Wanxiang Group

Abstract

This utility model discloses a universal mechanism configured in a labeling machine, comprising: a swing power component having an output swing member; a flipping frame fixed to the output swing member and having two side plates, wherein at least one side plate is provided with a guide rail; a linear drive unit fixed to the flipping frame and having a push rod; a wheel assembly fixed to the push rod, the provided wheels being guided by the guide rail, and the provided wheel seat having a fork, the fork having an elongated hole or straight groove extending in a predetermined direction; a rotating shaft, the axis of the rotating shaft being perpendicular to the direction of the push rod and the swing axis of the swing member; and a drive arm, the driven end of which is used to install the end component, and the driving end cooperating with the elongated hole or straight groove to form a kinematic pair. The universal mechanism of this utility model has relatively high rigidity, thus easily ensuring the end-effector's position and posture.

Description

Technical Field

[0001] This utility model relates to a universal joint mechanism. Background Technology

[0002] In the field of mechanics, it is often necessary to achieve relatively complex movements, such as the end effector of a multi-degree-of-freedom robotic arm. Its spatial position, initial pose, and target pose are all subject to given requirements. In principle, a multi-degree-of-freedom robotic arm can achieve any possible end effector pose. Besides robotic arms, multi-axis combinations can also achieve poses for things like machining tools, thus enabling the machining of workpieces with complex contours. For example, the commonly used five-axis machine tool achieves control of the machining tool through five-axis coupling (also known as five-axis linkage).

[0003] In mechanical transmission, there is a type of transmission joint called a universal joint, used to realize the transmission of two shafts with a certain included angle. It is achieved by using two rotating shafts with perpendicular axes. The universal mechanism involved in this utility model uses a two-axis linkage to control the end component, and also utilizes a universal joint to propose a novel universal mechanism.

[0004] Most current gimbal mechanisms rely on two rotational motions, with the pose of the end effector determined through their linkage. While their driving methods are diverse and often share some common principles, their implementations differ significantly. Given the cumulative errors that can occur when multi-axis linkages are involved, machine tool technology typically requires the use of sensors such as linear encoders or other detection elements to control the end effector's pose through closed-loop feedback. However, in some implementations, cost and overall computational complexity must be controlled, so sensors like linear encoders are often omitted, and instead, multi-degree-of-freedom algorithmic coupling is used instead.

[0005] The inventors believe that it is necessary to ensure the rigidity of the universal joint in order to guarantee the end-effector's position and orientation.

[0006] It should be noted that the above background technology is technical information that the inventor has acquired in order to deduce the relevant technical problems or obtained in the process of designing this utility model, and does not mean that the above background technology was already prior art before this utility model application, especially the technical content of the cognition and confirmation of the relevant technical problems. Utility Model Content

[0007] This invention provides a universal mechanism with relatively high rigidity, which makes it easy to ensure relatively accurate end-effector posture.

[0008] According to an embodiment of the present invention, a universal joint mechanism is provided, configured in a labeling machine, and the universal joint mechanism includes: The swing power component has an output swing member; A tilting frame, fixed to the output swing member, has two side plates and a connecting plate for fixed connection between the two side plates; wherein at least one side plate is provided with a guide rail; A linear drive unit is fixed on the tilting frame, and the output component is a push rod whose direction is parallel to the guide rail; A wheel assembly is fixed to the push rod, the provided wheel is guided by the guide rail, and the provided wheel seat has a fork with an elongated hole or straight groove extending in a predetermined direction. The rotating shaft is mounted on the side plate via bearings, and the axis of the rotating shaft is perpendicular to the direction of the push rod and the axis of rotation of the swing component. The drive arm is fixed on the rotating shaft to form a lever, and the driven end of the drive arm is used to install the end component, while the driving end cooperates with the elongated hole or straight groove to form a kinematic pair.

[0009] Optionally, the swing power component is a swing cylinder, and the swing stroke is determined based on the stop point control.

[0010] Optionally, the push rod and the wheel assembly are connected by a horizontally placed push plate; In this context, the horizontal direction corresponding to the horizontal position is the axial direction of the rotation axis.

[0011] Optionally, the number of first rollers on each row of rollers is 2 to 4.

[0012] Optionally, if there is only one wheel assembly, the wheel assembly is offset to one side plate; Accordingly, the side plate on which the wheel assembly is biased is the side plate on which the guide rail is mounted.

[0013] Optionally, the drive arm is centrally located between the two side plates and below the linear drive unit.

[0014] Optionally, the shift fork is a vertical plate, and the elongated hole or straight groove extends vertically.

