JP2024049790A - Adsorption device - Google Patents

Abstract

[Problem] To provide a suction device capable of lifting an object while preventing excessive load from being applied to the object. [Solution] A suction device 10 having an upper support mechanism 13 including an upper suction pad 11 that contacts the upper side of the object W and an upper suction unit 12 to which the upper suction pad 11 is attached, and which suction-holds the upper side of the object W, and a side support mechanism 16 including a side suction pad 14 that contacts the side of the object W and a side suction unit 15 to which the side suction pad 14 is attached, and which suction-holds the side of the object W, is provided with a lifting body 25 that moves up and down integrally with the upper suction unit 12 relative to a base portion 23, and a control means that brings the lifting body 25 together with the upper suction unit 12 into a state in which they move down relative to the base portion 23 under their own weight, lowers the upper suction unit 12 arranged above the object W together with the lifting body 25, brings the upper side of the object W in a placed state into a state in which it is suction-held by the upper support mechanism 13, and causes the side support mechanism 16 to suction-hold the side of the object W. [Selected Figure] Figure 1

Description

The present invention relates to a suction device that suctions objects.

At sites where goods are loaded, unloaded, or transported, suction devices that suck up and lift goods are used to improve work efficiency and reduce the burden on workers. Suction devices include those disclosed in Patent Documents 1 and 2 that suck up only the top side of goods, and those disclosed in Patent Document 3 that suck up the sides of goods in addition to the top.

For example, the top of a cardboard box containing PET bottles containing beverages has a seam (glued area) where overlapping pieces of cardboard are glued together with hot melt. The adhesive strength of the hot melt is adjusted so that a person can easily release the glue at the seam and open the top of the cardboard box. Therefore, when lifting the cardboard box, if an attempt is made to lift the box by suctioning only the top of the box, there is a risk that the glue at the seam will come undone, so a suction device that suctions the top and sides of the cardboard box is effective.

In general, a suction device that suctions the top and sides of an object moves an upper support mechanism that suctions the top side of the object to a position where it comes into contact with the top side of the object, and then suctions the top side of the object. If there is variation in the height of each object, the suction device determines the height position to which the upper support mechanism should be moved based on the height of the object detected by image recognition technology, etc.

JP 2000-198542 A JP 2020-168700 A Japanese Patent Application Laid-Open No. 11-70917

However, if the detection accuracy of the height of the article is less than a certain level, the suction device cannot accurately position the upper support mechanism at an appropriate height position according to the height of the article. For example, as shown in FIG. 5, when the upper support mechanism 100 is positioned at a higher height position than the appropriate height position relative to the article 101 and the suction unit 102 of the upper support mechanism 100 begins suction, the upper side of the article 101 is suctioned and lifted by the upper support mechanism 100 before the side support mechanism 103 suctions the article 101 (i.e., when the side support mechanism 103 has not yet suctioned the article 101), causing a problem that excessive load is placed on the upper side of the article 101.

Note that Figure 5 (also Figure 6) shows an example in which a suction pad 105 that contacts the article 101 is attached to the suction unit 102, and the side support mechanism 103 has a suction unit 104 and a suction pad 106 that is attached to the suction unit 104 and contacts the article 101. The suction pads 105, 106 are formed of an elastic body that is compressed when the suction units 102, 104 suck the article 101.

On the other hand, if the upper support mechanism 100 is positioned at a height lower than an appropriate height relative to the article 101, as shown in Figure 6, a problem occurs in which the upper support mechanism 100 applies a load to the entire article 101 in a direction that crushes the article 101.
In this regard, it is conceivable to solve the above-mentioned problems by employing a system that can detect the height of an article with a certain level of accuracy or higher. However, employing such a system would give rise to other problems, such as a longer time until the height of the article is detected and higher manufacturing costs for the entire suction device.
Furthermore, there are limitations to the precision with which the shape of each object can be made uniform (for example, to prevent the formation of protrusions that protrude upward from the top of the object) and to the manufacturing precision of the equipment (for example, the pallet on which the objects are placed), so even if the detection precision of the object height is increased to a certain level or higher, the above-mentioned problem of excessive stress being placed on the object will still occur.

