Patent Application
20210046595
This application claims priority to Chinese Patent Application No. 201810448274.5 entitled “OVERHEAD MACHINING DEVICE BASED ON PORTABLE FIVE-DEGREE-OF-FREEDOM FULL PARALLEL MODULE”, filed by TSINGHUA UNIVERSITY on May 11, 2018.
The present invention relates to the field of computer numerical control (CNC) manufacturing technologies, and in particular to an overhead machining device based on a portable five-degree-of-freedom (5-DOF) full parallel module.
Recently, the mechanical design level is increasingly developing in the field of mechanical design and manufacture. The complex shapes such as spatial curved surfaces and irregular shaped holes usually appear in components. This has led to stricter requirements on manufacturing devices and machining techniques. To achieve the machining of such complex components, the manufacturing device should have the five-axis machining ability. In order to reduce the workpiece mounting times, improve the machining precision and the machining efficiency, the machining devices are required to have higher machining and rotating flexibility and to have ability to achieve five-face machining in one setup.
A parallel kinematic mechanism is a closed-loop parallel mechanism whose mobile platform and frame are connected by multiple chains. Compared with the traditional serial kinematic mechanism, the parallel kinematic mechanism has the advantages of compact structure, high rigidity, strong bearing capability, high response speed, absence of geometric error accumulation and amplification effect. Therefore, the parallel kinematic mechanism has become an ideal choice of the portable machining module. Because the lower-mobility parallel kinematic mechanisms (the DOF of which is less than six) are easier to have a large workspace, especially a rotation workspace, such mechanisms are widely researched. The 5-DOF full parallel mechanism can achieve flexible five-axis motion, so it is utilized as the portable machining module here. However, compared with the serial kinematic mechanism, the parallel kinematic mechanism still has the defects of short movement stroke and small workspace. Therefore, it is also hard to achieve the machining of large and complex components. In order to solve the problem, a feasible way is to combine a parallel machining module with a CNC rotary table and a sliding table. The advantages of the parallel kinematic mechanism are fully exerted. The novel machining device can ensure high rigidity, strong bearing capability, large swing angle range, and five-axis machining ability and expands the movement stroke and the machining range.
With the rapid development of the mechanical design and manufacture industry, demands on the complex components are increased day by day. However, the traditional machine tool generally utilizes a machining manner of firstly mounting the workpieces and then machining them at the same position, this inevitably causes the stop of the machine tool during mounting. Therefore, the usage rate of the machine tool and the yield of the components are reduced, which is urgent to be solved.
The present invention seeks to solve the problems existing in the related art to at least some extent.
Accordingly, an objective of the present invention is to provide an overhead machining device based on a portable 5-DOF full parallel module, which may achieve the machining of large and complex components, simultaneously conducts the mounting and the machining of workpieces at different stations, and improves the usage rate and the production efficiency of a portable parallel module.
In order to achieve the above objective, an embodiment of the present invention provides an overhead machining device based on a portable 5-DOF full parallel module.
Using the portable 5-DOF full parallel module, the overhead machining device based on a portable 5-DOF full parallel module of the embodiment of the present invention can achieve the machining of the large and complex components, conduct the mounting and the machining of the workpieces at the different stations simultaneously, and improve the usage rate and the production efficiency of the portable parallel module.
Additionally, the overhead machining device based on a portable 5-DOF full parallel module according to the embodiment of the present invention may further have the following additional technical characteristics:
Further, in one embodiment of the present invention, the portable 5-DOF full parallel module comprises a portable frame, a spindle, and the first chain to the fifth chain for connecting the portable frame with the spindle to achieve five-axis motion.
Further, in one embodiment of the present invention, to the first chain, the first chain is connected with the portable frame through two mutually vertical first revolute joints and is also connected with the spindle through one second revolute joint. The first chain comprises an input-driven first screw-nut pair to achieve a rotational DOF of a screw around the nut axis and a translational DOF along the chain. For the second to the fifth chains, each chain is connected with the portable frame through two mutually vertical third revolute joints and is also connected with the spindle through two mutually vertical fourth revolute joints. Each chain comprises an input-driven second screw-nut pair to achieve the rotational DOF around the nut axis and the translational DOF along the chain.
Further, in one embodiment of the present invention, the first chain comprises the first motor. One end of the first motor is connected with the portable frame through two mutually vertical revolute joints.
Further, in one embodiment of the present invention, to the first screw-nut pair, the nut of the first screw-nut pair is fixedly connected with the first motor to form a cylindrical kinematic pair so as to achieve the rotational DOF around the nut axis and the translational DOF along the chain. The screw of the first screw-nut pair is connected with the spindle through a revolute joint.
