Multi-bearing planetary roller screw mechanism

Abstract

The utility model discloses a multi-bearing planetary roller screw mechanism which comprises a motor, a rotating shaft, a bearing seat, a push rod, a planetary roller screw and a motor shell, the motor is fixedly installed in the motor shell, the bearing seat is connected with the motor shell, the motor is connected with the rotating shaft, the motor can drive the rotating shaft to rotate, the rotating shaft is inserted into the input end of the planetary roller screw, and the push rod is connected with the planetary roller screw. The output end of the planetary roller lead screw is connected with the push rod, the planetary roller lead screw is used for converting rotation of the rotating shaft into axial movement of the push rod, the planetary roller lead screw mechanism comprises a plurality of force bearing bearings, the outer ends of the force bearing bearings are fixedly installed on the bearing seat, and the inner ends of the force bearing bearings are fixedly installed on the rotating shaft. The inner end and the outer end of the force bearing are in axial fixation and circumferential rotation fit. The utility model has the technical advantages that the large bearing capacity can be borne, and the volume can be effectively controlled.

Description

Technical Field

[0001] The utility model relates to the technical field of precision adjustment equipment, in particular to a multi-bearing planetary roller screw mechanism. Background Art

[0002] Planetary roller screw (also known as planetary roller screw) is a mechanical transmission element used for high-precision motion control. It combines the high efficiency of ball screw and the high load-bearing capacity of gear transmission, and is commonly used in robots, electric motors, aerospace and high-end mechanical equipment.

[0003] With the development of society, the speed of large-load and miniaturization of electric cylinders, connecting rod mechanisms, thrusters and other equipment is accelerating, and the roller bearings used in the equipment have higher requirements in size and load capacity. Therefore, it is necessary to improve the existing planetary roller screw so that it can bear a larger load capacity while effectively controlling the volume. Utility Model Content

[0004] In view of the existing problems mentioned in the background technology, the utility model provides a multi-bearing planetary roller screw mechanism.

[0005] In order to achieve the above technical purpose, the technical solution adopted by the utility model is:

[0006] A multi-bearing planetary roller screw mechanism comprises a motor, a rotating shaft, a bearing seat, a push rod, a planetary roller screw and a motor housing, wherein the motor is fixedly installed in the motor housing, the bearing seat is connected to the motor housing, the motor is connected to the rotating shaft, the motor can drive the rotating shaft to rotate, the rotating shaft is inserted into the input end of the planetary roller screw, the output end of the planetary roller screw is connected to the push rod, the planetary roller screw is used to convert the rotation of the rotating shaft into axial movement of the push rod, the planetary roller screw mechanism comprises a plurality of load-bearing bearings, the outer end of the load-bearing bearing is fixedly installed on the bearing seat, the inner end is fixedly installed on the rotating shaft, the inner end and the outer end of the load-bearing bearing are axially fixed and circumferentially rotatable.

[0007] To optimize the technical solution, further improvements were made including:

[0008] The above-mentioned motor, bearing seat and planetary roller screw are distributed from left to right, the axial movement of the push rod is left and right, the left end of the bearing seat is fixedly connected to the motor housing, and the inner surface of the bearing seat is fixedly connected to the outer end of the load-bearing bearing.

[0009] A left groove is arranged on the left side of the inner surface of the bearing seat, and a right groove is arranged on the right side of the inner surface of the bearing seat. The load-bearing bearing includes an extending load-bearing bearing and a retracting load-bearing bearing. The extending load-bearing bearing is positioned and installed in the right groove of the bearing seat, and the left end of the extending load-bearing bearing is in conflict with the groove side wall of the right groove of the bearing seat. The retracting load-bearing bearing is positioned and installed in the left groove of the bearing seat, and the right end of the retracting load-bearing bearing is in conflict with the groove side wall of the left groove of the bearing seat.

[0010] The number of the above-mentioned extended bearing bearings is not less than two, the extended bearing bearings are arranged on the left and right, and the adjacent extended bearing bearings are in conflict with each other, and the number of the retracted bearing bearing is one.

[0011] The above-mentioned planetary roller screw includes a planetary roller fixed end and a plurality of planetary rollers. The planetary rollers are arranged in a ring in the circumferential direction to form a planetary roller group. The two ends of the planetary rollers can be rotatably positioned on the planetary roller fixed end. The rotating shaft penetrates into the center of the planetary roller group and engages with each planetary roller. The left end of the push rod is fixedly connected to a slide arranged on the outside of the planetary roller group, and the slide engages with each planetary roller.