The present invention was made in consideration of these circumstances, and aims to provide a suction device that can lift objects while preventing excessive load from being placed on the objects.

The suction device according to the present invention, which is in line with the above-mentioned objective, has an upper support mechanism that includes an upper suction pad that contacts the upper side of an object and an upper suction unit to which the upper suction pad is attached, and suction-holds the upper side of the object, and a lateral support mechanism that includes a side suction pad that contacts the side of the object and a side suction unit to which the side suction pad is attached, and suction-holds the side of the object, and the suction device has a lifting body that rises and falls together with the upper suction unit relative to a base portion, and the lifting body rises together with the upper suction unit due to the action of an upward force. The device is equipped with a switching means for switching between an elevated state in which the lifting body is raised by the load applied to the lifting unit and a self-weight descent state in which the lifting body is lowered by its own weight relative to the base together with the upper suction unit, and a control means for controlling the upper suction unit, the side suction unit, and the switching means, and the control means sets the switching means to the self-weight descent state, lowers the upper suction unit arranged above the placed article together with the lifting body, sets the upper side of the placed article to a state in which it is adsorbed and held by the upper support mechanism, and causes the side support mechanism to adsorb and hold the side of the article.

The suction device according to the present invention comprises a lifting body which rises and falls together with the upper suction unit relative to the base, a switching means for switching between an ascending state in which the lifting body rises together with the upper suction unit due to the action of an upward force, and a self-weight descending state in which the lifting body descends together with the upper suction unit relative to the base due to its own weight, and a control means for controlling the upper suction unit, the side suction unit, and the switching means. The control means sets the switching means to a self-weight descending state, lowers the upper suction unit arranged above the placed object together with the lifting body, and causes the upper side of the placed object to be adsorbed and held by the upper support mechanism, and causes the side support mechanism to adsorb and hold the side of the object. This makes it possible to stably lower the upper suction unit from a position higher than the position at which the upper support mechanism crushes the object, and to avoid the upper side of the object being adsorbed and held by the upper support mechanism when it has lifted the object before adsorbing and holding the side of the object, and as a result, it is possible to lift the object while preventing excessive load from being placed on the object.

1 is an explanatory diagram of a suction device according to an embodiment of the present invention; FIG. 2 is a block diagram showing connections of a control means. 13A and 13B are explanatory diagrams illustrating the process in which the suction device lifts up an article placed on a placement surface. 13A and 13B are explanatory diagrams illustrating the process in which the suction device lifts up an article placed on a placement surface. FIG. 13 is an explanatory diagram showing a state in which a suction device according to a conventional example applies a load to an article. FIG. 13 is an explanatory diagram showing a state in which a suction device according to a conventional example applies a load to an article.

Next, with reference to the attached drawings, an embodiment of the present invention will be described for understanding the present invention.
1, a suction device 10 according to an embodiment of the present invention has an upper support mechanism 13 including an upper suction pad 11 that contacts the upper side of an article W and an upper suction unit 12 to which the upper suction pad 11 is attached, and suction-holds the upper side of the article W, and a side support mechanism 16 including a side suction pad 14 that contacts the side of the article W and a side suction unit 15 to which the side suction pad 14 is attached, and suction-holds the side of the article W. A detailed description will be given below.

As shown in FIG. 1, the item W in this embodiment is a roughly rectangular parallelepiped cardboard box containing a PET bottle containing a beverage, and the upper side (the upper surface in this embodiment) has a seam (glued portion) formed by gluing overlapping cardboard pieces with hot melt H.
The upper suction pad 11 and the upper suction unit 12 provided in the upper support mechanism 13 are both rectangular (including square) in plan view and of the same size, and the upper suction pad 11 is adhered with an adhesive to the lower end of the upper suction unit 12. A hole (not shown) is formed in the upper suction unit 12, and the upper suction unit 12 can take in air into the hole from the lower end.

