Mechanical arm joint

Abstract

The utility model discloses a mechanical arm joint. The problem that a speed reducer assembly in a traditional joint is not compact in transmission effect and structure is solved. The mechanical arm joint comprises a motor assembly, a speed reducer assembly, a first bearing, a second bearing, an output flange and a bottom plate. The motor assembly comprises a motor shaft, a stator and a rotor, the stator sleeves the motor shaft and is fixedly connected with the motor shaft, the rotor sleeves the periphery of the stator, a gap is formed between the rotor and the stator, and the output flange is connected with the motor shaft through a first bearing; the speed reducer assembly comprises a cam, a first steel wheel and a second steel wheel, the cam is fixedly connected with the rotor and connected with the motor shaft through a second bearing, the first steel wheel is fixedly connected with the output flange, and the second steel wheel is fixedly connected with the bottom plate. Through the arrangement, during operation of the motor assembly, the rotor and the cam rotate together, the first steel wheel and the second steel wheel rotate, the first steel wheel drives the output flange to move, and therefore the overall transmission effect is better.

Description

TECHNICAL FIELD

[0001] The utility model relates to robot technical field especially relates to a mechanical arm joint. BACKGROUND

[0002] The joint is an important component of the robot, and different specifications of joints can be used to build different robot configurations, such as mechanical arms and biped robots. The joint mainly consists of a driving motor and a reducer, which provides power by the driving motor and outputs power under the action of the reducer to drive the robot's execution mechanism to move.

[0003] With the development of mechatronics, robot components are developing towards lightweight, integration, intelligence and systematization. The current robots on the market are limited by the size and output capacity of the reducer assembly, and the joint diameter and volume are large and the cost is high. The traditional reducer assembly needs to be driven by a motor shaft, and a stator and a rotor are often needed between the motor shaft and the reducer assembly, so enough space is needed between the motor shaft and the reducer assembly, or the reducer assembly is arranged at one end of the motor shaft. This structure affects the transmission effect of the motor shaft, and the overall structure size of the joint is not compact enough, making it difficult to achieve lightweight design. SUMMARY

[0004] The utility model aims at providing a kind of mechanical arm joint, to solve the problem of the transmission effect and structure of traditional joint reducer assembly not enough compact.

[0005] To solve the above problems, the utility model provides a kind of mechanical arm joint, the mechanical arm joint includes: motor assembly, reducer assembly, first bearing, second bearing, output flange and bottom plate;

[0006] The motor assembly includes motor shaft, stator and rotor, the stator is sleeved on the motor shaft and is fixedly connected with the motor shaft, the rotor is sleeved on the outer periphery of the stator, and the rotor and the stator have a gap, the output flange is connected with the motor shaft by the first bearing, and the motor shaft is fixedly connected with the bottom plate;

[0007] The reducer assembly includes cam, first steel wheel and second steel wheel, the cam is fixedly connected with the rotor, the cam is connected with the motor shaft by the second bearing, the first steel wheel is fixedly connected with the output flange, and the second steel wheel is fixedly connected with the bottom plate.

[0008] Preferably, the mechanical arm joint further comprises a third bearing, and the cam is connected with the bottom plate through the third bearing.

[0009] Preferably, the speed reducer assembly further comprises a flexible gear, the flexible gear comprising a flexible gear first end and a flexible gear second end, the first steel gear and the flexible gear first end being engaged, the second steel gear and the flexible gear second end being engaged.

[0010] Preferably, the cam comprises a cam first end and a cam second end, the cam first end being arranged on the inner side of the flexible gear, the cam second end being arranged on the inner side of the third bearing.

[0011] Preferably, the mechanical arm joint further comprises a driving plate, the driving plate being connected with the motor assembly, the driving plate being used for controlling the operation of the motor assembly.

[0012] Preferably, the mechanical arm joint further comprises an incremental encoder, the incremental encoder being connected with the cam.

[0013] Preferably, the mechanical arm joint further comprises an output encoder, the output encoder being connected with the output flange.

