JP4416697B2 - Clamping device - Google Patents

Description

This invention relates to a clamp equipment at the time of transporting the various weight, etc., it relates that enhance versatility and to freely change the clamping position against particularly between different work.

Clamp devices that can adjust the clamp position are known. For example, a clamp device provided at both ends of a linear support member can be freely adjusted (see Patent Document 1), or a plurality of circles having different diameters. In order to deal with plate-like workpieces, there is a type in which a disk-like jig is divided into a plurality of pieces so that the radial clamp position is variable (2).
JP 2000-176757 A JP 2000-015588 A

In each of the above prior arts, the clamp point is limited to a workpiece with two clamp points or a clamp with respect to a circular workpiece. However, such a clamp cannot be applied to a workpiece that is indefinite, such as a complex shape, and has a plurality of clamp points of 3 or more, and a dedicated clamp device with a fixed clamp position for each workpiece is used. Capital investment has increased in the mass production form that is required to be provided, has low versatility, and is produced in a variety of small quantities.
Therefore, it has been demanded to improve versatility by making it possible to freely change the clamp position even for a workpiece having such an indefinite shape and a clamp point of 3 or more. The present invention aims to realize such a demand.

The invention according to claim 1 of the present invention relates to a clamping device in which the position of the clamp supported by the clamp support tool is adjusted so that it can be clamped to a plurality of workpieces having different clamping points.
The clamp support tool is provided with slider arms extending radially from the center of the tool, which is the center thereof, as many as the number of clamp points, sliders are provided on the slider arms so as to be adjustable and movable in the longitudinal direction, and a clamp is provided on each slider. With
The tool center point is made to coincide with the clamp center point that is the intersection of a plurality of straight lines that pass through each clamp point of the work and that coincides with the open angle of the adjacent slider arm, and each slider arm corresponds to To match or have a predetermined relationship with the straight line, and by adjusting and moving each slider in the longitudinal direction of the corresponding slider arm, the clamp is positioned on the corresponding clamp point ,
The clamp point is a plurality of holes of three or more points, at least one of which is provided in advance on the workpiece so as not to be positioned on one concentric circle centered on the clamp center point,
The workpiece is supported by inserting each clamp into each of the holes .

  Here, matching each slider arm with the corresponding straight line means a state in which each slider arm overlaps with the corresponding straight line in a plan view, and performing a predetermined relationship means that the slider arm corresponds to each slider arm. A straight line means a state in which the straight lines are parallel to each other without overlapping or have a predetermined opening angle.

The invention of claim 2 comprises the clamp part according to claim 1 , wherein the clamp is expanded and contracted in a contracted state and a swelled state, and is put into the hole of the clamp point in the contracted state, and then swelled. It is characterized by being in a clamped state in close contact with the inner wall of the hole at the clamp point.

According to a third aspect of the present invention, in the above-mentioned second aspect , the clamp part is formed in a cylindrical shape made of an elastic member, and when a wire connected to the bottom part of the clamp part is pulled, the intermediate part of the clamp part is radially outward. When the wire swells and loosens, it is restored by the self-elasticity of the clamp part, and the swelled part contracts.

According to a fourth aspect of the present invention, in the first aspect , the clamp has a hook shape that opens and closes a tip, and the tip is engaged with the workpiece by opening the tip when it is out of the reference hole.

A fifth aspect of the present invention is characterized in that, in the second aspect , the clamp portion is formed in a bag shape made of an elastic body, and is expanded or contracted by injecting or discharging a fluid into the clamp portion forming the bag shape.
A sixth aspect of the present invention is characterized in that, in the first aspect, a hole for which a use other than clamping, such as fastening at the time of assembly, is determined in advance is used as the hole forming the clamp point.

According to the present invention, it is possible to obtain the clamp center, and positional information about known clamping point by the real measurement, etc., by calculation based on the opening angle of the adjacent slider arm. Therefore , when the slider is adjusted and moved so that the distance between the tool center points of each clamp matches the distance from the clamp center point to the corresponding clamp point, the tool center point of the clamp support tool 1 is made to match the clamp center point. Then, the position of each clamp can be easily adjusted so as to coincide with the corresponding clamp point.