As shown in FIG. 2, the upper suction unit 12 is connected to an air compressor 19 via a solenoid valve 17 and a regulator 18, and the solenoid valve 17 and the air compressor 19 are connected to a control means 20 that can be configured by an electronic circuit or the like. The control means 20 can control the solenoid valve 17 and the air compressor 19 by sending command signals to the solenoid valve 17 and the air compressor 19. In the following description, unless otherwise specified, it is assumed that the air compressor 19 is operating (is in a state where it can send compressed air to the solenoid valve 17, etc.).

When the control means 20 sets the solenoid valve 17 to a state where compressed air sent from the air compressor 19 is supplied to the upper suction unit 12, the upper suction unit 12 creates negative pressure in the hole formed in the upper suction unit 12 and sucks in air from the lower end. On the other hand, when the control means 20 sets the solenoid valve 17 to a state where compressed air from the air compressor 19 is not sent to the upper suction unit 12, the upper suction unit 12 stops sucking in air. Therefore, the control means 20 indirectly controls the upper suction unit 12 (switches the state of the upper suction unit 12) by controlling the solenoid valve 17 and the air compressor 19.

The upper suction pad 11 is made of an elastic body, and multiple through holes (not shown) are formed in the upper suction pad 11, which pass vertically through the upper suction pad 11. Therefore, when the upper suction unit 12 is in a state of sucking in air from the lower end, the air below the upper suction pad 11 is sucked into the upper suction unit 12 via the multiple through holes formed in the upper suction pad 11.

As shown in FIG. 1, above the upper suction unit 12, there is provided an air cylinder 26 having a cylinder tube 23, which is an example of a base portion connected to the robot arm 22, a piston 24 that rises and falls within the cylinder tube 23, and a rod 25, which is an example of a vertically arranged lifting body whose upper end is connected to the piston 24. A connecting member 27, to which the upper suction unit 12 is fixed on the lower side, is attached to the lower end of the rod 25 that protrudes downward from the cylinder tube 23.

The cylinder tube 23, whose axis is vertical, is connected to the air compressor 19 via a solenoid valve 29 and a regulator 30, which are examples of switching means each connected to the control means 20, as shown in FIG. 2. The control means 20 can control the solenoid valve 29 so that compressed air from the air compressor 19 is provided to the area below the piston 24 in the cylinder tube 23 (hereinafter referred to as the "lower area"), open the cylinder tube 23 to the atmosphere, and prevent air from flowing in or out of the cylinder tube 23.

When the solenoid valve 29 is in a state where it sends compressed air to the lower region inside the cylinder tube 23, an upward force acts on the piston 24, causing the rod 25 to rise together with the upper suction unit 12, the connecting member 27, and the piston 24 relative to the cylinder tube 23. The state of the solenoid valve 29 at this time is called the "rising state." When the solenoid valve 29 is in the rising state, an upward force acts on the rod 25 via the piston 24 (i.e., the rod 25 is subjected to an upward force and rises together with the upper suction unit 12).

In addition, when the solenoid valve 29 is in a state where it opens the inside of the cylinder tube 23 to the atmosphere, the rod 25, together with the upper suction unit 12, the connecting member 27, and the piston 24, is lowered relative to the cylinder tube 23 by the weight of the rod 25, the upper suction unit 12, the connecting member 27, the piston 24, etc. The state of the solenoid valve 29 at this time is called the "weight-lowering state." Therefore, the solenoid valve 29 can be switched between the raised state and the weight-lowering state by the control means 20.

Then, with the rod 25 and the piston 24 positioned at their upper limit relative to the cylinder tube 23, the solenoid valve 29 is in a state where it sends compressed air to the lower region within the cylinder tube 23, and the rod 25 is fixed to the cylinder tube 23 together with the upper suction unit 12, the connecting member 27 and the piston 24.
In addition, a pressure sensor 28 that measures the pressure inside the cylinder tube 23 is connected to the control means 20 .

When the upper suction unit 12 rises and falls with the lower end of the upper suction pad 11 not in contact with the article W, the upper suction pad 11 rises and falls together with the upper suction unit 12 without deforming. On the other hand, when the upper suction unit 12 descends with the lower end of the upper suction pad 11 in contact with the article W, the upper suction pad 11 deforms and is compressed vertically. The upper suction pad 11, whose lower end has come into contact with the article W and been compressed vertically, returns to its original state as the upper suction unit 12 rises.

