JP2017193035A - Device for moving and positioning of element in space - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide an industrial robot for use in an industrial process including a pick-and-place (picking up and placing), which has advantages such as mechanical amplification, stability, load resisting perform, and improved dynamic characteristics.SOLUTION: An industrial robot includes a parallel kinematics mechanism, which provides three degrees of freedom to a ring structure, while keeping the ring structure in an orientation substantially fixed to a reference surface established by a static base plate. A pivot sleeve is suspended in the static base plate, and can pivot on two right angle axes of an intermediate gimbal. A slender bulging rod is attached in the pivot sleeve, and extends from an upper end to a lower end through the pivot sleeve. An end effector is attached to the lower end of the slender bulging rod, and arranged for carrying a work element. The gimbal ring is positioned at the upper end and the lower end of the slender bulging rod, and is interconnected by a control linkage so as to keep the end effector generally in parallel with the ring structure during the movement of the end effector over a three-dimentional work frame.SELECTED DRAWING: Figure 1

Description

  The present invention is intended for use in robotic technology, and more particularly in industrial processes, including pick and place operations, having the advantages of mechanical amplification, stability, load-bearing capability, and improved dynamic characteristics. For robots.

  The use of industrial robots for flexible automation of industrial processes is becoming increasingly common to replace time-consuming, tedious and difficult tasks. Such work is fast and accurate when, for example, a confectionery product such as chocolate or similar fragile or small object is carried from a conveyor belt and the object is moving on a separate conveyor belt, It can be placed in place, for example in a box. The ability to handle small and sensitive objects effectively at high speed and with high accuracy is greatly demanded in the automation of industrial processes.

  Delta robots (also known as parallel robots) have applications in various industries, for example in the food and pharmaceutical industries. Delta Robot First developed by Clav in 1985 and described in US Pat. No. 4,976,582 (Clavel). Delta robots have proved their value, especially for lightweight food packaging. Because they allow extremely high speed and high precision to perform pick and place applications, for example, to lift the products from the conveyor belt and place them in a cardboard box Can be used effectively. Delta robots are typically parallel robots that have three degrees of freedom (3 DoF) and have a simpler, smaller structure, and favorable dynamics.

  A delta robot is a parallel robot, i.e. it consists of a plurality of kinematic chains, e.g. a middle joint arm connecting a base with an end effector. An important concept for delta robots is the use of a parallelogram that limits the movement of the platform on which the end effector is mounted to a single translation, ie, movement in the X, Y, or Z direction without rotation. is there. The base of the robot is attached above the work space. A plurality of actuators, for example, three motors, are attached to the base at equal distances. From the base, three middle joining arms extend. The ends of these arms are connected to a small platform. Actuation of the middle joining arm moves the platform along the X, Y, or Z direction. Actuation can be performed with linear or rotary actuators with or without deceleration (direct drive). Since the actuators are all located within the base, the middle joining arm can be made of light composite material. As a result of this, the moving part of the delta robot has a small inertia. This allows for ultra high speed and high acceleration. Connecting all the arms together to the end effector increases the robot stiffness but reduces its workload. Each middle joint arm consists of an upper arm and a lower arm pivotally connected. Each lower arm is formed of two parallel rods that form a parallelogram. Since the lower arm consists of two parallel rods, the end effector always moves parallel to the base plate located above it. This is also known as parallelogram-based control, or parallel kinematics. Note that at least three sets of arms are required to provide generally translation-only movement of the end effector through three dimensions.

  In use, a delta robot can be suspended on a conveyor-type system to grip and move small objects quickly and with high precision. The end effector is arranged to support a tool or other device to perform a specific function or task. By pivoting the actuator, the end effector can be steered to any desired position in the available work space in the three-dimensional space formed by the X, Y, and Z axes. In addition, the end effector of a delta robot is typically equipped with a visual guidance function so that an object moving along the conveyor can be identified for lifting and placing in a cardboard box, case or the like.