  Therefore, it has a plurality of clamp points of three or more points, and can be easily applied to various workpieces having different clamp points such as indefinite shapes, and the versatility of the clamp support tool can be improved. Since it is not necessary to dedicate each work, capital investment can be reduced.

Also, it is possible to easily clamp even workpieces where 3 or more clamp points are not located on a single concentric circle centered on the clamp center point and the clamps cannot be placed equidistant from the tool center point. Become.

Furthermore, the determination of the clamping center point, by their respective automated positioning of the clamp, the clamp position adjustment of the clamp support tool is facilitated and speed.

In addition, by aligning the tool center point of the clamp support tool with the clamp center point, each slider arm is passed over or to a position having a predetermined relationship with each clamp point, and the slider on each slider arm is adjusted and moved. Each clamp can be matched to a corresponding clamp point.

Moreover, the whole apparatus can be made compact by using the hole provided in the workpiece | work as a clamp point. Furthermore, if a hole for another purpose is used in advance, it is not necessary to provide a special reference hole.

  An embodiment will be described below with reference to the drawings. FIG. 1 is a perspective view of a clamp support tool 1 according to an embodiment. The clamp support tool 1 includes three slider arms 3A, 3B, and 3C that are arranged radially from a central base 2, and the top of each. Three sliders 4A, 4B, and 4C that are movable in the axial direction, and clamps 5A, 5B, and 5C provided on the sliders 4A, 4B, and 4C, respectively, are provided.

  When the opening angles between the adjacent slider arms 3A, 3B, and 3C are α, β, and γ, in this embodiment, they are equiangular (120 °). The central axes in the longitudinal direction of the slider arms 3A, 3B, and 3C are C1, C2, and C3. The central axes C1, C2, and C3 intersect at the tool center point O1.

  A support shaft 6 concentric with the tool center point O1 is provided on the center base 2 so as to be rotatable relative to the center base 2, and the rotation of the center base 2 relative to the support shaft 6 can be locked or unlocked by the angular position lock 7. Yes. The upper end of the support shaft 6 is attached to a robot arm 8, and the entire clamp support tool 1 is freely moved in a three-dimensional direction by a robot (not shown).

  Each of the three clamps 5A, 5B, and 5C having a rod shape is fitted to three reference holes 11A, 11B, and 11C provided at the workpiece 10 at the tip end portions (described later) of the clamps 5A, 5B, and 5C. The workpiece 10 can be moved by clamping from the inside of 11B and 11C.

  For each of the reference holes 11A, 11B, and 11C, arbitrarily select three of the holes for which other uses other than the clamp are determined in advance, such as a through hole of a boss provided in advance in the workpiece 10, such as fastening at the time of assembly. Available. The positions of the clamps 5A, 5B, 5C on the clamp support tool 1 side are freely determined at any time according to the positions of the reference holes 11A, 11B, 11C.

  That is, the clamp support tool 1 is arranged on the workpiece 10 so that the central axes C1, C2, C3 of the slider arms 3A, 3B, 3C pass over the corresponding reference holes 11A, 11B, 11C, respectively. The sliders 4A, 4B, and 4C may be slid and adjusted in position so that the clamps 5A, 5B, and 5C are positioned on the corresponding reference holes 11A, 11B, and 11C.

  At this time, on the workpiece 10, three straight lines passing through the corresponding reference holes 11A, 11B, 11C in parallel with the central axes C1, C2, C3 of the slider arms 3A, 3B, 3C are a, b , C, these straight lines intersect at one point, and this point is set as a clamp center point O2. Further, the angles formed by the straight lines a, b, and c are the opening angles α, β, and γ, and are equal to each other (120 °).

  The clamp center point O2 in this embodiment is an intersection of three straight lines a, b, and c. Each straight line passes over the corresponding reference holes 11A, 11B, and 11C, but the clamp center point O2 is the center. When one concentric circle is assumed, the reference holes 11A, 11B, and 11C are not located on the concentric circle.

  That is, when the reference holes 11A, 11B, and 11C are positioned on one concentric circle, it is a very limited special case. In such a case, the slider holes 3A, 3B, and 3C are centered on the slider arms 3A, 3B, and 3C. It is clear that the clamps can be easily clamped by arranging the clamps 5A, 5B and 5C at equal distances. However, the present invention clearly shows that the present invention is not limited to such a special case, but also covers generalized cases in which the distances from the centers of the clamps 5A, 5B, and 5C are individually different.