Instead of the upper suction pad 11, it is also possible to use an upper suction pad that does not substantially deform elastically. Such an upper suction pad always rises and falls together with the upper suction unit 12. It goes without saying that when the lower end of the upper suction pad is in contact with the upper side of the article W, neither the upper suction unit 12 nor the upper suction pad can descend, even if the upper suction unit 12 etc. are able to rise and fall relative to the cylinder tube 23.

Also, as shown in FIG. 1, a cylinder tube 33 of an air cylinder 32 with a rod 31 arranged horizontally is fixed to the connecting member 27. A piston 34 connected to one end of the rod 31 is provided inside the cylinder tube 33 with its axis arranged horizontally. The upper side of a vertically long arm 35 is fixed to the other end of the rod 31 protruding from the cylinder tube 33, and the side suction unit 15 is attached to the lower side of the arm 35.

The side suction unit 15 and side suction pad 14 of the side support mechanism 16 are both rectangular (including square) shapes of the same size when viewed from the side. The side suction pad 14 is attached with an adhesive to one horizontal side of the side suction unit 15 (the side opposite to the side attached to the arm 35). The side suction unit 15 has a hole (not shown) that opens one horizontal end.

As shown in FIG. 2, the side suction unit 15 is connected to the air compressor 19 via the solenoid valve 36 and regulator 18, which are connected to the control means 20. The control means 20 can control the solenoid valve 36 by sending a command signal to the solenoid valve 36. When the control means 20 sets the solenoid valve 36 to a state in which compressed air sent from the air compressor 19 is provided to the side suction unit 15, the side suction unit 15 creates negative pressure in the hole opening at one horizontal end, and sucks in air from the one horizontal end.

On the other hand, the control means 20 sets the solenoid valve 36 to a state in which compressed air from the air compressor 19 is not sent to the side suction unit 15, so that the side suction unit 15 does not suck in air. Therefore, the control means 20 indirectly controls the side suction unit 15 (switches the state of the side suction unit 15) by controlling the solenoid valve 36 and the air compressor 19.

The side suction pad 14 is made of an elastic body, and multiple through holes (not shown) are formed in the side suction pad 14 that pass horizontally through the side suction pad 14. Therefore, when the side suction unit 15 is in a state of sucking in air from one horizontal end, the air around one horizontal side of the side suction pad 14 is sucked into the side suction unit 15 via the multiple through holes formed in the side suction pad 14.

As shown in FIG. 2, the cylinder tube 33 is connected to the air compressor 19 via a solenoid valve 37 and a regulator 30 connected to the control means 20. The control means 20 can control the solenoid valve 37 so that compressed air from the air compressor 19 is provided to either an area on one horizontal side of the piston 34 in the cylinder tube 33 (hereinafter referred to as the "first area") or an area on the other horizontal side of the cylinder tube 33 (hereinafter referred to as the "second area"), open either or both of the first and second areas in the cylinder tube 33 to the atmosphere, or prevent air from flowing in or out of the cylinder tube 33.

The lateral suction unit 15, piston 34, and rod 31 move together with the cylinder tube 33 to the other horizontal side (in the direction in which the length of the rod 31 protruding from the cylinder tube 33 becomes longer) as a result of compressed air being sent to the first region in the cylinder tube 33 and the second region being opened to the atmosphere. Also, the lateral suction unit 15, piston 34, and rod 31 move together with the cylinder tube 33 to one horizontal side (in the direction in which the length of the rod 31 protruding from the cylinder tube 33 becomes shorter) as a result of the first region in the cylinder tube 33 being opened to the atmosphere and compressed air being sent to the second region.

Then, by preventing air from flowing in or out of the cylinder tube 33, the side suction unit 15, the piston 34, and the rod 31 are fixed to the cylinder tube 33. A pressure sensor 28a that measures the pressure inside the cylinder tube 33 is connected to the control means 20.