  High speed movement over a relatively large distance, ie the width of the conveyor belt, requires high speed movement of several arms. This is actually possible only if the robot arm has a low mass inertia, which is achieved in the case of a delta robot by the use of lightweight materials, so that the mass inertia of the delta robot is minimized. Is done. However, the use of lightweight materials in the structure of a delta robot significantly limits the load that the delta robot can receive, which means that the delta robot can only be used to grip a light object with a light gripper. . For this reason, its usefulness and practical applications are limited. The use of stronger parts and components will provide the ability to grip heavier objects, but such benefits come at the expense of speed reduction due to high mass inertia. Also, the lightweight materials used in the construction of delta robots tend to be less robust and cannot provide a continuous production cycle time, for example a 24-hour cycle time. Also, many lightweight materials cannot provide the benefit of less maintenance and less frequent repairs, such as the stronger parts and components utilized in other types of industrial machines.

  In general, it is important that the components of the delta robot can be easily cleaned in the food industry or in pharmaceutical applications. For example, a delta robot may include a number of parts, such as arms, located in close proximity to food items such as the part of a raw chicken being carried. During operation, these parts cannot be shielded from the chicken parts, making delta robots flushing and cleaning a time-consuming and expensive task. It is an improvement within the art to provide an industrial robot in which parts and components can be shielded from food or other materials placed elevated so as to reduce or eliminate such flushing and cleaning requirements. It will be.

  Also, in many industrial processes, for example, in pick and place operations, it is important that the robot presents a wide range of motion in all directions. Due to its overall design, the traditional delta robot end effector has a limited range of motion in that the end effector does not benefit from any mechanical expansion of motion. Furthermore, a wide range of motion in the Z-axis direction is essential for lifting products from the conveyor belt and placing them in a deep cardboard box or case for transport. As a result of the design of the pivotable arm of the delta robot that extends laterally as they move through their range of motion, the laterally extending arm is moved into the cardboard box or case. Often this hinders product placement to such depths. Also, to obtain a gradual increase in range of motion in the Z-axis direction using a delta robot, the arm length needs to be increased significantly, which adds weight and reduces production cycle time.

  For the reasons described above, there is room for improvement within the field.

  The industrial robot includes a parallel kinematic mechanism that provides the ring structure with three degrees of freedom while maintaining the ring structure in a substantially fixed orientation relative to a reference plane established by a stationary base plate. A pivot sleeve can be suspended in the stationary base plate and pivoted on two perpendicular axes of the intermediate gimbal. An elongated overhanging rod is mounted within the pivot sleeve and extends from the upper end through the pivot sleeve to the lower end. An end effector is attached to the lower end of the elongated overhang and is arranged to carry the working element. The gimbal rings are located at the upper and lower ends of the elongated overhanging bar and are interconnected by the control linkage so that the end effector is maintained substantially parallel to the ring structure during the movement of the end effector across the three-dimensional work frame. Connected.

FIG. 1 is a perspective view of an embodiment of an industrial robot of the present invention located on a conveyor exemplified by perspective lines. FIG. 2 is a perspective view of the industrial robot of the present invention illustrating the overhanging bar in the lowered position. FIG. 3 is a perspective view of the industrial robot of the present invention illustrating the overhanging rod in the articulated position. FIG. 4 is an enlarged perspective view of the top portion of the preferred embodiment of the industrial robot of the present invention. FIG. 5 is an enlarged cross-sectional view taken along line 5-5 of FIG. 6 is an enlarged sectional view taken along line 6-6 of FIG. FIG. 7 is a perspective view of a preferred embodiment of the industrial robot of the present invention in another articulated position. FIG. 8 is a schematic diagram illustrating the internal linkage that holds the end effector in a fixed orientation. FIG. 9 is an enlarged cross-sectional view taken along line 9-9 of FIG. FIG. 10 is an enlarged perspective view of an end effector portion of a preferred embodiment of the industrial robot of the present invention. FIG. 11 is an enlarged perspective view of the end effector portion of the preferred embodiment of the industrial robot of the present invention when the robot is in the articulated position.

  Referring now more particularly to the drawings in which like numerals represent like components throughout the several views, an embodiment of the industrial robot of the present invention broadly designated by the numeral 20 is shown in FIGS. Indicated. In this application, the robot 20 is shown in close proximity to the conveyor belt 24, and in this application, objects (either oriented or not oriented) are lifted from the belt 24 and transported. Place it on a tray or in a cardboard box (not shown). The use of the industrial robot 20 in this high speed pick and place application is merely an example, and the robot 20 of the present invention can be utilized for other high speed applications such as assembly, as well as pharmaceutical and medical applications. I want you to understand. As best shown in FIGS. 1-7, the industrial robot 20 has a plurality of through holes 32 for attaching, for example, bolting, the base plate 28 to a suitable surface (not shown) within the production facility. A stationary base plate 28 is included.

