Conveyance mechanism

Abstract

[Problem] To provide a conveyance mechanism that can be installed in a space-constrained workspace in a factory or the like where workpieces are machined using machine tools, conveys the workpiece between a workpiece placement area in the machine tool and an area around the machine tool, and can be constructed using relatively inexpensive parts. [Solution] A conveyance mechanism A is provided with an X-axis movement mechanism 1, a Y-axis movement mechanism 2, a Z-axis movement mechanism 3, a hand unit 4, and a main control unit 5. The hand unit 4 has a main frame 40, a motor 41, a worm part 42, a worm wheel 43, a planetary gear 44, and a chuck part 45. The hand unit 4 grips the workpiece placed on a workpiece placement part or a processing chuck part, and holds the workpiece when the workpiece is conveyed by each movement mechanism.

Description

Conveyor mechanism

[0001] The present invention relates to a transport mechanism, specifically to a transport mechanism that can be installed in a space-limited workspace in a factory or the like where workpieces are machined using machine tools, transports workpieces between a workpiece placement area within the machine tool and an area surrounding the machine tool, and can be constructed using relatively inexpensive components.

[0002] 2. Description of the Related Art Conventionally, a heavy workpiece made of casting or the like is supplied to a machine tool such as an NC-controlled device, and precision machining or the like is performed on the workpiece to finish it into a machine part.

[0003] For an operator to manually attach and detach such a heavy workpiece, for example, a workpiece weighing 10 kg or more, to and from a designated chuck portion in a machine tool is a heavy burden.

[0004] To reduce the burden on workers, a hoist crane or the like is installed on the ceiling of the factory, and a transport mechanism is used to suspend and transport the workpiece.

[0005] Here, when transporting the workpiece using a crane or the like, the workpiece must be attached to the crane or the chuck of the machine tool each time, which reduces the burden of transporting heavy objects but still requires a lot of work.

[0006] In this context, a technology has been proposed in which a robot arm is used to automatically transport a workpiece instead of a transport mechanism such as a crane.

[0007] For example, the robot arm described in Patent Document 1 has a multi-jointed cantilever shape and is configured to be capable of transporting a heavy workpiece.

[0008] Furthermore, conventional robot arms are configured to precisely position the temporary placement position of the workpiece and the position of the chuck part of the machine tool based on coordinate information, and then move the robot arm accurately to the determined position.

[0009] Japanese Patent Application Laid-Open No. 2023-019416

[0010] However, when attempting to transport a heavy workpiece using conventional robot arms, including the robot arm described in Patent Document 1, there was a problem in that the robot arm itself became large.

[0011] That is, for example, when trying to grasp a heavy workpiece with a robot arm and transport it accurately to a target position, the first joint, which is installed on the floor surface of the robot arm or the like, must be enlarged in order to ensure stable transport.

[0012] On the other hand, in factories where workpieces are machined, it is not uncommon for machine tools to take up a large amount of space within a limited work area, with the surrounding area also serving as an aisle within the factory, a work area for workers, and a temporary storage area for workpieces.

[0013] In such a space-limited workspace, it is difficult to install a large robot arm near the machine tool.

[0014] Furthermore, in order to ensure accurate driving, robot arms used to transport workpieces use expensive components such as ball screws and servo motors, which means that installing the robot arm requires a large amount of cost.

[0015] The present invention has been devised in consideration of the above points, and aims to provide a transport mechanism that can be installed in a work space with limited space in a factory or the like where workpieces are machined using machine tools, that transports workpieces between the workpiece placement area within the machine tool and the area surrounding the machine tool, and that can be constructed using relatively inexpensive components.

[0016] In order to achieve the above object, the transport mechanism of the present invention is a transport mechanism that transports a workpiece, which is to be machined by a predetermined machine tool and has a predetermined weight, between a workpiece temporary placement area and a placement area within the predetermined machine tool, and includes a main frame that is a plate-like body with a predetermined through-hole formed therein and has a workpiece fitting portion formed on its bottom side for fitting with the workpiece, a motor attached to the top surface of the main frame and serving as a drive source, a worm portion that rotates based on the driving force of the motor, a ring-shaped worm wheel that transmits power by meshing with the worm portion, a plurality of planetary gears that are arranged on the outside of the worm wheel and transmit power by meshing with the worm wheel, a plurality of gear rollers that are rotatably attached to the top surface of the main frame and are arranged inside the worm wheel to support the worm wheel, and a chuck portion that is paired with the planetary gear and that grips or separates the workpiece fitted in the workpiece fitting portion as the planetary gear rotates; a camera sensor attached to the top surface at a position corresponding to the predetermined through-hole and having an imaging means on the bottom side; a columnar body provided parallel to the Z-axis direction which is a vertical direction, the hand unit being disposed below the columnar body, and a Z-axis drive mechanism which enables the hand unit to move up and down along the Z-axis direction; and a Z-axis drive mechanism which enables the Z-axis drive mechanism to move along an X-axis direction which is a direction along an edge of the predetermined machine tool and which is a direction perpendicular to the Z-axis direction, and an X-axis movement path is provided above the predetermined machine tool. the Z-axis drive mechanism is provided with an X-axis drive mechanism, a Y-axis drive mechanism that enables the Z-axis drive mechanism to move along the Y-axis direction, which is a direction perpendicular to both the Z-axis direction and the X-axis direction, and has a Y-axis movement path provided above the X-axis movement path; and a rotation drive mechanism that is provided above the Y-axis drive mechanism, connects the Z-axis drive mechanism to the Y-axis drive mechanism, has a support arm that supports the Z-axis drive mechanism, and is configured so that the longitudinal direction of the support arm can be rotated between a direction parallel to the Y-axis direction and a direction perpendicular to the Y-axis direction.

[0017] Here, the rotational speed of the driving force generated by the motor can be reduced and torque increased by using a motor attached to the top side of the main frame as the driving source, a worm part that rotates based on the driving force of the motor, and a ring-shaped worm wheel that transmits power by meshing the worm part with a gear.

[0018] Furthermore, the hand unit has a worm wheel and multiple planetary gears that are arranged on the outside of the worm wheel and transmit power by meshing with the gears, so that multiple planetary gears can be rotated while increasing torque based on the driving force generated by a single motor.Furthermore, because multiple planetary gears can be rotated with a single motor, the size of the hand unit can be reduced.

[0019] Furthermore, the hand unit is a plate-shaped body and has a main frame with a work fitting portion formed on its bottom side that fits into the work, and a chuck portion that is paired with the planetary gear and grips or separates the work fitted into the work fitting portion as the planetary gear rotates.By fitting the work into the work fitting portion and gripping it with the chuck portion, it is possible to transport the work stably.

[0020] Furthermore, the hand unit has a motor, a worm portion, a worm wheel, and multiple planetary gears, and the chuck portion grips the workpiece fitted in the workpiece fitting portion as the planetary gear rotates, so that even if the motor stops due to a power outage, etc., the chuck portion gripping the workpiece can be prevented from separating the workpiece and dropping it. That is, for example, even if an external force acts on the hand unit when the motor stops due to a power outage, etc., the worm portion, worm wheel, and multiple planetary gears do not rotate due to the external force, so the chuck portion does not move and the workpiece can be maintained in its gripped state, preventing the workpiece from dropping from the hand unit.

[0021] Furthermore, by disposing a plurality of gear rollers inside the worm wheel and supporting the worm wheel, it is possible to secure a space inside the worm wheel while supporting the worm wheel with a plurality of gear rollers. In this way, since a space inside the worm wheel is secured, when a camera sensor is attached to the main frame, a portion of the camera sensor can be localized in the space inside the worm wheel, making it easier to position the camera sensor in a position suitable for imaging.

[0022] Furthermore, by attaching a camera sensor to the top surface of the main frame at a position corresponding to a predetermined through-hole and providing an imaging means on the bottom surface, the camera sensor can recognize the position of the workpiece by capturing an image of the workpiece with the imaging means before it is grasped by the hand unit. In other words, the image information from the imaging means can be used to confirm the position of the workpiece before it is grasped and the general outline of the workpiece. Based on this image information from the imaging means, the hand unit can be moved to a position where the workpiece fits into the workpiece fitting section.

[0023] In addition, the Z-axis drive mechanism is a columnar body arranged parallel to the Z-axis direction, which is the vertical direction, and the hand unit is placed below it, and by making it possible to raise and lower the hand unit along the Z-axis direction, the hand unit can be moved along the Z-axis direction.

[0024] Furthermore, by making the X-axis drive mechanism movable along the X-axis direction, which is a direction along the edge of a predetermined machine tool and perpendicular to the Z-axis direction, the hand unit can be moved along the X-axis direction. Also, the hand unit can be moved along a direction parallel to the edge of the machine tool.

[0025] Furthermore, the Y-axis trajectory mechanism enables the Z-axis drive mechanism to move along the Y-axis direction, which is perpendicular to both the Z-axis direction and the X-axis direction, thereby allowing the hand unit to move along the Y-axis direction.

