Mechanical joint, mechanical arm, and cleaning device
By designing the mounting base, drive unit, lead screw, nut, and rolling assembly, the problems of complex joint structure and large size of the robotic arm were solved, achieving a compact design and reliable motion, and improving service life and stability.
Patent Information
- Authority / Receiving Office
- WO · WO
- Patent Type
- Applications
- Current Assignee / Owner
- BEIJING ROCKROBO TECH CO LTD
- Filing Date
- 2025-12-09
- Publication Date
- 2026-07-09
AI Technical Summary
Existing robotic arms have complex joint structures and large volumes, making it difficult to meet the requirements of compact design. They are also prone to jamming during lifting and lowering, affecting their service life and reliability.
The design employs a mounting base, drive unit, lead screw, nut, and rolling assembly. The lifting or lowering of the articulated arm is achieved through rolling and threaded connections. The axial limiting is achieved using the rolling assembly, which includes rolling modules and retaining rings, simplifying the bearing structure and reducing the axial height.
This results in a compact and small robotic arm structure, improved service life and reliability, reduced damage to the drive unit, and ensured stable and smooth movement.
Smart Images
Figure CN2025141107_09072026_PF_FP_ABST
Abstract
Description
Mechanical joints, robotic arms, and cleaning equipment Cross-references to related applications
[0001] This application claims priority to China National Intellectual Property Administration (CNIPA) application No. 202423322102.3, entitled "Mechanical Joint, Robotic Arm and Cleaning Equipment", filed on December 31, 2024, the entire contents of which are incorporated herein by reference. Technical Field
[0002] This disclosure relates to the field of robotic arm technology, and more particularly to a mechanical joint, a robotic arm, and a cleaning device. Background Technology
[0003] With the continuous development of science and technology and the continuous improvement of people's living standards, self-moving cleaning equipment, such as intelligent sweeping robots, has been increasingly entering our daily lives. Summary of the Invention
[0004] The disclosure section introduces a series of simplified concepts, which will be further explained in detail in the detailed description section. This part of the disclosure is not intended to limit the key features and essential technical features of the claimed technical solution, nor is it intended to determine the scope of protection of the claimed technical solution.
[0005] This disclosure provides a mechanical joint for a robotic arm. The mechanical joint includes: a mounting base, a drive unit, a lead screw, a nut, and a rolling assembly. The mounting base is hinged to the joint arm of the robotic arm and connected to the drive unit. The lead screw is tactilely connected to the mounting base via the rolling assembly. The first end of the lead screw is located inside the mounting base and is poweredly connected to the drive unit. The second end of the lead screw passes through the nut and is threadedly connected to the nut. The nut is hinged to the base of the robotic arm. The drive unit drives the lead screw to rotate relative to the mounting base, so that the lead screw and the nut move relative to each other to raise or lower the joint arm relative to the base.
[0006] Furthermore, the lead screw is provided with a connecting boss located inside the mounting base, and the rolling assembly includes two rolling modules, which are respectively arranged on the two platforms of the connecting boss; the interior of the mounting base includes two walls corresponding to the two platforms, and the two platforms are respectively rolledly connected to the corresponding walls through the rolling modules.
[0007] Furthermore, the rolling module includes: a retainer, a rolling element, and a gasket. The retainer is used to support the rolling element and mount it on the table surface. The rolling element contacts the table surface. The gasket is located between the retainer and the wall surface.
[0008] Furthermore, a receiving groove for accommodating the rolling element is provided on the table surface.
[0009] Furthermore, the rolling assembly also includes a retaining ring, which is inserted between adjacent walls and a washer to limit the axial movement of the lead screw relative to the mounting base.
[0010] Furthermore, the two walls are a first wall and a second wall, with the first wall close to the drive unit and the retaining ring located between the second wall and the adjacent gasket.
[0011] Furthermore, the first wall surface is provided with mounting holes and clearance holes, and the mechanical joint also includes fasteners. The fasteners pass through the mounting holes and are connected to the housing of the drive unit. The clearance holes are used to avoid the output shaft of the drive unit. At least a portion of the gasket adjacent to the first wall surface is in contact with the fasteners.
[0012] Furthermore, the connecting boss and the first end of the lead screw are arranged at intervals, and the end face of the first end is provided with a connecting hole that matches the output shaft of the drive unit. The connecting hole and the connecting boss are arranged coaxially.
[0013] Furthermore, the outer wall of the mounting base is provided with a first cylindrical boss, and the mounting base is hinged to the articulated arm through the first cylindrical boss.
[0014] Furthermore, a second cylindrical boss is provided on the outer wall of the nut, and the nut is hinged to the base through the second cylindrical boss.
[0015] Furthermore, the mechanical joint also includes: a connecting shaft, the axis of which is parallel to the axis of the second cylindrical boss and connected to the base; the end of the joint arm near the base is sleeved on the outside of the connecting shaft and rotatably connected to the connecting shaft.
[0016] An embodiment of the second aspect of this disclosure provides a robotic arm, including: a mechanical joint of any one of the first aspects.
[0017] An embodiment of a third aspect of this disclosure provides a cleaning device, including: a robotic arm as described in the second aspect.
