Workpiece suction unit and workpiece transport device

Abstract

To provide a work-piece suction unit that does not require air supply for suction of a work-piece, and a work-piece carrier that uses the work-piece suction unit in carrying the work-piece.SOLUTION: A work-piece suction unit is allowed to bring a cap member 7 provided on a table member 13 set up for a rotor 2 into / out of contact with an opening end of an air passage 4 for communication with an interior of a suction pad 3 by a press action of a knock rod 11 of a double-knock mechanism and switch over the enclosure state in the suction pad against which a work-piece B, an object of suction, is pushed against, to suck or release the work-piece B by a pressure difference generated within the suction pad 3.SELECTED DRAWING: Figure 1

Description

[Technical Field]

[0001] The present invention relates to a workpiece suction unit that can suck and release a workpiece such as a filled container without using suction air, and a workpiece transport device that transports the workpiece using the workpiece suction unit. [Background technology]

[0002] Conventionally, a work transport device has been used that includes a work suction unit that adsorbs a workpiece onto an adsorption pad, and transports the workpiece to a desired position while held by the work suction unit, and performs delivery and allocation (see Patent Documents 1 and 2).

[0003] For example, the workpiece transport device disclosed in Patent Document 1 is a device that includes a rotating body having a plurality of holding means for holding containers as workpieces, and label application mechanisms arranged at two stations on the rotating body, and transports the containers so that labels are applied to them, but a first transfer mechanism is provided adjacent to the rotating body, and a supply conveyor and robot for transporting the containers are also provided adjacent to that.The robot is configured to suck and hold an overturned container transported by the supply conveyor, then raise it to an upright position and transfer it to the holding means of the first transfer mechanism in a transfer area.

[0004] The robot used in the workpiece transport device is a well-known six-axis robot, with a hand that can rotate horizontally and vertically, and at the tip of the hand is a support frame that constitutes a workpiece suction unit, and a suction pad that is attached to the support frame, and an air hose that is connected in communication with a suction pump is connected to the suction pad, so that the workpiece is sucked and held by supplying negative pressure to the suction pad, and on the other hand, the held state of the workpiece is released by stopping the supply of negative pressure to the suction pad, and this type of industrial robot is often used. [Prior art documents] [Patent documents]

[0005] [Patent Document 1] Japanese Patent Application Laid-Open No. 2007-008641 [Patent Document 2] WO2018 / 078780 publication Summary of the Invention [Problem to be solved by the invention]

[0006] However, a workpiece suction unit that uses negative pressure supplied to a suction pad via an air hose to suction a workpiece requires the air hose to be routed.

[0007] The workpiece suction unit shown in the aforementioned Patent Document 1 has four suction pads arranged on a hand with their suction surfaces on the same plane, and is configured so that the robot hand follows the body of an overturned container transported by a supply conveyor, while the hand with the suction pads facing downward rotates horizontally according to the orientation of the container, aligning the orientation so that the head of the container faces the same direction and holding it by suction. In particular, when following the hand or rotating it horizontally in this way, the hand also needs to stretch or wrap the air hoses connected to each suction pad, making handling cumbersome.

[0008] Furthermore, the workpiece transport device that transports the adsorbed workpiece is not necessarily limited to a robot with a hand as described above, and the transport range of the workpiece is not limited to the rotation range of the robot's main body and the horizontal and vertical movement range of the hand as described above. For example, as shown in Patent Document 2, a workpiece transport device has been proposed in which a workpiece suction unit is provided with a workpiece suction section made of a suction pad that is movable up and down below a running platform that moves on a running rail, and compressed air is supplied to an ejector to create a vacuum so that the workpiece is adsorbed onto the suction pad, and in this state the workpiece suction unit is transported along the running rail over a linear distance that would be difficult to transport using the robot's hand.

[0009] Even under driving conditions such as a long conveying distance or a complex conveying route, it would be highly desirable if quiet and stable suction and conveyance of workpieces could be performed without the need for air supply via an air hose.

