Guard structure and horizontal multi-joint robot

Abstract

This invention relates to the field of robotics, specifically to a protective shield structure and a horizontal multi-joint robot. The protective shield structure includes a ball spline screw that moves along a predetermined axial direction; a long shaft, the lower end of which is fixed to the ball spline screw; a rotating bushing that is rotatably fixed inside a bearing mounting sleeve; a spring, one end of which is fixed to the outside of the long shaft and the other end of which is fixed to the outside of the rotating bushing, which moves upward or downward along the axial direction when the long shaft moves; and a protective shield, the fixed end of which is mounted on a housing and the movable end of which is mounted on the bearing mounting sleeve. The protective shield and the bearing mounting sleeve extend and retract along the axial direction following the rotating bearing. The protective shield structure of this invention can increase the robot's stroke without increasing its overall dimensions.

Description

Technical Field

[0001] This invention relates to the field of robotic equipment technology, specifically to a protective shield structure and a horizontal multi-joint robot. Background Technology

[0002] Horizontal articulated robots are characterized by high speed and high precision. In some high-protection scenarios, adding a protective cover to the ball spline screw can effectively prevent large amounts of dust and moisture generated in the working environment from entering the robot and affecting its normal operation. Additionally, adding a protective cover is also a solution to improve the robot's cleanliness level and can be applied in scenarios with strict cleanliness requirements.

[0003] Prior art patent literature:

[0004] Patent Document 1: Japanese Patent Application Publication No. 2012-228733

[0005] Patent Document 2: Application No. 202280021286.4, Linear Mechanism and Horizontal Multi-Joint Robot

[0006] Patent document 1 provides a solution to add a protective cover to the lead screw, thereby increasing the stroke by adding a relay shaft. However, since the protective cover is composed of pleated parts, its compressed size is limited, which will sacrifice the robot's stroke.

[0007] Patent document 2 improves the stroke by incorporating a protective cover without adding a relay axis, but the protective cover being directly fixed to the robot results in a larger outer volume of the robot, which is not conducive to use in confined spaces.

[0008] Therefore, there is a need to find new technical solutions that can increase the protective cover while keeping the overall size unchanged and without affecting the robot's travel. Summary of the Invention

[0009] To address the aforementioned technical problems, this invention proposes a protective shield structure and a horizontal multi-joint robot.

[0010] The technical problem to be solved by this invention is achieved by the following technical solution:

[0011] A protective shield structure, comprising:

[0012] A ball spline screw is installed inside a housing and moves along a predetermined axial direction. A spline nut is provided at its lower end.

[0013] A protective cover has a fixed end mounted on a housing and a bearing mounting sleeve mounted on its movable end. The protective cover and the bearing mounting sleeve can extend and retract along the axial direction.

[0014] A rotating bushing is rotatably fixed inside the bearing mounting sleeve, and a guide groove for linear motion is provided inside the rotating bushing.

[0015] A long shaft, the lower end of which is fixed to the upper end face of the ball spline screw, and the upper end of which is movably disposed in the rotating bushing. A guide bar is provided on the long shaft and installed in the guide groove.

[0016] A spring, one end of which is fixed to the outer end face of the long shaft and the other end of which is fixed to the outer end face of the rotating bushing, when the long shaft moves upward or downward along the axial direction, the spring is compressed or stretched, causing the rotating bushing and the protective cover to move upward or downward along the axial direction.

[0017] When the protective cover is stretched to its upper limit size, the guide bar of the long shaft is fully inserted into the rotating bushing, and the end face of the guide bar of the long shaft contacts the rotating bushing. When the protective cover is compressed to its lower limit size, the long shaft contacts the spline nut of the ball spline screw.

[0018] As a further improvement to the above technical solution, a sealing ring is provided between the guide strip of the long shaft and the guide groove of the rotating bushing. The inner ring of the sealing ring is fixed on the guide strip of the long shaft, and the outer ring of the sealing ring can move within the guide groove of the rotating bushing.

[0019] As a further improvement to the above technical solution, a fixing hole is arranged on the lower circumferential side of the long shaft, and the long shaft is fixed to the upper end face of the ball spline screw through the fixing hole.

[0020] As a further improvement to the above technical solution, a bearing is installed between the rotating bushing and the bearing mounting sleeve, and an oil seal is installed on the outside of the bearing.

[0021] As a further improvement to the above technical solution, a shaft retaining ring is installed on the rotating bushing to limit the lower end face of the bearing, and a hole retaining ring is installed on the bearing mounting sleeve to limit the upper end face of the bearing.

[0022] As a further improvement to the above technical solution, the materials of the long shaft, the rotating bushing, and the bearing mounting sleeve are stainless steel.