[0018] The above description is merely an overview of the technical solution disclosed herein. In order to better understand the technical means of this disclosure and to implement it in accordance with the contents of the specification, and to make the above and other objects, features and advantages of this disclosure more apparent and understandable, specific embodiments of this disclosure are described below. Attached Figure Description
[0019] Various other advantages and benefits will become apparent to those skilled in the art upon reading the following detailed description of preferred embodiments. The accompanying drawings are for illustrative purposes only and are not intended to limit the scope of this disclosure. Furthermore, the same reference numerals denote the same parts throughout the drawings. Wherein:
[0020] Figure 1 shows one of the partial structural schematic diagrams of the robotic arm provided in the embodiments of this disclosure;
[0021] Figure 2 shows a second partial structural schematic diagram of the robotic arm provided in an embodiment of this disclosure;
[0022] Figure 3 shows a partial structural schematic diagram of the mechanical joint provided in an embodiment of this disclosure;
[0023] Figure 4 shows a partially enlarged schematic diagram of point A in the embodiment shown in Figure 3;
[0024] Figure 5 shows a schematic diagram of the structure of the connector provided in an embodiment of this disclosure;
[0025] Figure 6 shows a schematic diagram of the lead screw provided in an embodiment of this disclosure;
[0026] Figure 7 shows a schematic diagram of the structure of the nut provided in an embodiment of this disclosure.
[0027] Explanation of reference numerals in the attached drawings: 100 Mechanical joint, 110 Mounting base, 111 Wall surface, 112 First wall surface, 113 Second wall surface, 114 First cylindrical boss, 115 Mounting hole, 116 Clearance hole, 120 Drive unit, 130 Lead screw, 131 Connecting boss, 132 Platform, 133 First platform, 134 Second platform, 135 Receiving groove, 136 Connecting hole, 137 First end, 138 Second end, 140 Nut, 141 Second cylindrical boss, 1 50 Rolling assembly, 151 Rolling module, 1511 First rolling module, 1512 Second rolling module, 1513 Retainer, 1513a First retainer, 1513b Second retainer, 1514 Washer, 1514a First washer, 1514b Second washer, 1515 Rolling element, 152 Snap ring, 160 Fastener, 170 Connecting shaft, 200 Robotic arm, 210 Base, 220 Articulated arm, 230 Rotary joint, 240 Base. Detailed Implementation
[0028] The following description provides numerous specific details to offer a more thorough understanding of the technical solutions provided in this disclosure. However, it will be apparent to those skilled in the art that the technical solutions provided in this disclosure can be implemented without one or more of these details.
[0029] It should be noted that the terminology used herein is for the purpose of describing particular embodiments only and is not intended to limit the exemplary embodiments according to this disclosure. As used herein, the singular form is intended to include the plural form as well, unless the context clearly indicates otherwise. Furthermore, it should be understood that when the terms “comprising” and / or “including” are used in this specification, they indicate the presence of the stated features, integrals, steps, operations, elements, and / or components, but do not exclude the presence or addition of one or more other features, integrals, steps, operations, elements, components, and / or combinations thereof.
[0030] Exemplary embodiments according to this disclosure will now be described in more detail with reference to the accompanying drawings. However, these exemplary embodiments may be implemented in many different forms and should not be construed as being limited to the embodiments set forth herein. It should be understood that these embodiments are provided so that this disclosure will be thorough and complete, and that the concept of these exemplary embodiments will be fully conveyed to those skilled in the art.
[0031] As shown in Figures 1 to 7, an embodiment of the first aspect of this disclosure provides a mechanical joint 100, an embodiment of the second aspect of this disclosure provides a robotic arm 200, and an embodiment of the third aspect of this disclosure provides a cleaning device. The mechanical joint 100 is applied to the robotic arm 200, and the robotic arm 200 is applied to the cleaning device, which can be a sweeping robot, a sweeping and mopping robot, or other cleaning robots that meet the requirements.
[0032] The cleaning equipment includes, but is not limited to, a main body, a drive system, and a cleaning system. These systems coordinate with each other to enable the cleaning equipment to move autonomously and perform its cleaning function. The functional components constituting these systems are integrated within the main body. It is understood that the cleaning equipment can be a self-moving cleaning device. A self-moving cleaning device is a device that automatically performs cleaning operations in a designated area without user intervention.
[0033] Furthermore, the robotic arm 200 is applied to cleaning equipment, such as when the robotic arm 200 is connected to the main body of the cleaning equipment, so that the robotic hand at the end of the robotic arm 200 can grasp or move obstacles, objects, and garbage near the cleaning equipment, so as to better realize the autonomous cleaning function.
[0034] When the robotic arm 200 is in working condition, some of the mechanical joints 100 need to be kept in an elevated state so that the robotic hand at the end of the robotic arm 200 can reach a suitable position to perform grasping or placing operations. When the robotic arm 200 is not in working condition, the elevated mechanical joints 100 need to be lowered so that the robotic arm 200 is in a folded and stowed state for storage.
[0035] As shown in Figures 1, 2, and 3, an embodiment of the first aspect of this disclosure provides a mechanical joint 100 for connecting a base 210 and a joint arm 220 of a robotic arm 200. The mechanical joint 100 includes a mounting base 110, a drive unit 120, a lead screw 130, a nut 140, and a rolling assembly 150. The mounting base 110 is hinged to the joint arm 220 and connected to the drive unit 120. The lead screw 130 is tactilely connected to the mounting base 110 via the rolling assembly 150. The first end 137 of the lead screw 130 is located inside the mounting base 110 and is poweredly connected to the drive unit 120. The second end 138 of the lead screw 130 passes through the nut 140 and is threadedly connected to the nut 140. The nut 140 is hinged to the base 210. The drive unit 120 drives the lead screw 130 to rotate relative to the mounting base 110, so that the lead screw 130 and the nut 140 move relative to each other to lift or lower the joint arm 220 relative to the base 210.