[0014] Preferably, the mechanical arm joint further comprises a brake assembly, the brake assembly comprising an electromagnet and a brake rod, a through hole being formed on the bottom plate, the electromagnet being connected with the bottom plate, the brake rod penetrating through the through hole, one end of the rotor being provided with a groove, the groove and one end of the brake rod being adapted.

[0015] Preferably, the mechanical arm joint further comprises an outer ring assembly and a fourth bearing, the outer ring assembly being sleeved on the outer side of the speed reducer assembly, the outer ring assembly being connected with the bottom plate through the fourth bearing.

[0016] Preferably, the outer ring assembly comprises a first outer ring component, a second outer ring component and a third outer ring component, one end of the first outer ring component being abutted with the output flange, the other end of the first outer ring component being abutted with one end of the second outer ring component, the other end of the second outer ring component being abutted with the third outer ring component, the inner side of the first outer ring component being abutted with the first steel gear, the inner sides of the second outer ring component and the third outer ring component being abutted with the fourth bearing.

[0017] By such setting, the motor shaft and the cam are provided with bearings, the cam is connected with the rotor, in the operation of the motor assembly, the rotor and the cam rotate together, so that the first steel wheel and the second steel wheel rotate, the first steel wheel is fixedly connected with the output flange, the movement of the output flange is driven by the first steel wheel, so that the rotation of the motor shaft and the rotor is better through the overall transmission effect of the reducer assembly; the rotor is sleeved on the outer periphery of the stator, and then the rotor and the cam can be connected, compared with the structure that the stator is arranged between the cam and the rotor, the space required to be preset between the stator and the rotor and the cam is combined into the preset space between the rotor and the stator, so that the internal space of the joint is greatly saved, and the internal structure of the joint is more compact. BRIEF DESCRIPTION OF DRAWINGS

[0018] Figure 1 is a mechanical arm joint structure schematic diagram according to an embodiment of the utility model;

[0019] Figure 2 is according to the first embodiment of the utility model Figure 1 the enlarged view of partial A in it;

[0020] Figure 3 is according to the first embodiment of the utility model Figure 1 the enlarged view of partial B in it.

[0021] Reference Signs:

[0022] 1, motor assembly;101, motor shaft;102, stator;103, rotor;103a, recess;

[0023] 2, reducer assembly;201, cam;201a, cam first end;201b, cam second end;202, first steel wheel;203, second steel wheel;204, flexible wheel;204a, flexible wheel first end;204b, flexible wheel second end;

[0024] 3, first bearing;4, second bearing;5, output flange;6, bottom plate;6a, through hole;7, third bearing;8, driving plate;9, incremental encoder;10, output encoder;

[0025] 11, brake assembly;1101, electromagnet;1102, brake lever;

[0026] 12, outer ring assembly;13, fourth bearing. DETAILED DESCRIPTION

[0027] To make the purpose, technical scheme and advantages of the present application more clear and understandable, the present application will be further described in detail below with reference to the specific embodiments and in conjunction with the drawings. It should be understood that these descriptions are only exemplary and are not intended to limit the scope of the present application. In addition, in the following description, the description of known structures and technologies is omitted to avoid unnecessary confusion of the concept of the present application.

[0028] The layer structure schematic diagrams according to the embodiments of the present application are shown in the drawings. These diagrams are not drawn to scale, in which certain details are exaggerated for clarity, and certain details can be omitted. The shapes of various regions, layers shown in the diagrams and their relative sizes, positional relationships are only exemplary, and in actuality, there can be deviations due to manufacturing tolerances or technical limitations, and a person skilled in the art can additionally design regions / layers with different shapes, sizes, relative positions according to actual needs.

[0029] In the description of the present application, it should be noted that the terms "first", "second", "third" and "fourth" are only for the purpose of description, and cannot be understood as indicating or implying relative importance.