[0026] In addition, the rotation drive mechanism is provided on top of the Y-axis drive mechanism, connects the Z-axis drive mechanism to the Y-axis drive mechanism, and has a support arm that supports the Z-axis drive mechanism.The longitudinal direction of the support arm is configured to be rotatable between a direction parallel to the Y-axis direction and a direction perpendicular to the Y-axis direction, so that the hand unit can be rotated within a certain range along the plane formed by the X-axis direction and the Y-axis direction.

[0027] Furthermore, by providing an X-axis movement path above the specified machine tool in the X-axis drive mechanism and a Y-axis movement path above the X-axis movement path, and by providing a rotation drive mechanism above the Y-axis drive mechanism and having a support arm that connects the Z-axis drive mechanism and the Y-axis drive mechanism and supports the Z-axis drive mechanism, it is possible to provide a movement path above the specified machine tool for moving the Z-axis drive mechanism and hand unit along the X and Y axes. This makes it possible to utilize the space above the specified machine tool to arrange a transport mechanism, and to reduce the proportion of the floor space, etc., occupied by the transport mechanism in a factory, etc.

[0028] The camera sensor also includes a cross-section measurement means for acquiring unevenness data of the workpiece via an infrared laser, and is capable of recognizing the predetermined workpiece outer shape and the position of a marker attached to the workpiece via the imaging means. When estimating the estimated center position of the workpiece based on the unevenness data acquired by the cross-section measurement means, the position of the workpiece fitting portion can be moved to match the position and orientation of the workpiece placed in the temporary workpiece placement area or the predetermined machine tool placement area via the camera sensor and cross-section measurement means. That is, the imaging means recognizes the outer shape of the workpiece and the position of the marker attached to the workpiece. Furthermore, based on the position of the marker attached to the workpiece, the rotation direction required to fit the workpiece into the workpiece fitting portion in the appropriate orientation can be determined. Furthermore, the infrared laser is scanned in two mutually orthogonal axial directions (X and Y directions centered on the camera sensor) based on the camera sensor to acquire unevenness data of the workpiece, thereby estimating the theoretical center position of the workpiece. Based on this theoretical center position of the workpiece, the positional relationship between the workpiece fitting portion and the workpiece can be determined, and the hand unit can be moved to a position where the workpiece can be accommodated and grasped inside the workpiece fitting portion. Furthermore, since it is sufficient for the imaging means to be able to recognize the approximate outline of the workpiece and the markers, a camera sensor can be constructed using a relatively inexpensive imaging means.

[0029] Furthermore, if the hand unit is provided with a position recognition control unit that controls the operation of the camera sensor and controls the recognition process of the workpiece position, the position recognition control unit can automatically control the operation of the camera sensor to move the hand unit to a position where the workpiece can be accommodated and grasped inside the workpiece fitting portion.

[0030] Furthermore, if the gear roller has a V-shaped groove formed on its outer surface with a recess in approximately the center along the Z-axis direction, and the worm wheel has a convex portion formed on its inner surface along the Z-axis direction that fits into the V-shaped groove, the V-shaped groove and the convex portion can be fitted together, allowing the gear roller to stably support the worm wheel.

[0031] Furthermore, when viewed from the front, the teeth of the worm wheel are formed so that they are inclined at a certain angle in one direction relative to the axis of the worm wheel, and a linear taper is provided on the outer peripheral surfaces of the teeth along the Z-axis direction from the top surface to the bottom surface so that the diameter of the worm wheel increases, and when the teeth of the planetary gears are formed so that they are inclined at a certain angle in the opposite direction to the axis of the worm wheel, and a linear taper is provided on the outer peripheral surfaces of the teeth along the Z-axis direction from the top surface to the bottom surface so that the diameter of the planetary gear increases, the range of meshing between the teeth of the worm wheel and the teeth of the planetary gear becomes sufficiently large, and power can be transmitted from the worm wheel to the planetary gear, ensuring the movement of rotating the planetary gear.

[0032] Also, inside the planetary gear, there is a ring base, which is a cylindrical body attached to the planetary gear, has a hole formed on the inner peripheral surface thereof and rotates together with the planetary gear, and a columnar body partially inserted into the hole of the ring base, has a second screw groove formed on its outer peripheral surface which abuts against the inner peripheral surface of the hole and which engages with the first screw groove, and its rotation about its axis is restricted, and it is equipped with a lift bolt that rises and falls in the Z-axis direction as the ring base rotates, and the chuck portion is approximately U-shaped and is rotatably supported on the main frame, and the bottom surface of its protruding upper side is pressed against the upper end of the rising lift bolt, causing the chuck portion to rotate, and when the protruding lower part grips the workpiece fitted in the work fitting portion, the power of rotation of the planetary gear can be converted into the movement of the lift bolt rising and falling from the ring base, thereby rotating the chuck portion. In other words, with a small number of parts and a compact structure, the power that rotates the planetary gears can be transmitted to rotate the chuck portion. Furthermore, with this structure, the worm wheel that rotates the planetary gears does not rotate even when an external force is applied, and therefore the planetary gears and the lifting bolts do not move due to an external force, and the chuck portion does not rotate due to an external force, so that the workpiece can be maintained in a gripped state even if the motor stops due to a power outage, for example.

[0033] Furthermore, if the Z-axis drive mechanism includes a Z-axis motor serving as a drive source, a Z-axis worm that rotates based on the driving force of the Z-axis motor, a Z-axis worm reducer consisting of a Z-axis worm wheel that transmits power by meshing with the Z-axis worm, a Z-axis chain attached to the Z-axis worm wheel and capable of winding up and letting out along the Z-axis direction as the Z-axis worm wheel rotates, a movable pulley attached to the Z-axis chain and rising and falling as the Z-axis chain is wound up and let out, and a base disposed below the movable pulley, supporting the movable pulley for rotation and having a hand unit disposed therebelow, the power mechanism of the Z-axis drive mechanism can be constructed using relatively inexpensive components via the Z-axis motor, the Z-axis worm reducer, and the Z-axis chain. Furthermore, because the reduction ratio can be increased by the Z-axis worm reducer, a small motor can be used as the power source for the Z-axis motor. Furthermore, as described above, when gripping a workpiece with the chuck portion, the position of the target workpiece can be recognized via the camera sensor and the workpiece can be gripped, so movement along the Z-axis by the Z-axis drive mechanism does not require strict movement control like a movement mechanism that uses a ball screw, and movement can be performed using a chain.

[0034] Furthermore, if the weight, including the weight of the hand unit, allows it to be positioned at the lowest position within the lifting range of the hand unit in the Z-axis direction, the accuracy of movement along the Z-axis can be improved even if backlash (gap) exists in the direction of gear movement when driving the Z-axis worm reducer. In other words, by positioning the hand unit at the lowest position due to the weight, including the weight of the hand unit, during movement along the Z-axis, deviations in movement caused by backlash are absorbed. Then, by raising the hand unit from the lowest position as the starting point of movement in the Z-axis direction, the accuracy of movement can be improved without considering backlash.

[0035] Furthermore, the X-axis drive mechanism is composed of a base plate that serves as the main body of the moving body, an X-axis motor that serves as a drive source, an X-axis reducer that outputs torque from the drive force of the X-axis motor, and an X-axis sprocket that rotates with the output torque from the X-axis reducer, and has an X-axis moving part attached to the base plate, and the X-axis movement path is composed of X-axis steel members made of two steel members parallel to the X-axis direction, and an X-axis chain member that is a chain member with both ends fixed and parallel to the X-axis direction and stretched between the two steel members, and the X-axis sprocket is fitted onto the top of the X-axis chain member and rotates, so that the X-axis moving part and base plate move along the X-axis steel member and the X-axis chain member.In this case, the power mechanism of the X-axis drive mechanism can be constructed using relatively inexpensive parts via the X-axis motor, X-axis reducer, X-axis sprocket, X-axis chain, and X-axis steel member. Furthermore, as described above, when gripping a workpiece with the chuck portion, the position of the target workpiece can be recognized via the camera sensor and the workpiece can be gripped. Therefore, movement along the X-axis by the X-axis drive mechanism does not require strict movement control as with a movement mechanism that uses a ball screw, and movement can be performed using a chain.

[0036] The Y-axis drive mechanism is composed of a Y-axis motor as a drive source, a Y-axis reducer that outputs torque from the driving force of the Y-axis motor, and a Y-axis sprocket that rotates with the output torque from the Y-axis reducer, and has a Y-axis moving part attached to the base plate, and the Y-axis moving path is made up of a Y-axis steel material that is a single steel material that is arranged above the base plate and is oriented perpendicular to the X-axis steel material, and a Y-axis moving part that is provided above the base plate and is attached to the Y-axis steel material and is movable along the Y-axis steel material. The Y-axis drive mechanism is configured with a shaft fitting portion and a Y-axis chain portion tensioned parallel to the Y-axis direction, and the Y-axis sprocket is fitted onto the upper portion of the Y-axis chain portion and rotates, so that the Y-axis moving portion and base plate move along the Y-axis steel and the Y-axis chain portion. The Y-axis drive mechanism can be constructed with relatively inexpensive components via the Y-axis motor, Y-axis reducer, Y-axis sprocket, Y-axis chain, and Y-axis steel. Furthermore, as described above, when the workpiece is gripped by the chuck portion, the position of the target workpiece can be recognized via a camera sensor, and the workpiece can be gripped. Therefore, the movement along the Y-axis by the Y-axis drive mechanism does not require strict movement control as in a movement mechanism that uses a ball screw, and the movement can be performed using a chain.