When the side suction unit 15 moves horizontally to one side relative to the cylinder tube 33 with one horizontal end of the side suction pad 14 not in contact with the article W, the side suction pad 14 moves horizontally to one side relative to the cylinder tube 33 together with the side suction unit 15 without deforming. In contrast, when the side suction unit 15 moves horizontally to one side relative to the cylinder tube 33 with one horizontal end of the side suction pad 14 in contact with the article W, the side suction pad 14 deforms and is compressed horizontally. Then, the side suction pad 14, which has been compressed horizontally with one horizontal end in contact with the article W, is restored as the side suction unit 15 moves horizontally to the other side relative to the cylinder tube 33. Note that a side suction pad that does not substantially deform elastically may be used instead of the side suction pad 14.

In addition, the control means 20 is connected to a pressure sensor 38 that detects the pressure inside a hole opening at the lower end of the upper suction unit 12, a pressure sensor 39 that detects the pressure inside a hole opening at one horizontal end of the side suction unit 15, and an image analysis means 41 that detects the position of the item W based on an image captured by the imaging means 40 of the item W.

Next, we will explain the process of lifting an item W placed on a placement surface G using the suction device 10.

<Step 1>
The image analysis means 41 detects the overall position of the item W, the height position of the upper side of the item W, and the lateral position of the item W supported by the lateral support mechanism 16 based on the image captured by the imaging means 40 of the item W placed on the loading surface G.

<Step 2>
The control means 20 acquires various position information of the article W from the image analysis means 41, and operates the robot arm 22 based on the information to move the air cylinders 26, 32, the upper support mechanism 13, the side support mechanism 16, etc., so that the upper suction unit 12 is disposed at a predetermined position directly above the article W placed on the placement surface G as shown in Fig. 3(A), and stops the robot arm 22. The predetermined position directly above the article W means a position of the upper suction unit 12 where the air cylinder 26 can increase the protruding length of the rod 25 from the cylinder tube 23 to lower the upper suction unit 12, and where the air cylinder 32 can decrease the protruding length of the rod 31 from the cylinder tube 33 to move the side suction unit 15 to one side in the horizontal direction.

In addition, when the upper suction unit 12 is placed at a predetermined position directly above the item W, the upper suction pad 11 may or may not be in contact with the upper side of the item W, but the upper suction unit 12 must be placed within a height range that does not apply excessive load (e.g., load that crushes the item W) to the upper part of the item W via the upper suction pad 11, and allows the upper support mechanism 13 to suction and hold the upper side of the item W without lifting it from the loading surface G by increasing the protruding length of the rod 25 from the cylinder tube 23.

Furthermore, when the upper suction unit 12 is positioned at a predetermined position directly above the article W, the side suction pad 14 must be positioned so that it does not come into contact with the side of the article W, and the side support mechanism 16 can suction and hold the side of the article W by shortening the length of the rod 31 protruding from the cylinder tube 33.

<Step 3>
Next, the control means 20 controls the solenoid valve 29 (i.e., the switching means) to open the inside of the cylinder tube 23 to the atmosphere, i.e., to bring the solenoid valve 29 into a state of descending under its own weight, and lowers the upper suction unit 12 arranged above the article W placed on the loading surface G together with the rod 25, etc., so that the upper side of the article W placed on the loading surface G is adsorbed and held by the upper support mechanism 13.

Here, the amount of air released per unit time from the lower region inside the cylinder tube 23 is adjusted (limited) by a flow control valve (one example of a resistance force applying means that applies resistance to the descent of the lifting body) not shown that corresponds to the cylinder tube 23. The descent speed of the upper suction unit 12 and the rod 25, etc. is adjusted by adjusting (limiting) the amount of air released per unit time. In step 3 and step 4 described below, the cylinder tube 23 is kept fixed by the robot arm 22. Therefore, the control means 20 sets the solenoid valve 29 to a gravity descent state with the cylinder tube 23 fixed.

In this embodiment, when the upper suction unit 12 is lowered together with the rod 25, etc., the control means 20 controls the solenoid valve 17 to put the upper suction unit 12 into a suction state, so that the suction of air from the lower end of the upper suction pad 11 by the suction of the upper suction unit 12 (i.e., the suction of the upper suction unit 12) contributes to the descent of the upper suction unit 12 and the rod 25, etc. (the suction force of the upper suction unit 12 contributes to the force that lowers the upper suction unit 12 and the rod 25, etc.).