  As best shown in FIGS. 1, 5 and 6, the base plate 28 is generally rectangular in shape and includes a central opening 36 through which an overhang bar 40 extends. The parallel kinematic structure is attached to a base plate 28 that surrounds the central opening 36. The parallel kinematic structure includes an actuator 44 attached to the base plate 28 and a control arm 48 extending upward from the actuator 44. The control arm 48 includes a parallelogram shaped link 76 that restricts the movement of the upper outer ring 52 to only a single translation, ie, movement in the X, Y, or Z direction without rotation. A parallel kinematic structure can be similar in structure to a delta robot. However, the invention contemplates other forms of parallel kinematic structures.

  As best shown in FIG. 6, the base plate 28 includes a plurality of upstanding flanges 56 a, 56 b, and 56 c that are bolted or welded thereto, which are located above the central opening 36. Together, a triangular structure 60 having welded reinforcement sections 64a, 64b, and 64c is formed. Extending radially from the triangular structure 60 are a plurality of mounting flanges 68 that are connected to the base plate 28 by any suitable means, such as welding. The plurality of actuators 44 are attached to a mounting flange 68 that utilizes any suitable hardware, such as bolts. Each actuator 44 functions as a drive source for a control arm 48 connected thereto. As best shown in FIG. 1, each control arm 48 includes a drive link 72 pivotally connected to a parallelogram link 76. In particular, each actuator 44 includes a crank that is rotated to change the position of the drive link 72 connected to the crank. This rotation allows the distal end 72 a of the drive link 72 to move upward and move downward through one of the plurality of T-shaped gap openings 80 located in the base plate 28. In the following description, “the drive link 72 rotates upward” means that the drive link 72 rotates so that the tip 72a moves upward, and “the drive link 72 rotates downward” means “the tip 72a. It shows that the drive link 72 rotates so that can move downward.

  As best shown in FIG. 1, the distal end 76 of each drive link 72 is provided with a through hole in which a rotatable swivel rod 78 having a flat end is located. Each drive link 72 is pivotally connected to a corresponding parallelogram link 76, for example, bolted, and the parallelogram link is driven in a link manner by the drive link. 1 and 4, each parallelogram link 76 includes two bar-shaped members 88 that extend generally vertically and parallel to each other between the drive link 72 and the upper outer ring 52. . As best shown in FIG. 4, the upper outer ring 52 includes a plurality of housings 96, each housing 96 being provided to receive a swivel rod 78 therein, the swivel rod 78 having its Includes a flat end rotatably mounted therein. Housing 96, eg, three housings, are connected to each other by bolting or other suitable means through connector element 100. Together, the housing 96 and the connector section 100 form an upper outer ring 52 that is generally hexagonal in shape. The hook-shaped connector 104 is fastened to the upper and lower ends of each bar-shaped member 88 by any suitable means, such as bolting. Using hook-shaped connectors fastened to both ends of each bar member 88, at their upper ends, bar members 88 can be fastened to swivel rods 78 located within each housing 96, for example, bolted obtain. At their lower ends, rod members 88 can be fastened to swivel rods 78 located at the distal ends 76 of each drive link 72 and can be bolted, for example. Together, the substantially parallel bar member 88 and the substantially parallel swivel rod 78 form the parallelogram shape of the parallelogram link 76. By connecting at least two upper ends of the parallelogram link 76 to the upper outer ring 52, the movement of the upper outer ring 52 is converted into a single translational movement (movement with only three degrees of freedom, X, Y, or Z Translation in direction). In this way, the upper outer ring 52 remains in a fixed orientation no matter what the control arm 48 moves. The plurality of control arms 48 can move in different positions relative to the base plate 28 and relative to each other between a fully raised position and a fully lowered position, substantially fixing the upper outer ring 52. The upper outer ring 52 is moved to different height and horizontal positions in three-dimensional space while maintaining the oriented orientation.

