JP2003340767A - Output device with buffer function - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a compact output device of a simple structure with buffer function. <P>SOLUTION: In this output device 1 with buffer function, a cylindrical movable side permanent magnet 7 is fixed to an output rod 3 protruded from a device body 2 and inserted therein, a cylindrical fixed side permanent magnet 8 is fixed in a hole of the device body 2, a magnetic spring 10 is constituted of these permanent magnets, and power transmission members 13 and 14 which are fitted to a rotary shaft 12a of a motor 12 fixed to the device body 2 to change a point of application in the moving direction of the output rod 3 control the point of application with respect to a power receiving member 11 fixed to the output rod 3. <P>COPYRIGHT: (C)2004,JPO

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention is provided with a suction pad, for example, and is used for pressing a suction pad against an object arranged at a predetermined position, and an output which gives a reciprocating linear motion in such a predetermined work. The present invention relates to a device, and more particularly to an output device with a cushioning function, which is provided with a cushioning mechanism for cushioning an impact with an object that receives a linear motion.

[0002]

2. Description of the Related Art When a small precision component such as an IC chip is transferred, a method of sucking and holding an object to be conveyed on a suction pad is adopted, but the suction pad is transferred while the robot arm or the like remains moving. If it is pressed against an object, the output of the motor acts as it is, and there is a danger that it will be damaged due to excessive force. Therefore, the suction pad is attached to the output device with a buffer function, and the suction pad is pressed against the transported object by the buffer function of the device.

To this end, for example, an output device with a buffer function (hereinafter, simply referred to as “output device”) 100 shown in FIG.
Then, a cylinder is used to obtain a stroke in the axial direction, and when the buffer 105 is lowered to press the suction pad 106 against the object to be conveyed, the impact is moderated by absorbing the load. The output device 100 has a built-in cylinder in which a piston rod 102 is projected downward in a device body 101, and an L-shaped slider 103 that slides along a guide due to expansion and contraction of the piston rod 102.
In addition, a buffer 105 for absorbing shock is attached.

When the object to be conveyed is sucked and held, for example, the output device 100, which is horizontally moved in the posture shown in the figure, is stopped at a predetermined position, and then the piston rod 102 is extended so that the suction pad 106 becomes the object to be transferred. Press against. At that time, even if the transported object is located at a position higher than expected, the buffer 105 absorbs an excessive pressing reaction force, and an excessive force applied to the transported object can be suppressed. For such a buffer 105, for example, a magnetic spring device disclosed in Japanese Patent Laid-Open No. 2002-054671 proposed by the present applicant is effective. However, in the output device 100 using such an air cylinder, it is difficult to finely adjust the expansion and contraction of the piston rod 102.

Therefore, as an alternative to the cylinder,
It is conceivable to use the actuator shown in FIG. 6 and thereby configure an output device. Actuator 20
In the case of 0, the ball screw 201 is rotated by a stepping motor or a servomotor, and the slider 203 is linearly moved along the linear guide 204 by feeding the ball nut 202 screwed into the ball screw 201. Therefore, the feed amount of the slider 203 can be accurately adjusted by the rotation of the motor, and the buffer 10 can be adjusted in the same manner as the slider 203 shown in FIG.
By attaching 5, it is possible to configure an output device that alleviates the impact on the transported object when a linear motion is output.

[0006]

However, in each of the conventional output devices 100 and 200, the linear movement of the sliders 103 and 203 is output by the driving of the cylinder or the motor, and the object to be conveyed is transmitted through the sliders 103 and 203. Since the buffer 105 is attached to a portion such as an object that directly acts on the work target, the number of parts is large and the structure is complicated. Further, it is difficult to reduce the size of the device itself.
Further, the output devices 100 and 200 are provided with the sliders 103 and 203 and the buffer 105 in order to obtain a high straightness in the movement of the suction pad 106 that directly acts on the work object.
Precise processing is required at two places, the part and the manufacturing cost, and the structure is difficult to achieve straightness.

SUMMARY OF THE INVENTION Therefore, an object of the present invention is to provide a compact output device with a shock absorbing function, which has a simple structure in order to solve such a problem.

[0008]

According to an output device with a cushioning function of the present invention, a cylindrical movable permanent magnet is attached to an output rod projectingly inserted into the device main body, and an output device main body in which the output rod is inserted. A cylindrical fixed-side permanent magnet is fixed in the hole of, and a magnetic spring is constituted by both permanent magnets, and is attached to the rotating shaft of the motor fixed to the main body of the device, and the action point is set in the moving direction of the output rod. It is characterized in that the power transmission member to be changed is a power receiving member fixed to the output rod, the operating point of which is applied from the output side.