[0012] A push rod housing is installed outside the above-mentioned push rod, the left end of the push rod housing is fixedly connected to the bearing seat, and a plug is provided in the gap between the right end of the push rod housing and the right end of the push rod. When the push rod moves left and right, the right end of the push rod can extend from the right end of the push rod housing.

[0013] The outer surface of the push rod housing is provided with two limit sensors, one on the left and one on the right, and the limit sensors are connected with the motor signal.

[0014] The extension bearing and retraction bearing are both angular contact ball bearings.

[0015] The push rod housing is provided with an openable and closable oil filling port, which connects the outer surface of the push rod housing and the inner surface of the push rod housing, and is used to inject lubricating oil into the push rod and the planetary roller screw.

[0016] The push rod housing is provided with an openable and closable breathing port, which connects the outer surface of the push rod housing and the inner surface of the push rod housing, and is used for gas circulation inside and outside the push rod housing.

[0017] Compared with the prior art, the utility model has the following beneficial effects:

[0018] The utility model has a load-bearing bearing installed on the bearing seat. When the push rod pushes the load, the reaction force generated by the load on the multi-bearing planetary roller screw mechanism is borne by the load-bearing bearing, which can significantly improve the load-bearing capacity of the multi-bearing planetary roller screw mechanism. At the same time, there are several load-bearing bearings. When the load-bearing capacity of a single load-bearing bearing is insufficient, multiple load-bearing bearings jointly bear the load. In this way, multiple smaller load-bearing bearings can be used to replace a larger single bearing, thereby reducing the diameter of the entire planetary roller screw mechanism. The utility model is more suitable for use in robots, motors and other equipment with high space requirements.

[0019] The utility model further improves the bearing seat, and the inner surface of the bearing seat is provided with left and right grooves, and the extending bearing bearing and the retracting bearing bearing are allocated in the left and right grooves. Since the thrust is a large load, the number of the extending bearing bearing is large, and more than two are required, while when it is pulled back, it is unloaded, so only one retracting bearing bearing is sufficient. The utility model saves the installation space of the bearing bearing by reasonably allocating the number of the extending bearing bearing and the retracting bearing bearing, and realizes the full utilization of the bearing bearing capacity. BRIEF DESCRIPTION OF THE DRAWINGS

[0020] Figure 1 It is a schematic diagram of the utility model;

[0021] Figure 2 for Figure 1 AA section view;

[0022] Figure 3 It is a three-dimensional diagram of the utility model;

[0023] Figure 4 It is a structural exploded view of the utility model.

[0024] Names marked in the figure: motor 1, rotating shaft 2, bearing seat 3, push rod 4, push rod housing 41, plug 42, limit sensor 43, refueling port 44, breathing port 45, planetary roller screw 5, planetary roller 51, planetary roller fixed end 52, motor housing 6, load-bearing bearing 7, extended load-bearing bearing 71, retracted load-bearing bearing 72. DETAILED DESCRIPTION

[0025] In order to make the purpose, technical solutions and advantages of the present application clearer, the present application is described and illustrated below in conjunction with the accompanying drawings and embodiments. It should be understood that the specific embodiments described herein are only used to explain the present application and are not intended to limit the present application. Based on the embodiments provided in the present application, all other embodiments obtained by ordinary technicians in the field without making creative work are within the scope of protection of the present application.

[0026] Obviously, the drawings described below are only some examples or embodiments of the present application. For ordinary technicians in this field, the present application can also be applied to other similar scenarios based on these drawings without creative work. In addition, it can also be understood that although the efforts made in this development process may be complicated and lengthy, for ordinary technicians in this field related to the content disclosed in this application, some changes in design, manufacturing or production based on the technical content disclosed in this application are just conventional technical means, and should not be understood as insufficient content disclosed in this application.

[0027] Reference to "embodiments" in this application means that a particular feature, structure, or characteristic described in conjunction with the embodiments may be included in at least one embodiment of the present application. The appearance of the phrase in various locations in the specification does not necessarily refer to the same embodiment, nor is it an independent or alternative embodiment that is mutually exclusive with other embodiments. It is explicitly and implicitly understood by those of ordinary skill in the art that the embodiments described in this application may be combined with other embodiments without conflict.

