Explosion-proof multi-degree-of-freedom mechanical arm

Abstract

The explosion-proof multi-degree-of-freedom mechanical arm disclosed by the application belongs to the field of mechanical arms and mainly comprises explosion-proof motors and end executing mechanisms in transmission connection with the explosion-proof motors. The explosion-proof motors are six in number and are sequentially a first shaft motor vertically rotatably installed on an installation base; the first shaft motor and a second shaft motor are rotatably installed together with their rotation shafts being perpendicular to each other; a rotation shaft of a third shaft motor is parallel to a rotation shaft of the second shaft motor and is fixedly connected through a large arm, the rotation shaft of the third shaft motor is fixedly connected with a fourth shaft motor through a small arm, the fourth shaft motor, a fifth shaft motor and a sixth shaft motor are sequentially rotatably connected together, the rotation shaft of the fifth shaft motor is perpendicular to the rotation shafts of the fourth shaft motor and the sixth shaft motor at the same time, and the end executing mechanism is installed on the rotation shaft of the sixth shaft motor. The explosion-proof multi-degree-of-freedom mechanical arm has simple and reliable structure, good explosion-proof performance and excellent flexibility, and is very suitable for use in explosive environments.

Description

TECHNICAL FIELD

[0001] The present application relates to the technical field of mechanical arm, in particular to a flameproof multi-degree-of-freedom mechanical arm. BACKGROUND

[0002] With the gradual improvement of the degree of industrial automation in China, collaborative industrial robot arms have been widely applied. In some potentially explosive hazardous environments, such robot arms are mostly realized by adopting the positive pressure protection mode to meet the explosion-proof requirements. However, the positive pressure control system has some inherent defects, such as the need for continuous air supply, the inconvenience of moving the complete positive pressure equipment, the complexity of electrical lines and high-pressure gas pipeline, and the laborious and time-consuming installation and debugging work, which limits the application of collaborative robot arms to a certain extent.

[0003] On the other hand, the robot arm in a flameproof environment has higher flexibility requirements compared to other environments. Because in a flameproof environment, the space available for operation is more limited, the robot arm needs to be driven more sensitively to rotate and then move to the working position. The positive pressure explosion-proof motor is a method of maintaining the pressure of the protective gas inside the motor housing higher than the external atmospheric pressure to prevent the entry of external explosive gas into the housing. The motor housing needs to be filled with protective gas to maintain the required positive pressure value. Generally, there should be two or more supply sources. In this way, if the supply source of protective gas fails and the motor must continue to be powered, the other supply source can be switched. Therefore, each supply source must ensure the supply pressure and supply amount. The inlet of the protective gas and the outlet of the exhaust gas should be set in the non-dangerous place. Therefore, the installation environment and the use of supporting equipment are required to be extremely high. Under the condition of multi-degree-of-freedom, the number of motors of the robot arm increases, which inevitably leads to an increase in the corresponding supporting gas pipeline and pipeline sealing facilities. Not only is it difficult to install, maintain and use, but it also easily interferes with the normal operation of the robot arm, thereby limiting the normal free movement of the robot arm in a flameproof environment. SUMMARY

[0004] In view of the above technical status, the purpose of the present application is to provide a flameproof multi-degree-of-freedom mechanical arm. The six flameproof motors are connected in a clever transmission manner to form multiple degrees of freedom, which has extremely high flexibility. The motor is flameproof and has intrinsic safety, so it does not need to be equipped with a complex protective gas pressure environment, and it has wider adaptability.

[0005] In order to achieve the above object, the application adopts a flameproof multi-degree-of-freedom mechanical arm, which comprises a flameproof motor and an end execution mechanism in transmission connection with the flameproof motor, the flameproof motor is provided with six, which are sequentially a first shaft motor vertically rotatably installed on an installation base; the first shaft motor and the second shaft motor are rotatably installed together, and the rotation shafts of the two are perpendicular to each other; the rotation shaft of the third shaft motor is parallel to the rotation shaft of the second shaft motor and is fixedly connected through a large arm, the rotation shaft of the third shaft motor is fixedly connected with the fourth shaft motor through a small arm, the fourth shaft motor, the fifth shaft motor and the sixth shaft motor are sequentially rotatably connected together, wherein the rotation shaft of the fifth shaft motor is perpendicular to the rotation shafts of the fourth shaft motor and the sixth shaft motor at the same time, and the end execution mechanism is installed on the rotation shaft of the sixth shaft motor.