According to the present invention, the action point of the power transmission member changes in the moving direction of the output rod due to the rotation of the motor,
The power receiving member receives the change and moves the output rod in the axial direction. Specifically, the attractive force of the magnetic spring acts in the protruding direction, the output rod is ejected by the movement of the power receiving member following the power transmission member, and the protrusion is returned against the attractive force. Be done. Therefore, a magnetic spring that exerts a buffering function is directly formed on the output rod, and the transmission path from the motor to the output rod is short, so that the structure of the device can be made simple and compact.

Further, in the output device with a cushioning function according to the present invention, the power transmission member is fixed to the output rod so that the attraction force of the magnetic spring always acts on the output rod in the protruding direction. The movable side permanent magnet is applied to the power receiving member at a position displaced from the fixed side permanent magnet in the anti-projection direction.

The magnetic spring has a range in which a constant attractive force is obtained regardless of the amount of displacement of the permanent magnet. Therefore, in the present invention, the power transmission member is applied to the power receiving member fixed to the output rod so that the movable side and fixed side permanent magnets are in a relationship to generate such an attraction force so that only that range is used. ing. Therefore, according to the present invention, it is possible to always output an appropriate pressing force by eliminating insufficient pressing or conversely pressing too much.

According to an embodiment of the present invention, for example, the power transmission member has a roller supported at one end of a roller plate fixed to a rotation shaft of a motor, and the power receiving member is the A power receiving plate having a contact surface perpendicular to the output rod, wherein the roller is applied to the contact surface of the power receiving plate from the output side. According to the present invention, the displacement in the moving direction of the output rod in the roller draws a sine wave, and the angular resolution of the output shaft can be made even more precise, so that the position adjustment of the output rod and the repeat stop precision are realized with a high resolution. can do.

[0013]

BEST MODE FOR CARRYING OUT THE INVENTION Next, an embodiment of an output device with a buffer function according to the present invention will be described below with reference to the drawings. FIG. 1 and FIG. 2 are structural views showing an embodiment of an output device with a cushioning function in a partial cross section, each showing a different operation state. The output device with a buffer function (hereinafter, simply referred to as “output device”) 1 is configured such that an output rod 3 is passed through a device body 2 and a rotational movement of a motor is converted into a reciprocating linear movement of the output rod 3. .
In the following description, the upper and lower sides of the output device 1 are referred to as the upper and lower sides for convenience sake.

The apparatus main body 2 has a shape as shown in FIGS. 1 and 2, and one output rod 3 is passed through the notch 2a formed in a U shape. There is. Output rod 3 through two through holes 2b and 2c
Forms a spline shaft in which a ball starting groove is formed, and its rotation is restricted by the ball splines 5 and 6 fitted in the through holes 2b and 2c, respectively. Then, the magnetic spring 10 that applies a spring force to the output rod 3
Is provided.

The magnetic spring 10 includes an output rod 3 and a through hole 2.
The movable-side or fixed-side cylindrical magnets (permanent magnets) 7 and 8 are fixed to a. The magnets 7 and 8 have the same length and are formed with diameters that can be overlapped coaxially in a non-contact state,
Magnetic poles having different N poles or S poles are magnetized on the opposing surfaces. Therefore, in the magnetic spring 10, the magnets 7 and 8 attract each other, and the forces involved in the axial direction are balanced with both ends overlapping. In the output device 1, the suction force that is generated when trying to return it to the balanced state with respect to the axial shift is used as a spring force, and serves as a cushioning means for absorbing the shock applied to the output rod 3.

Next, the output rod 3 provided with the magnetic spring 10
The power receiving plate 11 is fixed at the notch 2a. As shown in FIG. 3 showing the output device 1 of FIG. 1 in the AA cross section, the power receiving plate 11 extends parallel to the recess 2d side formed in the device main body 2, and the output rod 3 extends in the recess 2b. It is designed to move in parallel with the movement of. A through hole 2e is formed in the recess 2d of the device main body 2 rod 32, and a rotary shaft 12a of the stepping motor 12 fixed to the back surface is provided at the center of the through hole 2e. In the through hole 2e, the roller plate 13 is fixed to the rotary shaft 12a of the stepping motor 12, and the roller 14 is pivotally supported at one end thereof. Therefore, when the roller plate 13 is rotated by the driving of the stepping motor 12, the roller 14 moves on the predetermined circumference accordingly.