[0028] Unless otherwise defined, the technical terms or scientific terms involved in this application should be understood by people with ordinary skills in the technical field to which this application belongs. The words "one", "a", "a", "the" and the like involved in this application do not indicate a quantitative limitation and may indicate the singular or plural. The terms "include", "comprise", "have" and any of their variations involved in this application are intended to cover non-exclusive inclusions; for example, a process, method, system, product or device that includes a series of steps or units (units) is not limited to the listed steps or units, but may also include unlisted steps or units, or may also include other steps or units inherent to these processes, methods, products or devices. The words "connect", "connected", "coupled" and the like involved in this application are not limited to physical or mechanical connections, but may include electrical connections, whether direct or indirect. The "multiple" / "several" involved in this application refers to two or more. "And / or" describes the association relationship of associated objects, indicating that there may be three relationships, for example, "A and / or B" can mean: A exists alone, A and B exist at the same time, and B exists alone. The character " / " generally indicates that the objects before and after are in an "or" relationship. The terms "first", "second", "third", etc. involved in this application are only used to distinguish similar objects and do not represent a specific ordering of the objects.

[0029] like Figure 1-4 As shown, the multi-bearing planetary roller screw mechanism of the utility model mainly includes a motor 1, a rotating shaft 2, a bearing seat 3, a push rod 4, a planetary roller screw 5, a motor housing 6, and a load-bearing bearing 7.

[0030] The motor 1 is installed in the motor housing 6 , and the output end of the motor 1 is located at the right end, and the output end of the motor 1 is connected to the rotating shaft 2 .

[0031] The surface of the rotating shaft 2 is provided with a thread, and the right part of the rotating shaft 2 is provided with a thread for matching with the planetary roller 51, and the thread helix angle is not zero. The right end of the rotating shaft 2 extends to the center of the planetary roller 51 arranged in a ring in the circumferential direction to form a planetary roller group.

[0032] The left end of the bearing seat 3 is fixedly connected to the motor housing 6. The bearing seat 3 is used to install the load-bearing bearing 7. Figure 2 It can be seen that the middle part of the inner surface of the bearing seat 3 protrudes toward the axial direction, so that grooves are formed at the left and right ends of the inner surface of the bearing seat 3. A retractable bearing 72 is installed in the left groove, and three extended bearing bearings 71 are installed in the right groove.

[0033] The reason why three extension bearing bearings 71 and one retraction bearing bearing 72 are used in pairs is that the multi-bearing planetary roller screw mechanism has only thrust as a large load-bearing force, so three extension bearing bearings 71 are needed. When pulling back, it is unloaded and only has its own weight, so only one retraction bearing bearing 72 is needed.

[0034] For example, a single angular contact ball bearing with an outer diameter of 140mm can only carry 15 tons. If you want to carry a load of 30 tons, you need to use an angular contact ball bearing with an outer diameter of more than 200mm. For some robots and motors with high space requirements, the volume is too large. Using three angular contact ball bearings with an outer diameter of 140mm in series can achieve a load of 30-35 tons, which does not increase the diameter of the planetary roller screw mechanism and can effectively improve the load-bearing capacity of the planetary roller screw mechanism.

[0035] The planetary roller screw 5 is a common device on the market. It combines the characteristics of planetary rollers and screws. It is used in high-precision and high-load applications. It has high transmission efficiency, small size and weight, and excellent load capacity. The planetary roller screw 5 is used to convert the rotation of the shaft 2 into the axial movement of the push rod 4. The direction of the axial movement of the push rod 4 is achieved by the forward and reverse rotation of the motor 1.

[0036] The push rod housing 41 is installed on the outside of the push rod 4, and the push rod housing 41 is fixedly connected to the bearing seat 3. There are two limit sensors 43 on the push rod housing 41. The limit sensors 43 are used to detect whether the push rod 4 is extended and retracted into place, and then provide information for the motor 1 to stop or change.

[0037] The push rod housing 41 is provided with a refueling port 44 and a breathing port 45. The refueling port 44 is used for regularly adding or replacing lubricating oil, and the breathing port 45 is used for balancing the air pressure difference generated inside and outside the housing due to heat.

[0038] The above are only preferred implementations of the utility model. The protection scope of the utility model is not limited to the above embodiments. All technical solutions under the idea of ​​the utility model belong to the protection scope of the utility model. It should be pointed out that for ordinary technicians in this technical field, some improvements and modifications without departing from the principle of the utility model should be regarded as the protection scope of the utility model.