[0010] The present invention has been made in consideration of these problems, and aims to provide a workpiece suction unit that does not require the supply of air to suction a workpiece, and a workpiece transport device that transports a workpiece using the workpiece suction unit. [Means for solving the problem]

[0011] In order to achieve the above-mentioned object, the workpiece suction unit of the present invention comprises a housing, a suction pad arranged on the workpiece suction surface of the housing, an air passage that connects the space inside the suction pad to the back side of the workpiece suction surface, and air passage opening and closing means that opens and closes the open end of the air passage, and the air passage opening and closing means comprises a cam body, a knock rod, and a rotor that constitute a double knock mechanism, a table member on which a cap member is arranged opposite to the open end of the air passage and is arranged so as to be slidable and rotatable relative to the rotor, and a biasing member that biases the table member so as to normally bring the cap member into contact with the open end of the air passage to close the air passage, and is configured so that the open and closed state of the open end of the air passage by the cap member arranged on the table member can be switched by raising and lowering the rotor through the pressing operation of the knock rod.

[0012] The cam body of the double knock mechanism has a plurality of grooves formed in the large-diameter cylindrical portion at the axial tip of the base shaft, the grooves extending in the axial direction, and two series of mountain-shaped cam teeth formed at the base end between the grooves of the large-diameter cylindrical portion. The knock rod is attached to the outer periphery of the large-diameter cylindrical portion of the cam body in the axial direction. movableand the rotor is fitted into a cylindrical hollow portion of the rotor, in which the cam body and the knock rod are disposed, and has a plurality of protrusions formed on the inner peripheral surface of the base end thereof to fit into the grooves, and the tip of each protrusion is formed as an inclined portion to engage with the cam teeth of the cam body and the cam teeth of the knock rod.

[0013] The knock rod is characterized in that the operating part at the tip protrudes outward from the workpiece suction surface of the housing, and is arranged so that it can be raised and lowered by a pressing operation that presses the workpiece to be sucked against the suction pad.

[0014] The housing is characterized in that a stopper is disposed on the housing to regulate the position of the rotor biased by the biasing member via the table member.

[0015] According to the workpiece suction unit of the present invention, when the workpiece to be sucked is pressed against the suction pad, the knock rod is pressed against the suction pad together with the workpiece, and by raising and lowering the rotor by pressing the knock rod, the open end of the air passage is opened and closed by the cap member, and the workpiece can be sucked and released by the differential pressure generated within the suction pad against which the workpiece is pressed.

[0016] The workpiece transport device of the present invention is characterized in that the above-mentioned workpiece suction unit is arranged so as to be able to circulate along a workpiece transport path to which a workpiece receiving position and a workpiece carrying-out position are assigned.

[0017] According to the workpiece transport device of the present invention, it is possible to perform suction transport of the workpiece quietly and stably, regardless of the distance and positional relationship between the workpiece receiving position and the workpiece unloading position, without requiring the supply of air via an air hose.

[0018] A robot that presses the workpiece against the suction pad and / or the knock rod is disposed at the workpiece receiving position and / or the workpiece carrying-out position.

[0019] According to the workpiece transport device of the present invention, the workpiece can be easily transported by suction through control without relying on human labor. [Effects of the Invention]

[0020] In this way, with the workpiece suction unit of the present invention, it is possible to suck and release a workpiece by utilizing the differential pressure generated within the suction pad by pressing the knock rods of the double knock mechanism, without requiring the supply of air via an air hose. And, with the workpiece transport device of the present invention using this workpiece suction unit, it is possible to stably suck and transport a workpiece, regardless of the length of the transport distance or the simplicity or complexity of the route. [Brief explanation of the drawings]

[0021] [Figure 1] FIG. 1 is a vertical cross-sectional view illustrating a configuration of a main part of an embodiment of a workpiece suction unit according to the present invention. [Figure 2] FIG. 1 is an exploded view of a cam body, a knock rod, and a rotor that constitute the double knock mechanism of the workpiece suction unit of this embodiment. [Figure 3] 1 is an assembly diagram of a cam body, a knock rod, and a rotor that constitute the double knock mechanism of the workpiece suction unit of this embodiment. [Figure 4] FIG. 10 is an explanatory diagram showing a state when a knock rod is pressed to adsorb a workpiece in the workpiece adsorption unit of this embodiment. [Figure 5] FIG. 10 is an explanatory diagram showing a state when a pressure difference is generated to adsorb a workpiece in the workpiece suction unit of this embodiment. [Figure 6] FIG. 10 is an explanatory diagram showing a state when a knock rod is pressed to release the suction of the workpiece in the workpiece suction unit of this embodiment. [Figure 7] FIG. 10 is an explanatory diagram showing a state when the differential pressure is released to adsorb the workpiece with the workpiece suction unit of this embodiment. [Figure 8] FIG. 1 is a partial cross-sectional view illustrating a main configuration of an embodiment of a workpiece transport device according to the present invention. [Figure 9]FIG. 10 is a partial cross-sectional view illustrating the posture of the workpiece suction unit and the slider at the workpiece receiving position of the workpiece transport device according to the present invention. DETAILED DESCRIPTION OF THE INVENTION

