Industrial robot drive shaft anti-loosening fastening device

Abstract

The utility model discloses an industrial mechanical arm driving shaft anti -drop fastening device belongs to mechanical connection and fastening technical field, including pivot, shaft shoulder, threaded rod, locking sleeve, joint casing, belleville washer and locking nut, and the mutual cooperation of conical surface boss and conical surface recess is provided between shaft shoulder, locking sleeve and joint casing, the outer wall of locking sleeve is provided with a plurality of stress grooves, the outer wall of conical surface boss all is provided with oil channel, the left side of conical surface boss all is fixedly connected with limit boss. The utility model discloses utilize the conical surface cooperation to convert axial force into radial clamping force, has realized high -strength fastening, and through stress groove dispersion stress simultaneously, through limit boss and belleville washer anti -vibration, through oil channel auxiliary dismounting, solved the problem that connection reliability is insufficient, easy fatigue and dismounting difficult.

Description

Technical Field

[0001] This utility model relates to the field of mechanical connection and fastening technology, and in particular to an anti-detachment fastening device for the drive shaft of an industrial robotic arm. Background Technology

[0002] Industrial robotic arms are key equipment in automated production, and drive shafts, as key components for transmitting power and performing precision movements, need to operate under high load, high torque, and frequent start-stop and reversal conditions, which places extremely high demands on the connection and fastening devices of drive shafts.

[0003] Currently, drive shafts are connected using key or spline connections. While this method can transmit torque, there is an unavoidable gap between the key and the keyway. Under the frequent start-stop impacts and high-frequency vibrations of industrial robotic arms, this gap can cause micro-movements and impacts at the connection points. After long-term operation, this can lead to loosening of the connection, which not only reduces the positioning accuracy of the robotic arm but also poses safety hazards.

[0004] To address the gap issue, existing solutions employ conical locking or interference fit friction fastening structures. While these structures provide a gapless rigid connection, under high loads, stress often concentrates highly on a single contact surface or structural edge, leading to fatigue cracks and shortening the service life of parts. Furthermore, this type of fastening connection, which relies on enormous friction, is extremely difficult to disassemble when maintenance is required, necessitating the use of special tools or even destructive methods, thus increasing maintenance costs and difficulty.

[0005] Furthermore, regardless of the connection method, the locking element itself faces the challenge of preventing loosening in the severe vibration environment of industrial robotic arms. Once the preload fails, the reliability of the entire connection will drop significantly. Therefore, designing a drive shaft fastening device that can provide a gapless rigid connection, effectively disperse stress to resist fatigue, and at the same time prevent vibration loosening and facilitate disassembly and maintenance is an urgent problem to be solved in this field.

[0006] Therefore, this utility model proposes an anti-detachment fastening device for the drive shaft of an industrial robotic arm to address the shortcomings of existing technologies. Utility Model Content

[0007] In view of the problems existing in the prior art of anti-detachment fastening devices for industrial robot arm drive shafts, such as insufficient connection reliability under high torque and high vibration conditions, easy loosening, stress concentration leading to fatigue damage, and difficulty in disassembly after fastening, this utility model aims to provide an industrial robot arm drive shaft anti-detachment fastening device with an improved structure that can effectively solve the above problems.

[0008] This utility model provides an anti-detachment fastening device for the drive shaft of an industrial robotic arm, comprising: a rotating shaft, a shoulder fixedly connected to the right side of the rotating shaft, a threaded rod fixedly connected to the right side of the shoulder, a locking sleeve with a central opening for fitting onto the outer wall of the threaded rod, a joint housing with a central opening for fitting onto the outer wall of the threaded rod and located to the right of the locking sleeve, a Bellwell washer located between the locking sleeve and the joint housing, and a locking nut threadedly connected to the outer wall of the right side of the threaded rod.

[0009] The right side of the shoulder is provided with a conical recess and a conical recess, and the left side of the locking sleeve is fixedly connected with a conical boss and a conical boss that respectively cooperate with the conical recess and the conical recess.