[0023] As a further improvement to the above technical solution, a first clamp and a first sealing gasket are installed between the fixed end of the protective cover and the shell.

[0024] As a further improvement to the above technical solution, a second clamp and a second sealing gasket are installed between the movable end of the protective cover and the bearing mounting sleeve.

[0025] A horizontal multi-joint robot, the robot having a protective shield structure as described in any one of claims 1-8.

[0026] The beneficial effects of this invention are:

[0027] The present invention provides a protective shield structure and a horizontal multi-joint robot, wherein the protective shield structure can increase the robot's stroke without increasing its external dimensions. Attached Figure Description

[0028] The present invention will be further described below with reference to the accompanying drawings and embodiments:

[0029] Figure 1 This is a schematic diagram of the overall structure of the horizontal multi-joint of the present invention;

[0030] Figure 2 This is a cross-sectional view of the overall structure of the protective cover of the present invention;

[0031] Figure 3 This is a partial cross-sectional view of the protective shield structure of the present invention when it is at the upper limit of the stroke.

[0032] Figure 4 This is a partial cross-sectional view of the protective cover being compressed to its limit size during downward movement of the present invention.

[0033] Figure 5 This is a partial cross-sectional view of the spring of the present invention being stretched to its limit size when it is at the lower limit of its stroke.

[0034] Figure 6 This is a three-dimensional structural schematic diagram of the rotating bushing of the present invention;

[0035] Figure 7 This is a three-dimensional structural diagram of the long axis of the present invention.

[0036] In the diagram: 1. Horizontal multi-joint robot; 2. Base; 3. Bellows; 4. First arm; 5. Second arm; 51. First pulley; 52. First synchronous belt; 53. Second synchronous belt; 54. Second pulley; 55. Mounting plate; 6. Housing; 7. Protective cover structure; 71. Ball spline screw; 711. Screw nut; 712. Spline nut; 72. Long shaft; 721. Sealing ring; 722. Guide bar; 723. Guide bar end face; 724. Fixing hole; 73. Spring; 74. Rotating bushing; 741. Guide groove; 742. Shaft retaining ring; 75. Hole retaining ring; 76. Bearing mounting sleeve; 77. Oil seal; 78. Bearing; 79. Protective cover; 791a. First clamp; 791b. Second clamp; 792a. First sealing gasket; 792b. Second sealing gasket. Detailed Implementation

[0037] To make the technical means, creative features, objectives and effects of this invention easier to understand, the invention will be further described below in conjunction with the accompanying drawings and embodiments.

[0038] like Figure 1 and Figure 3 As shown, the horizontal multi-joint robot 1 of this embodiment includes, for example, a base 2, a first arm 4 mounted on the base 2, and a second arm 5 mounted on the first arm 4. The first arm 4 is mounted on the base 2 in a manner that allows it to rotate about a first axis A extending in the vertical direction. The second arm 5 is mounted on the first arm 4 in a manner that allows it to rotate about a second axis B parallel to the first axis A. A housing 6 covering the upper part of the second arm 5 is mounted on the second arm 5. Inside the housing 6, a drive component (not shown) for driving a ball spline screw 71 is arranged. The drive includes a first pulley 51, a first synchronous belt 52, a second synchronous belt 53, a second pulley 54, and a mounting plate 55, which is connected to the inside of the housing 6. The first pulley 51, the first synchronous belt 52, the second synchronous belt 53, and the second pulley 54 move. A bellows 3 provided on the base 2 and the housing 6 provides power to the drive component inside the housing 6.

[0039] Furthermore, the horizontal articulated robot 1 of this embodiment includes a protective shield structure 7 mounted on the second arm 5. For example... Figures 2 to 3 As shown, the protective cover structure 7 includes: a ball spline screw 71 installed inside the housing 6; the ball spline screw 71 extends along a third axis C in the vertical direction through the second arm 5 and the housing 6; the first pulley 51 drives the screw nut 711 to force the ball spline screw 71 to move vertically up and down along the third axis C; and the second pulley 54 drives the spline nut 712 to force the ball spline screw 71 to rotate around the third axis C.

[0040] like Figure 2As shown, a long shaft 72 is mounted on the upper end face of the ball spline screw 71. A fixing hole 724 is arranged on the lower circumferential side of the long shaft 72. The long shaft 72 is fixed to the upper end face of the ball spline screw 71 through the fixing hole 724 and moves linearly along the third axis C and rotates around the third axis C along with the ball spline screw 71. The long shaft 72 can be a solid shaft or a hollow shaft. A bearing 78 is installed between the rotating bushing 74 and the bearing mounting sleeve 76. The rotating bushing 74 can rotate relative to the bearing mounting sleeve 76 along the third axis C. The bearing 78 is axially limited by a retaining ring 75 for the bore and a retaining ring 742 for the shaft. An oil seal 77 is installed on the outside of the bearing 78.

