Nozzle drive device

Abstract

Preventing damage to the workpiece [Solution] The nozzle drive device includes a nozzle holding structure guided vertically and horizontally with respect to the frame via a guide structure; a workpiece suction nozzle attached to the lower member of the nozzle holding structure; an actuator attached to the frame having a drive shaft that penetrates the upper member of the nozzle holding structure vertically and is vertically movable; a collar attached to the drive shaft so as to be located below the upper member of the nozzle holding structure and contacting the upper member to support the upper member from below; and a compression spring interposed between the frame and the nozzle holding structure, which is compressed when the nozzle holding structure rises and extends when the nozzle holding structure descends. When an upward impact load is applied to the workpiece while the workpiece held by the suction nozzle is descending, the compression spring is compressed and the upper member of the nozzle holding structure separates from the collar, thereby cushioning the impact on the workpiece.

Description

Technical Field

[0001] The present disclosure relates to a nozzle driving device that drives an adsorption nozzle in a work transfer device that adsorbs and transfers a work by the adsorption nozzle.

Background Art

[0002] For example, electronic components such as capacitors and resistors (hereinafter also referred to as "work") are arranged at predetermined intervals using a parts feeder, and then adsorbed one by one by an adsorption nozzle, and stored in a storage member such as a pallet in which a parts storage cavity (storage recess) is formed. A system that performs such processing is disclosed in Patent Document 1.

[0003] When the adsorption nozzle attempts to store an electronic component in the storage cavity in a state where the storage member is displaced from the position where it should be, the electronic component may collide with the entrance of the storage recess and be damaged.

Prior Art Documents

Patent Documents

[0004]

Patent Document 1

Summary of the Invention

Problems to be Solved by the Invention

[0005] An object of the present disclosure is to provide a nozzle driving device that can prevent damage to a work even when the work adsorbed by an adsorption nozzle collides with a storage member due to displacement of the storage member or the like.

Means for Solving the Problems

[0006] According to one embodiment of the present invention, a nozzle drive device is provided, comprising: a frame; a nozzle holding structure having an upper member and a lower member connected to each other and guided to move up and down relative to the frame via a guide structure; a suction nozzle for adsorbing a workpiece, attached to the lower member of the nozzle holding structure; an actuator attached to the frame, having a drive shaft that penetrates the upper member of the nozzle holding structure in the vertical direction and is movable up and down; a collar attached to the drive shaft so as to be located below the upper member of the nozzle holding structure and in contact with the upper member to support the upper member from below; and a compression spring interposed between the frame and the nozzle holding structure, which is compressed when the nozzle holding structure rises and extends when the nozzle holding structure descends, wherein when an upward impact load is applied to a workpiece while the workpiece adsorbed by the suction nozzle is descending, the compression spring is compressed and the upper member of the nozzle holding structure separates from the collar, thereby cushioning the impact on the workpiece.

[0007] In one preferred embodiment, the guide structure includes a linear shaft connecting the upper member and the lower member of the nozzle holding structure, and a linear bearing provided on the frame that guides the linear shaft so as to be movable in the vertical direction.

[0008] In another preferred embodiment, the upper member of the nozzle holding structure has a spherical bearing, the drive shaft of the actuator is passed through a hole through the ball portion of the spherical bearing, a gap is provided between the drive shaft and the hole, and the nozzle holding structure is supported by the collar by the end face of the ball portion contacting the collar.

[0009] In yet another preferred embodiment, a proximity sensor is provided to detect when the workpiece held by the suction nozzle has descended appropriately to a target position, wherein the proximity sensor is fixed to the frame and is configured to detect the proximity of the nozzle holding structure. [Effects of the Invention]

[0010] According to the above embodiment, damage to the workpiece can be prevented. [Brief explanation of the drawing]

[0011] [Figure 1] This is a partially fractured front view of a nozzle drive device according to one embodiment of the present invention. [Figure 2] Figure 1 is a partially broken front view of the nozzle drive unit, showing the state of the nozzle drive unit when the workpiece is properly stored in the storage member. [Figure 3] Figure 1 is a partially broken front view of the nozzle drive unit, showing the state of the nozzle drive unit when the workpiece collides with the storage member. [Figure 4] This diagram illustrates the role of spherical bearings. [Figure 5] This is a schematic diagram showing an example of a workpiece transport system incorporating the nozzle drive device shown in Figure 1. [Modes for carrying out the invention]

[0012] A preferred and non-limiting embodiment of the nozzle drive device 1 according to this disclosure will be described below with reference to the attached drawings.