[0006] Further, one end of the small arm has a sleeve part coaxially fixed on the rotation shaft of the third shaft motor.

[0007] Further, the rotatable installation structure of the two motors opposite to each other is that the rotation shaft of one of the motors is rotatably fitted in a closed shell, the closed shell is fixed on the side wall of the other motor, a gear ring is fixed in the closed shell, and the gear ring is in transmission connection with the driving gear on the rotation shaft of the one motor through a variable speed gear;

[0008] The outer side of the closed shell is further fixed with a plurality of -shaped limiting blocks, all the limiting blocks are arranged in an annular array around the closed shell, and the edge of the installation flange of the one motor is located in the limiting blocks, so that the motor can rotate on the side of the closed shell under the gear transmission.

[0009] Further, a circle of ball bearings is arranged between the flange and the surface of the closed shell.

[0010] Further, the end execution mechanism comprises a mechanical claw, the mechanical claw comprises an installation disc coaxially installed on the rotation shaft of the sixth shaft motor, a driving disc, the installation disc is fixed on the flange end surface of the sixth shaft motor, a plurality of radial sliding columns are arranged in an annular array in the installation disc, each sliding column is elastically slidably installed in the installation disc through a tension spring, and a horizontal finger lever is fixed on one end of the sliding column extending out of the installation disc;

[0011] The driving disc is coaxially fixedly sleeved on the rotation shaft, a plurality of arc-shaped holes are arranged in an annular array on the driving disc, a transmission pin is installed in each arc-shaped hole, one end of the transmission pin is fixed on the sliding column, so that when the driving disc rotates on the surface of the installation disc under the driving of the rotation shaft, all the sliding columns are synchronously extended / withdrawn into the installation disc through the transmission pin.

[0012] Further, the end of the rotating shaft has a threaded section, a lock nut is threadedly connected to the threaded section, and the lock nut is elastically pressed against the driving disc through an elastic gasket.

[0013] Further, a roller is rotatably sleeved on the rotating sleeve in the arc-shaped hole.

[0014] Further, the end of the cross rod is further connected with a caliper, the caliper is fixed with a friction pad on the side of the installation disc, and the caliper can move relative to the cross rod.

[0015] Further, a rotating column is coaxially rotatably installed in the cross rod, one end of the rotating column is fixed with a threaded column, and the free end of the threaded column is coaxially and threadedly connected in the caliper.

[0016] The cross rod is fixed with a curved arm, the end of the curved arm is fixed with a groove-shaped block, the groove-shaped block is in linear sliding connection with the caliper, so that the caliper moves linearly under the limitation of the groove-shaped block when the rotating column rotates.

[0017] Further, an elastic telescopic connecting rod parallel to the radial direction of the installation disc is further fixed on the edge of the installation disc, the end of the elastic telescopic connecting rod is fixed on the inner side wall of an arc-shaped rack, and the arc-shaped rack is always in meshing transmission with a driven gear installed on the rotating column under the elastic pushing force of the elastic telescopic connecting rod.

[0018] Beneficial effects: the six intrinsically safe explosion-proof motors are used for transmission connection and assembly, multiple degrees of freedom are formed, six-axis motor linkage is formed, the end execution element has stronger movement execution capability, meanwhile, the explosion-proof performance is good without complicated protection gas pipeline, a series of pipeline accessories are not installed, the normal operation of the mechanical arm is not disturbed, and the mechanical arm can work more freely in the explosive environment. BRIEF DESCRIPTION OF DRAWINGS

[0019] The following are some specific embodiments of the present application, which are described in the drawings of the present application, mainly the principle of the specific operation execution structure or method of some embodiments of the present application, but this does not mean that the physical structure or operation steps of the present application can only be shown in the drawings.

[0020] Figure 1 is a structural schematic view of the present application;

[0021] Figure 2 is a cross-sectional view of the rotating installation structure between the two motors of the present application;

[0022] Figure 3 is a schematic view of the installation structure of the end execution mechanism and the motor.