  Since the clamp center point O2 corresponds to the tool center point O1, the tool center point O1 is on the clamp center point O2 and the center axes C1, C2, C3 are on the corresponding straight lines a, b, c. It is necessary to position the clamp support tool 1 so as to overlap. Therefore, the positions of the reference holes 11A, 11B, 11C and the clamp center point O2 must be obtained, and these are obtained by actual measurement or calculation.

  That is, the workpiece 10 includes set reference points 12 and 13, and is positioned and set on the work table 14 (see FIG. 2) at this point. Therefore, if these set reference points 12, 13 or any other point is used as the coordinate origin, the coordinate points of the reference holes 11A, 11B, 11C can be obtained in advance by a design drawing or actual measurement. In addition, since the opening angles α, β, and γ (each 120 °) of the three straight lines a, b, and c are known, they are easily determined by calculation.

  This calculation can be easily and automatically calculated by a preset calculation program by inputting the position information of each reference hole 11A, 11B, 11C and numerical values related to the opening angles α, β, γ to an appropriate computer, for example. . Reference numeral 15 in the figure denotes clamp center point determination means for performing such calculation.

  The data (coordinate data) such as the clamp center point determined by the clamp center point determining means 15 is input to the controller 16 of the entire clamping device and the controller 17 of the robot. The controller 15 controls an angle adjustment mechanism 18, a position adjustment unit 20, a positioning lock mechanism 30 (see FIG. 4 and the like), an operation of the clamp portion 33 (FIG. 6) and the like which will be described later. The robot controller 17 controls the robot arm 8. The clamp center point determining means 15 may be integrated with the controller 16.

  FIG. 2 is a plan view of the entire clamp apparatus, and the clamp support tool 1 moves between a position adjustment area 9 where the position adjustment unit 20 is arranged and a work area where the work table 14 is placed. That is, the clamp support tool 1 is moved to the work table 14 by the robot arm 8 after the positions of the clamps 5A, 5B, and 5C are set on the position adjustment unit 20 and the angle is adjusted, and the workpiece 10 is shown by a solid line. Move from position to virtual position.

  The position adjusting unit 20 has three position adjusting means 21 arranged radially at 120 ° intervals. The arrangement of the position adjusting means 21 corresponds to the clamp support tool 1 and is arranged so that the longitudinal axis is parallel to the axis C1, C2, C3 of each corresponding slider arm 3A, 3B, 3C. When the clamp support tool 1 is made to coincide with the position adjustment origin O3 (see FIG. 3), the position adjustment origin O3 overlaps with the clamp center point O1 and is adjusted to a predetermined initial angle around the axis of the support shaft 6. The slider arms 3A, 3B, 3C partially overlap with the corresponding position adjusting means 21.

  FIG. 3 is a perspective view showing the relationship between the clamp support tool 1 and the position adjustment unit 20, and FIG. 4 is a plan view thereof. As shown in FIG. 3, the position adjusting means 21 includes a substantially straight base case 22 and a ball screw 23 arranged in the longitudinal direction thereof. The opening angle formed between the axis lines of the ball screws 23 in the adjacent position adjusting means 21 coincides with the opening angle between the slider arms 3A, 3B, 3C.

  The ball screw 23 includes a nut 24 that moves in the axial direction on the ball screw 23, and a positioning pole 25 that has a lower end fixed to the nut 24 and extends in the vertical direction. One end of the ball screw 23 is rotated forward and backward by a step motor 26 provided at one end of the base case 22, and the nut 24 and the positioning pole 25 integrated therewith can be moved to a predetermined arbitrary position.

  In the illustrated position adjustment state, the clamp support tool 1 is lowered from the position adjustment origin O3. For example, the positioning pole 25 is placed on the pressing portion 32a provided in a part of the slider 4C (the same applies to other sliders). The upper end is pressed and the positioning pole 25 moves in the center direction, thereby moving the slider 4C toward the tool center point O1.

  When the clamp support tool 1 rises after adjustment and the tool center point O1 coincides with the position adjustment origin O3, the slider 4A, 4B, 4C is disengaged, and the position adjustment means 21 makes it impossible to adjust the axial position. The support tool 1 can be adjusted in angle.