[0036] The base 210 of the robotic arm 200 can be a structure for connecting the robotic arm 200 to the main body of the cleaning equipment, or it can be a part of other joints of the robotic arm 200. The articulated arm 220 of the robotic arm 200 can be connected to the base 210 through the mechanical joint 100, so that the articulated arm 220 can be raised or lowered relative to the base 210.
[0037] The mechanical joint 100 provided in this embodiment includes a mounting base 110, a drive unit 120, a lead screw 130, a nut 140, and a rolling assembly 150. The drive unit 120 is connected to the mounting base 110, and the mounting base 110 is hinged to the joint arm 220, allowing the mounting base 110 and the drive unit 120 connected to the mounting base 110 to rotate relative to the joint arm 220. The nut 140 is hinged to the base 210, allowing the nut 140 to rotate relative to the base 210. The first end 137 of the lead screw 130 is located inside the mounting base 110 and is poweredly connected to the drive unit 120. The second end 138 of the lead screw 130 passes through the nut 140 and is threadedly connected to the nut 140. The lead screw 130 is connected to the rotating seat via the rolling assembly 150. Thus, the drive unit 120 drives the lead screw 130 to rotate, allowing the nut 140 and the lead screw 130 to move relative to each other. Since the nut 140 is hinged to the base 210, and the drive unit 120 is hinged to the articulated arm 220 via the mounting base 110, the lead screw 130 can move relative to the nut 140 towards or away from the base 210. This allows the articulated arm 220 to be raised or lowered relative to the base 210, so as to meet the needs of the robotic arm 200 to be raised to different heights and positions to meet the needs of clamping operations when it is working, and to meet the needs of the robotic arm 200 to be lowered to a folded state for storage when it is not working.
[0038] Since the lead screw 130 is rolledly connected to the mounting base 110 through the rolling assembly 150, which may include balls or needle rollers, the lead screw 130 can simultaneously withstand large axial thrust and axial tension, as well as a certain radial load. In other words, the lead screw 130 can simultaneously bear large axial loads and radial loads, reducing damage to the drive unit 120, improving the stability and reliability of the operation of the drive unit 120 and the lead screw 130, and helping to improve the service life and reliability of the mechanical joint 100.
[0039] Understandably, when the mechanical joint 100 drives the articulated arm 220 to rise relative to the base 210 to an unfolded state, the articulated arm 220 can be raised and unfolded relative to the base 210 to a vertical or approximately vertical position, at which point the robotic arm 200 can be in an unfolded working state. When the mechanical joint 100 drives the articulated arm 220 to fall relative to the base 210 to a folded state, the articulated arm 220 can be in a horizontal or approximately horizontal position, and the robotic arm 200 can be in a folded and stored position without working, thereby reducing the space occupied by the robotic arm 200. The raising or lowering operation of the articulated arm 220 relative to the base 210 can be achieved through the cooperation of the connecting seat, drive unit 120, rolling assembly 150, lead screw 130, and nut 140. The structure is simple, the operation is convenient, and it can meet the design requirements of a compact structure and small size for the robotic arm 200.
[0040] Furthermore, the articulated arm 220 is hinged to the base 210, and the nut 140 is hinged to the base 210, so that during the process of the drive unit 120 driving the lead screw 130 and the nut 140 to move relative to each other to drive the articulated arm 220 to rise or fall relative to the base 210, the nut 140 and the base 210 will not interfere or get stuck, that is, the nut 140 can rotate relative to the base 210, so as to ensure that the lead screw 130 and the nut 140 move within a certain range and are adapted to the rotation range of the articulated arm 220 relative to the base 210.
[0041] Furthermore, the drive unit 120 includes a housing and an output shaft. The housing of the drive unit 120 is connected to the mounting base 110, and the output shaft of the drive unit 120 is poweredly connected to the first end 137 of the lead screw 130, so that the rotation of the output shaft of the drive unit 120 can drive the lead screw 130 to rotate. Specifically, the housing of the drive unit 120 can be connected to the mounting base 110 by means of bolt structure, snap-fit structure, plug-in structure, tenon structure, magnetic structure, welding, bonding, etc.
[0042] The articulated arm 220 and the base 210 are hinged, so that the mechanical joint 100 can drive the articulated arm 220 to be raised or lowered relative to the base 210.
[0043] As shown in Figures 3, 4 and 5, in some possible embodiments provided in this disclosure, the lead screw 130 is provided with a connecting boss 131 located inside the mounting base 110, and the rolling assembly 150 includes two rolling modules 151, which are respectively arranged on the two platforms 132 of the connecting boss 131; the interior of the mounting base 110 includes two walls 111 corresponding to the two platforms 132, and the two platforms 132 are respectively rolledly connected to the corresponding walls 111 through the rolling modules 151.
