JPH0541365B2 - - Google Patents

Description

[Detailed Description of the Invention] <Industrial Application Field> The present invention relates to a preload type for robots used for drilling, reaming, tapping, etc. of a workpiece having a three-dimensional curved surface, such as an airplane engine cover. Regarding tool holders.

<Prior Art> Conventionally, there are the following two methods for drilling a workpiece having a three-dimensional curved surface. The first method takes advantage of the robot's wide working area, versatility, and adaptability by clamping a drilling device to the end of the robot's arm, and also attaches a fourth drill to the workpiece.
A highly accurate template 1 as shown in the figure is set, and a drill (not shown) is guided through a guide hole 22 of the template to compensate for runout of the drill and poor positioning accuracy due to the low rigidity of the robot.

The second method uses a highly rigid five-axis machine tool that can control the position and orientation of the drill.

<Problems to be Solved by the Invention> However, in the first method using the conventional template 1, as is well known, the template 1 itself is expensive and bulky, and in addition, it is difficult to attach/remove the template 1. There is a problem that it takes time to change the setup.

Furthermore, the second method has problems in that the five-axis machine tool is expensive, large, heavy, and has a narrow operating range.

Therefore, this invention was made to solve the above problem, and its purpose is to improve the workability, versatility, and adaptability of robots over a wide range of areas when drilling holes in workpieces having three-dimensional curved surfaces. It is an object of the present invention to provide a preload type tool holder for a robot that can compensate/improve the weak points of the robot, such as low rigidity and low accuracy, without using a template, while making the most of the

<Means for Solving the Problems> In order to solve the above problems, the preloaded tool holder for robots of the present invention has a tool holder for robots that slides in the direction of the work on the arm 26 of the robot 5, as illustrated in FIG. a tool support member 11 that can be attached to the tool support member 11 and supports a tool device; a cone-shaped support member 12 having a hole through which a tool of the tool device passes; and a cone-shaped support member 12 interposed between the cone-shaped support member 12 and the arm 26 of the robot 5 to push the arm 26 in the direction of the workpiece. The tool support member 11 is provided with an elastic member 32 that applies a preload to the cone-shaped support member 12 due to elastic deformation caused by pressure, and the tool support member 11 is in contact with the workpiece via the cone-shaped support member 12. It is characterized by supporting tool equipment.

In addition, in the preload type tool holder for a robot, a semicircular part 21 having a shape of a cylinder cut out along the generatrix line is coaxially formed at the tip of the cone-shaped support member 12. It is desirable to install an outwardly directed air pipe 25.

<Operation> When the elastic member 32 is pressed in the direction of the work by the arm 26 of the robot 5 in the non-operating state of the tool device, the preload generated by the elastic deformation of the elastic member 32 is applied to the cone-shaped support member. 1
2, this cone-shaped support member 12 is pressed against the workpiece, and its tip comes into contact with the workpiece.

In this way, the cone-shaped support member 12 is attached to the workpiece.
When the tool device is operated with the tips of the cone-shaped support member 11 in contact and fixed, dynamic loads such as machining reaction force and vibration acting on the tool supported by the tool support member 11 are applied to the cone-shaped support member 11. 12 and the arm 26 via the elastic member 32, and the dynamic loads such as the processing reaction force and vibration are shared between the cone-shaped support member 12 and the arm 26. Therefore, the dynamic load, etc. borne by the arm 26 is reduced.

Further, at this time, the tool device is supported by a tool support member 11 that is fixed in contact with the workpiece via the cone-shaped support member 12. The workpiece, the tool arrangement, the tool support member 11, the cone-shaped support member 12 and the workpiece are thus connected to each other to form a closed system. In this way, the tool support member 11 that supports the tool device
is fixed to the robot 5 via the arm 26, further fixed to the workpiece via the cone-shaped support member 12, and fixed to the two bases.
As a result, the rigidity of the robot appears to have improved. Therefore, the weak points of the robot, such as low rigidity and low precision, are compensated for/improved and the workpiece is machined without using a template.

Further, the cone-shaped support member 12 has a substantially conical shape that tapers toward the tip that contacts the workpiece, thereby reducing the contact area of the tip with the workpiece and allowing the tool to pass through the hole in the tip. Because there are
The tip portion is brought into close contact with the vicinity of the machining portion of a workpiece having a three-dimensional curved surface, so that machining of the workpiece having a three-dimensional curved surface can be easily and accurately performed.

Furthermore, in the preload type tool holder for a robot, the semicircular shape is moved by air blown from the air pipe 25 attached to the semicircular part 12 coaxially formed at the tip of the cone-shaped support member 12. Chips are blown away from the notch in the shaped portion 12. In this way, a workpiece having a three-dimensional curved surface can be processed with good work efficiency.

<Examples> The present invention will be described in detail below with reference to illustrated examples.