[0023] Figure 4 is Figure 3 a sectional view of A-A in

[0024] Figure 5 is a schematic view of the arc-shaped rack.

[0025] In the figure, the mounting base 1, the first shaft motor 2, the second shaft motor 3, the large arm 4, the third shaft motor 5, the small arm 6, the fourth shaft motor 7, the fifth shaft motor 8, the sixth shaft motor 9, the end effector 10, the rotating shaft 11, the driving gear 12, the gear shift 13, the gear ring 14, the limit block 15, the flange 16, the ball 17, the mounting disc 18, the sliding column 19, the rotating column 20, the tension spring 21, the driving disc 22, the arc-shaped hole 23, the transmission pin 24, the roller 25, the locking nut 26, the elastic pad 27, the elastic telescopic connecting rod 28, the arc-shaped rack 29, the driven gear 30, the threaded column 31, the slot-shaped block 32, the caliper 33, the friction pad 34, the curved arm 35, the cross finger lever 36. DETAILED DESCRIPTION

[0026] The embodiments of the present application will be described in detail below, some core features of the embodiments will be specifically shown in the drawings, wherein the same or similar reference numerals represent the same or similar technical features, or structures or steps, processes having similar functions. Based on these embodiments, the general skilled person can replace other embodiments without making creative efforts, which are also within the protection scope of the present application.

[0027] Please refer to the figure, a kind of explosion-proof multi-degree-of-freedom mechanical arm is shown, mainly including explosion-proof motor and with explosion-proof motor transmission connection end effector 10, also equipped with a special mechanical arm electrical control part, connected with mechanical arm body through cable, used for manual control, calibration and other operations of mechanical arm, when using, connected with electrical control part through cable; End effector 10 is generally used to grab the corresponding parts, or hold the corresponding tool. In the above elements, the distribution box shell of the corresponding electrical control part, and the shell of the hand controller for controlling the mechanical arm at any time, are all explosion-proof structure, to avoid explosive gas entering the inside, because of electric spark explosion. In detail, the difference is that the explosion-proof motor in the embodiment is six, in turn, the first shaft motor 2 is vertically installed on a mounting base 1, this mounting base 1 can be fixed on the required equipment or component, to realize the installation of the whole mechanical arm. Specifically, as shown in the figure, the first shaft motor 2 is vertically installed on the mounting base 1, the second shaft motor 3 is horizontally installed on the first shaft motor 2, the large arm 4 is installed on the second shaft motor 3, the third shaft motor 5 is installed on the large arm 4, the small arm 6 is installed on the third shaft motor 5, the fourth shaft motor 7 is installed on the small arm 6, the fifth shaft motor 8 is installed on the fourth shaft motor 7, the sixth shaft motor 9 is installed on the fifth shaft motor 8, the end effector 10 is installed on the sixth shaft motor 9, the rotating shaft 11 is installed on the end effector 10, the driving gear 12 is installed on the rotating shaft 11, the gear shift 13 is installed on the driving gear 12, the gear ring 14 is installed on the gear shift 13, the limit block 15 is installed on the gear ring 14, the flange 16 is installed on the limit block 15, the ball 17 is installed on the flange 16, the mounting disc 18 is installed on the ball 17, the sliding column 19 is installed on the mounting disc 18, the rotating column 20 is installed on the sliding column 19, the tension spring 21 is installed on the rotating column 20, the driving disc 22 is installed on the tension spring 21, the arc-shaped hole 23 is installed on the driving disc 22, the transmission pin 24 is installed on the arc-shaped hole 23, the roller 25 is installed on the transmission pin 24, the locking nut 26 is installed on the roller 25, the elastic pad 27 is installed on the locking nut 26, the elastic telescopic connecting rod 28 is installed on the elastic pad 27, the arc-shaped rack 29 is installed on the elastic telescopic connecting rod 28, the driven gear 30 is installed on the arc-shaped rack 29, the threaded column 31 is installed on the driven gear 30, the slot-shaped block 32 is installed on the threaded column 31, the caliper 33 is installed on the slot-shaped block 32, the friction pad 34 is installed on the caliper 33, the curved arm 35 is installed on the friction pad 34, the cross finger lever 36 is installed on the curved arm 35. Figure 1, the first shaft motor 2 and the second shaft motor 3 are rotatably mounted together, and the rotating shafts 11 of the two are perpendicular to each other, the first shaft motor 2 can be rotatably mounted on the mounting base 1, when the motor is started, the whole mechanical arm can rotate based on the rotation of the first shaft motor 2 relative to the mounting base 1. When making, the rotating shaft 11 of the third shaft motor 5 is parallel to the rotating shaft 11 of the second shaft motor 3, and is fixedly connected through a large arm 4, the rotating shaft 11 of the third shaft motor 5 is fixedly connected with the fourth shaft motor 7 through a small arm 6, the fourth shaft motor 7, the fifth shaft motor 8 and the sixth shaft motor 9 are sequentially rotatably connected together, forming a similar └ type layout, when installing, the rotating shaft 11 of the fifth shaft motor 8 is perpendicular to the rotating shaft 11 of the fourth shaft motor 7 and the sixth shaft motor 9, and the end effector 10 is mounted on the rotating shaft 11 of the sixth shaft motor 9, through the rotating shaft 11 of the six motors, multi-axis rotation can be realized, the installation structure is extremely simple and has great flexibility.