  4, 5 and 8, the upper outer ring 52 includes two axle sections 108 and 112 located on opposite ends of the periphery of the upper outer ring. The axles 108 and 112 are connected to the upper outer ring 52 by any suitable means in FIG. 4, for example, bolts 108a. The axle sections 108 and 112 are coaxial and extend inwardly from the periphery of the upper outer ring 52 to form a first upper shaft 110. As best shown in FIGS. 4 and 5, the axle 108 passes through a slot 42 a in the housing 42. Upper gimbal ring 116 is rotatably mounted on these axle sections 108 and 112. As shown in FIG. 5, the upper gimbal ring 116 is octagonal, although other shapes may be utilized within the scope of the invention. Similarly, the upper gimbal ring 116 includes two axle sections 120 and 124 located on both ends of the outer periphery of the upper gimbal ring. The axle sections 120 and 124 are along the second upper shaft 122 and extend inwardly from the periphery of the upper gimbal ring 116. The axle section of the upper gimbal ring 116 is oriented 90 degrees with respect to the axle sections 108 and 112 of the upper outer ring 52. At its upper end, the overhang bar 40 includes an octagonal housing 42 (best shown in FIGS. 4 and 5). This housing 42 of the overhang bar 40 is mounted on the axle sections 120 and 124 of the upper gimbal ring 116. In this way, the motion of the overhang bar 40 remains independent of the translational motion of the upper outer ring 52 in the X, Y, and Z directions.

  As best shown in FIGS. 1 and 4, the actuator 44 is coupled to an overhanging bar 40 above the housing 42. An overhang bar 40 connected at the bottom of the housing 42 includes a generally cylindrical portion 126 that extends below and below the upper gimbal ring 116. The cylindrical portion 126 then extends through the central opening 36 in the base plate 28 to the distal end 40b where the end effector 128 is located. As best shown in FIG. 6, the rotating shaft 132 is within the overhanging bar 40 to connect the actuator 44 coupled above the housing 42 with a tool (not shown) attached to the end effector 128. Extends centrally. The rotating shaft 132 provides unlimited rotational capability to a tool (not shown) attached to the end effector 128.

  Referring now to FIGS. 1, 5, 6, and 8, the central opening 36 of the base plate 28 serves as the middle pivot point for the pivoting movement of the overhang bar 40 therein. Specifically, the axle section 136 is provided approximately midway along the length of the upstanding flange 56c, and the opposing axle section 140 is provided approximately midway along the length of the bolted reinforcement section 64c. . Opposing axle sections 136 and 140 may be secured to upstanding flange 56c and to connected reinforcement section 64c using any suitable hardware, e.g., bolt 142. The axle sections 136 and 140 are coaxial so as to form a first central axis 138 (FIG. 8). Axle segments extend inwardly from their respective mounting surfaces. The central gimbal ring 144 is provided with a mounting hole (not shown) that allows it to be rotatably mounted on the axle sections 136 and 140 within the central opening 36 of the base plate 28. The central opening 36 is large enough to allow rotational movement of the central gimbal ring 144 therein. In this manner, the central gimbal ring 144 is free to rotate about the first central axis 138 formed by the axle sections 136 and 140. Similarly, the central gimbal ring 144 is provided with axle sections 148 and 152 attached thereto in a similar manner. The axle sections 148 and 152 are attached to the central gimbal ring 144 using any suitable hardware, located on both sides of the periphery of the central gimbal ring 144, and extend inward. The axle sections 148 and 152 define a second central axis 150 (FIG. 8) that is oriented at 90 degrees with respect to the axle sections 136 and 140 and is perpendicular to the first central axis 138. The intersection of the first and second central axes defines the middle pivot point 156 (FIG. 8). The pivot sleeve 160 is attached to the axle sections 148 and 152 of the central gimbal ring 144 and extends through the central gimbal ring 144. In this way, the middle pivot point 156 is centrally located within the pivot sleeve 160, allowing the pivot sleeve 160 to pivot in any direction about the middle pivot point 156. As best shown in FIG. 6, the overhang bar 40 extends through the pivot sleeve 160. In this way, the overhang bar 40 can pivot about the middle pivot point 156 in all directions within the central opening 36 of the base plate 28. In addition, the overhang bar 40 can freely slide up and down within the pivot sleeve 160 based on the movement of the control arm 48 from a fully lifted position to a fully lowered position.