[0015] Optionally, the length of the driven arm of the drive arm is 3 to 6 times the length of the driving arm.

[0016] Optionally, the drive arm is a plate structure, and the corresponding plate surface of the drive arm is perpendicular to the axis of the rotating shaft.

[0017] Optionally, the portion of the drive arm that mates with the elongated hole or straight groove has a second roller.

[0018] According to an embodiment of this utility model, the universal joint mechanism provides a first rotation, specifically a swing rotation, by a swing power component; and a second rotation is provided by a rotating shaft driven by a linear drive unit, with the shaft axis perpendicular to the axis of the first rotation, thus forming a universal joint mechanism. Furthermore, the swing power component is generally a disc-shaped component, directly outputting the first rotation without a transmission component, ensuring high reliability and overall rigidity. The linear drive unit drives a roller assembly via a push rod, guiding it to a guide rail mounted on the side plate. The roller assembly, with its multiple first rollers, provides high stability and relatively high precision, combining the advantages of both rolling and sliding friction. The elongated holes or straight grooves in the roller seats of the roller assembly cooperate with the drive arm mounted on the rotating shaft, driving the drive arm to rotate around the shaft axis, resulting in good overall reliability and easily guaranteed precision. Attached Figure Description

[0019] Figure 1 This is a first schematic diagram of a universal joint mechanism in one embodiment.

[0020] Figure 2 This is a second schematic diagram of the universal joint mechanism in one embodiment.

[0021] Figure 3 This is a schematic diagram of the main frame structure in one embodiment.

[0022] Figure 4 This is a schematic diagram of the linear drive unit and guide slide assembly in one embodiment.

[0023] In the diagram: 1. End component, 2. Drive arm, 3. Bearing, 4. Shaft, 5. Cylinder, 6. Connecting plate, 7. Connecting disc, 8. Pneumatic turntable, 9. Seat plate, 10. Assembly hole, 11. Air pipe connector, 12. Side plate, 13. Guide slide assembly, 14. Shift fork, 15. Second roller, 16. Connecting part, 17. First connecting plate, 18. Guide rail, 19. Cylinder fixing plate, 20. Second connecting plate, 21. Relief groove, 22. U-shaped opening, 23. Wheel arrangement, 24. Wheel arrangement seat, 25. Push plate. Detailed Implementation

[0024] To facilitate understanding of this utility model, the following description, in conjunction with the accompanying drawings and specific embodiments, will provide a more detailed account of the utility model.

[0025] The universal joint mechanism according to the embodiments of this utility model is mainly used in labeling machines. Figure 1 and Figure 2 The end component 1 shown is the part on the labeling machine used to pick up the label. For cotton bales, labels are usually applied to both ends. Currently, the entire cotton processing production line, except for the labeling station at the very end, is almost fully automated.

[0026] For the label, when the label is initially picked up, the label must be in a horizontal position. The front and rear ends of the cotton bale are two parallel vertical surfaces. Therefore, the label needs to be rotated at least 90° after being picked up by the end component 1 in order to be aligned with the front or rear end of the cotton bale.

[0027] Furthermore, given that the front end face is aligned, the rear end face requires the end component 1 to rotate 180°, which also causes the label to become inverted. Therefore, another degree of freedom is needed to ensure the label remains upright on the rear end face of the cotton bale. When this transformation is achieved using a universal joint, the two corresponding rotations only need to be integer multiples of 90° each to ensure the label remains upright whether it is applied to the front or rear end face of the cotton bale. Moreover, mechanical limit switches can be used for position control, eliminating the need for feedback components.

[0028] For ease of explanation, the direction of motion corresponding to the linear motion is defined as the front-back direction, and thus, given that the front-back direction is determined, the left-right direction is also determined. However, it should be noted that in the embodiments of this utility model, terms such as up, down, left, right, inside, outside, front, back, and similar expressions are for illustrative and explanatory purposes only, and are intended to avoid misunderstanding by those skilled in the art. Accordingly, in the embodiments of this utility model, the linear drive unit provides the linear motion, thereby determining the front-back and left-right directions.

[0029] Similarly, statements that are mutually explanatory, such as vertical or horizontal, are also for the purpose of explanation or clarification.

[0030] In addition, in the field of mechanics, it should be known that the front-to-back direction is also called longitudinal, head-to-tail, or length direction, while the left-to-right direction is also called transverse, width direction, or lateral direction.