[0022] First, an embodiment of a workpiece suction unit 1 according to the invention will be described with reference to FIGS.

[0023] The workpiece suction unit 1 of this embodiment is for suction-holding a container B filled with dishwashing detergent or the like as a workpiece.

[0024] 1, the workpiece suction unit 1 of this embodiment has a housing 2 having a substantially rectangular parallelepiped outer shape, and two suction pads 3 for suctioning a container B are arranged on one surface (the top surface in the figure) of the housing 2 in the axial direction of the container B to be sucked, at a distance that allows both to suck the body of the container B (hereinafter, the surface of the housing on which these suction pads 3 are arranged will be described as the workpiece suction surface). Note that in this embodiment, a multi-stage bellows pad with a diameter of 30 mm is used as the suction pad 3 in consideration of the thickness and weight of the body of the container B, but the type and size of the suction pads 3 used are not limited to this, and the number and arrangement positions of the suction pads can also be changed according to the workpiece.

[0025] An air passage 4 is formed within the thickness of the material that constitutes the workpiece suction surface of the housing 2, connecting the space within the pad formed by the bellows of each suction pad 3 to the back side of the workpiece suction surface.

[0026] The workpiece suction unit 1 of this embodiment is equipped with an air passage opening / closing means 8 that opens and closes the open end of the air passage 4 that opens into the housing 2.

[0027] In this embodiment, the air passage opening / closing means 8 is composed of a cam body 10, a knock rod 11, and a rotor 12 that constitute a so-called double knock mechanism 9, a table member 13 that is arranged so as to be slidable and rotatable relative to the rotor 12, and a biasing member (14) that biases the table member 13 toward the workpiece suction surface.

[0028] As shown in Figures 2 and 3, the cam body 10 of the double knock mechanism 9 has a large-diameter cylindrical portion 10b at the axial tip of the base shaft 10a, on which multiple grooves 10c extending in the axial direction are formed, and two series of mountain-shaped cam teeth 10d are formed at the base end between each groove 10c of the large-diameter cylindrical portion 10b.

[0029] The knock rod 11 is fitted onto the outer periphery of the large-diameter cylindrical portion 10b of the cam body 10, is connected by a screw 18 that passes through the elongated hole 11c and the screw hole 10f of the cam body 10, and has a mountain-shaped cam tooth 11a formed at its base end. The operating portion 11b at the tip protrudes outward from the workpiece suction surface of the housing 2, and the screw 18 slides within the elongated hole 11c when the body of the container B to be sucked is pressed against the suction pad 3, so that the knock rod 11 can move a predetermined distance. In this embodiment, the knock rod 11 is arranged between the two suction pads 3, 3 so that the operating portion 11b at the tip protrudes.

[0030] In this embodiment, the rotor 12 is formed in a cylindrical shape having a cylindrical hollow portion 12a in which the cam body 10 and the knock bar 11 are disposed. A plurality of protrusions 12b that fit into the grooves 10c are formed on the inner peripheral surface of the base end of the hollow portion 12a, and the tip of each protrusion 12b is formed as an inclined portion 12c that engages with the cam teeth 10d of the cam body 10 and the cam teeth 11a of the knock bar 11.

[0031] The table member 13 is arranged such that the annular portion 13a is fitted onto the rotor 12 via a bearing 15 so as to be freely slidable and rotatable, and cap members 7 made of a resin material such as nitrile or silicone are arranged on the table portion 13b extending outward from the annular portion 13a so as to face each opening end of the air passage 4.