[0037] Furthermore, if the Y-axis drive mechanism can move the front Z-axis drive mechanism along the Y-axis direction to a position beyond the edge of the specified machine tool, it becomes possible to move the Z-axis movement mechanism and hand unit to a position outside the edge of the specified machine tool and not interfere with the specified machine tool. This increases the degree of freedom in the location of the temporary workpiece placement area where the workpiece is placed before and after processing, resulting in a transport mechanism that contributes to further labor savings and improved work efficiency.

[0038] Furthermore, if a pan-tilt mechanism is provided that is disposed between the Z-axis movement mechanism and the hand unit, connects the Z-axis movement mechanism to the hand unit, and enables the hand unit to rotate in horizontal directions parallel to the X-axis and Y-axis directions, and also enables the hand unit to rotate in the Z-axis direction, the hand unit can be moved with even greater freedom. In other words, the orientation of the camera sensor and the orientation of the workpiece grasped by the hand unit can be changed with even greater freedom. As a result, the positions and orientations of the workpieces that can be recognized by the camera sensor can be diversified, and the variety of positions and orientations at which the hand unit can grasp or separate the workpieces increases, greatly expanding the transport routes and ranges that can be accommodated by the transport mechanism and the structure of the machine tool.

[0039] The transport mechanism of the present invention can be installed in a work space with limited space in a factory or the like where workpieces are processed using machine tools, transports workpieces between the workpiece placement area within the machine tool and the area surrounding the machine tool, and can be constructed using relatively inexpensive components.

[0040] 9A is a schematic perspective view showing a state in which a transfer mechanism according to an embodiment of the present invention is installed in a processing apparatus, and FIG. 9B is a schematic plan view of the view shown in FIG. 1A. FIG. 9B is a schematic perspective view showing a hand unit and a Z-axis movement mechanism and their peripheral structure. FIG. 9C is a schematic perspective view of the entire structure of the hand unit, as viewed obliquely from above. FIG. 9A is a schematic plan view of the view shown in FIG. 3, and FIG. 9B is a schematic perspective view of the view shown in FIG. 3, as viewed obliquely from below. FIG. 9C is a schematic cross-sectional view showing a gear roller in the hand unit and its peripheral structure. FIG. 9D is a schematic cross-sectional view showing a push bolt in the hand unit and its peripheral structure. FIG. 9D is a diagram showing the gear structure of a worm wheel and a planetary gear, with FIG. 9A being a schematic plan view, FIG. 9B being a schematic perspective view, and FIG. 9C being a schematic front view. FIG. 9E is a schematic front view showing the gear structure of a conventional worm wheel. FIG. 9F is a schematic perspective view showing the entire structure of the Z-axis movement mechanism, and FIG. 9F is a schematic perspective view partially showing the internal structure of the view shown in FIG. 9A. 1A and 1B are schematic perspective views partially showing the internal structure of the upper side of the Z-axis moving mechanism, and 1C is a schematic perspective view partially showing the internal structure of the lower side of the Z-axis moving mechanism. 1A is a schematic perspective view showing the overall structure of the X-axis moving mechanism, the Y-axis moving mechanism, and the Z-axis moving mechanism, and 1B is a schematic perspective view partially showing the X-axis H-beam and the X-axis chain. 1C is a schematic perspective view showing the hanging arm, the arm pan unit, the Y-axis steel material, and their peripheral structures. 1C is a schematic perspective view showing the X-axis moving unit and the Y-axis moving unit, and their peripheral structures. 1C is a schematic perspective view of the moving body plate, viewed obliquely from below. 1C is a partial schematic perspective view showing the drive sprocket of the X-axis moving unit, and its peripheral structures. 1C is a schematic sectional perspective view of the internal structure of the drive sprocket of the X-axis moving unit, and its peripheral structures.

[0041] Hereinafter, an embodiment of the present invention will be described to facilitate understanding of the present invention. A transfer mechanism A, which is an example of a transfer mechanism to which the present invention is applied, will be described. In the following example, the description will be based on a structure in which the transfer mechanism A is provided for a processing device B, which is an NC-controlled device (see FIGS. 1(a) and 1(b)).

[0042] In the following description, the left-right direction on the paper surface is referred to as the X-axis direction, the right side on the paper surface is referred to as the right or right side, and the left side on the paper surface is referred to as the left or left side, based on Fig. 1(b). The up-down direction on the paper surface is referred to as the Y-axis direction, the lower side on the paper surface is referred to as the front or forward, and the upper side on the paper surface is referred to as the rear or rearward. The X-axis direction and the Y-axis direction may also be referred to as the horizontal direction.

[0043] 1(b) as a reference, a direction perpendicular to the X-axis direction and the Y-axis direction and penetrating the paper surface is referred to as the Z-axis direction or vertical direction. Also, with reference to FIG. 1(b) as a reference, the back side in the direction penetrating the paper surface is referred to as the bottom or lower side, and the front side in the direction penetrating the paper surface is referred to as the top or upper side.

[0044] Here, the processing device B is a processing device that performs precision machining using NC control on a workpiece formed from casting, and finishes it into an indirect part of a robot arm. The workpiece weighs 10 kg or more and has a hollow shape with a through-hole formed in the center (not shown). Note that many of the indirect parts of robot arms have a hollow shape so that wires for signal transmission and power supply can be inserted through them.

[0045] The machining device B here corresponds to the predetermined machine tool in the claims of the present application, and the workpiece here corresponds to the member in the claims of the present application.

[0046] In the processing device B, the workpiece to be processed is attached to a processing chuck (not shown) provided in the work space B1 (see FIGS. 1(a) and 1(b)), and the drive door B2 is closed to block off the work space B1, and the workpiece is processed inside the device. Note that FIGS. 1(a) and 1(b) show the drive door B2 in an open state.

[0047] In addition, the transport mechanism A is installed in a factory where the processing device B is installed, and is a mechanism that transports workpieces between a workpiece placement section (not shown) installed around the processing device B in the factory and the processing chuck section of the processing device B.

[0048] The machining chuck portion referred to here is a portion that corresponds to the placement area in a predetermined machine tool in the claims of the present application, and the workpiece placement portion referred to here is a member that corresponds to the temporary placement area for the workpiece in the claims of the present application.

[0049] Furthermore, in the transport mechanism A, multiple workpiece placement sections can be provided at any position around the processing device B within the range in which the hand unit 4 can be moved via various movement mechanisms described below.

[0050] For example, a workpiece placement section can be provided where an operator transports the workpiece before processing and prepares the workpiece, and a workpiece placement section can be provided where the processed workpiece is removed from the processing device B and temporarily placed thereon.

[0051] 1(a) and 1(b), the transport mechanism A includes an X-axis movement mechanism 1, a Y-axis movement mechanism 2, a Z-axis movement mechanism 3, a hand unit 4, and a main control unit 5. The X-axis movement mechanism 1 is provided above the processing device B via a gantry unit G installed around the processing device B.

[0052] Here, the X-axis movement mechanism 1 is a mechanism for moving the hand unit 4 along the X-axis direction (left and right direction), the Y-axis movement mechanism 2 is a mechanism for moving the hand unit 4 along the Y-axis direction (front and back direction), and the Z-axis movement mechanism 3 is a mechanism for moving the hand unit 4 along the Y-axis direction (up and down direction or vertical direction).

[0053] The hand unit 4 is a mechanism that grips a workpiece placed on the workpiece placement section or the processing chuck section, and also holds the workpiece when transporting the workpiece via each moving mechanism.

[0054] The X-axis moving mechanism 1, the Y-axis moving mechanism 2, and the Z-axis moving mechanism 3 referred to here correspond to the X-axis moving mechanism, the Y-axis moving mechanism, and the Z-axis moving mechanism in the claims of the present application, respectively. Also, the hand unit 4 referred to here corresponds to the hand unit in the claims of the present application.

[0055] The main control unit 5 is also the main control unit that controls a coordinate movement CPU (not shown) that controls movement via each of the X-axis movement mechanism 1, Y-axis movement mechanism 2, and Z-axis movement mechanism 3, and a position recognition CPU that controls the driving of the camera sensor 6, which will be described later.

[0056] 2, the Z-axis movement mechanism 3 has a Z-axis drive unit 30 and a pull arm 31. A pan unit 3000 and a tilt unit 3010 are provided below the pull arm 31. A hand unit 4 is attached to the lower side of the tilt unit 3010.