[0044] In this embodiment, by distributing two rolling modules 151 on both sides of the connecting boss 131 of the lead screw 130, the two rolling modules 151 respectively achieve rolling connection between the platform 132 on both sides of the connecting boss 131 and the wall surface 111 of the mounting base 110. This allows the two rolling modules 151 and the connecting boss 131 to cooperate to form a bearing device. Thus, the drive unit 120 operates to rotate the lead screw 130. Since the two platform surfaces 132 of the connecting boss 131 of the lead screw 130 are rollingly connected to the two wall surfaces 111 inside the mounting base 110 through the rolling modules 151, the lead screw 130 can rotate relative to the mounting base 110. Simultaneously, this arrangement makes the connecting boss 131 of the lead screw 130 a part of the bearing device structure, which simplifies the structure of the bearing device and achieves the design requirements of a compact structure and small size for the lead screw 130, rolling assembly 150, and mounting base 110, thus reducing the overall volume of the mechanical joint 100.
[0045] Meanwhile, the rolling assembly 150 is located inside the mounting base 110, which provides good protection for the rolling assembly 150, thus improving the service life of the rolling assembly 150 and consequently the service life of the mechanical shut-off mechanism.
[0046] Specifically, the two rolling modules 151 may include balls or needle rollers. The two rolling modules 151 can cooperate to form a bearing device. Specifically, the needle rollers or balls in the two rolling modules 151 can cooperate to form a thrust bearing.
[0047] Specifically, as shown in Figure 3, the rolling module 151 includes a first rolling module 1511 and a second rolling module 1512. As shown in Figure 4, the wall surface 111 within the mounting base 110 may include a first wall surface 112 and a second wall surface 113, wherein the first wall surface 112 is disposed near the drive unit 120. As shown in Figure 5, the connecting boss 131 of the lead screw 130 may include a first platform 133 and a second platform 134. The first platform 133 is opposite to the first wall surface 112, and the second platform 134 is opposite to the second wall surface 113. The first rolling module 1511 is located between the first platform 133 and the first wall surface 112, and the second rolling module 1512 is located between the second platform 134 and the second wall surface 113.
[0048] As shown in Figure 4, in some possible embodiments provided in this disclosure, the rolling module 151 includes: a retainer 1513, a rolling element 1515, and a gasket 1514. The retainer 1513 is used to support the rolling element 1515 and is mounted on the table 132. The rolling element 1515 is in contact with the table 132. The gasket 1514 is located between the retainer 1513 and the wall 111.
[0049] Since traditional bearings include a retainer to carry the balls and upper and lower gaskets, in the mechanical joint 100 provided in this embodiment, the retainer 1513 of the rolling assembly 150 is directly mounted on the platform 132, and the rolling element 1515 is in direct contact with the platform 132. This simplifies the setting of the gasket 1514 between the rolling assembly 150 and the platform 132 connecting the boss 131, thereby reducing the axial height of the mechanical joint 100 and meeting the design requirements of the mechanical joint 100 to be compact and small in size, which in turn meets the design requirements of the robotic arm 200 to be compact and small in size.
[0050] Meanwhile, in this embodiment, the rolling elements 1515 of the two rolling modules 151 contact the two platforms 132 of the connecting boss 131 respectively. This simplifies the setting of the two shims 1514, further reduces the axial height of the mechanical joint 100, and meets the design requirements of the mechanical joint 100 to be compact and small in size.
[0051] As shown in Figure 5, in some possible embodiments provided in this disclosure, a receiving groove 135 for accommodating the rolling element 1515 is provided on the platform 132. The provision of the receiving groove 135 restricts the movement of the rolling element 1515 relative to the platform 132, which helps to improve the stability and reliability of the relative rotation of the connecting boss 131 and the mounting base 110, thereby improving the stability and reliability of the relative rotation of the lead screw 130 and the mounting base 110.
[0052] Specifically, the receiving groove 135 can be an annular groove. The rolling element 1515 can be a plurality of balls or needle rollers arranged in a ring, and the plurality of balls or needle rollers can be accommodated in the annular groove.
[0053] Specifically, the receiving grooves 135 can be respectively provided on the first platform 133 and the second platform 134 to accommodate the rolling element 1515 of the first rolling module 1511 and the rolling element 1515 of the second rolling module 1512.
[0054] As shown in Figures 3 and 4, in some possible embodiments provided in this disclosure, the rolling assembly 150 further includes a retaining ring 152, which is inserted between adjacent wall surfaces 111 and gaskets 1514 to limit the axial movement of the lead screw 130 relative to the mounting base 110.
[0055] In this embodiment, by inserting a retaining ring 152 between adjacent wall surfaces 111 and gaskets 1514, the wall surfaces 111 and adjacent platform surfaces 132 are clamped together, thereby axially limiting the rolling module 151 and preventing the lead screw 130 from moving axially. This effectively limits the axial movement of the lead screw 130 relative to the mounting base 110, reducing or avoiding axial runout of the lead screw 130 relative to the mounting base 110. This improves the motion accuracy and stability of the mechanical joint 100, enabling the joint arm 220 to be reliably and stably raised and lowered relative to the base 210, reducing the possibility of swaying during the movement of the joint arm 220.
[0056] As shown in Figures 3 and 4, in some possible embodiments provided in this disclosure, the two walls 111 are a first wall 112 and a second wall 113, respectively. The first wall 112 is close to the drive part 120, and the retaining ring 152 is located between the second wall 113 and the adjacent gasket 1514.
