JPH0539886U - Suction device with variable caliber - Google Patents

Abstract

(57) [Abstract] [Purpose] To provide a suction device with a variable opening diameter. [Structure] Concentric multiple cylinders that slide with each other are used as mouthpieces.
The outermost cylinder is joined to the cylindrical housing and forms a part of the case. A cylindrical fixed cam and a movable cam are arranged in an overlapping manner in the housing. The movable cam is driven by a motor to rotate. The shaft fixed to each inner cylinder passes through the corresponding spiral groove of the movable cam and engages with the cam groove of the fixed cam. A detection mechanism for detecting the rotation angle of the movable cam is provided. In addition to the opening of the multi-cylinder, the housing is provided with a hole for piping to the vacuum pump, and a power supply line to the motor and a wire from the previous detection mechanism are drawn out and hermetically sealed. [Effect] Various work sizes can be accommodated without replacing the suction device.

Description

[Detailed description of the device]

[0001]

[Industrial applications]

 The present invention relates to a device for sucking and handling a work in an assembly or palletizing work using a dedicated machine such as an electronic component mounting machine or a general-purpose robot.

[0002]

[Prior Art]

 The work performed by electronic component mounters and assembly robots (collectively referred to as robots below) involves lifting small workpieces such as ICs and chip resistors, moving them, and placing them at target locations. In that case, as an end effector for grasping the work, a device for adsorbing the work to a suction port connected to a vacuum pump is widely used.

For example, as shown in FIG. 8, when handling a large workpiece 100 such as PLCC, a cylindrical suction port 101 having a large diameter is used. At the time of adsorbing the work, the inside of the suction port 101 is depressurized by a vacuum pump connected to the tube 102. The end effector is attached to the hand attaching portion of the robot by the flange 103. Further, as shown in FIG. 9, a suction port 201 having a small diameter is used for a work 200 having a small chip resistance or the like. This is to cover all the mouthpiece openings, even for small workpieces. However, the suction force generated by the small-diameter suction port 201 is small, and is not sufficient to operate a large workpiece as shown in FIG. Therefore, it is necessary to properly use the suction port 101, the suction port 201, etc. according to the size of the work.

[0004]

[Problems to be solved by the device]

 Due to such circumstances, the size of the work that can be handled is limited by the robot having a configuration that does not have a method for selectively using the suction mouth. When the product is changed and the production equipment is to be changed over, it is necessary to prepare a new mouthpiece suitable for the new workpiece. This makes it impossible to automatically perform a setup change by computer management.

Further, in a robot having a so-called multi-head configuration having a plurality of suction holes as an end effector of the robot, the work to be handled is surely removed, but the movement target of the robot is changed for each suction port to be used. Since it has to be operated, the number of times of instruction is increased, and the end effector becomes large, there are inconveniences such as the movement speed cannot be increased and the movement is disturbed. Above all, there is the problem of having to prepare many heads. This cannot save labor in building the assembly system.

Further, in a robot equipped with a so-called hand changer that can automatically replace the end effector, the accuracy of assembly and palletizing is determined by the accuracy of hand replacement of the hand changer, which causes a decrease in accuracy. In addition, the time required to replace the hand increases the work time.

In order to solve these problems, an object of the present invention is to provide a suction device that can change the opening diameter of the suction port without replacing the device.

[0008]

[Means for Solving the Problems]

 In order to achieve the above object, the present invention is configured as follows. A plurality of cylinders are placed as concentric rings so that they can slide smoothly, and the outermost cylinder also serves as a case, forming a cylindrical housing that houses the cams, motors, etc. described later. Are combined. Inside the housing, a cylindrical fixed cam and a movable cam are placed in a stack. The fixed cam has a cam groove parallel to the cylindrical axis and is fixed to the housing. The movable cam has a plurality of spiral grooves respectively corresponding to those other than the outermost circumference of the multiple cylinders, and can be rotated by being driven by a motor. The movable cam is provided with detection means for detecting the rotation angle of the movable cam. Radially projecting shafts are fixed to the inner cylinders of the multiple cylinders, and these shafts engage with the cam grooves of the fixed cam through corresponding spiral grooves provided on the movable cam. . The housing is provided with a hole for piping to the vacuum pump, and the power supply line to the motor and the wiring from the detection means are exposed to the outside and hermetically sealed.

[0009]

[Action]

 When the controller of the device controls the motor to rotate the movable cam, the inner cylinder is sequentially pushed out as the movable cam rotates. When a cylinder having a desired diameter is projected, the diameter of the mouthpiece can be selected by using this as a mouthpiece. Based on the information from the detection mechanism that detects the rotation of the movable cam, the controller knows the selected state of the mouthpiece.