[0032] In this embodiment, the biasing member (14) is made up of a coil spring 14, and is disposed between the table portion 13b of the table member 13 and the inner bottom surface of the housing 2, and is disposed so as to bias the table member 13 so as to normally abut the cap member 7 against the open end of the air passage 4 to close the air passage 4. In other words, in this embodiment, the biasing force of the coil spring 14 and the fact that the position of the coil spring 14 is fixed by the coil spring locking portions 16 provided on the back surface of the table portion 13b and the inner bottom surface of the housing 2, respectively, means that the rotation of the rotor 12 is not hindered, and the rotation of the table member 13 itself is restricted.

[0033] Further, the housing 2 is provided with a stopper 17 for regulating the position of the rotor 12 biased by the coil spring 14 via the table member 13.

[0034] The air passage opening / closing means 8 is configured to be able to switch between the open and closed states of the open end of the air passage 4 by the cap member 7 disposed on the table member 13, by sliding the rotor 12 when the knock rod 11 is pressed.

[0035] Although the double knock mechanism is a known mechanism, the operation of the double knock mechanism in the air passage opening and closing means 8 of the workpiece suction unit 1 of this embodiment will be briefly described here. When knock rod 11 is pressed, cam tooth 11a at the base end of knock rod 11 comes into contact with inclined portion 12c at the tip of protrusion 12b of rotor 2, and rotor 12 moves within groove 10c of cam body 10 against the bias of coil spring 14, with protrusion 12b aligned with groove 10c, and moves toward the base end in the axial direction (movement in this direction is called "downward," and movement in the opposite direction is called "upward").

[0036] When the knock rod 11 and rotor 2 descend a predetermined distance, the protrusion 12b disengages from the groove 10c, and the biasing force of the coil spring 14 becomes stronger than the pressing force of the knock rod 11, the knock rod 11 and rotor 2 ascend. At this time, with the cam teeth 11a of the knock rod 11 and the cam teeth 10c of the cam body 10 positioned at the same level, the inclined portion 12c of the rotor 2 moves from the cam surface of the cam teeth 11a of the knock rod 11 to the cam surface of the cam teeth 10d of the cam body 10, and then moves into the double-angled tooth-shaped valley portion 10e of the cam body 10, causing the rotor 2 to rotate. When the inclined portion 12c is positioned in the valley portion 10e, the rotor 2 and knock rod 11 stop ascending and remain at that height. In this embodiment, this state is utilized when suctioning the container B.

[0037] Then, by pressing the knock rod 11 again, the cam tooth 11a at the base end of the knock rod 11 comes into contact with the inclined portion 12c located in the valley portion 10e, causing the rotor 2 to temporarily descend toward the base end in the axial direction while resisting the bias of the coil spring 14. As a result, the inclined portion 12c leaves the valley portion 10e.

[0038] Thereafter, when the biasing force of the coil spring 14 becomes greater than the pressing force of the knock rod 11, the rotor 12 and knock rod 11 rise again toward the axial tip. At this time, the inclined portion 12c of the rotor 12 is guided from the cam surface of the cam teeth 11a of the knock rod 11 to the cam surface of the cam blades 11a of the cam body 10, and is further guided into each groove 10c formed in the rotational direction. At this time, the rotor 2 rotates, and the positional and engagement relationship between the knock rod 11 and the rotor 12 returns to its original state. In this embodiment, this state is used before and after the container B is attracted.

[0039] The system for suctioning and releasing the container B in the workpiece suction unit 1 of this embodiment will be described below. First, as shown in Fig. 4, with the open end of the air passage 4 closed by the cap member 7 of the swing plate 13, the body portion of the container B is pressed against the suction pad 3 provided on the housing 2. At this time, the body portion of the container B closes and crushes the suction pad 3 made of a multi-stage bellows, and the knock bar 11 is pressed toward the base end in the axial direction.

[0040] When the knock rod 11 and rotor 2 descend a predetermined distance (to the lowest position of the knock rod) and the protruding portion 12b leaves the groove 10c, the pressing force of the knock rod 11 is weakened and the biasing force of the coil spring 14 becomes stronger, causing the knock rod 11 and rotor 12 to rise and the rotor 12 to rotate. When the inclined portion 12c is positioned in the valley portion 10e, the rotor 12 and knock rod 11 stop rising and remain at that height. At this time, as shown in Figure 5, the cap member 7, which had temporarily moved away from the open end of the air passage 4, closes the open end of the air passage 4 again, sealing the space within the suction pad 3 against which the body of the container B is pressed and the air passage 4 communicating with it. At this time, a pressure difference is created by the force of the suction pad 3 trying to return to its original position, and the container B is sucked to the suction pad 3.