  2, 3, and 7, the industrial robot 20 of the present invention has an end effector 128 located at the distal end 40 b of the overhang bar 40, which is movable as defined by a truncated cone 164. It has a movable range including orthogonal X, Y, and Z directions so that it can move vertically and horizontally in the region. Referring now to FIG. 2, the industrial robot 20 is illustrated therein and each control arm 48 is in its fully lowered position, and therefore the end effector 128 is moved to the Z in the range of motion 164. Lower it to its lowest position in the direction. In particular, a T-shaped gap opening 80 is provided on the base plate 28 to allow the drive link 72 to enter it, and therefore would otherwise be possible in the absence of the gap opening 80. Allows movement of the control arm to a lower position in the Z direction. Referring now to FIGS. 3 and 7, the overhang bar 40 can be utilized by moving the control arm 48 to a different position relative to each other between a fully raised position and a fully lowered position. It can be steered in three-dimensional space to any desired articulated position within possible range of motion 164, for example, pivoted. As illustrated in FIGS. 3 and 7, each control arm 48 comprises a parallelogram link so that the upper outer ring 52 is always in a substantially fixed orientation relative to the underlying base plate 28. Move. This is also known as parallelogram-based control, or parallel kinematics. The three control arms 48 provide generally translation-only movement to the upper outer ring 52 through three dimensions. Also, in FIGS. 1, 3 and 7, regardless of the position of the upper outer ring 52 in three-dimensional space, the end effector 128 to which a tool (not shown) is attached also exhibits translation-only movement through three dimensions. And is shown to remain substantially parallel to the upper outer ring 52. Such translation-only movement of the end effector is important for the use of the industrial robot 20 in the above-described applications, such as lifting and placing.

  Referring now to FIG. 8, a simplified depiction of a portion of the industrial robot 20 of the present invention is shown. The simplified depiction includes similar numbers representing similar components where applicable. At this point, it is important to note that the appearance of many of the components in FIG. 8 may differ from the other drawings in that they are merely simple and concrete. FIG. 8 is provided to illustrate the manner in which the end effector 128 exhibits translation-only motion through three dimensions and remains substantially parallel to the upper outer ring 52 regardless of the pivoting motion of the overhanging bar 40. The

  As shown in FIG. 8 and as described above with respect to other figures, the upper end of the overhang bar 40 is rotatably mounted on opposing axle sections 120 and 124 of the upper gimbal ring 116. Upper gimbal ring 116 is rotatably mounted on opposing axle sections 108 and 112 of upper outer ring 52, which axle sections form a first upper shaft 110. Opposing axle sections 120 and 124 of the upper gimbal ring 116 are oriented 90 degrees with respect to opposing axle sections 108 and 112 of the upper outer ring 52 to form a second upper shaft 122. In this way, the motion of the overhang bar 40 remains independent of the translational motion of the upper outer ring 52 in the X, Y, and Z directions. The cylindrical overhanging rod 40 extends below and through the pivot sleeve 160. As previously described, the pivot sleeve 160 is rotatably mounted on the opposing axle sections 148 and 152 of the central gimbal ring 144. The central gimbal ring 144 is rotatably mounted on opposing axle sections 136 and 140 (not shown in FIG. 8), which are mounted on the structure designated 60. First and second central axes are defined at 138 and 150, respectively, in FIG. Thereafter, the overhang bar 40 extends to its distal end 40b where the end effector 128 is located.

  Referring again to FIG. 8, the lower gimbal ring 172 is rotatably attached to the distal end 40b of the overhang bar. In particular, the lower gimbal ring 172 includes opposing axle sections 176 and 180 that extend through an opening located at the distal end 40b of the overhang bar 40. The end effector 128 is rotatably attached to the lower gimbal ring 172. In particular, end effector 128 includes opposing axle sections 188 and 192 that define a first lower shaft 190. The axle sections 188 and 192 are arranged to pass through openings in the lower gimbal ring 172, and the end effector 128 is a second lower shaft 177 defined by the opposed axle sections 176 and 180 of the lower gimbal ring 172. It is possible to rotate around a first lower shaft 190 that is substantially perpendicular to the first axis. The lower gimbal ring 172 includes an arcuate arm 208 that extends approximately 90 degrees in an arc with a connection point on the first lower shaft 190. Further, the end effector 128 includes an arc-shaped arm 204 that extends approximately 90 degrees in an arc shape, and includes a connection point on the second lower shaft 177.