[0030] In conjunction with Figure 1The utility model provides a kind of mechanical arm joint, and mechanical arm joint includes: motor assembly 1, reducer assembly 2, first bearing 3, second bearing 4, output flange 5 and bottom plate 6;Motor assembly 1 includes motor shaft 101, stator 102 and rotor 103, stator 102 is sleeved on motor shaft 101 and is fixedly connected with motor shaft 101, rotor 103 is sleeved on the outer periphery of stator 102, there is gap between rotor 103 and stator 102, output flange 5 is connected with motor shaft 101 by first bearing 3, motor shaft 101 is fixedly connected with bottom plate 6, bottom plate 6 provides support point for motor shaft 101, improves the stability of motor shaft 101;Reducer assembly 2 includes cam 201, first steel wheel 202 and second steel wheel 203, cam 201 is fixedly connected with rotor 103, cam 201 is connected with motor shaft 101 by second bearing 4, first steel wheel 202 is fixedly connected with output flange 5, second steel wheel 203 is fixedly connected with bottom plate 6.Through such setting, bearing is arranged between motor shaft 101 and cam 201, connect cam 201 with rotor 103, in the operation of motor assembly 1, rotor 103 and cam 201 rotate together, so that first steel wheel 202 and second steel wheel 203 rotate, first steel wheel 202 is fixedly connected with output flange 5, first steel wheel 202 is used to drive output flange 5 to move, so that the overall transmission effect of motor shaft 101 and rotor 103 is better after driving output flange 5 by reducer assembly 2;Rotor 103 is sleeved on the outer periphery of stator 102, and then rotor 103 can be fixedly connected with cam 201, compared with the structure form that stator 102 is arranged between cam 201 and rotor 103, the utility model combines the space required between stator 102 and rotor 103 into the preset space between rotor 103 and stator 102, greatly saves joint internal space occupation, so that the internal structure of joint is more compact.

[0031] It should be noted that the specific structure arrangement and size in the joint of the mechanical arm are not limited here, which can meet the above connection relationship and achieve the transmission effect. The motor assembly 1 is used to output rotary kinetic energy, the reducer assembly 2 is used to reduce the high-speed rotation of the motor assembly 1 to the low-speed rotation required by the mechanical arm, while increasing the torque, ensuring the smooth and accurate movement of the mechanical arm. The output flange 5 is used to transmit the rotary kinetic energy reduced by the reducer assembly 2 to the mechanical arm, and the bottom plate 6 is used to fix the reducer assembly 2 in the joint, cooperate with the reducer assembly 2 to reduce the speed of the motor assembly 1, and then expand the output torque of the reducer assembly 2. Here, the fixing method of the stator 102 is not limited, which can be fixedly connected with the motor shaft 101 only, and at the same time, a limiting member is arranged on the bottom plate 6 to fix the position of the stator 102 during the operation of the joint; or the stator 102 and the bottom plate 6 can be fixedly connected. The fixed connection relationship between the cam 201 and the rotor 103 is not limited, in the optional case, the cam 201 and the rotor 103 are bonded or clamped, and in another optional case, the cam 201 and the rotor 103 can be integrally formed, which can meet the requirement that the rotor 103 can drive the cam 201 to rotate during the operation of the motor assembly 1. Here, the connection method of the first steel wheel 202 and the output flange 5 is not limited, which can be clamped, screwed or bonded, etc., which can realize that the output flange 5 is driven to rotate by the first steel wheel 202. The connection method of the second steel wheel 203 and the bottom plate 6 is not limited, which can be clamped, screwed or bonded, etc., which can realize that the relative position between the second steel wheel 203 and the bottom plate 6 is fixed during the operation of the joint. It should be noted that during the operation of the joint, the first steel wheel 202 and the second steel wheel 203 have a speed difference between them after transmitting the rotary power of the motor shaft 101 through the cam 201, and through such a setting, the output flange 5 rotates relative to the bottom plate 6, thereby realizing the movement of the mechanical arm. The speed of the first steel wheel 202 and the second steel wheel 203 is not limited here, which can be greater than the second steel wheel 203, or the second steel wheel 203 can be greater than the first steel wheel 202; the speed difference between the first steel wheel 202 and the second steel wheel 203 is not limited, which can be realized by setting the number difference between the tooth parts of the first steel wheel 202 and the second steel wheel 203, thereby realizing the speed difference between the first steel wheel 202 and the second steel wheel 203, or a flexible gear 204 can be arranged between the cam 201 and the first steel wheel 202 and the second steel wheel 203, and the number of teeth of the flexible gear 204 is set to realize the speed difference between the first steel wheel 202 and the second steel wheel 203.

