. During this process, the upper mold assembly 61, the lower mold assembly 62, and the second side mold assembly 64 can be removed simply by rotating the main mold assembly. Finally, the roller 4 can be directly removed from the first side mold assembly 63, greatly improving the demolding efficiency of the roller 4 after the roller 4 is formed by injection molding.

[0127] It should be noted that implementing step S104 through the above-mentioned method 2 requires certain requirements for the dimensional parameters of the roller thread 42 and the roller gear 43 of the roller 4. Specifically, the top circle diameter of the roller gear 43 of the roller 4 is smaller than the minor diameter of the roller thread 42. In this way, when the main mold device rotates to a position on the outer periphery of the roller gear 43, the main mold device will not contact the roller gear 43 and will not cause damage to the roller gear 43.

[0128] refer to Figure 9The present application provides a method for manufacturing a roller, which is used to manufacture the roller 4 as described above, comprising the following steps:

[0129] S901 , installing a main mold assembly on an injection molding machine, wherein the main mold assembly forms a fourth injection molding cavity for forming a roller body 41 and a roller thread 42 .

[0130] S902 , injecting plastic into the fourth injection molding cavity to form a roller to be processed, wherein the roller to be processed has a roller thread 42 .

[0131] S903, taking out the roller to be processed from the fourth injection molding cavity, and processing the roller gear 43 on the roller to be processed to obtain the roller 4.

[0132] It should be noted that by using the aforementioned roller manufacturing method to manufacture roller 4, roller thread 42 and roller gear 43 can be manufactured separately, which improves the manufacturing precision of roller 4. Furthermore, the dimensional parameters of roller thread 42 and roller gear 43 can be tailored to meet different application requirements, greatly expanding the application range of roller 4. Furthermore, using plastic injection molding to manufacture the roller significantly reduces the manufacturing cost and weight of roller 4, making roller 4 more suitable for applications in the consumer electronics industry or light-load industries.

[0133] The above step S903 can be implemented in various ways, specifically:

[0134] The main mold assembly includes an upper mold assembly 61 and a lower mold assembly 62. The above step S101 specifically involves installing the upper mold assembly 61 and the lower mold assembly 62 on the injection molding machine and aligning them to form the main mold assembly.

[0135] On this basis, reference Figure 10 The above step S903 can be implemented by implementation method 1, which specifically includes the following steps:

[0136] S1001 , separating the upper mold assembly 61 and the lower mold assembly 62 after injection molding.

[0137] S1002, taking out the roller to be processed from the lower die device 62.

[0138] refer to Figure 10-1 , Figure 10-1 This is a schematic diagram of the structure of the roller to be processed after step S1002. It should be noted that the roller to be processed comprises only the roller body 41 and the roller threads 42 provided on the roller body 41, without the roller gear 43. Therefore, it is necessary to first separate the upper mold assembly 61 from the lower mold assembly 62 before removing the roller to be processed from the lower mold assembly 62 to avoid damaging the roller threads 42 formed by injection molding.

[0139] S1003 , installing the first side mold device 63 and the second side mold device 64 on the injection molding machine. The first side mold device 63 and the second side mold device 64 are used to form the roller gear 43 .

[0140] S1004. Insert the roller to be processed into the first side mold device 63 and the second side mold device 64 along the two ends of its axis respectively. The space between the roller to be processed and the first side mold device 63 forms the fifth injection cavity, and the space between the roller to be processed and the second side mold device 64 forms the sixth injection cavity.

[0141] S1005 , injecting plastic into the fifth and sixth injection molding cavities to form roller gears 43 .

[0142] It should be noted that because the roller to be processed is inserted into the fifth and sixth injection molding cavities at both ends along its axis, the plastic injected into the fifth and sixth molding cavities, after solidification, forms roller gears 43 at both ends of the roller to be processed along its axis. Thus, the roller gears 43 and the roller to be processed form a single unit, namely, roller 4. This entire roller 4 is formed by injection molding, which not only reduces manufacturing costs but also reduces the weight of roller 4.

[0143] S1006. Remove the first side mold device 63 and the second side mold device 64 to obtain the roller 4.

[0144] refer to Figure 11 The above step S903 can be implemented by implementation method 2, which specifically includes the following steps:

[0145] S1101 , separating the upper mold device 61 and the lower mold device 62 after injection molding.

[0146] S1102, taking out the roller to be processed from the lower die device 62.

[0147] refer to Figure 11-1 , Figure 11-1 FIG4 is a schematic diagram of the structure of the roller to be processed after step S1102. It should be noted that the roller to be processed comprises only the roller body 41 and the roller threads 42 provided on the roller body 41, without the roller gear 43. Furthermore, the roller threads 42 on the roller body 41 are also distributed at both ends of the roller body 41 along its axis.