[0057] The Z drive unit 30 is a drive source for raising and lowering the hand unit 4 in the Z-axis direction while extending and retracting the pull arm 31. The detailed structure of the Z-axis movement mechanism 3 will be described later.

[0058] The pan unit 3000 is a drive mechanism for rotating the hand unit 4 horizontally, and the tilt unit 3010 is a drive mechanism for rotating the hand unit 4 vertically (longitudinal).

[0059] By providing the pan unit 3000 and the tilt unit 3010, it becomes possible to rotate the hand unit 4 in the horizontal and vertical directions, thereby adjusting the orientation of the hand unit 4 with a high degree of freedom.

[0060] The pan unit 3000 and tilt unit 3010 referred to here correspond to the pan-tilt mechanism in the claims of the present application.

[0061] Next, a detailed description will be given of the structure of the hand unit 4. As shown in Fig. 3, the hand unit 4 has a main frame 40, a motor 41, a worm portion 42, a worm wheel 43, a planetary gear 44, and a chuck portion 45.

[0062] The main frame 40 is the main body of the hand unit 4 and serves as a base on which components such as the motor 41, worm portion 42, planetary gear 44, and chuck portion 45 are attached. The worm wheel 43 is attached above the main frame 40 via a gear roller 47, which will be described later.

[0063] The motor 41 is a member that generates a driving force for driving a chuck 45 that grips or separates a workpiece. The worm 42 and the worm wheel 43 are a reducer that transmits the driving force of the motor 41 and generates torque.

[0064] The planetary gear 44 is a member that drives the chuck portion 45 based on the driving force transmitted via the worm wheel 43 .

[0065] Additionally, three planetary gears 45 are provided on the outer side of one worm wheel 43, and one planetary gear 45 is paired with one chuck portion 45. In other words, when one worm wheel 43 rotates, three planetary gears 45 are simultaneously rotated, and the three chuck portions 45 can be driven in conjunction with each other.

[0066] The main frame 40 referred to here corresponds to the main frame in the claims of the present application. The motor 41 referred to here corresponds to the motor in the claims of the present application. The worm portion 42 and the worm wheel 43 referred to here correspond to the worm portion and the worm wheel in the claims of the present application.

[0067] The planetary gear 44 here corresponds to the planetary gear in the claims of the present application, and the chuck portion 45 here corresponds to the chuck portion in the claims of the present application.

[0068] Three tension springs 46 are attached to the top of the chuck portions 45 (see FIGS. 3 and 4A). These tension springs 46 are attached to the top of adjacent chuck portions 45, and are members that bias the lower ends of the chuck portions 45 so that they are positioned at the outermost positions when the hand unit 4 is not gripping a workpiece.

[0069] The main frame 40 has a substantially disk-shaped upper frame 400 and a substantially cylindrical lower frame 410 provided below the upper frame 400 (see FIGS. 4(a) and 4(b)).

[0070] The upper frame 400 has a motor 41 and other components attached thereto, and a rectangular through-hole 401 formed in the center thereof, with a camera sensor 6 (described later) attached at a position corresponding to the through-hole 401 (see FIGS. 4(a) and 4(b)). By providing the camera sensor 6 at the position of the through-hole 401, the camera sensor 6 can capture an image of the area below the hand unit 4.

[0071] Furthermore, by providing the lower frame 410 on the bottom surface of the upper frame 400, a recess 411 is formed on the inside of the lower frame 410. Furthermore, a plurality of recesses 412 are formed on the outer circumferential surface of the lower frame 410. The lower frame 410 is a portion into which a workpiece fits when the workpiece is gripped by the hand unit 4.

[0072] Furthermore, when the workpiece is fitted into the lower frame 410, the main body of the workpiece is accommodated in the recess 412, and the protrusions of the workpiece fit into the recesses 411 of the lower frame 410, so that the workpiece can be held by the chuck portion 45 while being positioned horizontally relative to the lower frame 410.

[0073] Here, the shape of the lower frame 410 can be formed appropriately to match the shape of the workpiece to be gripped by the hand unit 4 .

[0074] 3 and 4A, four gear rollers 47 are provided on the main frame 40 at positions inside the worm wheel 43. The gear rollers 47 are rotatably attached to the top surface of the main frame 40 and are members that support the worm wheel 43.

[0075] The gear roller 47 here corresponds to the gear roller in the claims of the present application.

[0076] More specifically, as shown in FIG. 5, one gear roller 47 is made up of a gear roller shaft 470 , a bearing 471 and a drum-shaped roller 472 .

[0077] In addition, the lower side of the gear roller shaft 470 is fixedly embedded in a part of the upper surface of the upper frame 400 of the main frame 40, and a drum-shaped roller 472 is attached to the outer peripheral surface of the upper side of the gear roller shaft 470 via a bearing 471 so as to be freely rotatable.

[0078] 5, a convex portion 430 whose central portion protrudes inward in the thickness direction is formed on the inner peripheral surface of the worm wheel 43. Furthermore, a V-shaped groove portion 473 whose central portion is recessed inward in the thickness direction is formed on the outer peripheral surface of the drum-shaped roller 472.

[0079] The convex portions 430 of the worm wheel 43 fit into the V-shaped grooves 473 of the hourglass-shaped rollers 472, thereby enabling the multiple hourglass-shaped rollers 472 to stably support the worm wheel 43 from the inside. When the worm wheel 43 rotates, the hourglass-shaped rollers 472 also rotate, thereby achieving smooth rotation of the worm wheel 43.

[0080] Furthermore, this structure of support using multiple drum-shaped rollers 472 eliminates the need to insert a columnar shaft inside the worm wheel 43 and support the worm wheel 43 using two large bearings, one above and one below, etc., and space can be secured inside the worm wheel 43.

[0081] In this way, since a space can be secured inside the worm wheel 43, it is possible to arrange the camera sensor 6 inside the worm wheel 43, that is, at a position approximately in the center of the main frame 40.

[0082] As a result, it becomes possible for the camera sensor 6 to capture an image of the area below the hand unit 4 from a position approximately in the center of the hand unit 4 .

[0083] The convex portion 430 referred to here corresponds to the convex portion in the claims of the present application, and the V-shaped groove portion 473 referred to here corresponds to the V-shaped groove in the claims of the present application.

[0084] Next, the planetary gear 44, the chuck portion 45, and the surrounding structure will be described with reference to Fig. 6. As shown in Fig. 6, a cylindrical push ring 440 is provided on a part of the upper surface of the upper frame 400 and inside the planetary gear 44.

[0085] The push ring 440 is configured to rotate integrally with the planetary gear 44. A screw groove 441 is formed on the inner peripheral surface of the hole of the push ring 440. A push bolt 442 is attached to the inside of the hole of the push ring 440.

[0086] The push bolt 442 has a lower side 443 formed in a cylindrical shape and an upper side 444 formed in a partial rectangular column shape. A screw groove 445 is formed on the outer peripheral surface of the lower side 443. An arch-shaped guide portion 446 is provided above the planetary gear 44, and a rectangular hole 447 is formed on the upper side of this guide portion 446, through which the upper side 44 of the push bolt 442 can be inserted.

[0087] A screw groove 445 on the lower side 443 of the push bolt 442 is threadedly fitted into a screw groove 441 on the inner peripheral surface of the hole of the push ring 440, and the push bolt 442 moves up and down as it rotates. In addition, this structure of vertical movement due to the threaded fitting generates a large torque, and a large gripping force can be generated via the chuck portion 45.

[0088] Furthermore, the partial rectangular column shape of the upper side 444 of the push bolt 442 fits into the rectangular hole 447 of the guide portion 446, thereby restricting the rotational movement of the push bolt 442 when it moves up and down.

[0089] The push ring 440 here corresponds to the ring base in the claims, and the push bolt 442 here corresponds to the lift bolt in the claims.

[0090] 6, the chuck portion 45 has a generally U-shaped configuration and is composed of an upper piece 450, a main body 451, and a lower piece 452. The main body 451 is rotatably attached to the upper frame 400 via a rotation shaft 453.

[0091] In the rotation of the chuck 45 about the rotation axis 453, the reference state is a state in which the orientations of the upper piece 450 and the lower piece 452 are parallel to the horizontal direction. In this reference state, the lower surface of the upper piece 450 abuts against the upper end of the push bolt 442.

[0092] In this reference state, the lower piece 452 is in its outermost position (most open) when it moves inward and outward. The tension spring 46 biases the upper piece 450 so that the chuck portion 45 is in the reference state.

[0093] When the push ring 440 rotates in one direction relative to the chuck portion 45 in this reference state and the push bolt 442 rises, the lower surface of the upper piece 450 is pushed up by the upper end of the rising push bolt 442. Then, when the upper end of the push bolt 442 further pushes up the lower surface of the upper piece 450 against the biasing force of the tension spring 46, the chuck portion 45 rotates around the rotation shaft 453.