The roller plate 13 has a concave portion 2 on its upper surface.
The recess 2 is formed so as to have almost the same height as the bottom surface of d.
It does not interfere with the power receiving plate 11 that moves in d, and the roller 14 attached thereto has the recess 2
protruding into d. The roller 14 and the power receiving plate 11 thus arranged in the recess 2d are located below the power receiving plate 11, that is, the output rod 3
It is located on the protruding side of.

The power receiving plate 11 is abutted against the roller 14 at the position shown in FIG. 1 to take a descending end, and is prevented from further descending. The magnetic spring 10 is attached in such a position that the movable-side magnet 7 is displaced upward with respect to the fixed-side magnet 8, and the attraction force acts on the output rod 3 on the lower side which is always projected. It is supposed to do. Therefore, the power receiving plate 11 is constantly pressed against the roller 14 side, and the heights of the power receiving plate 11 and the output rod 3 change following the movement of the roller 14.

The downward projection amount of the output rod 3 in the output device 1 depends on the moving position of the roller 14 applied via the power receiving plate 11 fixed to the output rod 3, that is, the rotation angle amount of the stepping motor 12. Controlled. Therefore, as shown in FIG. 1, the roller plate 13 becomes vertical, and the output rod 3 is most protruded when the roller 14 takes the descending end. Then, if the angle of the roller plate 13 is changed by the stepping motor 12 from there, the position of the roller 14 is raised, and the output rod 3 is
It is pushed up against the attractive force of the magnetic spring 10. Then, as shown in FIG. 2, when the roller 14 is rotated 180 °, the roller 14 takes the rising end, and the output rod 3 is in the most retracted state.

By the way, in this embodiment, the suction pad 21 is attached to the lower end of the output rod 3, and the output device 1 is used as a transfer device as in the conventional example. That is, the output rod 3 is a hollow pipe, and the tube 23 is connected through the connecting block 22 at the other end.
3 is configured to be connectable to the suction pump side (not shown) connected via the port 24 of the apparatus main body 2.
Therefore, if the suction surface of the suction pad 21 is applied to and sucked by the transported object, the transported object is evacuated and the suction pad 2
1 is adsorbed on the sheet 1, and is moved to a predetermined position by moving the output apparatus 1 as it is. As such a case, for example, there is a case where IC chips are sequentially taken out from a tray type chip storage place.

In this way, the transfer device including the output device 1
When the C chip is held by suction, for example, the output device 1 is moved to a predetermined position by another transfer device or the like. Then, as shown in FIG. 2, the output rod 3 is pulled up, and the suction pad 21 is not in contact with the IC chip and the output device 1
Then, the rotation of the stepping motor 12 is adjusted so that the output rod 3 is projected downward by a predetermined amount and the suction pad 21 is brought into contact with the IC chip to be held by suction. Then, the IC chip can be taken out by operating in the state shown in FIG.

In the output device 1, in such a case, the attraction force of the magnetic spring 10 acts as a spring, and the attraction force pushes the suction pad 21 against the object. At this time, since the magnetic forces of the magnets 7 and 8 obtain a constant attractive force regardless of the amount of axial deviation, the IC chip will not be pressed by an excessive force no matter how much the output rod 3 is pushed. Therefore, even if the tray is warped or the IC chip is higher than the expected position, the suction pad 21 is pressed against the IC chip with the same force as when the IC chip is at the correct height. Further, since the stroke range of constant thrust is wide, even if the stroke position of pressing the suction pad 21 against the IC chip varies, insufficient suction or conversely excessive pressing can be avoided, and the suction pad 21 can always be pressed with an appropriate pressing force. It can be pressed against the IC chip.

FIG. 4 is a graph showing the characteristics of the stroke and thrust of the magnets 7 and 8, and shows the state where the magnets 7 and 8 are overlapped as zero stroke. The magnetic spring 10 includes a magnet 7 that is displaced in the axial direction,
8, the suction force became substantially the same during a predetermined stroke as shown in FIG. And, it was almost the same value at the time of pulling to increase the axial displacement of the magnets 7 and 8 and on the contrary when pressing the object when returning.

In the output device 1, the stroke range from the stroke 0 to S is used so that a constant spring force always acts in the axial direction of the output rod 3 by utilizing the region of the stroke where the suction force is stable.
The spaces are kept unused. That is, as described above, the displacement of the magnets 7 and 8 is provided at the descending end applied to the roller 14 at the position shown in FIG. 1, and the displacement amount is the distance corresponding to the strokes 0 to S. Thus, by making the attraction force of the magnetic spring 10 constant, when the output rod 3 is moved up and down against the attraction force, the force is smoothly transmitted from the rotational movement of the stepping motor 12 to the linear movement of the output rod 3. You will be able to.