Therefore, until the upper support mechanism 13 adsorbs and holds the upper side of the item W placed on the loading surface G, the rod 25 and the upper suction unit 12, etc. will descend due to the weight of the rod 25, the upper suction unit 12, the upper suction pad 11, etc., and the suction force of the upper suction unit 12.
As shown in Figure 3 (B), the upper suction unit 12 and the rod 25, etc., descend and stop until the upper suction pad 11 is sandwiched between the upper suction unit 12 and the item W and compressed vertically, and the upper support mechanism 13 is in a state of adsorbing and holding the item W.

The control means 20 detects that the measurement value of the pressure sensor 38 has exceeded a predetermined value, and detects that the upper support mechanism 13 has adsorbed and held the upper side of the article W. In this embodiment, the state in which the upper support mechanism 13 has adsorbed and held the upper side of the article W means a state in which the measurement value of the pressure sensor 38 has exceeded a preset value (a state in which the upper support mechanism 13 is adsorbing the upper side of the article W with a force equal to or greater than a predetermined magnitude).

Here, if an upper suction pad that does not substantially elastically deform is used instead of the upper suction pad 11, in step 2, when the robot arm 22 stops, the upper suction pad is positioned at a height position with a distance to the upper side of the article W, and in step 3, when the upper suction unit 12 is lowered together with the rod 25, etc., the rod 25 and the upper suction unit 12 are lowered by the weight of the rod 25, the upper suction unit 12, etc., so there is no need to put the upper suction unit 12 into a suction state. However, when the upper suction unit 12 is lowered together with the rod 25, etc. without being in a suction state, in order to have the upper support mechanism suction and hold the article W, it is necessary to suck the upper suction unit 12 with the upper suction pad in contact with the upper side of the article W.

<Step 4>
Next, the control means 20 controls the solenoid valve 37 to send compressed air to the other end inside the cylinder tube 33, thereby moving the rod 31 together with the side support mechanism 16 and the arm 35 to one side in the horizontal direction relative to the cylinder tube 33, and bringing the side suction pad 14 into contact with the side of the article W, as shown in Fig. 4(A) . In this embodiment, when moving the rod 31, the side support mechanism 16, etc. to one side in the horizontal direction, the control means 20 controls the solenoid valve 36 to put the side suction unit 15 into a suction state, so that the suction of air from one side of the horizontal direction of the side suction pad 14 by the suction of the side suction unit 15 also contributes to the movement of the rod 31, the side support mechanism 16, etc. to one side in the horizontal direction.

The rod 31 and the side support mechanism 16, etc., move horizontally to one side and stop until the side suction pad 14 is sandwiched between the side suction unit 15 and the article W and compressed and deformed in the horizontal direction, and the side support mechanism 16 is in a state of suction-holding the article W. Therefore, in this embodiment, the control means 20 causes the upper support mechanism 13 to suction-hold the upper side of the article W, and causes the side suction unit 15 to start suction, causing the side support mechanism 16 to suction-hold the side of the article W.

The state in which the side support mechanism 16 suctions and holds the article W means a state in which the measurement value of the pressure sensor 39 is equal to or greater than a preset value (a state in which the side support mechanism 16 suctions and holds the article W with a force equal to or greater than a predetermined force). The control means 20 detects that the measurement value of the pressure sensor 39 is equal to or greater than the predetermined value, and detects that the side support mechanism 16 has suctioned and held the side of the article W, and fixes the rod 31 to the cylinder tube 33 by controlling the solenoid valve 37 so that air is not released from inside the cylinder tube 33. In addition, if a side suction pad that does not substantially elastically deform is used instead of the side suction pad 14, the side support mechanism suctions and holds the side of the article W without the side suction pad deforming.

<Step 5>
With the upper support mechanism 13 suction-holding the upper side of the article W and the side support mechanism 16 suction-holding the side of the article W, the control means 20 controls the solenoid valve 29 to send compressed air to the lower region of the cylinder tube 23, as shown in Figure 4 (B), i.e., brings the solenoid valve 29 into an elevated state to raise the rod 25 relative to the cylinder tube 23, and also controls the robot arm 22 to operate the robot arm 22 to raise the cylinder tube 23, thereby lifting the article W from the mounting surface G.