[0094] During this movement, the upper piece 450 opens outward and the lower piece 452 closes inward in the inward and outward directions, centered on the rotation axis 453. When the lower piece 452 closes inward in this manner, the tip of the lower piece 452 supports from below the bottom of the workpiece fitted into the lower frame 410, allowing the lower piece 452 to hold the workpiece.

[0095] On the other hand, when the push ring 440 rotates in the other direction and the push bolt 442 descends, the upper end of the push bolt 442 gradually descends, and the rotated chuck part 45 returns to the standard orientation. When the push bolt 442 descends to the bottom, the chuck part 45 returns to the standard position.

[0096] In this structure, torque is generated in the worm portion 42 and the worm wheel 43 due to the driving force of one relatively small motor 41, and further, the three planetary gears 44 can be rotated together in the same direction in conjunction with the rotation of the one worm wheel 43. In other words, the three chuck portions 45 can be rotated in a coordinated manner, allowing the lower pieces 452 to grip or separate the workpiece.

[0097] That is, the three chucks 45 for gripping the workpiece can be driven efficiently and accurately by a simple combination of a relatively small and inexpensive motor 41, a worm portion 42, a worm wheel 43, and a planetary gear 44. Furthermore, the overall structure of the hand unit 4 can be made compact, and relatively small motors and reducers can be used in the movement mechanisms for driving it.

[0098] Furthermore, in this structure, by using the worm portion 42 and the worm wheel 43, these members will not rotate due to external forces such as vibrations. In other words, the chuck portion 45 is driven only by the driving force generated by the motor 41, and unintentional rotation of the chuck portion 45 due to the influence of external forces, etc., can be prevented.

[0099] As a result, even if the drive of the hand unit 4 stops when a power outage or other power supply problem occurs, the chuck portion 45 does not rotate and can maintain its grip on the workpiece, thereby reducing the risk of the workpiece falling, etc.

[0100] [Worm Wheel and Planetary Gears] Next, the gear structures of the worm wheel 43 and the planetary gears 44 will be described. As shown in Fig. 7(a) , in a plan view, the teeth 431 of the worm wheel 43 and the teeth 448 of the planetary gears 44 are positioned to mesh with each other in a region where they contact each other, and the planetary gears 44 also rotate in conjunction with the rotation of the worm wheel 43. Note that Fig. 7(a) shows only one planetary gear 44 for the sake of convenience of explanation.

[0101] 7(c), the direction in which the teeth 431 of the worm wheel 43 are formed is inclined at an angle of approximately 3.7 degrees (diagonally rising to the right in FIG. 7(c)) with respect to the axis (virtual central axis of rotation) of the worm wheel 43. In other words, the worm wheel 43 has the shape of a helical gear with its teeth formed at an angle.

[0102] As shown in FIG. 7(b), the end surface 432 of the tooth 431 is formed in a straight line such that the diameter of the worm wheel 43 at the upper end position of the tooth 431 increases downward along the Z-axis direction (the up-down direction in FIG. 7(c)).

[0103] 7(c), the direction in which the teeth 448 of the planetary gear 44 are formed is inclined at an angle of approximately 3.7 degrees (diagonally upward to the left in FIG. 7(c)) with respect to the axis (virtual central axis of rotation) of the planetary gear 44. The approximately 3.7-degree oblique direction of the teeth 448 is formed in the opposite direction to the oblique direction of the teeth 431 of the worm wheel 43.

[0104] As shown in FIG. 7(b), the end face 449 of the tooth 448 is formed in a straight line such that the diameter of the planet gear 44 at the upper end position of the tooth 448 increases downward along the Z-axis direction (the up-down direction in FIG. 7(c)).

[0105] By forming the teeth 431 of the worm wheel 43 and the teeth 448 of the planetary gear 44 in this shape, the gap at the position where the teeth 431 and 448 overlap most in the area where the teeth 431 and 448 mesh can be reduced, resulting in a structure that increases the efficiency of power transmission.

[0106] This allows the driving force generated by one motor 41 and one worm wheel 43 to be sufficient to rotate the three planetary gears 44 .

[0107] In addition, in the case of the teeth of a general worm wheel or planetary gear, as shown in Figure 8, the direction in which the teeth G1 are formed is parallel to the axis of the worm wheel or the like, and the end face G2 of the teeth G1 has a shape with a recessed center along the Z-axis direction.

[0108] 8, when the teeth of the worm wheel and the teeth of the planetary gears mesh, a large gap is generated, and it is expected that the power transmission efficiency will be insufficient. Therefore, in the present invention, it is preferable to adopt the shapes of the teeth 431 of the worm wheel 43 and the teeth 448 of the planetary gears 44.

[0109] [Z-Axis Movement Mechanism] Next, we will explain the structure of the Z-axis movement mechanism 3. As described above, the Z-axis movement mechanism 3 has the Z-axis drive unit 30 and the pull arm 31 (see FIG. 9(b)). In addition, the pan unit 3000, tilt unit 3010, and hand unit 4 are attached below the pull arm 31.

[0110] 9(a), the pull arm 31 has a box-shaped, nested outer cover 310 whose length changes stepwise along the Z-axis direction. As shown in FIG. 9(b), the Z-axis drive unit 30 is provided inside the outer cover 310.

[0111] 9(b) and 10(a) to 10(c), in order to clarify the internal structure of the pool arm 31, the outer cover 310 is shown by a dashed line to illustrate the internal structure.

[0112] Furthermore, the pan unit 3000, tilt unit 3010, and hand unit 4 can be raised and lowered integrally along the Z-axis direction by driving the Z-axis drive unit 30. At this time, the length of the outer cover 310 (pool arm 31) is configured to expand and contract in accordance with the raising and lowering operation of the hand unit 4 and the like (the winding and feeding operation of the Z-axis chain 304, which will be described later).

[0113] Also, as shown in Figures 10(a) to 10(c), the Z-axis drive unit 30 has a Z-axis motor 300, a Z-axis worm reducer 301, a drive sprocket 302, a driven sprocket 303, a Z-axis chain 304, a first movable pulley 305, a second movable pulley 306, a weight 307, and a base portion 308.

[0114] Here, Z-axis motor 300 is a member that generates a driving force for winding up or letting out Z-axis chain 304. Furthermore, Z-axis worm reducer 301 is a member to which the driving force of Z-axis motor 300 is transmitted and which generates torque. Although not shown, Z-axis worm reducer 301 is composed of a worm part and a worm wheel.

[0115] The drive sprocket 302 is a gear member that is connected to the Z-axis worm reducer 301, has a portion of the Z-axis chain 304 wound around its outer circumferential surface, and is responsible for winding or letting out the Z-axis chain 304. The driven sprocket 303 is a gear member that assists the drive sprocket 302 in winding or letting out the Z-axis chain 304.

[0116] In addition, the Z-axis chain 304 is a transmission member for raising and lowering the base part 308, and is a chain member whose length along the Z-axis direction changes when it is wound up or sent out via the driving force generated by the Z-axis motor 300.

[0117] In other words, the Z-axis chain 304 is wound up, shortening its length along the Z-axis direction, causing the hand unit 4 etc. to rise, and the Z-axis chain 304 is sent out, lengthening its length along the Z-axis direction, causing the hand unit 4 etc. to descend.

[0118] The first movable pulley 305 and the second movable pulley 306 are pulley members for reducing the force required to wind up the Z-axis chain 304, which is required to lift a member below the base 308. The weight 307 is a weight member for the second movable pulley 306.

[0119] By providing two movable pulleys, the first movable pulley 305 and the second movable pulley 306, the driving force required of the Z-axis motor 300 is reduced, making it possible to use a relatively small motor.

[0120] The base 308 is a member that connects the lower end of the pulley arm 31 to the pan unit 3000. The base 308 is a member that serves as a support base that rotatably supports the first movable pulley 305.

[0121] The Z-axis motor 300 referred to here is a component equivalent to the Z-axis motor in the claims of the present application. The Z-axis worm reducer 301 referred to here is a component equivalent to the Z-axis worm reducer in the claims of the present application, and the worm part and worm wheel constituting the Z-axis worm reducer 301 referred to here are components equivalent to the Z-axis worm part and Z-axis worm wheel in the claims of the present application.

[0122] The Z-axis chain 304 referred to here is a member that corresponds to the Z-axis chain portion in the claims. The first movable pulley 305 and the second movable pulley 306 referred to here are members that correspond to the movable pulleys in the claims. The base portion 308 referred to here is a member that corresponds to the base portion in the claims.

[0123] Furthermore, the ends 304a and 304b of the Z-axis chain 304 are fixed to fixed blocks 309 provided near the driven sprocket 302 (see FIGS. 10(a) and 10(b)).

[0124] In addition, the Z-axis chain 304 is partially wound around the outer circumferential surfaces of the first movable pulley 305, the driving sprocket 302, the driven sprocket 303, and the second movable pulley 306 between its end 304a and end 304b, and is structured so that its length along the Z-axis direction changes as it is wound up or let out via the driving sprocket 302 (see Figures 10(a) to 10(c)).