[0041] A spring 73 is installed between the long shaft 72 and the rotating sleeve 74. The two ends of the spring 73 are fixed on the long shaft 72 and the rotating sleeve 74 respectively. The spring 73 compresses or stretches as the long shaft 72 moves, causing the rotating sleeve 74 and the protective cover 79 to move upward or downward along the third axis C.

[0042] The fixed end of the protective cover 79 is mounted on the housing 6, and the movable end of the protective cover 79 is mounted on the bearing mounting sleeve 76. A first clamp 791a and a first sealing gasket 792a are provided at the fixed point between the protective cover 79 and the housing 6. The movable end of the protective cover 79 is fixed to the outside of the bearing mounting sleeve 76, and a second clamp 791b and a second sealing gasket 792b are provided between them. The clamps serve a fixing function, and the sealing gaskets serve a sealing function.

[0043] like Figure 3 , Figure 6 and Figure 7 As shown, a guide bar 722 is provided on the long shaft 72. The guide bar 722 is installed in the guide groove 741 inside the rotating bushing 74. The guide bar 722 can move up and down in the guide groove 741. The guide bar 722 on the long shaft 72 can transmit torque to the guide groove 741 to drive the rotating bushing 74 to rotate. A sealing ring 721 is provided between the guide bar 722 of the long shaft 72 and the guide groove 741 of the rotating bushing 74. The inner ring of the sealing ring 721 is fixed on the guide bar 722 of the long shaft 72, and the outer ring of the sealing ring 721 can move in the guide groove 741 of the rotating bushing 74.

[0044] like Figure 3 As shown, when the ball spline screw 71 moves upward, the spring 73 is compressed and pushes the rotating bushing 74 and the protective cover 79 upward. The guide bar 722 on the long shaft 72 moves along the guide groove 741 of the rotating bushing 74. When the guide bar 722 is fully inserted into the guide groove 741, the end face 723 of the guide bar of the long shaft 72 contacts the rotating bushing 74, the ball spline screw 71 reaches the positive limit, the spring 73 is compressed to the limit size, and the protective cover 79 is stretched to the limit size.

[0045] like Figure 4 and Figure 5 As shown, when the ball spline screw 71 moves downward, the spring 73 is pulled and drives the rotating bushing 74 and the protective cover 79 to move downward. When the protective cover 79 is compressed to its limit size during the downward movement, the rotating bushing 74 cannot continue to move downward due to the support force of the protective cover 79. When the ball spline screw 71 continues to move downward, the spring 73 is stretched and drives the guide bar 722 of the long shaft 72 to start moving downward along the guide groove 741. The protective cover 79 remains stationary. When the long shaft 72 contacts the spline nut 712, the ball spline screw 71 moves to the lower limit.

[0046] The functions of the protective cover structure 7 and the horizontal multi-joint robot 1 of the present invention will be explained below.

[0047] According to an embodiment of the present invention, the base 2 of the horizontal multi-joint robot 1 can be fixed on the ground or a platform. The first arm 4, which rotates about the first axis A, and the second arm 5, which rotates about the second axis B, can position the ball spline screw 71 at the end to the desired position. The bellows 3 installed on the base 2 and the housing 6 provide power to the servo motor in the housing 6.

[0048] The housing 6 contains two servo motors. The first servo motor can drive the first synchronous belt 52 to rotate the first pulley 51, thereby enabling the ball spline screw 71 to move linearly along the third axis C. The second servo motor can drive the second synchronous belt 53 to rotate the second pulley 54, thereby enabling the ball spline screw 71 to rotate along the third axis C.

[0049] For example, such as Figure 3As shown, a long shaft 72 is installed at the upper end of the ball spline screw 71. The actual travel length of the guide bar 722 of the long shaft 72 in the guide groove 741 of the rotating sleeve 74 is the additional travel that the protective cover structure 7 can achieve based on current technology. A spring 73 is fixed between the long shaft 72 and the rotating sleeve 74. The elastic force of the spring 73 can drive the rotating sleeve 74 to move downward when the long shaft 72 moves downward. The guide bar 722 of the long shaft 72 and the guide groove 741 of the rotating sleeve 74 have a rectangular structure, which can facilitate the transmission of torque when the long shaft 72 is rotated by the ball spline screw 71, driving the rotating sleeve 74 to rotate around the third axis C. The sealing ring 721 on the long shaft 72 ensures the seal between the long shaft 72 and the rotating sleeve 74 during movement. A bearing 78 is installed between the rotating sleeve 74 and the bearing mounting sleeve 76. When the rotating sleeve 74 rotates, it can ensure that the bearing mounting sleeve 76 is not affected by rotation, avoiding damage to the protective cover 79 fixed on the outside due to rotational force. The bearing 78 is axially positioned by the retaining ring 75 and the shaft retaining ring 742 installed on the rotating bushing 74 and the bearing mounting sleeve. An oil seal 77 is installed on the outside of the bearing 78 to seal it and prevent external dust from entering or internal gas from escaping during the movement of the protective cover 79.