[0010] Furthermore, the right side of the locking sleeve is provided with a conical recess and a conical recess, and the left side of the joint housing is fixedly connected with a conical boss and a conical boss, respectively cooperating with the conical recess and the conical recess on the right side of the locking sleeve. The left and right outer walls of the locking sleeve are provided with multiple stress grooves. The outer walls of the conical boss and the conical boss are provided with oil passages. The left side of the conical boss and the conical boss are fixedly connected with a limiting boss, and the limiting boss abuts against the base surface of the corresponding recess that the conical boss and the conical boss abut.

[0011] Preferably, the outer wall of the oil passage is provided with an oil storage tank, which is connected to the oil passage and is used to store the lubricating oil or hydraulic oil injected into the oil passage.

[0012] Preferably, the length of the first conical boss along the axial direction is different from the length of the second conical boss along the axial direction, thereby forming two independent torque transmission paths between the shoulder, the locking sleeve and the joint housing.

[0013] Preferably, the right top and bottom of the shoulder are provided with the first conical recess, and the right front and rear of the shoulder are provided with the second conical recess.

[0014] Preferably, the first conical boss is fixedly connected to the top and bottom of the left side of the locking sleeve, and the second conical boss is fixedly connected to the front and rear of the left side of the locking sleeve.

[0015] Preferably, the right top and bottom of the locking sleeve are provided with the first conical recess, and the right front and rear of the locking sleeve are provided with the second conical recess.

[0016] Preferably, the multiple stress grooves formed on the locking sleeve are arranged in a circular array, and adjacent stress grooves are connected by an arc transition surface to release stress and avoid stress concentration.

[0017] Preferably, the oil passage extends along the conical surfaces of the first and second conical bosses, and is used to inject high-pressure oil into the mating interface of the conical bosses and conical recesses during disassembly to assist in separation.

[0018] Preferably, the Bellville washer is located between the right end face of the locking sleeve and the left end face of the joint housing, and is used to provide a continuous axial elastic preload after the locking nut is tightened.

[0019] Preferably, the rotating shaft, the shoulder, and the threaded rod are integrally formed.

[0020] This utility model has the following beneficial effects:

[0021] 1. This utility model applies axial force by locking the nut and utilizes the inclined surface cooperation of multiple sets of mutually fitting conical bosses and conical concave surfaces between the shaft shoulder, locking sleeve and joint housing. This solves the problem of loosening and insufficient connection reliability of the drive shaft connection under high torque and high vibration conditions in the prior art. It can convert axial force into huge radial clamping force, and realize a high-strength rigid connection and reliable anti-disengagement.

[0022] 2. This utility model solves the problem of stress concentration in a single cross section in traditional connection methods, which leads to fatigue damage and short service life of parts, by setting conical bosses of different lengths to form a dual torque transmission path and opening stress grooves with arc transitions on the locking sleeve. It effectively disperses torque load, releases internal stress and avoids stress concentration, thereby improving the fatigue resistance and service life of the device.

[0023] 3. This utility model solves the problem of slight loosening of fasteners under high-frequency start-stop and vibration conditions of industrial robotic arms by adding a Bellwell washer to provide elastic preload and setting a limiting boss for mechanical limiting. By combining elastic preload with mechanical limiting, the device can maintain a high degree of fastening stability under long-term severe vibration. Attached Figure Description

[0024] Figure 1 This is a perspective view of the anti-detachment fastening device for the drive shaft of the industrial robotic arm proposed in this utility model;

[0025] Figure 2 This is an exploded view of the anti-detachment fastening device for the drive shaft of the industrial robotic arm proposed in this utility model;

[0026] Figure 3 This is an exploded view of the anti-detachment fastening device for the drive shaft of the industrial robotic arm proposed in this utility model;

[0027] Figure 4 for Figure 2 Enlarged view of point A in the middle.