[0057] Since the mounting base 110 usually needs to be connected to the housing of the drive unit 120 by means of the first wall 112, and the housing of the drive unit 120 and the mounting base 110 are usually connected before the lead screw 130 and the rolling assembly 150 are installed, the snap ring 152 is arranged between the second wall 113 and the adjacent washer 1514 to facilitate the assembly of the lead screw 130 and the rolling assembly 150 and to facilitate the operation of the snap ring 152 by the operator.
[0058] As shown in Figures 3 and 6, in some possible embodiments provided in this disclosure, the first wall surface 112 of the mounting base 110 is provided with a mounting hole 115 and a clearance hole 116. The mechanical joint 100 also includes a fastener 160, which passes through the mounting hole 115 and connects to the housing of the drive unit 120, thereby ensuring a reliable connection between the housing of the drive unit 120 and the mounting base 110. The fastener 160 can be a bolt, which secures the mounting base 110 and the housing of the drive unit 120, facilitating easy assembly and disassembly.
[0059] Furthermore, the output shaft of the drive unit 120 is allowed to pass through the clearance hole 116 on the first wall surface 112, so that the output shaft of the drive unit 120 can be poweredly connected to the first end 137 of the lead screw 130 located inside the mounting base 110, so that the rotation of the output shaft can drive the lead screw 130 to rotate.
[0060] At least a portion of the gasket 1514 adjacent to the first wall surface 112 contacts the fastener 160. Thus, through the contact between the gasket 1514 and the fastener 160 fixed on the first wall surface 112, indirect contact between the gasket 1514 and the first wall surface 112 is achieved. This helps to save internal space of the mounting base 110, thereby reducing the volume of the mounting base 110 and meeting the design requirements of compact layout and small size of the mechanical joint 100.
[0061] Specifically, there are at least two fasteners 160, which are distributed around the periphery of the output shaft. These two fasteners 160 connect the mounting base 110 and the housing of the drive unit 120, thereby improving the reliability and stability of the connection between the mounting base 110 and the housing of the drive unit 120. Specifically, as shown in FIG4, the gasket 1514 adjacent to the first wall surface 112 can be a first gasket 1514a, and the side of the first gasket 1514a away from the first platform can contact the two fasteners 160.
[0062] As shown in Figure 5, in some possible embodiments provided in this disclosure, the connecting boss 131 and the first end 137 of the lead screw 130 are arranged at intervals, thus providing installation space for the first rolling assembly 150, so that the two rolling assemblies 150 can be distributed on both sides of the connecting boss 131.
[0063] The lead screw 130 has a connecting hole 136 on its end face at the first end 137. The connecting hole 136 matches the output shaft of the drive unit 120. Thus, the drive unit 120 and the lead screw 130 are connected by the connecting hole 136 and the output shaft.
[0064] Specifically, the inner wall of the connecting hole 136 may be provided with a first limiting surface, and the output shaft may be provided with a second limiting surface. The first limiting surface and the second limiting surface cooperate to limit the circumferential rotation of the lead screw 130 relative to the output shaft, so that the rotation of the output shaft can drive the lead screw 130 to rotate. Specifically, the connecting hole 136 may be a D-shaped hole or a flat hole, and the output shaft may be a D-shaped shaft or a flat shaft.
[0065] Furthermore, the connecting hole 136 and the connecting boss 131 are arranged coaxially, thereby improving the coaxiality of the output shaft of the drive unit 120 and the lead screw 130, thus improving the transmission accuracy and, consequently, the motion accuracy and motion stability of the mechanical shut-off mechanism.
[0066] As shown in Figures 2 and 6, in some possible embodiments provided in this disclosure, the outer wall of the mounting base 110 is provided with a first cylindrical boss 114, and the mounting base 110 is hinged to the articulated arm 220 through the first cylindrical boss 114.
[0067] The first cylindrical boss 114 can be located on opposite sides of the mounting base 110. A first groove is formed on the inner wall of the articulated arm 220, and the first cylindrical boss 114 is accommodated within and can rotate within this groove. This allows for a hinged connection between the mounting base 110 and the articulated arm 220. The structure is simple, easy to manufacture, and low in cost, making it suitable for widespread application. This configuration allows the mounting base 110 to rotate 360° relative to the articulated arm 220, thus meeting the requirement for a large lifting angle of the articulated arm 220 relative to the base 210.
[0068] Specifically, the first cylindrical boss 114 and the mounting base 110 can be an integral structure, which facilitates processing, simplifies the connection operation between the first cylindrical boss 114 and the mounting base 110, and is suitable for mass production. Alternatively, the first cylindrical boss 114 and the mounting base 110 can be separate structures, allowing for disassembly and separation for repair or replacement, saving on repair and replacement costs. It is understood that the first cylindrical boss 114 and the mounting base 110 can be connected using bolts, snap-fit joints, mortise and tenon joints, adhesives, welding, or other methods.
[0069] Furthermore, the articulated arm 220 includes a first half-shell and a second half-shell arranged opposite to each other, with two first grooves respectively arranged on the first and second half-shells. Thus, when the mechanical joint 100 is connected to the articulated arm 220, the two first cylindrical bosses 114 of the mounting base 110 can be inserted into the first groove of the first half-shell and the second groove of the second half-shell respectively, and then the first and second half-shells can be connected to achieve a hinge connection between the mounting base 110 and the articulated arm 220. Simultaneously, this arrangement allows the drive unit 120 to be located within the space enclosed by the first and second half-shells of the articulated arm 220, providing good protection for the drive unit 120 and achieving the design requirement of a compact layout between the mechanical joint 100 and the articulated arm 220.