[0032] In the preferred case, the mechanical arm joint further comprises a third bearing 7, the cam 201 is connected with the bottom plate 6 through the third bearing 7. Through such an arrangement, the cam 201 and the rotor 103 are connected, and in the rotation process, the cam 201 has the first steel wheel 202 and the second bearing 4 as support on the side close to the output flange 5, and the third bearing 7 is arranged on the side close to the bottom plate 6 of the cam 201, so that the bottom plate 6 can also play a supporting role for the cam 201, thereby improving the stability of the movement of the cam 201 and the rotor 103, and at the same time, the integrity of the joint is better.

[0033] In combination Figure 1 And Figure 2 In the preferred case, the reducer assembly 2 further comprises a flexible gear 204, the flexible gear 204 comprises a flexible gear first end 204a and a flexible gear second end 204b, the first steel wheel 202 and the flexible gear first end 204a are engaged, and the second steel wheel 203 and the flexible gear second end 204b are engaged. Through such an arrangement, the flexible gear 204 deforms during the rotation of the cam 201 to transmit power to the first steel wheel 202 and the second steel wheel 203. It should be noted that in the alternative case, the outer side of the flexible gear 204 is provided with a flexible gear 204 tooth portion, preferably, the number of flexible gear 204 tooth portions on the flexible gear first end 204a and the number of flexible gear 204 tooth portions on the flexible gear second end 204b are different, and then the flexible gear first end 204a and the first steel wheel 202 are engaged, and the flexible gear second end 204b and the second steel wheel 203 are engaged, through such an arrangement, during the rotation of the flexible gear 204 driving the first steel wheel 202 and the second steel wheel 203, there is a speed difference between the first steel wheel 202 and the second steel wheel 203. By setting the number of flexible gear 204 tooth portions on the outer side and the number of first steel wheel 202 and second steel wheel 203 tooth portions on the inner side to be different, the speed difference between the first steel wheel 202 and the second steel wheel 203 is realized, and the overall diameter of the first steel wheel 202 and the second steel wheel 203 can be set to be the same, and then when the first steel wheel 202 and the second steel wheel 203 are arranged along the joint axis, the distance between the first steel wheel 202 and the second steel wheel 203 and the joint axis is the same, through such an arrangement, the structure of the flexible gear 204 and the cam 201 is simplified.

[0034] In the preferred case, the cam 201 comprises a cam first end 201a and a cam second end 201b which are integrally arranged, the cam first end 201a is arranged at the inner side of the flexspline 204, and the cam second end 201b is arranged at the inner side of the third bearing 7. Through such arrangement, the cam first end 201a is used to deform the flexspline 204 in the rotation process, thereby driving the first steel wheel 202 and the second steel wheel 203 to rotate, and the cam second end 201b is used to connect with the third bearing 7, ensuring the stability of the cam 201 in the rotation process. In the preferred case, the cross section of the cam first end 201a is arranged in an elliptical shape, or a structure in which a plurality of elliptical long axis centers intersect, and in the rotation process of the cam 201, the elliptical end point of the cam first end 201a deforms the flexspline 204, while there is enough gap between the cam 201 in the short axis direction and the flexspline 204, so that there is enough space for the flexspline 204 to deform. Preferably, the cam second end 201b is arranged in a circular shape which is in close contact with the third bearing 7, ensuring the stability of the cam 201 in the rotation process.

[0035] In combination Figure 1 In the preferred case, the mechanical arm joint further comprises a driving board 8 connected with the motor assembly 1, and the driving board 8 is used to control the operation of the motor assembly 1. In the mechanical arm joint, the driving board 8 receives the instruction of the control system and converts the instruction into the action of the motor assembly 1. Here, the connection relationship between the driving board 8 and the motor assembly 1 is not limited, as long as it can realize the operation of the motor assembly 1. The way in which the driving board 8 controls the operation of the motor assembly 1 is also not limited, which can be through the rotation of the motor shaft 101 or directly control the rotation of the rotor 103.