  As shown in FIG. 4, the sliders 4A, 4B, and 4C are slidable in the axial direction over the slider arms 3A, 3B, and 3C, and have a built-in positioning lock mechanism 30 at a predetermined position. Can be locked and unlocked freely. The positioning lock mechanism 30 can employ various known types such as an electromagnetic type.

  The central base portion 2 of the clamp support tool 1 is provided with a gear 2a concentric with the tool center point O1, and the drive gear 18a of the angle adjusting mechanism 18 meshes with this, so that the clamp support tool 1 is attached to the support shaft 6. The angle can be adjusted by turning around the axis. This angle adjustment is performed with the angular position lock 7 unlocked. In the unlocked state, the clamp support tool 1 returns to the initial angle and adjusts the angle. When locked, the clamp support tool 1 is fixed at the adjusted angle. The angle adjustment mechanism 18 includes a step motor 18b for rotating the drive gear 18a by a predetermined angle and a cylinder 18c for moving these back and forth in the direction of the tool center point O1.

  FIG. 5 is an enlarged view of the slider 4A portion (the same applies to other sliders). A return mechanism 31 is provided at the end of the slider arm 3A, and when the lock is released by the positioning lock mechanism 30, the slider 4A is returned to a predetermined home position that is the end of the slider arm 3A. The return mechanism 31 is, for example, a mainspring mechanism, and the slider 4A pulls out the mainspring 31a and moves in the center direction. Therefore, the slider 4A in this state is spring-biased in the return direction. Therefore, when the slider 4A is unlocked, it returns by winding the mainspring 31a. This return is instantaneous, and the return mechanism can be configured to be lightweight and inexpensive. However, various such return mechanisms 31 are possible.

  The slider 4A has a stay 32 extending downward from the slider arm 3A, and the upper end of the clamp 5A is attached to the lower end thereof. The distal end of the clamp 5A forms a clamp portion 33 that expands and contracts in the radial direction, and the expansion and contraction of the clamp portion 33 is performed by a cylinder 35 that is integral with the stay 32 via a wire 34. One end of the wire 34 is connected to an elastic member 36 provided in the cylinder 35 via a pulley 37.

  As is apparent from FIG. 6 which shows an enlarged view of this portion, the other end of the wire 34 is connected to the bottom 38 of the clamp portion 33 through the inside of the pipe-shaped clamp 5A. The clamp portion 33 has a cylindrical shape made of an elastic member such as rubber or urethane. When the bottom portion 38 is pulled upward by the wire 34, the length direction is compressed, and the intermediate portion swells outward in the radial direction. When loosened, the clamp part 33 is restored by its own elasticity, and the swollen part contracts and returns to the initial state.

  Therefore, when the cylinder 35 protrudes the telescopic member 36 toward the pulley 37, the wire 34 is loosened to bring the clamp portion 33 into an initial state and contract to be smaller than the hole diameter of the reference hole 11A. The unclamped state is not in contact with the inner wall of 11A. On the contrary, when the telescopic member 36 is retracted, the wire 34 is pulled up, the bottom 38 is pulled up, the middle portion in the longitudinal direction of the clamp portion 33 is expanded outward, and is in close contact with the inner wall of the reference hole 11A. Become.

In addition, this clamp part structure is an example, Comprising: A thing with the same effect is well-known, These can be selected suitably. For example, as a general mechanical type, there is a hook shape whose tip is opened and closed , which is inserted into a reference hole in a closed state, and then engaged by opening the tip when it comes out of the reference hole. .
Also, the clamp part is provided with a slit in the length direction so that it can be freely opened and closed, and the operating member for opening and closing the opening and closing part is operated by a driving member such as a motor or solenoid connected by a rod. It may be.
Further, the clamp portion may be formed into a bag shape made of an elastic body, and the fluid may be expanded or contracted by injecting or discharging the fluid.
Also, if the workpiece is relatively light, the clamp part is formed in a simple elastic block shape such as rubber or urethane, and this is moved into and out of the reference hole by a drive member such as a motor or solenoid connected by the rod. The clamp portion may be elastically deformed forcibly and the clamp portion may be pressed into the reference hole for press-fitting.

  Next, the clamping operation will be described. FIG. 7 is a flowchart at the time of clamp position control, and FIGS. 8 to 10 are diagrams showing the movement of the clamp support tool 1 in a plan view.