[0070] As shown in Figure 7, in some possible embodiments provided in this disclosure, the outer wall of the nut 140 is provided with a second cylindrical boss 141, and the nut 140 is hinged to the base 210 through the second cylindrical boss 141. The second cylindrical boss 141 can be located on opposite sides of the nut 140, and the base 210 is provided with a second groove. The second cylindrical boss 141 is accommodated in the second groove and can rotate within the second groove. Thus, the nut 140 is hinged to the base 210 through the second cylindrical bosses 141 on both sides. This structure is simple, easy to manufacture, and has low cost, making it suitable for widespread application. Furthermore, this arrangement allows the nut 140 to rotate up to 360° relative to the base 210, thereby meeting the requirement of a larger lifting range of the articulated arm 220 relative to the base 210 and expanding the product's application range.
[0071] Specifically, the second cylindrical boss 141 and the nut 140 can be either integrally formed or separate structures. An integral structure facilitates processing, simplifies the connection process, and is suitable for mass production. A separate structure allows for easy disassembly and replacement of the second cylindrical boss 141 and the nut 140, saving on repair and replacement costs. It is understood that the second cylindrical boss 141 and the nut 140 can be connected using bolts, snap-fit joints, mortise and tenon joints, adhesives, welding, or other methods.
[0072] The axis of the second cylindrical boss 141 is parallel to the axis of the first cylindrical boss 114, which ensures that the nut 140 and the base 210 will not jam, and the mounting seat 110 and the articulated arm 220 will not jam during the relative movement of the lead screw 130 and the nut 140, thus ensuring the smoothness of the lifting and lowering of the articulated arm 220 and improving the smoothness of the lifting and lowering of the mechanical joint 100.
[0073] As shown in Figure 2, in some possible embodiments provided in this disclosure, the mechanical joint 100 further includes: a connecting shaft 170, the axis of which is parallel to the axis of the second cylindrical boss 141 and connected to the base 210; the end of the joint arm 220 near the base 210 is sleeved on the outside of the connecting shaft 170 and rotatably connected to the connecting shaft 170. Thus, a hinge connection between the joint arm 220 and the base 210 can be achieved, resulting in a simple structure that is easy to implement.
[0074] The axis of the connecting shaft 170 is parallel to the axis of the second cylindrical boss 141, which ensures that the nut 140 and the base 210 will not jam, and the joint arm 220 and the base 210 will not jam during the relative movement of the lead screw 130 and the nut 140, thus ensuring the smoothness of the lifting and lowering of the joint arm 220 and improving the smoothness of the lifting and lowering of the mechanical joint 100.
[0075] The connecting shaft 170 can be fixedly connected to the base 210, that is, the connecting shaft 170 can be non-rotating relative to the base 210. Specifically, the connecting shaft 170 can be connected to the base 210 by means of snap-fit structure, plug-in structure, tenon and mortise structure, key, etc.
[0076] The end of the articulated arm 220 near the base 210 can be rotatably connected to the connecting shaft 170 through a bearing, thereby realizing the rotatable connection between the articulated arm 220 and the connecting shaft 170, so as to achieve the hinge connection between the articulated arm 220 and the base 210, which is simple in structure.
[0077] Specifically, the assembly process of the mechanical joint 100 provided in this embodiment is as follows:
[0078] Mounting base 110 is fixed to the housing of drive unit 120 by fasteners 160. Both sides of the connecting boss 131 of lead screw 130 are provided with receiving grooves 135 for accommodating rolling elements 1515. The second washer 1514b of the second rolling assembly 1512 and the second retainer 1513b carrying the rolling element 1515 are installed in the receiving grooves 135 of the second platform 134 of the connecting boss 131. The first retainer 1513a and the first washer 1514a carrying the rolling element 1515 of the first rolling assembly 1511 are installed in the receiving grooves 135 of the first platform 133 of the connecting boss 131. Then, the rolling module 151 and lead screw 130 are installed together into mounting base 110, so that the output shaft of drive unit 120 is inserted into the connecting hole 136 at the first end of lead screw 130. Then, a retaining ring 152 is used to axially limit the rolling assembly 150 to prevent the lead screw 130 from moving axially. Thus, the assembly of mechanical joint 100 is completed.
[0079] Then, the two first cylindrical bosses 114 of the mounting base 110 are inserted into the first groove of the first half-shell and the second groove of the second half-shell of the articulated arm 220, respectively. The first and second half-shells are then connected to achieve the hinge connection between the mounting base 110 and the articulated arm 220. Understandably, the drive unit 120 is pressed against the middle of the articulated arm 220 at this time. Since the nut 140 is hinged to the base 210 via the second cylindrical boss 141, and the second end of the lead screw 130 passes through the nut 140 and is threadedly connected to it, the articulated arm 220 is fitted onto the connecting shaft 170. The articulated arm 220 and the connecting shaft 170 are rotatably connected via bearings. Then, the connecting shaft 170 is fixed to the base 210, thus completing the assembly of the mechanical joint 100, the base 210, and the articulated arm 220. Understandably, the order of some steps in the assembly process can be interchanged, as long as the relevant functions are achieved and the entire assembly is completed. As shown in Figures 1 and 2, the mechanical joint 100 provided in this embodiment has a simple structure. The housing of the drive unit 120 is connected to the mounting base 110, the mounting base 110 is hinged to the joint arm 220 through the second cylindrical boss 141, the nut 140 is hinged to the base 210 through the first cylindrical boss 114, the joint arm 220 is hinged to the base 210 through the connecting shaft 170, and the output shaft of the drive unit 120 is threadedly connected to the nut 140 through the lead screw 130. The three vertices of the movable triangle are the hinge point N between the nut 140 and the base 210, the hinge point O between the joint arm 220 and the base 210, and the hinge point M between the mounting base 110 and the joint arm 220. This allows the output shaft of the drive unit 120 of the mechanical joint 100 to rotate, driving the lead screw 130 and the nut 140 to move relative to each other, enabling the joint arm 220 to be raised or lowered relative to the base 210.