[0013] The nozzle drive device 1 includes a frame (machine frame) 10, a nozzle holding structure 20, a suction nozzle 30, and an actuator 40.

[0014] The frame 10 includes a vertically extending support column 11, a plate-shaped actuator holder 12 extending horizontally from the upper part of the support column 11, a plate-shaped linear bearing holder 13 extending horizontally from the lower part of the support column 11, and a plate-shaped bush holder 14 extending horizontally from the support column 11 at a height between the actuator holder 12 and the linear bearing holder 13.

[0015] The actuator 40 has a main body portion 41, a drive shaft 42 passing through the main body portion 41, and a return spring 43. The main body portion 41 of the actuator 40 is fixed to the actuator holding portion 12.

[0016] The drive shaft 42 moves downward by energizing a drive mechanism (e.g., a solenoid) stored inside the main body portion 41, and returns upward by the return spring 43 when the energization to the solenoid is cut off.

[0017] The lower limit position of the drive shaft 42 is defined by the opposing surfaces of appropriate mechanical stopper means, for example, the upper spring seat 44 and the lower spring seat 45 of the return spring 43 colliding with each other. The upper limit position of the drive shaft 42 is defined by the balance between the spring force of the return spring 43 and the spring force of a compression spring 50 described later. Although it is not necessary to strictly define the upper limit position of the drive shaft 42, appropriate mechanical stopper means for defining the upper limit position of the drive shaft 42 may be set.

[0018] The structure of the actuator 40 is not limited to the one described above, and any structure can be adopted as long as it can move the drive shaft 42 in the vertical direction and can strictly define the lower limit position of the drive shaft 42.

[0019] A linear bush 15 is attached to the bush holding portion 14. The linear bush 15 guides the lifting and lowering movement (vertical movement) of the drive shaft 42 passed through the through hole at the center thereof.

[0020] The nozzle holding structure 20 has a plate-shaped upper member 21 and a lower member 22, and a pair of linear shafts 23 that firmly connect the upper member 21 and the lower member 22. A suction nozzle 30 is held by the lower member 22. That is, the lower member 22 is a nozzle holder (nozzle holding portion).

[0021] A vacuum device (not shown) is connected to the suction nozzle 30 via piping or the like (not shown), and the suction nozzle 30 can suction a workpiece W such as an electronic component as needed and can also release the suction of the workpiece W.

[0022] A pair of linear bushes, that is, linear bearings 16 are attached to the linear bearing holder 13. One corresponding linear shaft 23 is passed through each linear bush 16. The nozzle holding structure 20 can move up and down while being guided by the linear bushes 16. That is, the linear bushes 16 and the linear shafts 23 constitute a guide structure for guiding the nozzle holding structure 20 so that it can move up and down.

[0023] A spherical bearing 24 is attached to the upper member 21 of the nozzle holding structure 20. The spherical bearing 24 has a race portion 25 and a ball portion 26 that can swing within the race portion 25. The drive shaft 42 of the actuator 40 passes through a hole 27 that penetrates the ball portion 26. There is a gap between the outer peripheral surface of the drive shaft 42 and the inner peripheral surface of the hole 27.

[0024] A collar 46 having a larger diameter than the hole 27 of the ball portion 26 of the spherical bearing 24 is attached to the lower end portion of the drive shaft 42 of the actuator 40. The collar 46 seats on the lower end face 28 of the ball portion 26 of the spherical bearing 24, and thereby the weight of the nozzle holding structure 20 is supported by the actuator 40.

[0025] A pair of compression springs 50 in the form of coil springs are provided between the lower member 22 of the nozzle holding structure 20 and the linear bearing holder 13 of the frame 10.

[0026] The vertical distance between the lower member 22 and the linear bearing holder 13 increases when the drive shaft 42 of the actuator 40 is lowered and decreases when it is raised. As the vertical distance changes, the compression springs 50 expand and contract.

[0027] The overall length of the compression spring 50 is set such that the compression spring 50 is compressed even when the drive shaft 42 is at its lower limit position, that is, when the vertical distance between the lower member 22 and the bush holding portion 14 is at its maximum.