[0028] In specific practice, as Figure 1 , one end of the small arm 6 has a sleeve part, the sleeve part is coaxially fixed on the rotating shaft 11 of the third shaft motor 5, one end of the sleeve part is closed, and the other end is butted on the flange 16 end face of the third shaft motor 5, and is in dynamic sealing connection with the flange 16 end face.

[0029] As one of the other embodiments, for the rotating installation of the two motors relative to each other, as Figure 2 shown, the specific structure is that the rotating shaft 11 of one of the motors is rotatably mounted in a closed shell, which can be a cylindrical shell, the closed shell is fixed on the side wall of the other motor, a gear ring 14 is fixed in the closed shell, the gear ring 14 is in transmission connection with the driving gear 12 on the rotating shaft 11 of the aforementioned one motor (hereinafter referred to as one motor) through a plurality of variable speed gears 13, and then when the one motor rotates, because the closed shell and the gear ring 14 are fixed and do not move, the one motor as a whole will rotate relative to the other motor when the rotating shaft 11 of the one motor rotates. In order to better realize the rotary motion, the outer surface of the closed shell is also fixed with a plurality of ┌ shaped limit blocks 15, all the limit blocks 15 are arranged in a ring around the closed shell, and the edge of the mounting flange 16 of one of the motors is located in the limit block 15, so as to realize the relative rotating installation of the two motors, and make the motor rotate on the side surface of the closed shell under the gear transmission. In order to improve the flexibility of rotation, a circle of ball bearings 17 is arranged between the flange 16 and the surface of the closed shell, so as to reduce the friction force when rotating.

[0030] As another embodiment, on the basis of the above structure, the end effector 10 includes a mechanical gripper, which specifically includes the following components: Figures 3-4, coaxially installed on the rotating shaft 11 of the sixth shaft motor 9, the mounting disc 18 and the driving disc 22, wherein the mounting disc 18 is fixed on the end face of the flange 16 of the sixth shaft motor 9 and can be connected by bolts. There are a plurality of radially arranged sliding columns 19 in the inner ring array of the mounting disc 18, each sliding column 19 is elastically slidably installed in the mounting disc 18 by a tension spring 21, one end of the sliding column 19 extends out of the mounting disc 18 and is fixed with a horizontal finger lever 36, the tension spring 21 always bears tension when the sliding column 19 extends out, maintains stability, and facilitates rapid retraction and reset into the mounting disc 18. In addition, the driving disc 22 is coaxially fixedly sleeved on the rotating shaft 11, and the driving disc 22 has a plurality of arc-shaped holes 23 in the ring array, each arc-shaped hole 23 is provided with a transmission pin 24, one end of the transmission pin 24 is fixed on the sliding column 19, so that when the driving disc 22 rotates on the surface of the mounting disc 18 driven by the rotating shaft 11, all the sliding columns 19 are synchronously extended / retracted into the mounting disc 18 through the transmission pin 24, so as to grab the corresponding parts or tools.