  First, the clamp support tool 1 is moved onto the position adjustment unit 20 by the robot arm 8, the tool center point O1 is positioned at the position adjustment origin O3 (S · 1), and the clamp support tool 1 is lowered from this state ( S · 2), a position where the upper end of each positioning pole 25 in the position adjustment unit 20 and a part of each slider overlap (S · 3), the angular position lock 7 is released (S · 4), and the positioning lock mechanism 30 is removed (S · 5).

  This state is the state shown in FIG. 8, and the sliders 4A, 4B, and 4C return to the home position that is one end of the slider arms 3A, 3B, and 3C, and the upper ends of the positioning poles 25 abut.

  Therefore, each positioning pole 25 is moved in the direction of the tool center point O1, the sliders 4A, 4B, and 4C are pushed in the direction of the tool center point O1 and moved to a predetermined position (S.6), and the positioning lock mechanism 30 is locked again. Positioning (S · 7). The movement of each positioning pole 25 is appropriately controlled by the controller 16 rotating the step motor 26 by a predetermined amount based on the output data calculated in advance by the clamp center point determination means 15.

  This state is the state shown in FIG. 9, and the distance between the sliders 4A, 4B, 4C and the clamps 5A, 5B, 5C from the tool center point O1 is the clamp center point O2 of the corresponding reference hole 11A, 11B, 11C. Is positioned so as to be the same as the distance from each other (the lengths of the line segments a, b, and c).

  Next, the positioning pole 25 is retracted (S · 8), the angle adjustment unit 18 is advanced and the angle is adjusted (S · 9 and S · 10). In this state, the adjustment angle position is again set by the angle position lock 9. Lock (S · 11). The controller 16 calculates the necessary rotation angle from the initial angle of the clamp support tool 1 at the adjustment position origin O3 based on the output data calculated in advance by the clamp center point determination means 15, and the step motor It is appropriately controlled by rotating 18b by a predetermined angle.

  This state is shown in FIG. 10, and if the tool center point O1 is made coincident with the clamp center point O2, the central axes of the slider arms 3A, 3B, 3C correspond to the straight lines a, b, It overlaps with c, and each clamp 5A, 5B, 5C becomes the positional relationship which overlaps with the respectively corresponding reference holes 11A, 11B, 11C.

Thereafter, the angular position lock 7 is retracted (S · 12), and the clamp support tool 1 is raised to a position of a predetermined height and returned to the origin (S · 13 and S · 14).
As a result, the positioning of the clamps 5A, 5B, and 5C in the clamp support tool 1 is completed. Thereafter, the clamp support tool 1 is advanced onto the central base 2 by the robot arm 8, and the tool center point O1 is set to the clamp center point. If it matches on O2, the tip of each clamp 5A, 5B, 5C matches the corresponding reference hole 11A, 11B, 11C A, B, C, so that the clamping work can be performed.

  Thus, according to this embodiment, the sliders 4A, 4B, and 4C are adjusted by determining the clamp center point O2 with respect to the three reference holes 11A, 11B, and 11C that are not on the same circumference. Can be clamped. Therefore, even if there is no dedicated clamp support tool 1 for each workpiece 10, it can be easily applied as long as the workpiece 10 has three reference holes 11A, 11B, and 11C. Cost can be reduced.

  In addition, the positions of the sliders 4A, 4B, and 4C are calculated, and the axial positions of the clamps 5A, 5B, and 5C and the rotation angle W of the clamp support tool 1 can be automatically set. It is very easy to change settings.

  Moreover, since the position adjusting unit 20 is provided, it is not necessary to provide an actuator such as a step motor or cylinder on the slider arms 3A, 3B, 3C, so that the clamp support tool 1 can be reduced in weight and can be easily operated by the robot. To do. Further, since the clamps 5A, 5B, and 5C are clamped in the reference holes 11A, 11B, and 11C, unlike the clamp that clamps the outside of the workpiece 10, the whole can be made compact.

  Further, the number of slider arms 3A, 3B, 3C is arbitrary as long as it is a plurality of 3 or more, and the opening angle between the slider arms 3A, 3B, 3C is not limited to an equal angle, but may be an arbitrary angle. However, by providing three slider arms 3A, 3B, and 3C at intervals of 120 °, the workpiece 10 can be conveyed in a balanced manner with a small number of slider arms 3A, 3B, and 3C.