In Fig. 1, 5 is a multi-jointed robot, 6
7 is a preload type tool holder provided at the tip of the arm of the robot 5, 7 is a drill unit with an auto feeder as an example of a tool device fixed to the tool holder 6, and 8 is a workpiece having a three-dimensional curved surface fixed on a pedestal 9. .

The tool holder 6, as shown in FIG.
A cylindrical drill unit support member 11 and a hollow cone-shaped support member 12 are coaxially fixed with bolts (not shown). The above drill unit support member 1
1, a drill unit 7 is coaxially fixed therein.

The cone-shaped support member 12 has a conical shape that tapers toward the tip 15. The tip portion 15
A jig bush 18 for guiding the drill 17 of the drill unit 7 is press-fitted into a through hole 16 provided at the axis of the drill unit 7 and fixed therein. The jig bush 18 is positioned with its flange portion 18a abutting against the inner plane of the tip portion 15.

As shown in FIGS. 2 and 3, the tip portion 15 has a semicircular portion 21 formed by cutting out approximately half of a cylinder coaxial with the axis of the tip portion 15 and protruding downward. . Both ends 21 of the semicircular portion 21
a, 21a are located on both sides of the drill 17 in the diametrical direction. A semicircular rubber plate 22 is attached to the tip end surface of the semicircular part 21, and this semicircular rubber plate 22 is used as a contact surface with the workpiece 8 (see FIG. 1) to prevent damage to the workpiece 8 Workpiece 8 of shaped support member 12
Prevents slipping. The above semicircular part 2
A metal fitting 25a of an air pipe 25 is connected to the center of one side of the drill bit 1, and air is blown from the air pipe 25 to blow away chips generated by the drill 17.

On the other hand, as shown in FIG. 2, a ring portion 26a at the tip of the arm 26 of the robot 5 is fitted onto the outer periphery of the drill unit support member 11 so as to be slidable in the axial direction of the drill 17, and a fixing nut 35 is fitted onto the outer periphery of the drill unit support member 11. , 36. A plate spring 32, which is an example of the elastic member, is mounted between the arm 26 and the flange portion 31 at the lower end of the drill unit support member 11. Therefore, the arm 26 slides on the outer peripheral surface of the drill unit support member 11, and the plate spring 3
2, the cone-shaped support member 12 can be pressed in the axial direction, that is, in the preload direction.

The rubber plate 22 of the tip 15 of the cone-shaped support member 12 of the preloaded tool holder 6 for a robot having the above structure is brought into contact with the vicinity of a desired part of the workpiece 8 having a three-dimensional curved surface shown in FIG. hand,
The tip of the drill 17 is made to face the part to be machined. Then, the ring portion 26a of the arm 26 of the robot 5 presses the cone-shaped support member 12 in the axial direction via the plate spring 32 to apply a preload to the cone-shaped support member 12 and the plate spring 32, and the cone-shaped support member 12 and the plate spring 32 are preloaded. The cone-shaped support member 12 is fixed by bringing the rubber plate 22 of the semicircular portion 21 formed at the tip of the support member 12 into contact with the workpiece 8 .

By doing so, the work 8, the drill unit support member 11, the cone-shaped support member 12, and the work 8 are connected to each other to form a closed system. In this way, the drill unit support member 11 that supports the drill unit 7 is fixed to the robot 5 via the arm 26, and is also fixed to the workpiece 8 via the cone-shaped support member 12.
It will be fixed to one base. As a result, the apparent rigidity of the arm 26 of the robot 5 is increased, and the drill unit 7 is reliably positioned and supported.

Next, the drill unit 7 is driven, the drill 17 is lowered through the jig bush 18, and the workpiece 8 is drilled.

At this time, the drill unit 7 is supported not only by the arm 26 of the robot 5, but also by the workpiece 8, the drill unit 7, the drill unit support member 11, the cone-shaped support member 12, and the workpiece 8, which are connected to each other. The drill unit support member 1 forms a closed system and is fixed to two bases of the workpiece 8 and the robot 5 via the cone-shaped support member 12 and the arm 26.
1, it is possible to compensate for the low rigidity of the arm 26, etc. of the robot 5, and to ensure high positioning accuracy. In addition, dynamic loads such as vibrations applied to the drill 17 of the drill unit 7 are transmitted to the arm 26 of the robot 5 via the cone-shaped support member 12 and the leaf spring 32, so the dynamic load that the arm 26 of the robot 5 takes on is reduced. Reduced.

Further, since the rubber plate 22 at the tip 15 of the tapered cone-shaped support member 12 serves as a contact surface with the workpiece 8, the contact area is small, and therefore the workpiece 8 has a three-dimensional curved surface. Even if the drill unit is supported by the cone-shaped support member 12 or the like, machining can be performed. Furthermore, since the rubber plate 22 at the tip of the cone-shaped support member 12 comes into contact with the workpiece 8 near the hole-drilling location, operability in moving/positioning the tool holder 6 is good, and bending moment is not applied to the tool holder 6. Nor. The rubber plate 22 prevents damage to the workpiece 8 and prevents the cone-shaped support member 12 from slipping.