Further, in one embodiment of the present invention, each chain in the range of the second chain and the fifth chain comprises a motor, specifically the second motor, the third motor, the fourth motor and the fifth motor. One end of each motor is connected with the portable frame through two mutually vertical revolute joints.
Further, in one embodiment of the present invention, each chain in the range of the second chain and the fifth chain comprises a screw-nut pair, specifically the second screw-nut pair, the third screw-nut pair, the fourth screw-nut pair and the fifth screw-nut pair. The nut of each screw-nut pair is fixedly connected with the second motor to form a cylindrical kinematic pair so as to achieve the rotational DOF of a screw around the nut axis and the translational DOF along the chain. The screw of each screw-nut pair is connected with the spindle through two mutually vertical revolute joints of a Hooke's joint.
Further, in one embodiment of the present invention, a swing angle range of the portable 5-DOF full parallel module meets the preset conditions to achieve the conversion between vertical and horizontal machining modes.
Further, in one embodiment of the present invention, after the machining of a component is completed, the portable parallel module can move to the position of a mounted component through a sliding table or in a hoisting manner to conduct the machining of the next component. Thus, the mounting and the machining of the workpieces are simultaneously conducted at different stations, and the usage rate and the production efficiency of the portable parallel module are improved.
Further, in one embodiment of the present invention, the portable 5-DOF full parallel module is driven hydraulically or by an electric cylinder or an air cylinder.
These and other aspects and advantages of embodiments of the present invention will become apparent and more readily appreciated from the following descriptions made with reference to the accompanying drawings, in which:
Embodiments of the present invention are described below in detail. Examples of the embodiments are shown in the accompanying drawings. The same or similar reference signs represent the same or similar elements or elements having the same or similar functions throughout the specification. The embodiments described below with reference to the accompanying drawings are exemplary, and are only used to explain the present invention but should not be construed as a limitation to the present invention.
The following describes an overhead machining device based on a portable 5-DOF full parallel module proposed according to an embodiment of the present invention with reference to the accompanying drawings.
As shown in
Further, as shown in
Wherein the CNC rotary table II is mounted on the T-shaped slot platform 13 and is used for mounting the components to be machined. In combination with the portable 5-DOF parallel module III, the CNC rotary table can achieve five-face machining while once mounting.
As shown in
Wherein the first chain 31 is connected with the portable frame 36 through two mutually vertical revolute joints and is also connected with the spindle 37 through a revolute joint. The first chain 31 comprises an input-driven screw-nut pair. The second chain 32 is connected with the portable frame 36 through two mutually vertical revolute joints and is also connected with the spindle 37 through two mutually vertical revolute joints. The second chain 32 comprises an input-driven screw-nut pair. The structures of the third chain 33, the fourth chain 34 and the fifth chain 35 are the same as the structure of the second chain 32. Wherein the five chains are respectively connected between the portable frame 36 and the spindle 37 to form a closed-loop parallel structure, thus achieving three rotational DOF and two translational DOF of the spindle 37.
Further, in one embodiment of the present invention, the first chain 31 comprises the first motor. One end of the first motor is connected with the portable frame 36 through a Hooke's joint or a universal joint or two mutually vertical revolute joints. A nut of the first screw-nut pair is fixedly connected with the first motor to form a cylindrical kinematic pair so as to achieve the rotational DOF of a screw around the nut axis and the translational DOF along the chain. The screw of the first screw-nut pair is connected with the spindle 37 through a revolute joint.
Further, as shown in
In another embodiment of the present invention, the first chain 31 may further comprise: the first motor. One end of the first motor is connected with the portable frame 36 through a spherical joint or three mutually vertical revolute pairs. The nut of the first screw-nut pair is fixedly connected with the first motor. The rotational DOF around the nut axis is locked by a groove to form a translational joint so as to achieve the translational DOF along the chain. The screw of the first screw-nut pair is connected with the spindle 37 through a revolute pair.
In one embodiment of the present invention, each of the second chain 32, the third chain 33, the fourth chain 34 and the fifth chain 35 comprises the second motor. One end of the second motor is connected with the portable frame 36 through a Hooke's joint or a universal joint or two mutually vertical revolute joints. A nut of the second screw-nut pair is fixedly connected with the second motor to form a cylindrical kinematic pair so as to achieve the rotational DOF of a screw around the nut axis and the translational DOF along the chain. The screw of the second screw-nut pair is connected with the spindle 37 through a Hooke's joint or a universal joint or two mutually vertical revolute joints.