[0028] Legend:

[0029] 1. Shaft; 2. Shoulder; 3. Locking sleeve; 4. Bellwell washer; 5. Joint housing; 6. Locking nut; 7. Threaded rod; 8. Stress groove; 9. Conical boss one; 10. Oil passage; 11. Oil reservoir; 12. Limiting boss; 13. Conical boss two; 14. Conical recess one; 15. Conical recess two. Detailed Implementation

[0030] To make the objectives, technical solutions, and advantages of this utility model clearer, the technical solutions in the embodiments of this utility model will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only a part of the embodiments of this utility model, and not all of them. All other embodiments obtained by those skilled in the art based on the embodiments of this utility model without creative effort are within the scope of protection of this utility model.

[0031] Example:

[0032] Please refer to Figures 1 to 4 This utility model provides an anti-detachment fastening device for the drive shaft of an industrial robotic arm, which aims to solve the problems of insufficient connection reliability, easy fatigue damage, and difficult maintenance and disassembly of the drive shaft connection structure under high torque and high vibration conditions in the prior art.

[0033] Please refer to Figure 1 , Figure 2 and Figure 3 The anti-detachment fastening device for the drive shaft of the industrial robotic arm includes a rotating shaft 1, a shoulder 2 fixedly connected to the right side of the rotating shaft 1, and a threaded rod 7 fixedly connected to the right side of the shoulder 2. The rotating shaft 1, the shoulder 2, and the threaded rod 7 are integrally formed. A locking sleeve 3 has a central opening to fit onto the outer wall of the threaded rod 7. A joint housing 5 has a central opening to fit onto the outer wall of the threaded rod 7, and the joint housing 5 is located on the right side of the locking sleeve 3. A Bellville washer 4 is located between the locking sleeve 3 and the joint housing 5. Specifically, the Bellville washer 4 is located between the right end face of the locking sleeve 3 and the left end face of the joint housing 5. A locking nut 6 is threadedly connected to the right outer wall of the threaded rod 7. The locking nut 6 is used to press the joint housing 5, the Bellville washer 4, and the locking sleeve 3. The Bellville washer 4 is used to provide a continuous axial elastic preload after the locking nut 6 is locked.

[0034] Please refer to Figure 1 , Figure 2 and Figure 4The right side of the shoulder 2 is provided with a conical recess 14 and a conical recess 15. The left side of the locking sleeve 3 is fixedly connected with a conical boss 9 and a conical boss 13. The conical boss 9 and the conical boss 13 on the left side of the locking sleeve 3 cooperate with the conical recess 14 and the conical recess 15 on the right side of the shoulder 2, respectively. At the same time, the right side of the locking sleeve 3 is provided with a conical recess 14 and a conical recess 15. The left side of the joint housing 5 is fixedly connected with a conical boss 9 and a conical recess 15. The second boss 13, the first conical boss 9 and the second conical boss 13 on the left side of the joint housing 5 respectively cooperate with the first conical recess 14 and the second conical recess 15 on the right side of the locking sleeve 3. This multi-set conical surface cooperation structure, when the locking nut 6 applies axial pressure, uses the inclined plane effect to forcibly convert the axial force into huge radial expansion and contraction force, so that the locking sleeve 3 and the rotating shaft 1 and the locking sleeve 3 and the joint housing 5 form a tight fit, realizing high-strength fastening and anti-loosening.

[0035] The right top and bottom of the shoulder 2 are provided with conical recesses 14, and the right front and rear of the shoulder 2 are provided with conical recesses 15. The left top and bottom of the locking sleeve 3 are fixedly connected with conical bosses 9, and the left front and rear of the locking sleeve 3 are fixedly connected with conical bosses 13. The right top and bottom of the locking sleeve 3 are provided with conical recesses 14, and the right front and rear of the locking sleeve 3 are provided with conical recesses 15. The left top and bottom of the joint housing 5 are fixedly connected with conical bosses 9, and the left front and rear of the joint housing 5 are fixedly connected with conical bosses 13. The length of conical bosses 19 in the axial direction is different from that of conical bosses 13 in the axial direction. This forms two independent torque transmission paths between the shoulder 2, the locking sleeve 3 and the joint housing 5, which disperses the torque and avoids the stress from concentrating sharply in a single cross section.