[0125] The structure of this Z-axis drive unit 30 is such that any deviation of the Z-axis chain 304 along the Z-axis direction caused by backlash (gap) in the Z-axis worm reducer 301 can be absorbed by the weight of the hand unit 4 and the like located below the base portion 308.

[0126] First, in this structure, there is a backlash (gap) in the direction of gear movement in the Z-axis worm reducer 301, and the presence of this backlash causes some deviation in the winding or unwinding movement of the Z-axis chain 304.

[0127] Therefore, in the structure of the Z-axis drive unit 30, the Z-axis chain 304 is arranged along the Z-axis direction (vertical direction), and a hand unit 4 or the like having a certain amount of weight is provided below the base part 308 that is raised and lowered by the Z-axis chain 304.

[0128] As a result, on the lower side of the movement range in the Z-axis direction, the weight of the hand unit 4 and the like makes it possible to move the positions of the base part 308 and the hand unit 4 and the like to the lowest position.

[0129] In other words, even if backlash exists, the hand unit 4, etc. can be positioned at the lowest position in the Z-axis direction due to its own weight, and this lowest position can be used as the starting point for movement in the Z-axis direction, ignoring the effects of backlash.

[0130] As a result, when raising and lowering the hand unit 4 along the Z-axis direction, the winding of the Z-axis chain 304 is controlled starting from the lowest position to adjust the distance of lift, thereby making it possible to ignore the effects of backlash and control movement along the Z-axis with high precision.

[0131] Furthermore, the Z-axis drive unit 30 can ensure the accuracy of movement in the Z-axis direction even while using components such as a relatively inexpensive motor, a worm reducer with backlash, and a chain.

[0132] [X-Axis Movement Mechanism and Y-Axis Movement Mechanism] Next, we will explain the X-axis movement mechanism 1 and the Y-axis movement mechanism 2 and their peripheral structure. As shown in Figure 11(a), the X-axis movement mechanism 1 has two X-axis H-beams 10 suspended between a pair of gantry sections G, an H-beam support section 11, and an X-axis chain 12.

[0133] Here, the X-axis H-beam 10 is a support portion for the Y-axis movement mechanism 2. Furthermore, the X-axis H-beam 10, together with the X-axis chain 12, forms the movement path along the X-axis of the Y-axis movement mechanism 2. Furthermore, the H-beam support portion 11 serves as an attachment portion for the X-axis chain 12 and also as a member that reinforces the X-axis H-beam 10.

[0134] In addition, the X-axis H-beam 10 has H-beam support parts 11 fixed to both ends in the X-axis direction (left and right direction), and one X-axis chain 12 is stretched between the two H-beam support parts 11 (see Figures 11(a) and 11(b)).

[0135] In addition, since the two X-axis H-beams 10 are arranged parallel to each other and the Y-axis moving mechanism 2 is suspended above them in a direction perpendicular to the X-axis H-beams 10, the Y-axis moving mechanism 2 can be stably supported.

[0136] 11A, a columnar hanging arm 70 is disposed on the front side and upper part of the Y-axis movement mechanism 2. This hanging arm 70 is a member that connects the Y-axis movement mechanism 2 and the pull arm 31.

[0137] 12, an arm pan unit 7 is provided below the approximate center of the hanging arm 70. The arm pan unit 7 is provided at the tip of a columnar Y-axis steel member 20 that constitutes the Y-axis movement mechanism 2.

[0138] The arm pan unit 7 is a drive mechanism that can adjust the longitudinal direction of the hanging arm 70 by rotating the direction between a direction parallel to the Y axis and a direction parallel to the X axis.

[0139] The hanging arm 70 referred to here is a member that corresponds to the support arm in the claims. The Y-axis steel material 20 referred to here is a member that corresponds to the Y-axis steel material in the claims. The arm pan unit 7 referred to here is a member that corresponds to the rotation drive mechanism in the claims.

[0140] The arm pan unit 7 also has a rotation drive unit 71 (see FIG. 12) that is made up of a motor 710, a belt 711, and a rotation shaft 712. The rotation shaft 712 fits into a hole (not shown) formed in a mounting plate 713.

[0141] Furthermore, two sandwiching plates 714 are arranged above the mounting plate 713, and the mounting plate 713 and the sandwiching plates 714 are connected by bolts 715 (see FIG. 12).

[0142] A hanging arm 70 is inserted between the mounting plate 713 and the sandwiching plate 714. The hanging arm 70 is disposed between a pair of protrusions (reference numerals omitted) formed on the upper surface of the mounting plate 713 along the longitudinal direction thereof, and the position of the hanging arm 70 in the short direction of the mounting plate 713 is determined (see FIG. 12 ).

[0143] In this rotation drive unit 71, the driving force of a motor 710 is transmitted via a belt 711 to rotate a rotation shaft 712. When the rotation shaft 712 rotates, the mounting plate 713 fitted thereto rotates integrally with the rotation shaft 712.

[0144] That is, by rotating the rotary shaft 712 and the mounting plate 713, the hanging arm 20 arranged on the mounting plate 712 can be rotated integrally with the rotary shaft 712. As a result, the pull arm 31 and the hand unit 4 positioned below it also rotate integrally, and the position of the hand unit 4 can be adjusted by rotating it horizontally.

[0145] 12, one Y-axis chain 21 is stretched on the lower side of the Y-axis steel material 20. This Y-axis chain 21 is a member that forms a movement path along the Y-axis together with the Y-axis steel material 20. Both ends of the Y-axis chain 21 are fixed to both ends of the Y-axis steel material 20, respectively.

[0146] Next, we will explain the structures of the X-axis moving unit 13 and the Y-axis moving unit 22. The X-axis moving unit 13 is a member that serves as a drive unit that moves along the X-axis chain 12. The Y-axis moving unit 22 is a member that serves as a drive unit that moves along the Y-axis chain 21.

[0147] The X-axis moving unit 13 and the Y-axis moving unit 22 are attached to one moving body plate 14 in directions perpendicular to each other (see FIGS. 13(a) and 13(b)).

[0148] The X-axis moving unit 13 and the Y-axis moving unit 22 are components that correspond to the X-axis moving section and the Y-axis moving section, respectively. The moving body plate 14 is a component that corresponds to the substrate plate.

[0149] In addition, a side frame portion 23 is provided on the upper portion of the movable main body plate 14 to enable the movable main body plate 14 to move along the Y-axis steel material 12 (see FIG. 13(a)). The side frame portion 23 extends upward from the movable main body plate 14, and a movement roller 230 is provided at its upper end.

[0150] This moving roller is rotatably fitted into the upper part of the Y-axis steel material 12, so that when the Y-axis moving unit 22 is driven and moves along the Y-axis chain 21, the moving main body plate 14 and side frame portion 23 can be moved smoothly along the Y-axis steel material 12.

[0151] The side frame portion 23 and the moving roller 230 are members that correspond to the Y-axis fitting portion in the claims of the present application.

[0152] The X-axis moving unit 13 and the Y-axis moving unit 22 have a common structure. Here, the structure will be explained using the X-axis moving unit 13.

[0153] As shown in FIG. 14( b ), the X-axis moving unit 13 has a motor 130 , a reducer 131 , a driving sprocket 132 , and a driven sprocket 133 .

[0154] In this X-axis moving unit 13, some of the gears formed on the outer surface of the drive sprocket 132 fit into multiple holes (not shown) formed in the X-axis chain 12, and the gears of the drive sprocket 132 rotate while meshing with these holes, thereby causing the X-axis moving unit 13 to move along the X-axis chain 12.

[0155] The motor 130 is a member that generates a driving force that rotates the drive sprocket 132, and the reducer 131 is a reducer to which the driving force of the motor 130 is transmitted and which generates torque. The reducer 131 is a reducer with a Harmonic Drive (registered trademark) mechanism.

[0156] The two driven sprockets 133 are rotatably arranged on either side of the drive sprocket 132. The driven sprocket 133 is provided to maximize the number of teeth that mesh with the drive sprocket 132 on the X-axis chain 12, and this structure can prevent tooth jumping due to shocks during running, etc. (see FIG. 14(a)).

[0157] The Y-axis moving unit 22 also has a structure similar to that of the X-axis moving unit 13, and is configured such that a drive sprocket (reference number omitted) in the Y-axis moving unit 22 rotates relative to the Y-axis chain 21, causing the Y-axis moving unit 22 to move along the Y-axis chain 21. A detailed description of the structure of the Y-axis moving unit 22 will be omitted.

[0158] [Position Recognition by Camera Sensor and Movement Control Based on Coordinate Information] Next, the position recognition of the workpiece by the camera sensor 6 and the movement control of the hand unit 4 based on coordinate information will be described.

[0159] First, the camera sensor 6 has an imaging unit and an optical cross section measurement laser (not shown). The imaging unit is a part that recognizes the outer shape of a workpiece positioned within the imaging range and markers attached to the workpiece.