[0148] S1103 , machining roller gears 43 on the roller threads 42 at both ends of the roller to be processed along its axis to obtain roller 4 .

[0149] The structural diagram of the roller 4 obtained after the above step S1103 is completed can be referred to Figure 5 .

[0150] The roller 4 obtained by the above method is entirely made of plastic material, which not only reduces the manufacturing cost but also reduces the weight of the roller 4.

[0151] refer to Figure 12 The above step S903 can be implemented by implementation method 3, which specifically includes the following steps:

[0152] S1201, rotating the main mold device around the central axis of the roller to be processed to separate the roller to be processed from the main mold device.

[0153] The structural diagram of the roller to be processed obtained after the above step S1201 is completed can be referred to Figure 11-1 Since the roller threads 42 of the roller to be processed obtained after the operation of step S1201 are distributed over the entire outer surface of the roller body 41, the upper mold device 61 and the lower mold device 62 that are matched together can be rotated around the central axis of the roller to be processed to separate the roller to be processed from the upper mold device 61 and the lower mold device 62 that are matched together, so as not to damage the roller threads 42.

[0154] S1202, machining roller gears 43 on the roller threads 42 at both ends of the roller to be processed along its axis to obtain roller 4.

[0155] The structural diagram of the roller 4 obtained after the above step S1202 is completed can be referred to Figure 5 .

[0156] The roller 4 obtained by the above method is entirely made of plastic material, which not only reduces the manufacturing cost but also reduces the weight of the roller 4.

[0157] refer to Figure 13 The present application provides a method for manufacturing a roller, which is used to manufacture the roller 4 as described above, comprising the following steps:

[0158] S1301, install the upper mold device 61 and the lower mold device 62 on the injection molding machine.

[0159] S1302 , the upper mold device 61 and the lower mold device 62 are aligned, and the space between the aligned upper mold device 61 and the lower mold device 62 forms a seventh injection cavity for forming the roller 4 .

[0160] S1303 , injecting plastic into the seventh injection molding cavity to form a roller 4 .

[0161] It should be noted that the seventh injection cavity is adapted to the shape of the roller 4 , and the injection molding material is injected into the seventh injection cavity. After the injection molding material is solidified, the roller 4 can be directly formed, which greatly improves the manufacturing efficiency of the roller 4 .

[0162] S1304 , separating the upper mold device 61 and the lower mold device 62 after injection molding.

[0163] S1305. Remove the roller 4 from the lower mold device 62.

[0164] The above description is merely a specific embodiment of the present application, but the scope of protection of the present application is not limited thereto. Any changes or substitutions that can be easily conceived by a person skilled in the art within the technical scope disclosed in this application should be included in the scope of protection of this application. Therefore, the scope of protection of this application should be based on the scope of protection of the claims.

Claims

1. A roller, characterized in that: Applications for planetary roller screws include: Roller body (41); A roller thread (42) is provided on the outer side of the roller body (41); Two roller gears (43) are arranged on the outer side of the roller body (41), and the roller thread (42) is located between the two roller gears (43); The material of the roller is plastic.

2. The roller according to claim 1, characterized in that The tooth top circle diameter of the roller gear (43) is smaller than the minor diameter of the roller thread (42).

3. The roller according to claim 2, characterized in that The difference between the tooth top circle diameter of the roller gear (43) and the minor diameter of the roller thread (42) is greater than or equal to 0.1 mm.

4. The roller according to claim 1, characterized in that The tooth top circle diameter of the roller gear (43) is equal to the major diameter of the roller thread (42).

5. The roller according to any one of claims 1 to 4, characterized in that The roller body (41) is cylindrical.

6. The roller according to any one of claims 1 to 4, characterized in that The roller body (41), the roller thread (42) and the roller gear (43) are an integrated structure.

7. A planetary roller screw, characterized in that: include: A screw (1) having an external screw thread (11); a nut (2) surrounding and coaxial with the screw rod (1), the nut (2) having an internal nut thread (21); An inner gear ring (3) is disposed in the nut (2), and the inner gear ring (3) has an inner gear (31); A plurality of rollers (4) according to any one of claims 1 to 6, located between the screw (1) and the inner gear ring (3), the roller thread (42) meshing with the outer screw thread (11), the roller thread (42) meshing with the inner nut thread (21), and the roller gear (43) meshing with the inner gear (31); A roller retainer (5) is arranged inside the nut (2). A screw rod through hole (51) and a roller fixing hole (52) are provided on the roller retainer (5). The screw rod (1) is inserted into the screw rod through hole (51), and the end of the roller (4) is inserted into the roller fixing hole (52).

8. The planetary roller screw according to claim 7, characterized in that The material of the screw rod (1) is plastic; And / or, the nut (2) is made of plastic.