[0036] For a preferred embodiment, please refer to Figure 2 and Figure 3 Multiple stress grooves 8 are arranged in a ring array on the left and right outer walls of the locking sleeve 3, and adjacent stress grooves 8 are connected by an arc transition.

[0037] For a preferred embodiment, please refer to Figure 4 The limiting boss 12, which is fixedly connected to the left side of the conical boss 9 and the conical boss 13, abuts against the base surface of the corresponding concave platform that mates with the conical boss 9 and the conical boss 13.

[0038] For a preferred embodiment, please refer to Figure 4 Oil passages 10 are opened on the outer walls of conical boss 19 and conical boss 213, extending along the conical surfaces of conical boss 19 and conical boss 213, and are used to inject high-pressure oil into the mating interface of the conical boss and the conical recess during disassembly to assist separation.

[0039] For a preferred embodiment, please refer to Figure 4 An oil storage tank 11 is provided on the outer wall of the oil passage 10. The oil storage tank 11 is connected to the oil passage 10 and is used to store the lubricating oil or hydraulic oil injected into the oil passage 10.

[0040] For a preferred embodiment, please refer to Figure 1 and Figure 2 The Bellville washer 4 is located between the right end face of the locking sleeve 3 and the left end face of the joint housing 5, and is used to provide a continuous axial elastic preload after the locking nut 6 is tightened.

[0041] Working principle:

[0042] During installation and tightening, the locking nut 6 is rotated. The locking nut 6 is connected by the threaded rod 7 and applies axial pressure to the joint housing 5, Bellville washer 4 and locking sleeve 3. Since the shoulder 2, locking sleeve 3 and joint housing 5 are provided with mutually cooperating conical boss 19, conical boss 213 and conical concave platform 14 and conical concave platform 215, the axial pressure is forcibly converted into huge radial expansion and contraction force by utilizing the inclined surface effect of the conical surface. This makes the locking sleeve 3 tightly hug the rotating shaft 1, and the locking sleeve 3 and joint housing 5 also achieve a gapless fit, thereby achieving high-strength fastening, anti-loosening and torque transmission.

[0043] During fastening and operation, the Bellville washer 4 is compressed, providing a continuous axial elastic preload to effectively compensate for loosening caused by vibration or thermal expansion and contraction. Multiple stress grooves 8 on the locking sleeve 3 allow the locking sleeve 3 to undergo slight deformation to release internal stress when subjected to huge radial forces. The arc transition between the stress grooves 8 avoids stress concentration. The limiting boss 12 provides mechanical limiting, further preventing loosening under high-frequency vibration. The conical boss 1 9 and conical boss 2 13 of different lengths form two independent torque transmission paths, dispersing the load and improving the fatigue life of the parts.

[0044] When disassembly is required, first loosen the locking nut 6. Since the conical surface fit is extremely tight, high-pressure oil or lubricating oil can be injected into the oil passage 10. The oil extends along the conical surface through the oil passage 10 into the mating interface. The hydraulic or lubricating action assists in the separation of the conical boss 9 and conical boss 13 from the conical recess 14 and conical recess 15. The oil reservoir 11 can be used to store the oil to assist in the separation process and achieve rapid disassembly of the device.