  Similarly, the upper outer ring 52 is provided with an arc-shaped arm 196 extending to a connection point on the second upper shaft 122, and the upper gimbal ring 116 is connected to the connection point on the first upper shaft 110. An extending arc-shaped arm 200 is provided. The first rigid connecting rod 212 is connected to the connection point of the arc-shaped arm 196 at the upper end thereof, and is connected to the connection point of the arc-shaped arm 204 at the lower end thereof. The second rigid body connecting rod 216 is connected to the connection point of the arc-shaped arm 200 at the upper end and connected to the arc-shaped arm 208 at the lower end. The rigid connecting rods 212 and 216 are approximately equal in length. Together, through their connection to the arcuate arms of the upper outer ring 52 and upper gimbal ring 116, the connecting rods 212 and 216 limit the movement of the end effector 128 to translation-only movement through three dimensions. Useful. In this manner, the end effector 128 remains substantially parallel to the upper outer ring 52 regardless of the pivoting movement of the overhang bar 40 to which the end effector 128 is connected to the overhang bar.

  For example, as best shown in FIG. 8, when the lower end of the overhang bar 40 swings to the right along the axis 177, the lower end 40b of the overhang bar pivots out of a plane parallel to the upper outer ring 52. Will do. However, since the end effector 128 is pivotally attached to the lower gimbal ring 172 and connected to the upper outer ring 52 through the rigid connecting rod 212, the end effector 128 remains parallel to the upper outer ring 52 through this movement. It becomes.

  The actual components that form the upper arcuate arms 196 and 200 can be seen in FIG. Arcuate arm 196 is shown to bend at an angle less than 90 degrees, and arcuate arm 200 is shown to include two 45 degree bends. As best shown in FIG. 5, the distal end of the rigid connecting rod 212 is housed within a collar 214 connected to the upper arcuate arm 196. The distal end of the rigid connecting rod 216 may include a circular eye hole (not shown) that includes a central opening through which the upper arcuate arm 200 extends to connect these components. obtain.

  9-11, actual components associated with the operation of the end effector 128 are illustrated. In particular, the end effector 128 includes a housing 184 that connects at the distal end 40b (FIG. 1) of the overhang bar. Lower gimbal ring 172 has an outer surface that is generally octagonal in shape. Lower gimbal ring 172 includes opposing axle sections 176 and 180 that extend outward. Lower gimbal ring 172 is shown rotatably mounted in housing 184 by axle sections 176 and 180 extending through an opening (not shown) in housing 184. Opposing axle sections 176 and 180 define a second lower shaft 177. End effector 128 includes a cylindrical tube 128a in which a central axle section 186 is disposed. The central axle section 186 is mounted in the lower gimbal ring 172 by any suitable means that extends through the bolt plate 186b, for example, the bolt 186a. The central axle section 186 may be non-rotatable with respect to the lower gimbal ring 172, but the cylindrical tube 128a, and therefore the end effector, is rotatable about the central axle section 186. The central axle section 186 defines a first lower shaft 190 that is substantially perpendicular to the second lower shaft 177.

  As best shown in FIG. 10, two spaced L-shaped brackets 224 are shown coupled to the end effector 128 at two locations, eg, bolted. An L-shaped bracket is shown extending below the central axle section 186 and connected to a rectangular receptacle 220. A rigid connecting rod 212 is rotatably mounted within the receptacle 220 and held therein by pins 225 extending through the receptacle 220, and the spaced L-shaped brackets 224 are located on both sides of the receptacle 220. Shown. Similarly, a rigid connecting rod 216 including a trapezoidal head 216a is shown rotatably mounted on the axle section 186. As described above, at its upper end, the connecting rod 212 is connected to the upper outer ring 52, and at its upper end, the connecting rod 216 is connected to the upper gimbal ring 116. As best shown when comparing FIGS. 10 and 11, the connecting rod 212 will rotate as the overhang bar 40 articulates. Its connection to the upper outer ring 52 causes the connecting rod 212 to rotate the end effector 128 about the axle section 186 to maintain the end effector 128 substantially parallel to the upper outer ring 52.