[0036] In the preferred case, the mechanical arm joint further comprises an incremental encoder 9 connected with the cam 201. The incremental encoder 9 is used to detect and track the rotation of the cam 201, and then obtain the operation of the output flange 5 connected with the reducer assembly 2 according to the operation of the motor assembly 1. Through such arrangement, the action of the mechanical arm can be accurately controlled. Further, the output of the incremental encoder 9 can also be used for a closed-loop control system to ensure the accurate positioning of the mechanical arm. In the preferred case, the mechanical arm joint further comprises an output encoder 10 connected with the output flange 5. The output encoder 10 is used to directly detect and track the position and operation of the output flange 5, and in combination with the data of the incremental encoder 9, the positioning accuracy of the mechanical arm is further improved.

[0037] In combination Figure 1 And Figure 3In the preferred case, the mechanical arm joint further comprises a brake assembly 11, the brake assembly 11 comprises an electromagnet 1101 and a brake lever 1102, a through hole 6a is formed on the bottom plate 6, the electromagnet 1101 is connected with the bottom plate 6, the brake lever 1102 passes through the through hole 6a, one end of the rotor 103 is provided with a groove 103a, and the groove 103a is matched with one end of the brake lever 1102. Through such a setting, the brake assembly 11 can limit the rotation of the rotor 103. When the power is on, the electromagnet 1101 pushes the brake lever 1102 to pass through the through hole 6a, so that the top end of the brake lever 1102 extends into the groove 103a, thereby limiting the rotor 103 from continuing to rotate. When the power is off, the electromagnet 1101 loses the pushing force on the brake lever 1102, and the brake lever 1102 is automatically reset, and the rotor 103 normally operates. Here, the connection relationship between the electromagnet 1101 and the brake lever is not limited, and can be fixed connection or connected through a spring member. When the power is on, the electromagnet 1101 pushes the brake lever 1102 to stretch the spring member; in the power-off state, the spring member resets the brake lever 1102.

[0038] In combination Figure 1 In the preferred case, the mechanical arm joint further comprises an outer ring assembly 12 and a fourth bearing 13, the outer ring assembly 12 is sleeved outside the speed reducer assembly 2, and the outer ring assembly 12 is connected with the bottom plate 6 through the fourth bearing 13. Through such a setting, the outer ring assembly 12 can protect the joint back structure, and the fourth bearing 13 can be arranged to realize the mutual rotation between the bottom plate 6 and the outer ring assembly 12. During the operation of the mechanical arm joint, the mechanical arms at both ends of the joint often need to rotate respectively. At this time, the outer ring assembly 12 can be fixed relative to the position of the joint, so that the two mechanical arms can rotate respectively.

[0039] In the preferred case, the outer ring assembly 12 comprises a first outer ring part, a second outer ring part and a third outer ring part, one end of the first outer ring part abuts against the output flange, the other end of the first outer ring part abuts against one end of the second outer ring part, the other end of the second outer ring part abuts against the third outer ring part, the inner side of the first outer ring part abuts against the first steel wheel 202, and the inner sides of the second outer ring part and the third outer ring part abut against the fourth bearing 13. Through such a setting, the first outer ring part abuts against the first steel wheel 202, so that the first steel wheel 202 and the output flange 5 drive the outer ring assembly 12 to rotate, the second outer ring part and the third outer ring part are connected with the bottom plate 6 through the fourth bearing 13, so that the second outer ring part and the third outer ring part leave a gap between the second steel wheel 203 and the bottom plate 6, which does not affect the movement of the second steel wheel 203, and also makes the outer ring assembly 12 can rotate relative to the bottom plate 6, further improving the flexibility of the mechanical arm joint.