In the output device 1, the output device 1
The resolution of height adjustment at the descending end and the ascending end becomes high, and the displacement speed decreases at the vertical position where fine adjustment is possible, and acceleration / deceleration is performed so as to increase the speed at the intermediate height where adjustment is unnecessary. Be seen. That is, when observing the rotation of the roller plate 13 with the horizontal position of the power receiving plate 11 orthogonal to the output rod 3 being 0 °, the height of the roller 14 attached to the tip of the roller plate 13 should change in a sin curve. And the roller 14 with respect to the rotation of the power receiving plate 11
The height displacement of is smaller at the upper and lower ends. For example, when this is shown by a specific numerical value, it is 0 when the roller plate 13 is horizontal.
The vertical displacement of the output rod 3 is 2.59 mm when rotated at 15 ° from the position of −90 ° or + 90 ° shown in FIG. 1 or 2. The vertical displacement is 0.3 when rotated by
It was 4 mm. Therefore, the suction position can be controlled with high accuracy by using the descending end or the ascending end.

Although the output device with a buffer function has been described with reference to the embodiment, the present invention is not limited to this, and various modifications can be made without departing from the spirit of the present invention. For example, in the above-described embodiment, the ball spline is provided in the through holes 2b and 2c so that the output rod 3 does not rotate, but the magnets 7 and 8 are provided to prevent the rotation.
By dividing the magnetic pole in the circumferential direction, it can function as a detent. Then, it is not necessary to provide a ball spline, and the cost can be reduced accordingly.

Further, in the above-described embodiment, a roller 14 is pivotally supported at one end of the roller plate 13 as a power transmission member, and the roller 14 is fixed to one side of the power receiving plate 11 fixed to the output rod 3. Alternatively, for example, an elliptical cam member may be used as the power transmission member, and the power transmission member may be applied to the cam follower pivotally supported by the power receiving plate 11.

[0028]

According to the present invention, a cylindrical movable permanent magnet is provided on an output rod inserted into a main body of the apparatus and a fixed permanent magnet having a cylindrical shape is provided in a hole of the main body into which the output rod is inserted. A power transmission member, which is fixed to the magnet and constitutes a magnetic spring by both permanent magnets, is attached to the rotary shaft of the motor fixed to the main body of the device and changes the point of action in the moving direction of the output rod is fixed to the output rod. Since the action point can be applied to the generated power receiving member from the output side, it is possible to provide a compact output device with a shock absorbing function having a simple structure.

[Brief description of drawings]

FIG. 1 is a structural view showing an embodiment of an output device with a cushioning function in a partial cross section when an output rod is projected.

FIG. 2 is a structural view showing an embodiment of an output device with a cushioning function in a partial cross section when the output rod is returned.

FIG. 3 is a view showing the output device with a cushioning function of FIG. 1 taken along the line AA.

FIG. 4 is a graph showing the measurement results of the characteristics of the stroke and thrust of the magnetic spring.

FIG. 5 is a diagram showing a conventional output device with a cushioning function at the time of returning.

FIG. 6 is a view showing a conventional output device with a cushioning function at the time of protrusion.

[Explanation of symbols]

1 Output device with buffer function 2 device body 3 output rod 7 magnet 8 magnets 10 magnetic spring 11 Power receiving plate 12 stepping motor 13 Roller plate 14 Laura

Claims (3)

[Claims] 1. A cylindrical movable permanent magnet is fixed to an output rod inserted into the main body of the apparatus, and a cylindrical permanent magnet is fixed inside a hole of the main body into which the output rod is inserted. , A magnetic spring is composed of both permanent magnets, and is attached to the rotating shaft of a motor fixed to the main body of the device.
The buffer function, wherein the power transmission member for changing the point of action in the moving direction of the output rod is one in which the point of action is applied to the power receiving member fixed to the output rod from the output side. Output device. 2. The output device with a cushioning function according to claim 1, wherein the power transmission member acts on the output rod so that the attraction force of the magnetic spring always acts on the output rod in a protruding direction. An output device with a cushioning function, wherein the movable permanent magnet is applied to a fixed power receiving member at a position displaced from the fixed permanent magnet in an anti-projection direction. 3. The output device with a shock absorbing function according to claim 1 or 2, wherein the power transmission member is a roller plate fixed to a rotation shaft of a motor and having a roller rotatably supported at one end thereof. Further, the power receiving member is a power receiving plate having a contact surface that is perpendicular to the output rod, and a roller is applied to the contact surface of the power receiving plate from the output side. Characteristic output device with buffer function.