Claims

1. An anti-detachment fastening device for the drive shaft of an industrial robotic arm, comprising: The rotating shaft (1), locking sleeve (3), joint housing (5), Bellville washer (4) and locking nut (6) are provided. The rotating shaft (1) is fixedly connected to the right side of a shoulder (2). The right side of the shoulder (2) is fixedly connected to a threaded rod (7). The locking sleeve (3) has a central hole to fit onto the outer wall of the threaded rod (7). The joint housing (5) has a central hole to fit onto the outer wall of the threaded rod (7) and is located on the right side of the locking sleeve (3). The Bellville washer (4) is located between the locking sleeve (3) and the joint housing (5). The locking nut (6) is threaded to the right outer wall of the threaded rod (7) and is used to press the joint housing (5), Bellville washer (4) and locking sleeve (3). The feature is that a conical recess 1 (14) and a conical recess 2 (15) are provided on the right side of the shoulder (2), and a conical boss 1 (9) and a conical boss 2 (13) are fixedly connected to the left side of the locking sleeve (3), respectively cooperating with the conical recess 1 (14) and the conical recess 2 (15). The right side of the locking sleeve (3) is provided with a conical recess 1 (14) and a conical recess 2 (15), and the left side of the joint housing (5) is fixedly connected with the conical recess 1 (14) and the conical boss 2 (15) on the right side of the locking sleeve (3). The conical boss one (9) and conical boss two (13) are matched with the concave platform two (15). Multiple stress grooves (8) are provided on the left and right outer walls of the locking sleeve (3). Oil passages (10) are provided on the outer walls of the conical boss one (9) and the conical boss two (13). A limiting boss (12) is fixedly connected to the left side of the conical boss one (9) and the conical boss two (13). The limiting boss (12) abuts against the base surface of the corresponding concave platform matched by the conical boss one (9) and the conical boss two (13).

2. The anti-detachment fastening device for the drive shaft of an industrial robotic arm according to claim 1, characterized in that, An oil storage tank (11) is provided on the outer wall of the oil passage (10). The oil storage tank (11) is connected to the oil passage (10) and is used to store the lubricating oil or hydraulic oil injected into the oil passage (10).

3. The anti-detachment fastening device for the drive shaft of an industrial robotic arm according to claim 1, characterized in that, The length of the first conical boss (9) along the axial direction is different from the length of the second conical boss (13) along the axial direction, thereby forming two independent torque transmission paths between the shoulder (2), the locking sleeve (3) and the joint housing (5).

4. The anti-detachment fastening device for the drive shaft of an industrial robotic arm according to claim 1, characterized in that, The right top and bottom of the shoulder (2) are provided with the first conical recess (14), and the right front and rear of the shoulder (2) are provided with the second conical recess (15).

5. The anti-detachment fastening device for the drive shaft of an industrial robotic arm according to claim 1, characterized in that, The top and bottom left side of the locking sleeve (3) are fixedly connected to the first conical boss (9), and the front and rear left side of the locking sleeve (3) are fixedly connected to the second conical boss (13).

6. The anti-detachment fastening device for the drive shaft of an industrial robotic arm according to claim 1, characterized in that, The right top and bottom of the locking sleeve (3) are provided with the first conical recess (14), and the right front and rear of the locking sleeve (3) are provided with the second conical recess (15).

7. The anti-detachment fastening device for the drive shaft of an industrial robotic arm according to claim 1, characterized in that, The multiple stress grooves (8) formed on the locking sleeve (3) are arranged in a ring array, and adjacent stress grooves (8) are connected by an arc transition to release stress and avoid stress concentration.

8. The anti-detachment fastening device for the drive shaft of an industrial robotic arm according to claim 1, characterized in that, The oil passage (10) extends along the conical surfaces of the first conical boss (9) and the second conical boss (13) and is used to inject high-pressure oil into the mating interface of the conical boss and the conical recess during disassembly to assist in separation.

9. The anti-detachment fastening device for the drive shaft of an industrial robotic arm according to claim 1, characterized in that, The Bellville washer (4) is located between the right end face of the locking sleeve (3) and the left end face of the joint housing (5) to provide a continuous axial elastic preload after the locking nut (6) is tightened.

10. The anti-detachment fastening device for the drive shaft of an industrial robotic arm according to claim 1, characterized in that, The rotating shaft (1), the shoulder (2), and the threaded rod (7) are integrally formed.

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