By going through steps 1 to 5 described above, it is possible to reliably prevent the upper support mechanism 13 from applying excessive load to the item W in a direction that would crush the item W, or from lifting the item W while the upper support mechanism 13 is suction-holding the item W alone, thereby making it possible to lift the item W while preventing excessive load from being applied to the entire item W.

Although the embodiment of the present invention has been described above, the present invention is not limited to the above-mentioned embodiment, and all changes in conditions that do not depart from the gist of the present invention are within the scope of application of the present invention.
For example, it goes without saying that the object to be sucked and held by the suction device is not limited to a cardboard box containing a plastic bottle containing a beverage. The shape of the object may be any shape that can be sucked by the upper support mechanism and the side support mechanism, and may be, for example, a triangular prism or a cylinder.

In addition, it is not necessary to use an air cylinder with a lifting body. Instead of an air cylinder, for example, it is possible to use an electric cylinder with a rod as the lifting body, or a mechanism with a rack as the lifting body and a pinion that meshes with the rack. However, when an electric cylinder is used, the time required from when the upper support mechanism holds the upper side of the article by suction until this state is detected is longer than when an air cylinder is used. Also, when a mechanism with a rack and pinion is used, it is necessary to put the pinion in neutral so that the rack can be raised and lowered, making the design more complex than when an air cylinder is used.

The side support mechanism does not have to be raised and lowered integrally with the lifting body and the upper suction unit, in which case a mechanism for raising and lowering only the side support mechanism may be provided to raise and lower the side support mechanism.
Furthermore, the position of the article does not have to be detected by an imaging means and an image analysis means, and the position of the article may be detected by using, for example, a laser distance meter or a photoelectric sensor.

10: Suction device, 11: Upper suction pad, 12: Upper suction unit, 13: Upper support mechanism, 14: Side suction pad, 15: Side suction unit, 16: Side support mechanism, 17: Solenoid valve, 18: Regulator, 19: Air compressor, 20: Control means, 22: Robot arm, 23: Cylinder tube, 24: Piston, 25: Rod, 26: Air cylinder, 27: Connection member, 28, 28a: Pressure sensor, 29: Solenoid valve, 30: Regulator, 31: Rod, 32: Air cylinder, 33: Cylinder tube, 34: Piston, 35: Arm, 36, 37: Solenoid valve, 38, 39: Pressure sensor, 40: Imaging means, 41: Image analysis means, G: Placement surface, H: Hot melt, W: Item

Claims (4)

A suction device having an upper support mechanism including an upper suction pad that comes into contact with an upper side of an article and an upper suction unit to which the upper suction pad is attached, and which suction-holds the upper side of the article, and a side support mechanism including a side suction pad that comes into contact with a side of the article and a side suction unit to which the side suction pad is attached, and which suction-holds the side of the article,
a lifting body that moves up and down together with the upper suction unit relative to a base portion;
a switching means for switching between an ascending state in which the ascending/descending body is acted upon by an upward force and ascends together with the upper suction unit, and a gravity descending state in which the ascending/descending body descends together with the upper suction unit by its own weight relative to the base portion;
a control unit for controlling the upper suction unit, the side suction unit, and the switching unit,
The control means sets the switching means to the gravity descending state, lowers the upper suction unit arranged above the placed item together with the lifting body, causes the upper side of the placed item to be adsorbed and held by the upper support mechanism, and causes the side support mechanism to adsorb and hold the side of the item. The suction device according to claim 1, characterized in that the control means puts the upper suction unit into a suction state and causes the suction of the upper suction unit to contribute to the descent of the upper suction unit. The suction device according to claim 1 or 2, characterized in that the upper suction pad is formed of an elastic body and is compressed between the upper suction unit and the object while the upper support mechanism is suction-holding the upper side of the object. The suction device according to claim 1 or 2, characterized in that it is equipped with an air cylinder having a cylinder tube as the lifting body and the base part.

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