[0010]

【Example】

 Hereinafter, an embodiment of the present invention will be described with reference to the drawings. FIG. 1 is a sectional view of a suction device according to the present invention in a standard state. Inside the cylinder 1, the cylinders 2, 3 and 4 whose diameters are gradually reduced are concentrically accommodated. The side surface of each cylinder is finished with high precision, plays the role of a linear bearing, and slides smoothly. The outermost cylinder 1 is connected to a cylindrical housing 22. The housing 22 is provided with a hole 18 for piping to a vacuum pump. Except for the hole 18 and the opening of the multi-cylinder, the housing has a closed structure. The cylinders 2, 3 and 4 are provided with brims 2a, 3a and 4a, respectively, facing outward. Reference numerals 15, 16, and 17 are O-rings for increasing airtightness when the cylinders move and the flanges overlap each other. A fixed cam 5 and a movable cam 7, both of which are cylindrical, are arranged so as to overlap between the collar and the housing. The cylindrical portion of the movable cam 7 is provided with three spiral through grooves 51, 52 and 53. Radially projecting shafts 19, 20 and 21 are fixed to the outer circumferences of the flanges of the cylinders 2, 3 and 4, and these shafts pass through the corresponding spiral grooves of the movable cam 7 and are fixed. It is engaged with the cam groove 61 of the cam 5. Therefore, the cylinders 2, 3 and 4 are prevented from rotating by the fixed cam 5.

At the end of the movable cam 7, there is a flange 7a toward the inside, and an internal gear is provided on the inner circumference of the flange 7a. A gear 12 attached to the output shaft of the motor 11 meshes with this internal gear, and the rotation of the motor 11 causes the movable cam 7 to rotate. The motor 11 is fixed to the housing 22 by a mounting member 13. The lead wires 29, 30 of the motor 11 are connected to the external contacts 33, 34. The motor 11 has a structure in which a break is applied except when power is supplied.

When the collar 7a of the movable cam 7 is viewed from the direction of arrow A in FIG. 1, electrodes 71 to 74 are provided as shown in FIG. Each of the electrodes 71, 72 and 73 is an arc-shaped electrode whose end is defined as shown by the angle in the figure, and the electrode 74 is a circular ring whose entire circumference is connected. All electrodes are connected to each other at 180 °. The leaf spring contacts 23 to 26 that come into contact with these electrodes are fixed to the housing by the mounting member 14 at the position opposite to the shafts 19 to 21 in the reference state of FIG. Connect to external contacts 35-38.

The rotation angle of the movable cam 7 can be detected by checking whether the external contacts 35 to 37 are electrically connected to the common contact 38. In this embodiment, since the conduction state changes every 90 °, the position every 90 ° can be known.

As described above, the shafts 2a, 3a, 4a fixed to the cylinders 2, 3, 4 are engaged with the grooves 51, 52, 53 of the movable cam 7, and the cylinders 2-4 are movable. It is pushed to the left in the figure as the cam rotates. FIG. 2 is an expanded view of the cylindrical surface of the movable cam, and reference numerals 51, 52 and 53 are spiral grooves. On the other hand, the cam groove 61 of the fixed cam 5 is a straight line parallel to the cylinder axis, and similarly, when the cylinder surface is expanded, it becomes as shown in FIG. In FIG. 2, the horizontal axis represents the circumferential direction and the vertical axis represents the cylindrical axis direction. In the reference state of FIG. 1, the shafts 19, 20, 21 are at the 0 ° position at the left end of the movable cam development view, the cylinders 2, 3, 4 are in the most retracted state, and the cylinder 1 serves as a suction port. When the movable cam rotates and the shafts 19, 20, 21 come to the position of 90 °, the cylinder 2 becomes the most protruded state and becomes a mouthpiece (Fig. 5), and at the position of 180 °, the cylinder 3 becomes. At the most protruding position (Fig. 6), the cylinder 4 is most protruding at the 270 ° position (Fig. 7). In the state of FIG. 7, the O-rings 15, 16 and 17 of FIG. 1 prevent air from leaking from the gap between the cylinders.

Next, a method of selecting a mouthpiece will be described. When the cylinder 1 is used as a suction port, the movable cam 7 is rotated by the motor 11 so that the shafts 19, 20 and 21 are located at the angle 0 ° of the movable cam spiral groove in FIG. As described above, since the shafts 19, 20, 21 are engaged with the cam groove 61 of the fixed cam 5 and are prevented from rotating, the cylinders 2, 3, 4 do not rotate even if the movable cam 7 rotates. Instead, they are pushed by the spiral grooves 51, 52, 53 of the movable cam 7 and slide in the axial direction of the cylinder. The fact that each shaft is at the 0 ° position can be confirmed by detecting that all the external contacts 35 to 37 start conducting with the common contact 38 while rotating the movable cam.