[0041] Then, when releasing the suction of container B, as shown in Figure 6, container B, which is held by suction pad 3, is pressed again toward the axial base end of knock rod 11. By pressing knock rod 11 again, rotor 2 again descends toward the axial base end against the bias of coil spring 14. As a result, cap member 7 moves away from the open end of air passage 4, opening the space within suction pad 3 and the sealed space of air passage 4 that communicates with it. This releases the suction of container B.

[0042] Then, when the protrusion 12b leaves the valley 10e, the workpiece suction unit 1 weakens the pressing force of the knock rod 11 to allow the biasing force of the coil spring 14 to prevail, and the rotor 12 and knock rod 11 rise again toward the axial tip, as shown in Figure 7, and at that time the inclined portions 12c of the rotor 12 are guided into the grooves 10c in the rotational direction, and the positional and engagement relationship between the knock rod 11 and the rotor 12 returns to its original state. By repeating the pressing operation of the knock rod 11 in this way, it becomes possible to continuously suction and release the container B.

[0043] Next, the workpiece transport device 20 of this embodiment will be briefly described. The work transport device 20 of this embodiment employs a linear transport device of a known configuration, and is a posture switching device that changes the posture of the container B from a rolled-over state to an upright state while holding and transporting the container B. The work transport device 20 is a work transport device in which a container transport path from the receiving position of the container B to the unloading position is allocated within the path along which the above-mentioned work suction unit 1 travels in a circular motion.

[0044] That is, as shown in Figure 8, the work transport device 20 comprises a guide rail (not shown) that forms an endless circulation path, a plurality of moving elements 21 that move along this guide rail, a work suction unit 1 attached to each moving element 21 via a stay 22, and a linear motor (not shown) that moves the moving elements 21 along the guide rail.

[0045] The linear motor comprises a permanent magnet (not shown) fixed to each moving element 21 and a number of electromagnetic coils (not shown) arranged at equal intervals along the longitudinal direction of the guide rail, and the movement and stopping of each moving element 21 can be individually controlled by controlling the supply and stopping of current to each electromagnetic coil with a control unit.

[0046] The guide rail is formed in a track shape and is composed of an upper straight section that is arranged horizontally parallel to the supply conveyor, a lower straight section that is arranged diagonally below it and parallel to the unloading conveyor, a conveying curved section that connects one end of the upper straight section to the lower straight section and changes the posture of container B from a rolled-over state to an upright state when guiding container B from the receiving position to the unloading position, and a return curved section that connects the other end of the lower straight section to the upper straight section.

[0047] At the receiving position for the container B, a robot (not shown) is disposed which grasps the container B supplied in a rolled state onto the supply conveyor, presses it against the suction pad 3, and also presses the knock rod 11 with the grasped container B. At the carrying-out position for the container B, a robot (not shown) is disposed which grasps the suctioned container B, presses the knock rod 11 with the container B, and stands the container B upright on the transfer conveyor in an upright state, and transfers it.

[0048] Next, the operation of the workpiece transport device 20 of this embodiment will be described. In the workpiece transport device 20 of this embodiment, at the receiving position for the container B provided on the upper straight section of the guide rail, the container B held by the robot is pressed from above against the suction pad 3 of the workpiece suction unit 1 connected to the stopped moving element 20, as shown in FIG. 9, to crush the suction pad 3, and at the same time, the knock rod 11 is pressed to operate the double knock mechanism, thereby generating a pressure difference within the suction pad 3 and causing the container to be adsorbed.

[0049] The moving element 21, which supports the workpiece suction unit 1 with the container B adsorbed to the suction pad 3, is caused to travel under the control of the control unit toward the unloading position of the container B in the lower straight section. At that time, the container B is transported in a state where it remains adsorbed even when the moving element 21 passes through the conveying curved section, and reaches the unloading position of the container B.

[0050] When the moving element 21 reaches the carry-out position, the robot presses the container B, which is sucked onto the suction pad 3, from the side, crushing the suction pad 3, and at the same time, it presses the knock rod 11 to activate the double knock mechanism, thereby releasing the differential pressure within the suction pad 3 and releasing the suction, and then the container B is transferred onto the transfer conveyor in an upright position and carried out.