[0160] The imaging unit referred to here corresponds to the imaging means in the claims, and the optical cross section measuring laser referred to here corresponds to the cross section measuring means in the claims.

[0161] In addition, the optical cross section measurement laser is a shape measurement sensor that irradiates infrared light onto a workpiece within the imaging range of the imaging unit, measures the unevenness data (cross section shape) of the workpiece's outer shape, and obtains theoretical workpiece center position information, which is information on the estimated center position of the workpiece.

[0162] The theoretical workpiece center position information acquired here is used to align the chuck portion 45 of the hand unit 4 with the workpiece to be gripped. Note that the theoretical workpiece center position information here corresponds to the estimated center position of the workpiece in the claims of this application.

[0163] In addition, the optical cross-section measurement laser measures the cross-sectional shape of a workpiece by irradiating the workpiece with infrared light in two mutually perpendicular directions in a planar view and scanning the workpiece surface (scanning in the X and Y directions based on the workpiece).

[0164] Furthermore, theoretical workpiece center position information can be obtained based on the measured cross-sectional shape of the workpiece and preset information on the shape of the workpiece.

[0165] The imaging unit and the optical cross section measuring laser in the camera sensor 6 are controlled by a position recognition CPU provided in the hand unit 4. The position recognition CPU here corresponds to the position recognition control unit in the claims of the present application.

[0166] Here, the position recognition CPU pre-records the shape of the workpiece to be grasped by the hand unit 4, and is configured to be able to recognize the workpiece from its external shape when the workpiece is imaged by the imaging unit.

[0167] The marker attached to the workpiece is identification information that serves as a guide for checking the horizontal rotation direction of the target workpiece. For example, a marker is a line of a certain length attached to the same position in the same direction on multiple workpieces of the same shape. The marker can also be attached to the workpiece with a pen or the like.

[0168] Here, it is assumed that the workers do not place the workpieces in the workpiece placement area provided around the processing device B in a lined up state with the workpieces oriented in the same direction, but place the workpieces haphazardly within the range of the workpiece placement area. In other words, the rotational directions of the individual workpieces in the horizontal direction may become irregular within the workpiece placement area.

[0169] Therefore, by placing a marker at a specific position on the workpiece and recognizing it with the imaging unit, it is possible to control the direction of horizontal rotation of the hand unit 4 so that the chuck portion 45 of the hand unit 4 is oriented in a way that allows it to grasp the workpiece.

[0170] The movement of the hand unit 4 is controlled by a coordinate movement CPU (not shown) provided on the above-mentioned moving body plate 14. That is, the movement of the hand unit 4 in the X-axis direction, Y-axis direction, and Z-axis direction via the X-axis movement mechanism 1, Y-axis movement mechanism 2, and Z-axis movement mechanism 3 is controlled by the coordinate movement CPU.

[0171] The coordinate movement CPU also controls the movement and adjustment of the direction of the hand unit 4 via the rotation drive unit 71, pan unit 3000, and tilt unit 3010 described above.

[0172] The movement of the hand unit 4 by this coordinate movement CPU is controlled based on coordinate position information of three axes, namely, the X-axis, Y-axis, and Z-axis directions (hereinafter referred to as "coordinate position information").

[0173] That is, the position of the workpiece placement section and the position of the processing chuck section of the processing device B, which will be the placement position and destination of the workpiece, are set in advance using coordinate position information and recorded in the CPU for coordinate movement, so that the hand unit 4 can be moved to the target position.

[0174] Furthermore, in the present invention, the movement of the hand unit 4 by the coordinate movement CPU and the recognition of the position of the workpiece by the camera sensor 6 described above can be combined to transport the workpiece by the hand unit 4.

[0175] An example of the flow of workpiece transport by the transport mechanism A will be described below.

[0176] [Flow of gripping a workpiece] First, a flow will be described in which the chuck portion 45 of the hand unit 4 grips a workpiece at a target position from a state in which the chuck portion 45 does not grip a workpiece. The target position here is, for example, the position of a plurality of workpiece placement portions provided around the processing device B or the position of the processing chuck portion of the processing device B.

[0177] The plurality of workpiece placement sections may include a place where a workpiece before processing is placed, a place where a workpiece after processing by the processing device B is placed, and the like.

[0178] First, the hand unit 4 is moved toward the workpiece placement section on which the unmachined workpiece is placed. The hand unit 4 moves to the position of the workpiece placement section according to the coordinate position information, based on the control of the coordinate movement CPU.

[0179] Furthermore, when the hand unit 4 reaches the position of the coordinate position information of the workpiece placement section, the camera sensor 6 captures an image using the imaging section. By capturing an image of the workpiece using this imaging section, the outer shape of the workpiece placed on the workpiece placement section and the markers attached to the workpiece are recognized.

[0180] When the position recognition CPU recognizes the preset workpiece shape and markers, the workpiece is scanned with infrared light by the optical cross section measurement laser, and theoretical workpiece center position information is obtained from the cross section shape of the workpiece.

[0181] Next, the position recognition CPU transmits the coordinate position information of the position of the chuck portion 45 of the hand unit 4 and the position of the theoretical workpiece center position information of the workpiece, as well as the position and orientation information of the marker, to the coordinate movement CPU.

[0182] In addition, based on the received position information, etc., the coordinate movement CPU performs a correction operation to align the position of the hand unit 4 with the workpiece so that the chuck portion 45 is in a position and rotated in a horizontal direction that allows it to grasp the workpiece.

[0183] The operations up to this point enable the chuck portion 45 of the hand unit 4 to be positioned within a few millimeters of the workpiece. Furthermore, the chucking operation when gripping the workpiece with the chuck portion 45 is performed automatically by the chuck portion 45 based on information obtained by recognizing the appearance of the workpiece using the imaging unit and by recognizing the angle based on the positions of the markers. Furthermore, a mode can also be adopted in which the chucking operation is performed visually by an operator via a controller (not shown) that can operate the hand unit 4.

[0184] The controller here may be, for example, a joystick or the like, and may be provided in the hand unit 4. Operating the hand unit 4 via this controller drives the motor 41, and the worm wheel 43 and the three planetary gears 44 rotate based on the driving force thereof, thereby opening and closing the chuck portion 45.

[0185] When the workpiece attached to the chuck portion of the processing device B is gripped by the hand unit 4, the same flow as described above is carried out.

[0186] [Flow when transporting a workpiece to a target position] Furthermore, when the chuck portion 45 of the hand unit 4 grips the workpiece and moves to the target position to which the workpiece is to be transported, the hand unit 4 moves to the position of the target coordinate position information based on the control of the coordinate movement CPU.

[0187] For example, the gripped workpiece is transported to the position of a workpiece placement section where the processed workpiece will be placed, or to the position of a chuck section of the processing device B.

[0188] Furthermore, when the hand unit 4 reaches the position of the workpiece placement section where the processed workpiece is placed, the hand unit 4 is driven through the control of the main control section 5, and the chuck section 45 separates the workpiece so that the workpiece can be placed at that position.

[0189] Furthermore, when the hand unit 4 holding the workpiece moves to the position of the chuck portion of the processing device B, the worker operates the controller while visually checking the position, to chuck the workpiece into the chuck portion of the processing device B and separate the workpiece from the hand unit 4, in the same manner as described above.

[0190] As described above, the hand unit 4 of the transport mechanism A roughly moves to the position of the target coordinate position information via the X-axis movement mechanism 1, the Y-axis movement mechanism 2, the Z-axis movement mechanism 3, etc., based on the control of the coordinate movement CPU.

[0191] Then, the positional relationship between the chuck portion 45 and the workpiece is recognized via the camera sensor 6, and the hand unit 4 is moved under the control of the coordinate movement CPU to a position near the workpiece where the chuck portion 45 can once again grasp the workpiece.

[0192] In other words, the conveying mechanism A recognizes the position of the workpiece via the camera sensor 6 and then aligns it, so unlike conventional conveying mechanisms that use components such as ball screws, it does not require high-precision movement, and deviations in the order of millimeters cannot be tolerated.

[0193] This makes it possible to use components with relatively low movement accuracy, such as chains and H-beams, for components that move the X-axis movement mechanism 1. Also, as for the camera sensor 6, it is sufficient if it can recognize the outline of the workpiece and the markers, so an inexpensive camera that captures monochrome images can be used.

[0194] Furthermore, the transport mechanism A to which the present invention is applied can be installed in a limited working space such as a factory by using the space above the processing device B, and can transport workpieces.

[0195] Furthermore, the transport mechanism A can be constructed using relatively inexpensive components for the various components constituting the transport mechanism, while still being capable of transporting workpieces stably.

[0196] As described above, a conveying mechanism to which the present invention is applied can be installed in a work space with limited space in a factory or the like where workpieces are processed using machine tools, and can transport workpieces between the workpiece placement area within the machine tool and the area surrounding the machine tool, and can be constructed using relatively inexpensive components.