9. A method for manufacturing a roller, for manufacturing the roller according to claim 1, characterized in that: The following steps are involved: Mounting a main mold assembly on an injection molding machine, wherein a first injection molding cavity is formed in the main mold assembly for forming a portion of the roller body and the roller thread; Installing a first side mold assembly and a second side mold assembly on the injection molding machine and aligning them on both sides of the main mold assembly to form the remaining portion of the roller body and the two roller gears, the second injection molding cavity in the first side mold assembly, the third injection molding cavity in the second side mold assembly, and the first injection molding cavity being connected; Injecting plastic into the first injection molding cavity, the second injection molding cavity, and the third injection molding cavity to form the roller; The main mold assembly, the first side mold assembly and the second side mold assembly are removed, and the roller is taken out.

10. The manufacturing method according to claim 9, characterized in that: The main mold device includes an upper mold device and a lower mold device, and the main mold device is installed on the injection molding machine, including: Installing the upper mold device and the lower mold device on the injection molding machine and aligning them up and down to form the main mold device; The method of removing the main mold assembly, the first side mold assembly, and the second side mold assembly to remove the roller comprises the following steps: separating the first side mold assembly from the main mold assembly; separating the second side mold assembly from the main mold assembly; Separating the upper mold device from the lower mold device after injection molding; Remove the roller from the lower die assembly.

11. The manufacturing method according to claim 9, characterized in that: The method of removing the main mold assembly, the first side mold assembly, and the second side mold assembly to remove the roller comprises the following steps: Rotating the main mold assembly around the central axis of the roller to eject the second side mold assembly and separate the main mold assembly from the roller, wherein the tooth top circle diameter of the roller gear is smaller than the minor diameter of the roller thread; Remove the roller from the first side mold assembly.

12. A method for manufacturing a roller, for manufacturing the roller according to claim 1, characterized in that: The following steps are involved: Mounting a main mold device on an injection molding machine, wherein a fourth injection molding cavity is formed in the main mold device for forming the roller body and the roller thread; Injecting an injection molding material into the fourth injection molding cavity to form a roller to be processed, wherein the roller to be processed has a roller thread; The roller to be processed is taken out from the fourth injection molding cavity, and a roller gear is processed on the roller to be processed to obtain the roller.

13. The manufacturing method according to claim 12, characterized in that: The main mold device includes an upper mold device and a lower mold device, and the main mold device is installed on the injection molding machine, including: Installing the upper mold device and the lower mold device on the injection molding machine and aligning them up and down to form the main mold device; The process of removing the roller to be processed from the fourth injection molding cavity and processing a roller gear on the roller to be processed to obtain the roller comprises the following steps: Separating the upper mold device from the lower mold device after injection molding; Taking out the roller to be processed from the lower die device; Installing a first side mold assembly and a second side mold assembly on an injection molding machine, wherein the first side mold assembly and the second side mold assembly are used to form the roller gear; Inserting the roller to be processed into the first side mold device and the second side mold device along both ends of its axis, respectively, so that the space between the roller to be processed and the first side mold device forms a fifth injection cavity, and the space between the roller to be processed and the second side mold device forms a sixth injection cavity; Injecting plastic into the fifth injection molding cavity and the sixth injection molding cavity to form roller gears; The first side mold assembly and the second side mold assembly are removed to obtain the roller.

14. The manufacturing method according to claim 12, characterized in that: The main mold device includes an upper mold device and a lower mold device, and the main mold device is installed on the injection molding machine, including: Installing the upper mold device and the lower mold device on the injection molding machine and aligning them up and down to form the main mold device; The process of removing the roller to be processed from the fourth injection molding cavity and processing a roller gear on the roller to be processed to obtain the roller comprises the following steps: Separating the upper mold device from the lower mold device after injection molding; Taking out the roller to be processed from the lower die device; Roller gears are machined on roller threads at both ends of the roller to be machined along its axis to obtain the roller.

15. The manufacturing method according to claim 12, characterized in that: The process of removing the roller to be processed from the fourth injection molding cavity and processing a roller gear on the roller to be processed to obtain a roller comprises the following steps: Rotating the main mold device around the central axis of the roller to be processed to separate the roller to be processed from the main mold device; Roller gears are machined on roller threads at both ends of the roller to be machined along its axis to obtain the roller.

16. A method for manufacturing a roller, for manufacturing the roller according to claim 1, characterized in that: The following steps are involved: Installing the upper mold assembly and the lower mold assembly on the injection molding machine; The upper mold device and the lower mold device are aligned relative to each other, and the space between the aligned upper mold device and the lower mold device forms a seventh injection cavity for forming the roller; Injecting plastic into the seventh injection molding cavity to form the roller; Separating the upper mold device from the lower mold device after injection molding; Remove the roller from the lower die assembly.

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