[0031] Specifically, when installing, as Figure 3 , the end of the rotating shaft 11 has a threaded section, a lock nut 26 is threadedly connected on the threaded section, the lock nut 26 is elastically pressed and transmitted in the axial direction by the elastic gasket and the driving disc 22, and the tightness of the relative rotation between the driving disc 22 and the mounting disc 18 can be adjusted by adjusting the tightening degree of the lock nut 26. When manufacturing, the transmission pin 24 is rotatably sleeved with a roller 25 at the part in the arc-shaped hole 23, the roller 25 is in rolling connection with the arc-shaped hole 23, so as to reduce the friction force during driving.

[0032] As a more detailed factual structure, as Figure 3 , the end of the horizontal finger lever 36 is also connected with a caliper 33, the caliper 33 is fixed with a friction pad 34 on one side of the inner side of the mounting disc 18, the clamping friction is improved, and the caliper 33 can move relative to the horizontal finger lever 36 to adapt to parts and tools of different sizes.

[0033] As a more optimal implementation structure, as Figures 3-4As shown, the rotating column 20 is coaxially installed in the horizontal finger 36, and is installed in situ for rotation. A threaded column 31 is fixed at one end of the rotating column 20. The free end of the threaded column 31 is coaxially and threadedly installed in the caliper 33. Specifically, the caliper 33 has a threaded through hole for installing the threaded column 31. At the same time, a curved arm 35 is fixed on the horizontal finger 36. A slot-shaped block 32 is fixed at the end of the curved arm 35. The slot-shaped block 32 can have a Π-shaped cross section. The slot-shaped block 32 is linearly slidably connected with the caliper 33, i.e. is arranged on the side of the caliper 33 away from the inner side of the mounting disc 18, so that when the rotating column 20 rotates, the threaded column 31 rotates, and the caliper 33 linearly moves under the limitation of the slot-shaped block 32, so as to realize the moving away or approaching of the caliper 33 relative to the horizontal finger 36, to adapt to the clamping of parts or tools of different sizes.

[0034] Finally, the optimal structure design in the embodiment is described in Figure 3 At the edge of the mounting disc 18, an elastic expansion connecting rod 28 parallel to the radial direction of the mounting disc 18 is also fixed. The elastic expansion connecting rod 28 itself can axially expand and has excellent elasticity. The end of the elastic expansion connecting rod 28 is fixed on the inner side wall of an arc-shaped rack 29, and is integrally connected with the arc-shaped rack 29. The structure of the arc-shaped rack 29 is shown in Figure 5 When the driving disc 22 rotates to drive all the sliding columns 19 to extend out of the mounting disc 18, the elastic expansion connecting rod 28 rotates together. Because the elastic thrust of the elastic expansion connecting rod 28 always exists, the arc-shaped rack 29 always meshes with the driven gear 30 installed on the rotating column 20 under the elastic thrust of the elastic expansion connecting rod 28, so as to realize the rotation of the arc-shaped rack 29 away from the center of the mounting disc 18, and drive the rotating column 20 to rotate, so that the caliper 33 extends farther, and the entire mechanical claw not only has a larger grabbing radius, but also has a larger horizontal length or axial length of the grabbed target, i.e. more perfectly matches some large-sized parts or workpieces.

[0035] The above series of specific implementation details only show some preferred embodiments in the inventive concept, and cannot limit the protection scope of the claims of the present application. Based on the understanding of the above embodiments, the person skilled in the art can simply change the design idea by referring to the basic principles recorded in the claims of the present application, but these changes still belong to the protection scope of the invention.