[0040] It should be understood that the above specific embodiments of the present application are only used for illustrative or explanatory purposes of the principles of the present application, and do not constitute a limitation on the present application. Therefore, any modification, equivalent replacement, improvement, etc. made without departing from the spirit and scope of the present application shall be included in the protection scope of the present application. In addition, the appended claims of the present application are intended to cover all changes and modifications falling within the scope and boundaries of the appended claims, or the equivalent forms of such scope and boundaries.

Claims

1. A robot arm joint, characterized in that, The mechanical arm joint comprises a motor assembly (1), a reducer assembly (2), a first bearing (3), a second bearing (4), an output flange (5) and a bottom plate (6); The motor assembly (1) comprises a motor shaft (101), a stator (102) and a rotor (103), the stator (102) is sleeved on the motor shaft (101) and is fixedly connected with the motor shaft (101), the rotor (103) is sleeved on the outer periphery of the stator (102), there is a gap between the rotor (103) and the stator (102), the output flange (5) is connected with the motor shaft (101) through the first bearing (3), and the motor shaft (101) is fixedly connected with the bottom plate (6); The reducer assembly (2) comprises a cam (201), a first steel wheel (202) and a second steel wheel (203), the cam (201) is fixedly connected with the rotor (103), the cam (201) is connected with the motor shaft (101) through the second bearing (4), the first steel wheel (202) is fixedly connected with the output flange (5), and the second steel wheel (203) is fixedly connected with the bottom plate (6).

2. The robotic arm joint of claim 1, wherein, The mechanical arm joint further comprises a third bearing (7), and the cam (201) is connected with the bottom plate (6) through the third bearing (7).

3. The robotic arm joint of claim 2, wherein, The reducer assembly (2) further comprises a flexible gear (204), the flexible gear (204) comprises a flexible gear (204) first end (204a) and a flexible gear (204) second end (204b), the first steel wheel (202) and the flexible gear (204) first end (204a) are engaged, and the second steel wheel (203) and the flexible gear (204) second end (204b) are engaged.

4. The robotic arm joint of claim 3, wherein, The cam (201) comprises a cam (201) first end (201a) and a cam (201) second end (201b) arranged integrally, the cam (201) first end (201a) is arranged on the inner side of the flexible gear (204) in correspondence, and the cam (201) second end (201b) is arranged on the inner side of the third bearing (7) in correspondence.

5. The robotic arm joint of claim 1, wherein, The mechanical arm joint further comprises a driving plate (8), the driving plate (8) is connected with the motor assembly (1), and the driving plate (8) is used for controlling the operation of the motor assembly (1).

6. The robotic arm joint of claim 1, wherein, The mechanical arm joint further comprises an incremental encoder (9), and the incremental encoder (9) is connected with the cam (201).

7. The robotic arm joint of claim 6, wherein, The mechanical arm joint further comprises an output encoder (10), and the output encoder (10) is connected with the output flange (5).

8. The robotic arm joint of claim 1, wherein, The mechanical arm joint further comprises a brake assembly (11), the brake assembly (11) comprises an electromagnet (1101) and a brake lever (1102), a through hole (6a) is formed on the bottom plate (6), the electromagnet (1101) is connected with the bottom plate (6), the brake lever (1102) passes through the through hole (6a), one end of the rotor (103) is provided with a groove (103a), and the groove (103a) and one end of the brake lever (1102) are matched.

9. The robotic arm joint of claim 1, wherein, The mechanical arm joint further comprises an outer ring assembly (12) and a fourth bearing (13), the outer ring assembly (12) is sleeved outside the speed reducer assembly (2), and the outer ring assembly (12) is connected with the bottom plate (6) through the fourth bearing (13).

10. The robotic arm joint of claim 9, wherein, The outer ring assembly (12) comprises a first outer ring part, a second outer ring part and a third outer ring part, one end of the first outer ring part abuts against the output flange, the other end of the first outer ring part abuts against one end of the second outer ring part, the other end of the second outer ring part abuts against the third outer ring part, the inner side of the first outer ring part abuts against the first steel wheel (202), and the inner sides of the second outer ring part and the third outer ring part abut against the fourth bearing (13).

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