[0031] In addition, to facilitate the description of the relationship between one component or component and another component or component shown in the accompanying drawings, spatially relative terms such as "lower," "upper," and similar terms may be used in embodiments of this invention. It should be understood that the spatially relative terms are intended to cover different orientations of the device during use and operation, in addition to those depicted in the accompanying drawings.

[0032] Unless otherwise defined, all technical and scientific terms used in this specification have the same meaning as commonly understood by one of ordinary skill in the art to which this invention pertains. The terminology used in the embodiments of this invention is for the purpose of describing particular embodiments only and is not intended to limit the invention.

[0033] Furthermore, as a special note, the technical features involved in the different embodiments of the present invention described below can be combined with each other as long as they do not conflict with each other.

[0034] It should be understood that in the field of mechanics, standard geometric terms are typically used to describe approximate mechanical structures, without implying that the mechanical mechanism possesses the exact geometric features corresponding to those terms. For example, a rectangular plate is actually described as a three-dimensional structure based on the characteristics of a planar figure. In the field of mechanics, using a specific explicit feature of a component to describe it is a common descriptive method, but this does not mean that the component necessarily contains the exact geometric shape corresponding to that explicit feature.

[0035] like Figure 1 and Figure 2 An example of a universal mechanism is used for labeling cotton bales at the front and rear ends. It should be noted that for cotton bales, such as Type I cotton bales that conform to national standards, the length × width × height is 1400 × 530 × 700 mm. The ends usually refer to the two end faces corresponding to the length of the cotton bale.

[0036] Figure 1 and Figure 2 The end component 1 shown has two sets of suction cups. One set of suction cups is used to pick up the first type of label, and the other set of suction cups is used to pick up the second type of label. After picking up one label of each type, for example, the front end of the cotton bag is labeled first, and then one label of each type is picked up before labeling the rear end of the cotton bag.

[0037] As mentioned earlier, since labels are often laid flat when printed or processed and then picked up, this flatness is usually horizontal. Under these conditions, the end component 1 needs to adjust its position after picking up the corresponding label to meet the labeling requirements.

[0038] The universal joint includes a swing power component, which has an output swing member. In some embodiments, the swing power component is a swing cylinder, which can be a swing hydraulic cylinder or a pneumatic turntable 8. Both of these power components can directly output swing.

[0039] It should be noted that in the mechanical field, oscillation usually refers to rotation with a range of less than 360°. For example, oscillating cylinders often use mechanical limits to form a stop point, thereby determining the start and end points of the oscillation stroke. This method does not require the setting of feedback elements, so the working reliability is relatively good.

[0040] The swing cylinder is suitable for heavy-duty applications, while the pneumatic turntable 8 is suitable for relatively light-duty applications that require high response speed. Therefore, in the embodiments of this utility model, the pneumatic turntable 8 is preferably used.

[0041] from Figure 1 and Figure 2As can be seen in the illustrated structure, the pneumatic turntable 8 has a base plate 9 for mounting on, for example, a three-degree-of-freedom conveying mechanism, so as to convey it to the front side of the cotton bale or the rear side of the cotton bale.

[0042] Figure 1 The mounting holes 10 on the center plate 9 are used for mounting the pneumatic turntable 8 on, for example, the aforementioned three-degree-of-freedom conveying mechanism.

[0043] Because it is used to pick up labels that are in a horizontal position, therefore in Figure 1 The illustrated structure shows the universal joint in its label-picking state, with the base plate 9 on top and the end component 1 on the bottom. The connecting plate 7 of the pneumatic turntable 8 is correspondingly on the bottom, and the part that generates another rotation is mounted on the connecting plate 7.

[0044] The two dead points of the pneumatic turntable 8 correspond to two dead point positions, one of which can be used for labeling the front face of the cotton bale, and the other can be used for labeling the rear face of the cotton bale.

[0045] The main body that generates another rotating part is as follows Figure 3 The tilting frame shown is fixedly installed on the connecting plate 7, and the part that mates with the connecting plate 7 is... Figure 1 The connecting plate 6 shown in the figure, the connecting plate 6 in Figure 1 The middle is a horizontal plate, and in Figure 1 It is displayed as a rectangular panel.

[0046] In addition, a disc-shaped component is provided at the center of the connecting plate 6 to facilitate connection with the connecting plate 7. Alternatively, the disc-shaped component can be omitted, and holes corresponding to the connecting holes of the connecting plate 7 can be directly drilled on the connecting plate 6, and then fixed by means of bolt connection, for example.