When the cylinder 2 is used as the mouthpiece, the movable cam 7 is rotated by the motor 11 so that the axes are located at 90 ° in FIG. The fact that the axis is at 90 ° can be confirmed by detecting the start of conduction of the external contact 35 with the common contact 38 while rotating the movable cam.

When the cylinder 3 is used as the suction port, the movable cam 7 is rotated so that each shaft is located at 180 ° in FIG. The fact that the shaft is at 180 ° can be confirmed by detecting the start of conduction of the external contact 36 with the common contact 38 while rotating the movable cam.

When the cylinder 4 is used as the mouthpiece, the movable cam 7 is rotated so that each axis is located at 270 ° in FIG. The fact that the axis is at 270 ° can be confirmed by detecting the start of conduction of the external contact 37 with the common contact 38 while rotating the movable cam.

Although the configuration and operation of the present embodiment have been described above, the present invention is not limited to these configurations. For example, increasing the number of multiple cylinders and changing the motor system to an ultrasonic motor It is possible to change the shape of the cylinder into a donut shape and change the cross-sectional shape of the cylinder into a polygon. Further, if the cylinder is a cylinder having a polygonal cross section, the fixed cam 5 serving as a whirl stop is unnecessary.

[0020]

[Effect of the device]

 In the suction device according to the present invention, since the suction port of the multi-cylinder can be selected from the outside by controlling the suction port diameter, it is not necessary to prepare another type of suction device tool when the setup is changed due to the change of the product. Also, when managing production equipment with a computer, setup can be automatically changed. The flexibility of the system can be secured without preparing a lot of equipment, so the labor required for constructing the assembly system can be saved. Since it is not a complicated mechanism like a hand changer, it can secure positional accuracy and the center position of the cylinder does not change regardless of which cylinder is selected.

[Brief description of drawings]

FIG. 1 is a cross-sectional view showing an embodiment of the present invention in a state in which the mouthpiece diameter is maximum.

FIG. 2 is a development view showing the shape of a spiral groove of a movable cam according to the present invention.

FIG. 3 is a development view showing a shape of a cam groove of a fixed cam according to the present invention.

FIG. 4 is a view showing the shape of electrodes on the end surface of the movable cam according to the present invention.

FIG. 5 is a sectional view showing a state in which a second mouth diameter is selected in the embodiment of the present invention.

FIG. 6 is a sectional view showing a state in which a third suction port diameter is selected in the embodiment of the present invention.

FIG. 7 is a sectional view showing a state in which a fourth suction port diameter is selected in the embodiment of the present invention.

FIG. 8 is a diagram showing an example of a conventional suction device when a work is large.

FIG. 9 is a diagram showing an example of a conventional suction device when a work is small.

[Explanation of symbols]

 1, 2, 3, 4 Cylindrical 5 Fixed cam 7 Movable cam 11 Motor 19, 20, 21 Shaft 23, 24, 25, 26 Contact 51, 52, 53 Spiral groove 61 Cam groove 71, 72, 73, 74 Electrode

Claims (2)

[Scope of utility model registration request] 1. In a suction device for sucking an object into the tubular mouth by lowering the fluid pressure inside the tubular mouth below the pressure outside, a plurality of tubular mouths having different diameters are concentrically multiplexed. A suction device having a variable caliber, characterized in that it is provided with a means for relatively moving each cylindrical mouth in the axial direction, and one of the plurality of cylindrical mouths is selected as a suction mouth. 2. A plurality of cylindrical ports having different diameters are concentrically arranged so as to be axially slidable relative to each other to form a suction port, and the outermost cylinder of the multiple cylinders is connected to a housing. Forming a part of the case, and arranging a cylindrical fixed cam and a movable cam in an overlapping manner in the housing, and the fixed cam has a cam groove parallel to the cylindrical axis and is fixed to the housing. The cam has spiral grooves corresponding to cylinders other than the outermost one among the multiple cylinders, and the plurality of spiral grooves relatively move each cylinder in the axial direction as the movable cam rotates. There is provided a motor for driving and rotating the movable cam, and the cylinders other than the outermost one of the multiple cylinders are fixed with shafts projecting outward, and the shafts are spiral grooves of the movable cam. And engaging with the cam groove of the fixed cam, The detecting means for detecting the rotation angle of the movable cam is provided, and the housing is hermetically sealed so as to prevent fluid from leaking from other than the holes for the suction port and the pipe, and the power feeding line to the motor and the movable cam rotation angle detecting means. A suction device having a variable caliber in which one of the plurality of cylindrical mouths is selected as a suction mouth by providing an electrical contact to which a wire is connected.