Claims

1. A multi-bearing planetary roller screw mechanism, comprising a motor (1), a rotating shaft (2), a bearing seat (3), a push rod (4), a planetary roller screw (5) and a motor housing (6), wherein the motor (1) is fixedly mounted in the motor housing (6), the bearing seat (3) is connected to the motor housing (6), the motor (1) is connected to the rotating shaft (2), the motor (1) can drive the rotating shaft (2) to rotate, the rotating shaft (2) is inserted into the input end of the planetary roller screw (5), the output end of the planetary roller screw (5) is connected to the push rod (4), and the planetary roller screw (5) is used to convert the rotation of the rotating shaft (2) into the axial movement of the push rod (4), and is characterized in that: The planetary roller screw mechanism comprises a plurality of load-bearing bearings (7), wherein the outer ends of the load-bearing bearings (7) are fixedly mounted on the bearing seat (3), and the inner ends are fixedly mounted on the rotating shaft (2), and the inner and outer ends of the load-bearing bearings (7) are axially fixed and circumferentially rotatably matched.

2. A multi-bearing planetary roller screw mechanism according to claim 1, characterized in that: The motor (1), the bearing seat (3) and the planetary roller screw (5) are distributed from left to right, the axial movement of the push rod (4) is left-right movement, the left end of the bearing seat (3) is fixedly connected to the motor housing (6), and the inner surface of the bearing seat (3) is fixedly connected to the outer end of the load-bearing bearing (7).

3. A multi-bearing planetary roller screw mechanism according to claim 2, characterized in that: The left side of the inner surface of the bearing seat (3) is provided with a left groove, and the right side of the inner surface of the bearing seat (3) is provided with a right groove. The load-bearing bearing (7) includes an extending load-bearing bearing (71) and a retracting load-bearing bearing (72). The extending load-bearing bearing (71) is positioned and installed in the right groove of the bearing seat (3), and the left end of the extending load-bearing bearing (71) is in abutment with the groove side wall of the right groove of the bearing seat (3). The retracting load-bearing bearing (72) is positioned and installed in the left groove of the bearing seat (3), and the right end of the retracting load-bearing bearing (72) is in abutment with the groove side wall of the left groove of the bearing seat (3).

4. A multi-bearing planetary roller screw mechanism according to claim 3, characterized in that: The number of the extending bearing bearings (71) is not less than two, the extending bearing bearings (71) are arranged left and right, and adjacent extending bearing bearings (71) are in conflict with each other, and the number of the retracting bearing bearing (72) is one.

5. A multi-bearing planetary roller screw mechanism according to claim 4, characterized in that: The planetary roller screw (5) comprises a planetary roller fixed end (52) and a plurality of planetary rollers (51), wherein the planetary rollers (51) are arranged in a ring in the circumferential direction to form a planetary roller group, and both ends of the planetary rollers (51) can be rotatably positioned on the planetary roller fixed end (52), the rotating shaft (2) penetrates the center of the planetary roller group and engages with each planetary roller (51), and the left end of the push rod (4) is fixedly connected to a slide arranged on the outside of the planetary roller group, and the slide engages with each planetary roller (51).

6. A multi-bearing planetary roller screw mechanism according to claim 5, characterized in that: A push rod housing (41) is installed on the outside of the push rod (4), the left end of the push rod housing (41) is fixedly connected to the bearing seat (3), and a plug (42) is provided in the gap between the right end of the push rod housing (41) and the right end of the push rod (4). When the push rod (4) moves left and right, the right end of the push rod (4) can extend from the right end of the push rod housing (41).

7. A multi-bearing planetary roller screw mechanism according to claim 6, characterized in that: The outer surface of the push rod housing (41) is provided with two limit sensors (43), one on the left and one on the right. The limit sensors (43) are connected to the motor (1) for signal transmission.

8. The multi-bearing planetary roller screw mechanism according to claim 7, characterized in that: The extension bearing bearing (71) and the retraction bearing bearing (72) are both angular contact ball bearings.

9. The multi-bearing planetary roller screw mechanism according to claim 7, characterized in that: The push rod housing (41) is provided with an openable and closable oil filling port (44), the oil filling port (44) connects the outer surface of the push rod housing (41) and the inner surface of the push rod housing (41), and the oil filling port (44) is used to inject lubricating oil into the push rod (4) and the planetary roller screw (5).

10. A multi-bearing planetary roller screw mechanism according to claim 9, characterized in that: The push rod housing (41) is provided with an openable and closable breathing port (45), the breathing port (45) connecting the outer surface of the push rod housing (41) and the inner surface of the push rod housing (41), and the breathing port (45) is used for gas circulation inside and outside the push rod housing (41).

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