Further, as shown in
In another embodiment of the present invention, each of the second chain 32, the third chain 33, the fourth chain 34 and the fifth chain 35 comprises the second motor. One end of the second motor is connected with the portable frame 36 through a spherical joint or three mutually vertical revolute joints. The nut of the second screw-nut pair is fixedly connected with the second motor. The rotational DOF around the nut axis is locked by a groove to form a translational joint so as to achieve the translational DOF along the chain. The screw of the second screw-nut pair is connected with the spindle 37 through a Hooke's joint or a universal joint or two mutually vertical revolute joints.
Further, in one embodiment of the present invention, the portable 5-DOF parallel module III is mounted on the sliding table I such that it can increase the movement stroke of the machine tool and achieve the machining of the large and complex components.
Further, in one embodiment of the present invention, after the machining of the workpieces is completed, the portable 5-DOF parallel module III can move to the position of a mounted component in a hoisting manner to conduct the machining of the next workpiece. Thus, the mounting and the machining of the workpieces are simultaneously conducted, the mounting time of the workpieces is saved, and the usage rate of the portable 5-DOF parallel module is improved.
In one embodiment of the present invention,
The parallel module of the overhead machining device based on a portable 5-DOF full parallel module in the embodiments of the present invention is flexible to move. After the parallel module is mounted on the sliding table, its stroke can be increased. Using the parallel module, the machining of the large and complex components can be achieved, the mounting and the machining of the workpieces can be simultaneously conducted at different stations, and the usage rate and the production efficiency of the portable parallel module are improved.
In the description of the present invention, it should be understood that orientations or position relationships indicated by terms “center”, “longitudinal”, “transverse”, “length”, “width”, “thickness”, “upper”, “lower”, “front”, “back”, “left”, “right”, “vertical”, “horizontal”, “top”, “bottom”, “inside”, “outside”, “clockwise”, “counterclockwise”, “axial”, “radial”, “circumferential”, etc. are orientations or position relationships as shown in the accompanying drawings, and these terms are just used to facilitate description of the present invention and simplify the description, but not to indicate or imply that the mentioned apparatus or elements must have a specific orientation and must be established and operated in a specific orientation, and thus, these terms cannot be understood as a limitation to the present invention.
Moreover, the terms such as “first”, “second”, and the like described in the present invention are used herein only for the purpose of description and are not intended to indicate or imply relative importance, or implicitly indicate the number of the indicated technical features. Therefore, features defined by “first” and “second” may explicitly or implicitly include at least one of the features. In description of the present invention, “a plurality of” means at least two, for example, two or three, unless otherwise clearly and specifically limited.
In the present invention, unless otherwise clearly specified and limited, meanings of terms “installation”, “connected”, “connection”, “fixing”, and the like should be understood in a board sense. For example, “connection” may be a fixed connection, a removable connection, or integration; may be a mechanical connection or an electrical connection; may be a direct connection or an indirect connection implemented by using an intermediate medium; or may be intercommunication between two components or an interaction relationship between two components, unless otherwise clearly limited. A person of ordinary skill in the art may understand specific meanings of the foregoing terms in the present invention based on a specific situation.
In the present invention, unless otherwise clearly specified and limited, the first feature being “above” or “below” the second feature may include the first feature and the second feature being in direct contact, or may also include the first feature and the second feature being in indirect contact via an intermediate medium. Further, the first feature being “over”, “above” or “on the top of” the second feature may include the first feature being directly above or obliquely above the second feature, or merely indicates the horizontal height of the first feature being greater than that of the second feature. The first feature being “under”, “below” or “underneath” the second feature may include the first feature being directly below or obliquely below the second feature, or merely indicates the horizontal height of the first feature being less than that of the second feature.
Reference to phrases such as “an embodiment”, “some embodiments”, “an example”, “a specific example”, and “some examples” in the specification mean that specific features, structures, materials or characteristics described in combination with the embodiment(s) or example(s) are included in at least one embodiment or example of the present invention. In the specification, the schematic expressions of the phrases do not necessarily refer to the same embodiment or example. Moreover, the described specific features, structures, materials or characteristics may be combined in any suitable manner in one or more embodiments or examples. Additionally, in a non-conflicting situation, those skilled in the art may joint and combine different embodiments or examples and features of different embodiments or examples described in the specification.
Although the embodiments of the present invention have been illustrated and described, it should be understood that the above embodiments are exemplary and should not be construed as limitations to the present invention. Those of ordinary skill in the art may make changes, modifications, replacements and variations to the above embodiments without departing from the scope of the present invention.
| Number | Date | Country | Kind |
|---|---|---|---|
| 201810448274. 5 | May 2018 | CN | national |
| Filing Document | Filing Date | Country | Kind |
|---|---|---|---|
| PCT/CN2018/116117 | 11/19/2018 | WO | 00 |