  FIG. 11 is a diagram corresponding to FIG. 1 according to another embodiment. In this example, the angle adjusting mechanism 18 is integrally provided on the central base 2, and the ball screw 23 and the step motor 26 that form the position adjusting unit 20 are directly provided on the slider arms 3A, 3B, and 3C, respectively. The clamps 5A, 5B, and 5C corresponding to the lower portions of the cylinders 40A, 40B, and 40C that are adjusted and moved are integrated so that each of them can be expanded and contracted in the vertical direction. In this way, the angle adjustment mechanism 18 and the position adjustment member 21 can be integrated with each other by the four-axis configuration.

In addition, this invention is not limited to the said Example, A various deformation | transformation and application are possible. For example, in the above embodiment, there are three slider arms, 3A, 3B, and 3C, and each of them is arranged radially at 120 ° intervals, but this number is free, and a plurality of three or more are used. Can do. Further, the structure can be simplified if the opening angles are made equal, but the opening angles are not necessarily required and can be set freely. Moreover, the workpiece | work 10 in an Example is an illustration, It can apply by adjusting a clamp position easily and rapidly also with respect to a workpiece | work with a shape and the position of a clamp point. Further, the clamp point may not be a hole, but may be an external part of the work and may be clamped from the outside of the work.

The perspective view of the clamp support tool which concerns on an Example Top view showing how the clamp support tool is used Perspective view of position adjustment unit and clamp support tool The plan view Figure showing an enlarged view of a part of the slider Sectional view showing clamp structure Flow chart of position control Operation explanatory diagram of clamp support tool Same as above Same as above A perspective view of a clamp support tool according to another embodiment

Explanation of symbols

1: Clamp support tool 1, 2: Center base, 3A, 3B, 3C: Slider arm, 4A, 4B, 4C: Slider, 5A, 5B, 5C: Clamp, 10: Workpiece, 11A, 11B, 11C: Reference hole, 14: Work table, 15: Clamp center point determination means, 16: Controller, 18: Angle adjustment mechanism, 20: Position adjustment unit, 25: Positioning pole, 33: Clamp part

Claims (6)

In the clamping device that can be adapted to be clamped to a plurality of workpieces having different clamping points by adjusting the position of the clamp supported by the clamp support tool,
The clamp support tool is provided with slider arms extending radially from the center of the tool, which is the center of the clamp support tool, as many as the number of clamp points, and sliders are provided on the slider arms so as to be adjustable and movable in the longitudinal direction. With
The tool center point is made to coincide with the clamp center point that is the intersection of a plurality of straight lines that pass through each clamp point of the workpiece and coincide with the opening angle of the adjacent slider arm, and each slider arm corresponds to To match or have a predetermined relationship with the straight line, and by moving each slider in the longitudinal direction of the corresponding slider arm, the clamp is positioned on the corresponding clamp point ,
The clamp point is a plurality of holes of three or more points, at least one of which is provided in advance on the workpiece so as not to be positioned on one concentric circle centered on the clamp center point,
A clamping device , wherein the workpiece is supported by inserting each clamp into each of the holes . The clamp includes a clamp portion that expands and contracts between a contracted state and a swelled state, and is inserted into the hole at the clamp point in a contracted state, and then is in a swelled state and is in close contact with the inner wall of the hole at the clamp point The clamping device according to claim 1, wherein The clamp part has a cylindrical shape made of an elastic member, and when the wire connected to the bottom part of the clamp part is pulled, the intermediate part of the clamp part swells radially outward, and when the wire is loosened, the clamp part is self-elastic. 3. The clamping device according to claim 2, wherein the restored and swollen portion contracts. 2. The clamp device according to claim 1, wherein the clamp has a hook shape for opening and closing the tip, and the tip is engaged with the workpiece by opening the tip when it comes out of the reference hole. 3. The clamp device according to claim 2, wherein the clamp portion is formed in a bag shape made of an elastic body, and is expanded or contracted by injecting or discharging a fluid into the clamp portion forming the bag shape. 2. The clamp device according to claim 1, wherein a hole for which a use other than the clamp has been determined in advance, such as fastening at the time of assembly, is used as the hole forming the clamp point.

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