[0047] Figure 3 In the middle, the connecting plate 6 corresponding to the rectangular plate structure is provided with two side plates 12. The two side plates 12 are parallel to each other and are connected to a pair of opposite sides of the connecting plate 6 by screws. Figure 3 The structure also includes two connecting plates, namely the first connecting plate 17 and the second connecting plate 20 shown in the figure. The two connecting plates are connected to the two side plates 12 to form a rectangular tube structure, and are also connected to the connecting plate 6, thus forming a stable structure with relatively easy overall rigidity.

[0048] Two of the side plates 12 have bearing seat holes, and bearings 3 are installed in the bearing seat holes. A rotating shaft 4 is provided, which is installed in the bearing seat holes through the bearings 3.

[0049] Shaft 4 Figure 3 The center is a horizontal axis, which is perpendicular to the axis of the connecting plate that provides output from the pneumatic mounting plate 3.

[0050] Furthermore, at least one side plate 12 is provided with a guide rail 18, that is, the guide rail 18 has one side guide rail or two side guide rails. Figures 1-3 The illustrated structure shows a single-sided guide rail configuration. Figure 4 As can be seen in the illustrated structure, when using a single-sided guide rail, since the push rod of cylinder 5 is parallel to the guide rail 18, under this condition, the push rod of cylinder 5 will be subjected to a certain radial load in addition to the axial load, which will affect the seal of cylinder 5 and reduce its service life. However, if two-sided guide rails are used, the radial loads generated on both sides are balanced or canceled out, thus allowing the seal of cylinder 5 to have a longer service life. But using a single-sided guide rail can make the overall structure more compact, especially since the cylinder can be offset to one side, making room for the installation of drive arm 2, allowing drive arm 2 to be centered in the left-right direction, making the overall structure easier to arrange.

[0051] Correspondingly, cylinder 5, which constitutes the linear drive unit, is mounted on the tilting frame. Figure 1 In the illustrated structure, the cylinder 5 is mounted on the lower side of the connecting plate 6. In order to adjust the position, a cylinder fixing plate 19 is further provided. Obviously, the cylinder 5 can also be directly fixed on the lower surface of the connecting plate 6. The cylinder fixing plate 19 is mainly used to make the cylinder 5 in a suitable position in the vertical direction to avoid interference in the assembly position, especially to ensure that, for example, the wheel seat 24 and the push plate 25 do not interfere with the connecting plate 6.

[0052] Furthermore, a roller assembly is provided that guides the guide rail 18. The rollers 23 of the roller assembly cooperate with the guide rail 18 to form a guide rail pair. Due to the presence of multiple support points (each first roller provides a fulcrum), the fit gap can be effectively eliminated, thereby ensuring the smoothness of the drive. At the same time, it can make the posture of the end component 1 more stable.

[0053] Each row of rollers uses 2 to 4 first rollers. Figure 4 The illustrated structure uses three first rollers.

[0054] Furthermore, the wheel assembly is fixed to the push rod via its wheel seat 24, and is driven by the push rod to generate linear motion in the direction of the push rod.

[0055] The provided wheel arrangement is guided by the guide rail, and the provided wheel arrangement seat 24 has a fork, the fork having an elongated hole or straight slot extending in a predetermined direction. Figure 4 The illustrated structure uses a straight groove structure, shown as a U-shaped groove in the figure, with the straight groove running vertically.

[0056] Clearly, given a defined extension direction, neither using a straight groove nor an elongated hole affects the fit with the active end of the drive arm 2. Relatively speaking, using a straight groove structure facilitates assembly and disassembly.

[0057] Furthermore, a rotating shaft 4 is provided, which is mounted on the side plate 12 via a bearing 3. Figure 1 In the illustrated structure, this is represented as a horizontal axis. Accordingly, the axis of this rotating shaft 3 is perpendicular to the direction of the push rod and the axis of rotation of the swinging member.

[0058] The drive arm 2 is fixedly mounted on the rotating shaft 3 to form a lever, thus having an active end and a driven end. The driven end of the drive arm 2 is used to install the end component 1, while the active end cooperates with the elongated hole or straight groove to form a kinematic pair.

[0059] exist Figure 2 In the illustrated structure, a second roller 15 is mounted on the driving end of the drive arm 2. This second roller 15 runs through the elongated hole or straight groove. When the shift fork 4 moves horizontally, the driving end of the drive arm 2 can convert the horizontal movement of the shift fork 4 into rotation of the drive arm 2. The driving end of the drive arm 2 has horizontal and vertical components. The second roller 15 is mainly used to convert sliding friction into rolling friction. Obviously, the desired motion can still be achieved using only sliding friction; the difference lies only in the magnitude of the coefficient of friction.