During the above-mentioned drilling process, the jig bush 18 provided at the tip 15 of the cone-shaped support member 12 guides the drill 17, so that the tip of the drill 17, which is the tip when machining a curved surface, is prevented from wobbling. Dancing can be prevented.

During and after such drilling,
Air is blown out from the center of the semicircular part 21 through the air pipe 25 to blow off the chips in one direction. At this time, air is guided by the curved surface of the semicircular portion 2, and the chips are reliably blown away in one direction. Also, the semicircular portion 21 allows the workpiece 8 to
A space is created between the tip portion 15 and the tip portion 15, making it easier to discharge chips from the machined hole.

In the above embodiment, the drill unit support member 11
The outer circumferential surface of the plate spring 32 is used as a guide in the preload direction, and the ring portion 26a of the arm 26 is slid on it to preload the leaf spring 32, so the structure is simple, there is little backlash (gap), and a stable preload is evenly distributed. Can be hung. Furthermore, since the leaf spring 32 is used as the elastic member, it is possible to achieve compactness. Further, since the tool holder 6 is attached to the arm 26 of the robot by nuts 35 and 36, it can be easily replaced, and the tool holder can be replaced depending on the shape of the tool device and the workpiece.

In the above embodiment, the drill unit support member 11
Although the cone-shaped support member 12 and the cone-shaped support member 12 are constructed as separate structures, they may be constructed as an integral structure. Further, the cone-shaped support member may be one in which a plurality of rods are arranged on a conical surface. Further, the elastic member is not limited to a plate spring, but may be a coil spring or an elastic member made of synthetic resin such as rubber. The jig bushings may be removed. Further, as the tool device, a reamer device, a tap device, or the like may be used.

<Effects of the Invention> As is clear from the above, the preloaded tool holder for a robot of the present invention has a hole through which the tool passes through one end of the tool support member attached to the arm so as to be slidable in the direction of the workpiece. At the same time, a cone-shaped supporting member having a substantially conical shape tapering toward the tip that contacts the workpiece is formed, and a cone-shaped support member is formed between the cone-shaped supporting member and the arm, and is elastically deformed by pressing the arm in the direction of the workpiece. The tool device is supported by the tool support member that is in contact with the workpiece via the cone support member, by interposing an elastic member that applies the resulting preload to the cone support member. Therefore, the tip of the cone-shaped support member is brought into contact with the work by the preload generated by pressing the arm in the direction of the work, and the arm and elastic member, one end of which is fixed to the base (robot), are The tool support member can be supported by the composite body and a cone-shaped support member whose one end is fixed to the base (workpiece).

Therefore, according to the present invention, while making maximum use of the robot's workability, versatility, and adaptability over a wide range of areas, it is possible to compensate for the weak points of the robot, such as low rigidity and low accuracy, without using a template.
This makes it possible to drill holes in workpieces with three-dimensional curved surfaces.

Further, in the preload type tool holder for a robot of the present invention, a semicircular part having a shape of a cylinder cut out along the generatrix line is formed coaxially at the tip of the cone-shaped support member. If an air pipe directed outward is attached, chips generated during machining of a workpiece with the above-mentioned tool can be easily discharged to the outside.

[Brief explanation of the drawing]

FIG. 1 is an overall perspective view of an embodiment of the present invention, FIG. 2 is a longitudinal sectional view of the embodiment, FIG. 3 is a bottom view of the embodiment, and FIG. 4 is a perspective view of a template. 5... Robot, 6... Preload type tool holder, 7... Drill unit, 12... Cone-shaped support member, 16... Through hole, 26... Arm, 3
2...Plate spring.

Claims (1)

[Scope of Claims] 1. A tool support member 11 that is attached to the arm 26 of the robot 5 so as to be slidable in the direction of the workpiece and that supports a tool device; A cone-shaped support member 1 having a substantially conical shape that tapers toward the tip that contacts the cone, and has a hole in the tip that allows the tool of the tool device to pass through.
2, the arm 26 is interposed between the cone-shaped support member 12 and the arm 26 of the robot 5;
The cone-shaped support member 1
2. A preloaded tool for a robot, characterized in that the tool device is supported by the tool support member 11 which is in contact with the workpiece via the cone-shaped support member 12. holder. 2. In the preloaded tool holder for a robot according to claim 1, a semicircular portion 21 having a shape of a cylinder cut out along the generatrix line is formed coaxially at the tip of the cone-shaped support member 12. and an air pipe 2 directed outward to the semicircular portion 12.
A preload type tool holder for robots, which is characterized by the fact that 5 is attached.