[0051] The work transport device 20 configured in this manner does not require air supply via an air hose, and performs quiet and stable work suction transport, making it suitable for operation under conditions such as long transport distances or complex transport routes.

[0052] The present invention is not limited to the above-described embodiment, and various modifications can be made without departing from the spirit and scope of the present invention.

[0053] For example, the workpiece to be sucked by the workpiece suction unit is not limited to a container.

[0054] The operation of pressing the knock rod and the operation of pressing the workpiece are not limited to the operation by a robot, but may be performed manually. The arrangement position and protruding dimension of the knock rod are not limited to those in the above embodiment. Furthermore, the operation of pressing the knock rod does not have to be performed by the workpiece; for example, a portion for pressing the knock rod may be provided on the device that grips the workpiece.

[0055] Furthermore, the workpiece transport device is not limited to the linear transport device described above, nor is it limited to a transport device that changes the orientation of the workpiece from a rolled-over state to an upright state. For example, even in transport using guide rails that separate different floors or walls, it is possible to perform suction transport of the workpiece by providing the workpiece suction unit of the present invention to the mover that moves on the guide rail. [Explanation of symbols]

[0056] 1 Workpiece suction unit 2. Case 3 suction pads 4 Air passage 7 Cap member 8. Air passage opening / closing means 9 Double knock mechanism 10 Cam body 10a Principle 10b Large diameter cylindrical part 10c groove 10d cam teeth 10e Tanibe 10f screw hole 11 Knock stick 11a cam teeth 11b Operation section 11c long hole 12 rotor 12a empty space 12b Projection 12c Slope 13 Table parts 13a Circular section 13b Table section 14. Biasing member (coil spring) 15 bearings 16 Spring locking part 17 Stopper 18 bis 20 Work transport device 21 Moving Child 22 Stay

Claims

1. The housing and A suction pad disposed on the workpiece suction surface of the housing; an air passage that connects the space inside the suction pad to the back side of the workpiece suction surface; an air passage opening / closing means for opening and closing the open end of the air passage; Equipped with The air passage opening and closing means is A cam body, a knock rod, and a rotor that constitute a double knock mechanism; a cap member disposed opposite an open end of the air passage, and a table member disposed slidably and rotatably relative to the rotor; a biasing member that biases the table member so that the cap member always abuts against the open end of the air passage to close the air passage; It consists of a workpiece suction unit configured so that the open / closed state of the open end of the air passage by the cap member disposed on the table member can be switched by raising and lowering the rotor through a pressing operation of the knock rod.

2. The double knock mechanism The cam body has a plurality of grooves formed in the large-diameter cylindrical portion at the axial tip of the base shaft, the grooves extending in the axial direction, and two series of chevron-shaped cams formed at the base end between the grooves of the large-diameter cylindrical portion, The knock rod is fitted onto the outer periphery of the large-diameter cylindrical portion of the cam body so as to be able to move up and down in the axial direction, and has a cam with a chevron-shaped tooth shape formed at its base end, 2. The workpiece suction unit according to claim 1, wherein the rotor has a plurality of protrusions formed on the inner peripheral surface of a base end side of a cylindrical hollow portion in which the cam body and the knock rod are disposed, the protrusions being fitted into the grooves, and a tip end of each protrusion is formed as an inclined portion that engages with the cam of the cam body and the cam of the knock rod.

3. 3. The workpiece suction unit according to claim 1 or 2, wherein the knock rod is arranged so as to be able to be raised and lowered by a pressing operation in which an operating portion at a tip end of the knock rod projects outward from the workpiece suction surface of the housing and presses the workpiece to be sucked against the suction pad.

4. 4. The workpiece suction unit according to claim 1, wherein a stopper is provided in the housing to regulate the position of the rotor biased by the biasing member via the table member.

5. 5. A work transport device, wherein the work suction unit according to claim 1 is arranged so as to be able to circulate along a work transport path to which a work receiving position and a work carrying-out position are assigned.

6. 6. The workpiece transport device according to claim 5, wherein a robot is disposed at the workpiece receiving position and / or the workpiece carrying-out position for pressing the workpiece against the suction pad and / or for pressing the knock rod.

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