[0080] Specifically, as shown in Figure 2, the hinge point O between the articulated arm 220 and the base 210 can be understood as the axis of the connecting shaft 170. O is fixed to the base 210. The hinge point N between the nut 140 and the base 210 can be understood as the axis of the first cylindrical boss 114 mating with the first groove of the base 210. N is also fixed relative to the base 210. Therefore, the distance ON between O and N remains constant. Similarly, the hinge point M between the mounting base 110 and the articulated arm 220 can be understood as the axis of the second cylindrical boss 141 and the second groove mating structure. M is fixed relative to the articulated arm 220. Therefore, the distance OM between O and M remains constant. When the base 210 is stationary, the lifting and lowering of the articulated arm 220 relative to the base 210 can be achieved simply by adjusting the distance between M and N. Since the lead screw 130 and nut 140 are connected by a threaded structure, when the drive unit 120 drives the lead screw 130 to rotate, it will cause the nut 140 to move away from or towards the drive unit 120, that is, change the distance MN between the hinge point N of the nut 140 and the base 210 and the hinge point M of the mounting base 110 and the articulated arm 220. Therefore, by driving the lead screw 130 and nut 140 to move relative to each other through the drive unit 120, the articulated arm 220 can be raised and lowered relative to the base 210. The structure is simple and the operation is convenient.
[0081] An embodiment of the second aspect of this disclosure provides a robotic arm 200, including a mechanical joint 100 of any embodiment of the first aspect. Since the robotic arm 200 includes the mechanical joint 100 of any of the foregoing embodiments, it possesses all the beneficial technical effects of the aforementioned mechanical joint 100, which will not be elaborated upon here.
[0082] As shown in Figures 1 and 2, specifically, the robotic arm 200 also includes a base 240, on which a base 210 can be mounted. More specifically, the robotic arm 200 may also include a rotary joint 230, which connects the base 240 and the base 210, allowing the base 210 to rotate relative to the base 240. Thus, when the mechanical joint 100 connects the joint arm 220 and the base 210, the rotary joint 230 drives the base 210 to rotate relative to the base 240, thereby rotating the joint arm 220 relative to the base 240 to a suitable angle. It is understood that the robotic arm 200 also includes a robotic hand at its end effector, which can perform grasping and placing operations to pick up or move obstacles, objects, and debris near the cleaning equipment. Therefore, by cooperating with the rotary joint 230 and the mechanical joint 100, the position of the joint arm 220 can be adjusted, thereby adjusting the position of the robotic hand and increasing its range of motion.
[0083] To improve the flexibility of the robotic arm 200's movement, the robotic arm 200 may also include other joints and connecting arms, such as a first flip joint, a second flip joint, a first connecting arm, and a second connecting arm. The base 240 is used to mount the entire robotic arm 200 onto the main body of the cleaning equipment. A rotary joint 230 is mounted on the base 240 and connects the base 240 and the base 210; the rotary joint 230 is used to drive the base 210 to rotate relative to the base 240. A mechanical joint 100 connects the base 210 and the articulated arm 220; the mechanical joint 100 is used to drive the articulated arm 220 to rise and fall relative to the base 210. The first flip joint connects the articulated arm 220 and the first connecting arm; the first flip joint is used to drive the first connecting arm to rise and fall relative to the articulated arm 220. The second flip joint connects the first connecting arm and the second connecting arm; the second flip joint is used to drive the second connecting arm to rise and fall relative to the first connecting arm; the second connecting arm is connected to the robotic arm. In other words, the robotic arm 200 provided in this embodiment has a base 240 and a robotic hand at its two ends, respectively. A rotary joint 230, a mechanical joint 100, a first flip joint, and a second flip joint are connected sequentially from the base 240 to the robotic hand. This increases the range of motion of the robotic hand, thereby improving the cleaning range of the cleaning equipment and expanding the scope of application of the product.
[0084] An embodiment of the third aspect of this disclosure provides a cleaning device, including: the robotic arm 200 provided in any of the foregoing embodiments. Since the cleaning device includes the robotic arm 200 of any of the foregoing embodiments, it has all the technical effects of the aforementioned robotic arm 200, which will not be described in detail here.
[0085] The cleaning equipment includes a main body, and a robotic arm 200 is connected to the main body so that the robotic arm can move with the main body and move to the work station to grasp and move objects.