[0028] The nozzle holding structure 20 is constantly trying to move downward due to its weight. This downward movement is stopped by the collar 46. Therefore, when the drive shaft 42 of the actuator 40 is lowered, the nozzle holding structure 20 descends while maintaining contact between the collar 46 and the lower end face 28 of the ball portion 26 of the spherical bearing 24, and as a result the suction nozzle 30 attached to the lower member 22 of the nozzle holding structure 20 descends.

[0029] When the drive shaft 42 of the actuator 40 is raised, the nozzle holding structure 20 rises while maintaining contact with the lower end face 28 of the ball portion 26 of the spherical bearing 24, and as a result the suction nozzle 30 attached to the lower member 22 of the nozzle holding structure 20 rises. This makes it possible to move the workpiece W that has been picked up by the suction nozzle 30 up and down between different height positions.

[0030] The compression spring 50, which is constantly compressed, generates a force that brings the collar 46 into close contact with the ball portion 26 of the spherical bearing 24. As a result, even when the drive shaft 42 of the actuator 40 is moved up and down at a relatively high speed, the contact between the collar 46 and the ball portion 26 of the spherical bearing 24 is maintained. Therefore, the suction nozzle 30 and the workpiece it holds can be made to move in a controlled manner as intended.

[0031] Furthermore, if the drive shaft 42 is moved at a relatively high speed, the spring force of the compression spring 50 may cause the nozzle holding structure 20 to vibrate relative to the frame 10. However, in reality, such vibration does not occur due to the friction acting between the linear bush 16 and the linear shaft 23.

[0032] As shown in Figure 4, the spherical bearing 24 plays a role in ensuring that the lower end face 28 of the ball portion 26 of the spherical bearing 24 makes reliable surface contact with the upper surface of the collar 46, for example, when the drive shaft 42 is tilted relative to the vertical. The spherical bearing 24 can be omitted if the manufacturing and assembly precision of the components of the nozzle drive device 1 is sufficiently high. In other words, the configuration in which the upper member 21 of the nozzle holding structure 20 is supported by the collar 46 via the spherical bearing 24 is not limited to the illustrated embodiment, but a configuration in which the upper member 21 is directly supported by the collar 46 is also conceivable.

[0033] As will be explained later with reference to Figure 5, the storage member 60 has numerous recesses (storage recesses) 61 arranged at equal intervals, for example, in a matrix. An index feeding mechanism (not shown) indexes each recess 61 so that it is successively positioned directly below the suction nozzle 30.

[0034] When the drive shaft 42 of the actuator 40 is lowered while the recess 61 is properly positioned, the workpiece W is properly housed in the recess 61, as shown in Figure 2.

[0035] If the recess 61 is misaligned from its intended position, the workpiece W will collide with the vicinity of the entrance to the recess 61, for example, as shown in Figure 3. When the workpiece W is pushed upward by the collision, the nozzle holding structure 20 is also displaced upward, resulting in the compression spring 50 being compressed and the collar 46 separating from the ball portion 26 of the spherical bearing 24. This cushions the impact on the workpiece W and prevents damage to the workpiece W. At this time, the driving force of the actuator 40 is not applied to the workpiece W.

[0036] The frame 10 further has a proximity sensor holding portion 17 that extends horizontally from the support column portion 11. A proximity sensor 18 is attached to the tip of the proximity sensor holding portion 17. The proximity sensor 18 detects when it approaches the nozzle holding structure 20 (upper member 21 in the illustrated example), thereby detecting that the workpiece W has descended to an appropriate height. Once it is detected that the workpiece W has descended to an appropriate height, the suction nozzle 30 releases its grip on the workpiece W.

[0037] When the workpiece W is thrust upward due to a collision, the nozzle holding structure 20 is unable to descend to a predetermined height position. Therefore, even if the drive shaft of the actuator 40 descends to its lower limit position, the proximity sensor 18 does not detect that it is approaching the nozzle holding structure 20 (upper member 21 in the illustrated example). This allows for the detection of some kind of abnormality, such as a collision.