Claims

1. A flameproof multi-degree-of-freedom robotic arm, comprising a flameproof motor and an end actuator (10) connected to the flameproof motor, characterized in that: The flameproof motors are provided with six, and the first axis motor (2) is vertically rotatably mounted on a mounting base (1); the first axis motor (2) and the second axis motor (3) are relatively rotatably mounted together, and the rotation shafts (11) of the two are perpendicular to each other; the rotation shaft (11) of the third axis motor (5) is parallel to the rotation shaft (11) of the second axis motor (3) and is fixedly connected via a large arm (4); the rotation shaft (11) of the third axis motor (5) is fixedly connected to the fourth axis motor (7) via a small arm (6); the fourth axis motor (7), the fifth axis motor (8), and the sixth axis motor (9) are rotatably connected together in sequence, wherein the rotation shaft (11) of the fifth axis motor (8) is perpendicular to the rotation shafts (11) of the fourth axis motor (7) and the sixth axis motor (9) at the same time, and the end actuator (10) is mounted on the rotation shaft (11) of the sixth axis motor (9); The rotating mounting structure of two motors rotating relative to each other is as follows: the rotating shaft (11) of one of the motors is rotatably mounted in a closed shell, the closed shell is fixed on the side wall of the other motor, a ring gear (14) is fixed in the closed shell, and the ring gear (14) is transmission-connected to the driving gear (12) on the rotating shaft (11) of the one of the motors through a speed change gear (13); The outer side of the closed shell is also fixed with a plurality of ﹁-shaped limit blocks (15), all of which are arranged in a circular array around the closed shell. The edge of the mounting flange (16) of one of the motors is located within the limit block (15), so that the motor can rotate on the side of the closed shell under gear transmission; a circle of balls (17) is provided between the flange (16) and the surface of the closed shell.

2. The flameproof multi-degree-of-freedom robotic arm according to claim 1, characterized in that: One end of the small arm (6) has a sleeve portion, and the sleeve portion is coaxially fixed on the rotating shaft (11) of the third-axis motor (5).

3. The flameproof multi-degree-of-freedom robotic arm according to claim 1, characterized in that: The end actuator (10) includes a mechanical claw, which includes a mounting plate (18) and a driving plate (22) coaxially mounted on the rotating shaft (11) of the sixth-axis motor (9), wherein the mounting plate (18) is fixed on the end face of the flange (16) of the sixth-axis motor (9), and a plurality of radially arranged sliding columns (19) are arranged in an annular array within the mounting plate (18), each sliding column (19) is elastically slidably mounted within the mounting plate (18) by a tension spring (21), and one end of the sliding column (19) extends out of the mounting plate (18) and is fixed with a horizontal finger rod (36); The driving disc (22) is coaxially fixedly sleeved on the rotating shaft (11). The driving disc (22) has a plurality of arc-shaped holes (23) in an annular array. A transmission pin (24) is installed in each arc-shaped hole (23). One end of the transmission pin (24) is fixed on the sliding column (19). When the driving disc (22) is driven by the rotating shaft (11) to rotate on the surface of the mounting disc (18), all the sliding columns (19) are synchronously extended / retracted into the mounting disc (18) through the transmission pin (24).

4. The flameproof multi-degree-of-freedom robotic arm according to claim 3, characterized in that: The end of the rotating shaft (11) has a threaded section, and a locking nut (26) is threadedly matched on the threaded section. The locking nut (26) transmits force by axial elastic extrusion with the driving disc (22) through an elastic gasket.

5. The flameproof multi-degree-of-freedom robotic arm according to claim 3, characterized in that: The portion of the transmission pin (24) located in the arc-shaped hole (23) is rotatably sleeved with a roller (25), and the roller (25) rolls in cooperation with the arc-shaped hole (23).

6. The flameproof multi-degree-of-freedom robotic arm according to claim 3, characterized in that: The end of the transverse finger rod (36) is also connected to a caliper (33), and a friction pad (34) is fixed on the side of the caliper (33) facing the inner side of the mounting plate (18). The caliper (33) can move relative to the transverse finger rod (36).

7. The flameproof multi-degree-of-freedom robotic arm according to claim 6, characterized in that: A rotating column (20) is coaxially rotatably mounted in the horizontal finger rod (36), a threaded column (31) is fixed to one end of the rotating column (20), and a free end of the threaded column (31) is coaxially threadedly mounted in the caliper (33); A crank arm (35) is fixed on the horizontal finger rod (36), and a groove block (32) is fixed at the end of the crank arm (35). The groove block (32) and the caliper (33) are linearly slidably matched, so that when the rotating column (20) rotates, the caliper (33) moves linearly under the restriction of the groove block (32).

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