[0050] During the downward movement of the ball spline screw 71, according to the existing technology, when the protective cover 79 is compressed to its limit size, the ball spline screw 71 reaches its lower limit position. This technical solution sacrifices stroke. Therefore, in the technical solution of this embodiment, when the protective cover 79 is compressed to its limit size, the ball spline screw 71 can continue to move downward to expand the stroke. At this time, the spring 73 installed on the long shaft 72 is stretched, which drives the guide bar 722 to move downward along the guide groove 741 until the long shaft 72 contacts the spline nut 712. The ball spline screw 71 can reach the stroke without adding the protective cover 79. Therefore, when adding the protective cover 79, the stroke of the ball spline screw 71 can be preserved. At the same time, the long shaft 72, the rotating bushing 74, and the bearing mounting sleeve 76 are all made of stainless steel, which can meet the requirements of food industry applications.

[0051] The foregoing has shown and described the basic principles, main features, and advantages of the present invention. Those skilled in the art should understand that the present invention is not limited to the above embodiments. The embodiments and descriptions in the specification are merely prisms of the invention. Various changes and modifications can be made to the invention without departing from its spirit and scope, and all such changes and modifications fall within the scope of the present invention as claimed. The scope of protection of this invention is defined by the appended claims and their equivalents.

Claims

1. A guard structure, characterized by: include: A ball spline screw (71) is installed inside the housing (6) and moves along a predetermined axial direction. A spline nut (712) is provided at its lower end. The protective cover (79) has its fixed end installed on the housing (6) and its movable end is equipped with a bearing mounting sleeve (76). The protective cover (79) and the bearing mounting sleeve (76) move in a telescopic motion along the axial direction. The rotating bushing (74) is rotatably fixed in the bearing mounting sleeve (76), and a guide groove (741) for linear motion is provided in the rotating bushing (74); The long shaft (72) has its lower end fixed on the upper end face of the ball spline screw (71) and its upper end is movably disposed in the rotating bushing (74). The long shaft (72) is provided with a guide strip (722) installed in the guide groove (741). A spring (73) has one end fixed to the outer end face of the long shaft (72) and the other end fixed to the outer end face of the rotating bushing (74). When the long shaft (72) moves upward or downward along the axial direction, the spring (73) is compressed or stretched, causing the rotating bushing (74) and the protective cover (79) to move upward or downward along the axial direction. When the protective cover (79) is stretched to its upper limit size, the guide bar (722) of the long shaft (72) is fully inserted into the rotating bushing (74), and the end face (723) of the guide bar of the long shaft (72) contacts the rotating bushing (74). When the protective cover (79) is compressed to its lower limit size, the long shaft (72) contacts the spline nut (712) of the ball spline screw (71).

2. A shield structure according to claim 1, wherein: A sealing ring (721) is provided between the guide bar (722) of the long shaft (72) and the guide groove (741) of the rotating bushing (74). The inner ring of the sealing ring (721) is fixed on the guide bar (722) of the long shaft (72), and the outer ring of the sealing ring (721) can move within the guide groove (741) of the rotating bushing (74).

3. A shield structure according to claim 1, wherein: A fixing hole (724) is arranged on the lower circumferential side of the long shaft (72), and the long shaft (72) is fixed to the upper end face of the ball spline screw (71) through the fixing hole (724).

4. The shield structure of claim 1, wherein: A bearing (78) is installed between the rotating bushing (74) and the bearing mounting sleeve (76), and an oil seal (77) is installed on the outside of the bearing (78).

5. A shield structure according to claim 4, wherein: The rotating bushing (74) is equipped with a shaft retaining ring (742) that limits the lower end face of the bearing (78), and the bearing mounting sleeve (76) is equipped with a hole retaining ring (75) that limits the upper end face of the bearing (78).

6. A shield structure according to claim 1, wherein: The long shaft (72), the rotating bushing (74), and the bearing mounting sleeve (76) are made of stainless steel.

7. The shield structure of claim 1, wherein: A first clamp (791a) and a first sealing gasket (792a) are installed between the fixed end of the protective cover (79) and the housing (6).

8. The shield structure of claim 1, wherein: A second clamp (791b) and a second sealing gasket (792b) are installed between the movable end of the protective cover (79) and the bearing mounting sleeve (76).

9. A horizontal multi-joint robot, characterized by: The robot has the protective shield structure as described in any one of claims 1-8.

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