[0038] For example, an abnormality can be detected by comparing data from a sensor that detects when the drive shaft of the actuator 40 has lowered to its lower limit position with data from the proximity sensor 18. Alternatively, an abnormality can be determined if the proximity sensor 18 does not detect that it has come close to the nozzle holding structure 20 even after a predetermined time has elapsed since the start of energization to the solenoid of the actuator 40.

[0039] An example of the application and operation of this nozzle drive device 1 will be described. The nozzle drive device 1 can be used in combination with the workpiece conveying device disclosed in the aforementioned Patent Document 1 (Japanese Patent Application Publication No. 2024-147446). The workpiece conveying device 70 is positioned at the outlet 72 of a parts feeder that conveys a plurality of workpieces W in a linear manner, and is configured to receive the workpieces W on the parts feeder and rotate their orientation. The workpiece conveying device has a disc-shaped index table 74 whose rotation axis is inclined at 45 degrees with respect to the horizontal plane. The index table has a plurality of protrusions arranged at equal intervals in the circumferential direction, and pockets 76 for storing workpieces are formed between adjacent protrusions. Workpieces that enter the pockets 76 are vacuum-suctioned within the pockets. For details of the configuration of the workpiece conveying device 70, please refer to Patent Document 1.

[0040] The suction nozzle 30 of the nozzle drive device 1, schematically shown in Figure 5, descends from a position slightly higher than the workpiece W located in the pocket 76 at the lowest position of the intermittently rotating index table 74 (this corresponds to the upper limit position of the suction nozzle 30), makes contact with the workpiece and simultaneously suctions it, and then pushes the workpiece out of the pocket by descending further from this state.

[0041] The suction nozzle 30 descends further, placing the workpiece into a predetermined recess 61 of the storage member 60 positioned directly below it, and simultaneously releasing the suction from the workpiece. At this point, the position of the suction nozzle 30 corresponds to its lower limit position. After that, the suction nozzle 30 returns to its upper limit position. When the index rotation of the index table positions the adjacent pocket directly below the suction nozzle 30, the workpiece is similarly removed from that pocket.

[0042] The disclosed embodiments are non-limiting and preferred, and are not limited thereto. The above embodiments can be modified as appropriate without departing from the scope of the claims. [Explanation of Symbols]

[0043] Double job 1. Nozzle drive device 10 frames 16 Linear bearings (linear bushings) 16,23 Guide structure 18. Proximity Sensor 20 Nozzle holding structure 21 Upper member 22 Lower part 23 Linear shaft 24 Spherical bearings 26 Ball Club 27 Holes in the ball section 28 End face of the ball portion 30 Suction Nozzles 40 Actuators 42 Drive shaft 46 colors 50 Compression spring

Claims

1. In a nozzle drive device, Frame and, A nozzle holding structure having an upper member and a lower member connected to each other, and guided to move up and down relative to the frame via a guide structure, A suction nozzle for adsorbing a workpiece is attached to the lower member of the nozzle holding structure, An actuator attached to the frame, having a drive shaft that penetrates the upper member of the nozzle holding structure in the vertical direction and is movable up and down, A collar is attached to the drive shaft so as to be located below the upper member of the nozzle holding structure, and contacts the upper member to support the upper member from below, A compression spring is interposed between the frame and the nozzle holding structure, which is compressed when the nozzle holding structure rises and extends when the nozzle holding structure descends. Equipped with, A nozzle drive device configured such that when an upward impact load is applied to a workpiece while it is being held by the suction nozzle, the compression spring is compressed and the upper member of the nozzle holding structure separates from the collar, thereby cushioning the impact on the workpiece.

2. The nozzle drive device according to claim 1, wherein the guide structure includes a linear shaft connecting the upper member and the lower member of the nozzle holding structure, and a linear bearing provided on the frame that guides the linear shaft so as to be movable in the vertical direction.

3. The upper member of the nozzle holding structure has a spherical bearing. The drive shaft of the actuator is passed through a hole that penetrates the ball portion of the spherical bearing, and a gap is provided between the drive shaft and the hole. The end face of the ball portion contacts the collar, thereby supporting the nozzle holding structure with the collar. The nozzle driving device according to claim 1.

4. The nozzle drive device according to claim 1, further comprising a proximity sensor for detecting when the workpiece held by the suction nozzle has descended appropriately to a target position, wherein the proximity sensor is fixed to the frame and is provided to detect the proximity of the nozzle holding structure.

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