[0086] The mechanical joint, robotic arm, and cleaning equipment disclosed herein include an robotic arm comprising an articulated arm and a base, and a mechanical joint comprising a mounting base, a drive unit, a lead screw, a nut, and a rolling assembly. The drive unit and the mounting base are connected; the mounting base is hinged to the articulated arm, and the nut is hinged to the base. The first end of the lead screw is located within the mounting base and is poweredly connected to the drive unit; the second end of the lead screw passes through the nut and is threadedly connected to it. The lead screw is connected to a rotating base via the rolling assembly. Thus, the drive unit drives the lead screw to rotate, allowing relative movement between the nut and the lead screw, enabling the articulated arm to rise or fall relative to the base. Because the lead screw is rolled to the mounting base via the rolling assembly (which may include ball bearings or needle rollers), the lead screw can simultaneously withstand large axial thrust and axial tension, as well as a certain radial load. This allows the lead screw to bear a large load simultaneously, reducing damage to the drive unit, improving the stability and reliability of the drive unit and the lead screw's operation, and ultimately increasing the service life and reliability of the mechanical joint.
[0087] This disclosure has been described through the above embodiments; however, it should be understood that the above embodiments are for illustrative purposes only and are not intended to limit this disclosure to the described embodiments. Furthermore, those skilled in the art will understand that this disclosure is not limited to the above embodiments, and many more variations and modifications can be made based on the teachings of this disclosure, all of which fall within the scope of protection claimed by this disclosure. The scope of protection of this disclosure is defined by the appended claims and their equivalents.
Claims
1. A mechanical joint (100) for a robotic arm (200), characterized in that, The mechanical joint (100) includes: The robotic arm (200) comprises a mounting base (110), a drive unit (120), a lead screw (130), a nut (140), and a rolling assembly (150). The mounting base (110) is hinged to the joint arm (220) of the robotic arm (200) and connected to the drive unit (120). The lead screw (130) is rolled to the mounting base (110) via the rolling assembly (150). The first end (137) of the lead screw (130) is located inside the mounting base (110) and is poweredly connected to the drive unit (120). The second end (138) of the lead screw (130) passes through the nut (140) and is threadedly connected to the nut (140). The nut (140) is hinged to the base (210) of the robotic arm (200). The drive unit (120) drives the lead screw (130) to rotate relative to the mounting base (110), so that the lead screw (130) and the nut (140) move relative to each other to drive the articulated arm (220) to rise or fall relative to the base (210).
2. The mechanical joint (100) according to claim 1, wherein, The lead screw (130) is provided with a connecting boss (131) located inside the mounting base (110), and the rolling assembly (150) includes two rolling modules (151), which are respectively arranged on the two platforms (132) of the connecting boss (131). The interior of the mounting base (110) includes two wall surfaces (111) corresponding to the two platform surfaces (132), and the two platform surfaces (132) are respectively tumblingly connected to the corresponding wall surfaces (111) through the rolling module (151).
3. The mechanical joint (100) according to claim 2, wherein, The rolling module (151) includes: a retainer (1513), a rolling element (1515), and a gasket (1514). The retainer (1513) is used to support the rolling element (1515) and is mounted on the table (132). The rolling element (1515) is in contact with the table (132). The gasket (1514) is located between the retainer (1513) and the wall (111).
4. The mechanical joint (100) according to claim 3, wherein, The platform (132) is provided with a receiving groove (135) for accommodating the rolling element (1515).
5. The mechanical joint (100) according to claim 3 or 4, wherein, The rolling assembly (150) also includes a retaining ring (152) inserted between adjacent wall surfaces (111) and the gasket (1514) to limit the axial movement of the lead screw (130) relative to the mounting base (110).
6. The mechanical joint (100) according to claim 5, wherein, The two walls (111) are a first wall (112) and a second wall (113), respectively. The first wall (112) is close to the drive unit (120), and the snap ring (152) is located between the second wall (113) and the adjacent gasket (1514).
7. The mechanical joint (100) according to claim 6, wherein, The first wall surface (112) has a mounting hole (115) and a clearance hole (116). The mechanical joint (100) also includes a fastener (160). The fastener (160) passes through the mounting hole (115) and is connected to the housing of the drive unit (120). The clearance hole (116) is used to avoid the output shaft of the drive unit (120). At least a portion of the gasket (1514) adjacent to the first wall surface (112) contacts the fastener (160).
8. The mechanical joint (100) according to any one of claims 3 to 7, wherein, The connecting boss (131) is spaced apart from the first end (137) of the lead screw (130). The end face of the first end (137) is provided with a connecting hole (136) that matches the output shaft of the drive unit (120). The connecting hole (136) is coaxially arranged with the connecting boss (131).
9. The mechanical joint (100) according to any one of claims 1 to 8, wherein, The outer wall of the mounting base (110) is provided with a first cylindrical boss (114), and the mounting base (110) is hinged to the articulated arm (220) through the first cylindrical boss (114).
10. The mechanical joint (100) according to any one of claims 1 to 9, wherein, The outer wall of the nut (140) is provided with a second cylindrical boss (141), and the nut (140) is hinged to the base (210) through the second cylindrical boss (141).
11. The mechanical joint (100) according to claim 10, further comprising: A connecting shaft (170) is provided, with its axis parallel to the axis of the second cylindrical boss (141) and connected to the base (210). The end of the articulated arm (220) near the base (210) is sleeved on the outside of the connecting shaft (170) and rotatably connected to the connecting shaft (170).
12. A robotic arm (200), characterized in that, include: The mechanical joint (100) as described in any one of claims 1 to 11.
13. A cleaning device, characterized in that, include: The robotic arm (200) as described in claim 12.