[0197] A Conveying mechanism B Processing device B1 Working space B2 Drive door G Gantry section 1 X-axis moving mechanism 10 X-axis H-beam 11 H-beam support section 12 X-axis chain 13 X-axis moving unit 130 Motor 131 Reducer 132 Driving sprocket 133 Driven sprocket 14 Moving body plate 2 Y-axis moving mechanism 20 Y-axis steel material 21 Y-axis chain 22 Y-axis moving unit 23 Side frame section 230 Moving roller 3 Z-axis moving mechanism 30 Z-axis drive unit 300 Z-axis motor 301 Z-axis worm reducer 302 Driving sprocket 303 Driving sprocket 304 Z-axis chain 304a End 304b End 305 First moving pulley 306 Second moving pulley 307 Weight 308 Base part 309 Fixed block 31 Pool arm 310 Outer cover 3000 Pan unit 3010 Tilt unit 4 Hand unit 40 Main frame 41 Motor 42 Worm part 43 Worm wheel 430 Convex part 431 Teeth 432 End face 44 Planetary gear 440 Push ring 441 Thread groove 442 Push bolt 443 Lower side (of push bolt) 444 Upper side (of push bolt) 445 Thread groove 446 Guide part 447 Square hole 448 Teeth 449 End face 45 Chuck part 450 Upper piece 451 Main body 452 Lower piece 453 Rotating shaft 46 Tension spring 47 Gear roller 470 Gear roller shaft 471 Bearing 472 Drum-shaped roller 473 V-shaped groove 400 Upper frame 401 Through-hole 410 Lower frame 411 Recess 412 Recess 5 Main control unit6 Camera sensor 7 Arm pan unit 70 Hanging arm 71 Rotation drive unit 710 Motor 711 Belt 712 Rotation shaft 713 Mounting plate 714 Clamping plate 715 Bolt G1 Teeth G2 End face

Claims

1. A transport mechanism for transporting a workpiece of a predetermined weight, which is to be machined by a predetermined machine tool, between a workpiece temporary placement area and a mounting area within the predetermined machine tool, comprising: a main frame which is a plate-like body with a predetermined through-hole formed therein and has a workpiece fitting portion formed on its bottom side for fitting with the workpiece; a motor attached to the top surface of the main frame as a drive source; a worm portion which rotates based on the driving force of the motor; a ring-shaped worm wheel which transmits power by meshing with the worm portion; a plurality of planetary gears which are arranged on the outside of the worm wheel and transmit power by meshing with the worm wheel; a plurality of gear rollers which are rotatably attached to the top surface of the main frame and are arranged inside the worm wheel to support the worm wheel; and a chuck portion which is paired with the planetary gear and which grips or separates the workpiece fitted in the workpiece fitting portion as the planetary gear rotates; a camera sensor attached to the top surface of the main frame at a position corresponding to the predetermined through-hole, and having an imaging means on the bottom surface side; a Z-axis drive mechanism which is a columnar body arranged parallel to the Z-axis direction which is a vertical direction, with the hand unit disposed below it and capable of moving the hand unit up and down along the Z-axis direction; an X-axis drive mechanism which allows the Z-axis drive mechanism to move along the X-axis direction which is a direction along the edge of the predetermined machine tool and which is a direction perpendicular to the Z-axis direction, and has an X-axis movement path provided above the predetermined machine tool; and a Y-axis drive mechanism which allows the Z-axis drive mechanism to move along the Y-axis direction which is a direction perpendicular to both the Z-axis direction and the X-axis direction, and has a Y-axis movement path provided above the X-axis movement path. A transport mechanism comprising a rotation drive mechanism that is provided above the Y-axis drive mechanism, connects the Y-axis drive mechanism to the Z-axis drive mechanism, has a support arm that supports the Z-axis drive mechanism, and is configured so that the longitudinal direction of the support arm can be rotated between a direction parallel to the Y-axis direction and a direction perpendicular to the Y-axis direction.

2. The conveying mechanism according to claim 1, wherein the camera sensor has a cross-section measuring means for acquiring unevenness data of the workpiece via an infrared laser, and is capable of recognizing the predetermined outer shape of the workpiece and the positions of markers attached to the workpiece via the imaging means, and estimates the estimated center position of the workpiece based on the unevenness data acquired by the cross-section measuring means.

3. A transport mechanism according to claim 2, wherein the hand unit is provided with a position recognition control section that controls the driving of the camera sensor and controls the recognition process of the position of the workpiece.

4. A conveying mechanism as described in claim 1 or claim 2, wherein the gear roller has a V-shaped groove formed on its outer circumferential surface with a recess in the approximate center along the Z-axis direction, and the worm wheel has an inner circumferential surface formed with a convex portion that fits into the V-shaped groove along the Z-axis direction.

5. A conveying mechanism as claimed in claim 1 or claim 2, wherein the teeth of the worm wheel are formed, in a front view, so as to be inclined at a certain angle in one direction relative to the axis of the worm wheel, and a linear taper is provided on the outer circumferential surface of the teeth along the Z-axis direction so that the diameter of the worm wheel increases from the top surface side to the bottom surface side, and the teeth of the planetary gears are formed, in a front view, so as to be inclined at a certain angle in the opposite direction to the one direction relative to the axis of the worm wheel, and a linear taper is provided on the outer circumferential surface of the teeth along the Z-axis direction so that the diameter of the planetary gear increases from the top surface side to the bottom surface side.

6. A conveying mechanism as described in claim 1 or claim 2, comprising: a ring base, which is a cylindrical body attached to the planetary gear inside the planetary gear, with a first screw groove formed on the inner peripheral surface of a hole, and which rotates together with the planetary gear; and a columnar body, part of which is inserted into the hole of the ring base, with a second screw groove formed on its outer peripheral surface that abuts against the inner peripheral surface of the hole, which engages with the first screw groove, and whose rotation about its axis is restricted, and which rises and falls in the Z-axis direction as the ring base rotates; and the chuck portion is approximately U-shaped and is rotatably supported on the main frame, and the bottom surface of its protruding upper side is pressed by the upper end of the rising lift bolt, causing the chuck portion to rotate, and the protruding lower portion of the chuck portion grips the workpiece fitted in the workpiece fitting portion.

7. The Z-axis drive mechanism comprises: a Z-axis motor serving as a drive source; a Z-axis worm reducer consisting of a Z-axis worm section that rotates based on the drive force of the Z-axis motor; and a Z-axis worm reducer consisting of a Z-axis worm wheel that transmits power by meshing with the Z-axis worm section; a Z-axis chain section that is attached to the Z-axis worm wheel and can be wound up and let out along the Z-axis direction as the Z-axis worm wheel rotates; a movable pulley that is attached to the Z-axis chain section and rises and falls as the Z-axis chain section is wound up and let out; and a base section that is positioned below the movable pulley and rotatably supports the movable pulley, and has the hand unit positioned below it, and the weight including the weight of the hand unit allows the transport mechanism to be positioned at the lowest position within the lifting range of the hand unit in the Z-axis direction.

8. The X-axis drive mechanism is composed of a base plate that is the main body of the moving body, an X-axis motor that is the drive source, an X-axis reducer that outputs torque from the drive force of the X-axis motor, and an X-axis sprocket that rotates with the output torque from the X-axis reducer, and has an X-axis moving part attached to the base plate, and the X-axis moving path is composed of X-axis steel members made of two steel members parallel to the X-axis direction, and an X-axis chain member that is a chain member with both ends fixed and parallel to the X-axis direction and stretched between the two steel members, and the X-axis sprocket is fitted onto the top of the X-axis chain member and rotates, so that the X-axis moving part and the base plate move along the X-axis steel members and the X-axis chain member.

9. The Y-axis drive mechanism is composed of a Y-axis motor as a drive source, a Y-axis reducer that outputs torque from the drive force of the Y-axis motor, and a Y-axis sprocket that rotates with the output torque from the Y-axis reducer, and has a Y-axis moving part attached to the base plate, and the Y-axis moving path is composed of a Y-axis steel material that is a single piece of steel that is arranged above the base plate and oriented perpendicular to the X-axis steel material, a Y-axis fitting part that is provided on the top of the base plate and attached to the Y-axis steel material and is movable along the Y-axis steel material, and a Y-axis chain part that is a chain member with both ends fixed below both ends of the Y-axis steel material and is stretched parallel to the Y-axis direction, and the Y-axis sprocket fits onto the top of the Y-axis chain part and rotates, so that the Y-axis moving part and the base plate move along the Y-axis steel material and the Y-axis chain part.

10. A conveying mechanism as described in claim 1 or claim 2, wherein the Y-axis drive mechanism is capable of moving the Z-axis drive mechanism along the Y-axis direction to a position beyond the edge of the specified machine tool.

11. A transport mechanism as described in claim 1 or claim 2, further comprising a pan-tilt mechanism that is disposed between the Z-axis movement mechanism and the hand unit, connects the Z-axis movement mechanism and the hand unit, and enables the hand unit to rotate in a horizontal direction parallel to the X-axis direction and the Y-axis direction, and also enables the hand unit to rotate in the Z-axis direction.

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