[0060] The two side plates 12 mentioned above define the left and right directions, which, as previously stated, are also commonly referred to as the lateral direction. Figure 4 In the illustrated structure, cylinder 5 is arranged parallel to guide rail 18, and the wheel assembly running on guide rail 18 is horizontally connected to the push rod of cylinder 5. Specifically... Figure 4 The wheel seat 24 of the middle wheel assembly is horizontally connected to the push rod via the push plate 25. This structure is relatively compact and can make full use of the lateral space.

[0061] Regarding the number of wheel assemblies, as mentioned earlier, in some embodiments, a single wheel assembly is used, which is then offset, in which case the cylinder 5 is also offset on the main frame. Correspondingly, the drive arm 2 is centrally located between the two side plates 12 and below the linear drive unit.

[0062] exist Figure 4 In the illustrated structure, the fork is a vertical plate, and the elongated hole or straight groove extends vertically. This structure has relatively good reliability and relatively high static stiffness.

[0063] In addition, Figure 2As can be seen in the illustrated structure, the length of the driven arm of the driving arm 2 is much greater than the length of its driving arm, and the length ratio between the two is preferably 3 to 6, with 4.5 used in the preferred embodiment.

[0064] In order to have a relatively greater load-bearing capacity under the condition of comparable weight, the drive arm 2 is a plate structure, and the corresponding plate surface of the drive arm 2 is perpendicular to the axis of the rotating shaft 4.

[0065] The connection between the drive arm 2 and the rotating shaft 4 is a typical structure of shaft connection. It is only necessary to determine the installation position of the drive arm 2 on the rotating shaft 4, and the connection method is obvious.

[0066] The above description is illustrative in conjunction with the accompanying drawings and is not intended to limit the scope of this utility model. Within the concept of this utility model, the above embodiments or different embodiments can be combined without conflict. Although the utility model has been described in detail in the foregoing embodiments, those skilled in the art should understand that modifications can still be made to the foregoing embodiments, or equivalent substitutions can be made to some of the technical features. These modifications or substitutions do not cause the corresponding technical solutions to deviate from the scope of the technical solutions of the embodiments of this utility model.

Claims

1. A universal joint mechanism, configured in a labeling machine, characterized in that, include: The swing power component has an output swing member; A tilting frame, fixed to the output swing member, has two side plates and a connecting plate for fixed connection between the two side plates; wherein at least one side plate is provided with a guide rail; A linear drive unit is fixed on the tilting frame, and the output component is a push rod whose direction is parallel to the guide rail; A wheel assembly is fixed to the push rod, the provided wheel is guided by the guide rail, and the provided wheel seat has a fork with an elongated hole or straight groove extending in a predetermined direction. The rotating shaft is mounted on the side plate via bearings, and the axis of the rotating shaft is perpendicular to the direction of the push rod and the axis of rotation of the swing component. The drive arm is fixed on the rotating shaft to form a lever, and the driven end of the drive arm is used to install the end component, while the driving end cooperates with the elongated hole or straight groove to form a kinematic pair.

2. The universal joint mechanism according to claim 1, characterized in that, The swing power component is a swing cylinder, and the swing stroke is determined based on the stop point control.

3. The universal joint mechanism according to claim 1, characterized in that, The push rod and the wheel assembly are connected by a horizontally placed push plate; In this context, the horizontal direction corresponding to the horizontal position is the axial direction of the rotation axis.

4. The universal joint mechanism according to claim 1, characterized in that, The number of first rollers on each row of rollers is 2 to 4.

5. The universal joint mechanism according to claim 1 or 4, characterized in that, If there is only one wheel assembly, the wheel assembly is offset to one side plate; Accordingly, the side plate on which the wheel assembly is biased is the side plate on which the guide rail is mounted.

6. The universal joint mechanism according to claim 5, characterized in that, The drive arm is centrally located between the two side plates and below the linear drive unit.

7. The universal joint mechanism according to claim 6, characterized in that, The fork is a vertical plate, and the elongated hole or straight groove extends vertically.

8. The universal joint mechanism according to claim 7, characterized in that, The length of the driven arm of the drive arm is 3 to 6 times the length of the driving arm.

9. The universal joint mechanism according to claim 1, characterized in that, The drive arm has a plate structure, and the corresponding plate surface of the drive arm is perpendicular to the axis of the rotating shaft.

10. The universal joint mechanism according to claim 1 or 9, characterized in that, The portion of the drive arm that mates with the elongated hole or straight groove has a second roller.

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