Claims (20)

a. A stationary base plate having a central opening;
b. A ring structure arranged to receive an elongated overhang bar;
c. A parallel kinematic structure disposed between the stationary base plate and the ring structure to provide movement of the ring structure in three dimensions while maintaining the ring structure substantially parallel to the stationary base plate. Parallel kinematic structure,
d. An upper gimbal ring mounted within the ring structure and pivotable about a first axis;
e. The elongated extension bar having an upper end mounted in the ring structure and pivotable about a second axis, the second axis being substantially perpendicular to the first axis; The elongate extender bar having a length that extends through the central opening of the stationary base plate to a lower end portion; and
f. A lower gimbal ring mounted within the lower end portion of the elongate extension rod and pivotable about a third axis;
g. A first control linkage connecting the lower gimbal to the upper gimbal to maintain the lower gimbal substantially parallel to the upper gimbal during pivoting movement of the overhanging bar;
h. An end effector arranged to carry a tool and move to a different position within a three-dimensional range of motion, the end effector being attached to the lower gimbal ring and pivotable about a fourth axis An end effector, wherein the fourth axis is substantially perpendicular to the third axis;
i. A second control linkage connecting the end effector to the ring structure to maintain the end effector substantially parallel to the ring structure regardless of the position of the end effector within the three-dimensional range of motion; Equipped with industrial robots. The parallel kinematic structure is
a. A plurality of actuators fastened on the stationary base plate and disposed around the central opening;
b. A plurality of control arms movable relative to the stationary base plate and at different positions relative to each other, each driving link rotatably coupled to its respective actuator and rotating to the driving link at one end Having a driven link that is operatively coupled and rotatably coupled to the ring structure at opposite ends, the plurality of arms maintaining the ring structure substantially parallel to the stationary base plate, The industrial robot according to claim 1, comprising a plurality of control arms arranged to move to different height positions and horizontal positions.   The industrial robot of claim 2, wherein the parallel kinematic structure comprises a delta robot.   The industrial robot of claim 2, wherein the driven link comprises two spaced parallel arm sections that form a parallelogram linkage.   The industrial robot according to claim 1, wherein the three-dimensional range of motion is in the shape of a truncated cone.   The industrial robot according to claim 1, further comprising a tool attached to the end effector.   The industrial robot of claim 6, wherein the tool is selected from the group consisting of a suction tip, an air powered gripper, an electrical gripper, and a forced air tip.   The industrial robot according to claim 2, wherein each of the plurality of actuators is selected from the group consisting of a rotary servo motor, a linear motor, a stepping motor, an electric motor, a hydraulic cylinder, and a pneumatic cylinder.   The industrial robot of claim 1, further comprising a central gimbal ring mounted within the central opening of the stationary base plate and pivotable about a fifth axis.   A sleeve mounted within the central gimbal ring and pivotable about a sixth axis, the sixth axis being substantially perpendicular to the fifth axis, wherein the sleeve is disposed therein; The industrial robot of claim 9, wherein the industrial robot is arranged to allow sliding movement of the elongated bar.   The upper gimbal ring further comprises an arcuate arm extending from a point along the second axis to a free end located at a point along the first axis, and the lower gimbal ring is connected to the third axis An arcuate arm extending from a point along the arc to a free end located at the point along the fourth axis, the first control linkage being connected to the free end of the arcuate arm. Item 2. The industrial robot according to Item 1.   The upper ring structure further includes an arc-shaped arm extending from a point along the first axis to a free end located at a point along the second axis, and the end effector is connected to the fourth axis. An arcuate arm extending in an arc from a point along the axis to a free end located at the point along the third axis, wherein the second control linkage is connected to the free end of the arcuate arm The industrial robot according to claim 11.   The industrial robot of claim 1, wherein the elongated bar is mounted in the upper gimbal ring.   The first control linkage comprises an inflexible rod having a length, the second control linkage comprises an inflexible rod having a length, and the lengths of the first and second control linkages The industrial robot according to claim 1, wherein the lengths are substantially equal.   The industrial robot according to claim 1, wherein the overhang bar includes a portion that is substantially cylindrical.   The industrial robot according to claim 2, wherein the plurality of actuators include at least three driving units.   The industrial robot according to claim 2, wherein the plurality of actuators are turned through a predetermined arc. The stationary base plate includes a notch corresponding to each control arm, and the notch is associated with each control arm when the notch moves to a position where the control arm is fully lowered. The industrial robot according to claim 17, wherein the industrial robot is allowed to pass therethrough.   The industrial robot of claim 6, wherein the end effector provides unlimited rotational motion over 360 degrees.   The industrial robot according to claim 2, wherein the driven link constitutes a parallelogram link including a parallel bar-shaped member.