JP7713691B2 - Parallel link type workpiece processing device - Google Patents

Description

Article 30, paragraph 2 of the Patent Act applied. April 21, 2022, in the meeting room at the headquarters of Thinks Co., Ltd. Distribution of a product summary created by the company that describes the technical details of the "Parallel Link Type Workpiece Processing Device"

Patent Law Article 30, Paragraph 2 applied Published on June 1, 2021, http://www.youtube.com/@SHINX1967/videos, SHINX1967 "Parallel link type workpiece processing machine"

Article 30, paragraph 2 of the Patent Act applies. June 30th to July 1st, 2022, Thinks Co., Ltd. Head Office 1st and 2nd Factory, "New Building Completion Commemorative Preview"

The present invention relates to a parallel link type workpiece processing device, which is preferably used, for example, as a woodworking router.

Woodworking routers that are widely used industrially are equipped with a fixed work table, for example, about 1m to 2m wide and 2m to 4m long, and a processing unit above it that can move in three directions, X, Y, and Z. The processing unit uses a drill-shaped cutting tool, which is the processing head, to apply decorative processing such as appropriate relief shapes to a workpiece fixed on the work table.

Such an apparatus has a table with the dimensions described above in order to accommodate the processing needs of large-sized workpieces, and not only does it require a large installation area, but it must also have a large range of movement for the processing unit.
However, on the other hand, there are many cases where the dimensions of the workpieces to be machined are limited to relatively small sizes, and a more compact device is also required.

As one method for responding to such a demand for compactness, a device using a so-called parallel link mechanism has been proposed (see, for example, Patent Documents 1 and 2).
However, this type of parallel link structure can be complicated in terms of, for example, accurately maintaining the posture of the processing unit that is responsible for direct processing, and accurately setting the shift movement, and so while it has been proposed as an idea, it is rarely offered on the market as an actual machine.

JP 2018-199194 A JP 2000-254876 A

The present invention was developed in consideration of this background, and the technical objective was to develop a parallel link type workpiece machining device that can achieve accurate machining control while keeping the linkage mechanisms for setting the machining units, which tend to be complicated, simple in configuration.

That is, the parallel link type workpiece machining device according to claim 1 is
A three-dimensional frame having both a frame extending in a vertical direction and a frame extending in a horizontal direction ;
A work table supported below the frame;
a processing unit that performs a predetermined processing on the workpiece on the work table;
a processing unit setting mechanism for supporting the processing unit in a suspended state from the upper portion of the frame,
A device for performing a predetermined processing on a workpiece on a worktable by moving the processing unit in a three-dimensional direction by a processing unit setting mechanism,
The processing unit setting mechanism includes a parallel setting mechanism and a shift setting mechanism,
The parallel setting mechanism includes:
an upper base plate attached to an upper portion of the frame, the upper base plate moving only in the vertical direction while maintaining a center position and a horizontal attitude;
A lower base plate is provided below the upper base plate and moves in three dimensions while taking a horizontal position.
a stabilizer column whose upper and lower ends are supported by a universal joint on the upper base plate and the lower base plate;
at least three parallel control rods disposed between an upper base plate and a lower base plate so as to surround the stabilizer column;
On the other hand, the shift setting mechanism has a plurality of shift cylinders arranged in parallel, and the working length of these shift cylinders is controlled to extend and retract. The upper ends of the shift cylinders are connected to the upper part of the frame and the lower ends of the shift cylinders are connected to the processing unit side. By controlling the working length of each shift cylinder to extend and retract, the processing unit is shifted in three dimensions while maintaining it in a horizontal position.

The parallel link type workpiece machining device according to claim 2 has, in addition to the requirements of claim 1,
The three-dimensional frame is
A gate frame and
A lower frame having a rectangular shape in a plan view connected to a lower portion of the gate frame; and an upper frame having a triangular shape in a plan view connected to an upper portion of the gate frame.
It is characterized by having four brace frames provided between the corner of the lower frame opposite the gate frame and the three corners of the upper frame.

The parallel link type workpiece machining device according to claim 3 has, in addition to the requirements of claim 1 or 2,
The lower base plate is arranged to support the lower part of the stabilizer column, and a unit support is arranged in a suspended state below the lower base plate, and the processing unit is characterized in that it is mounted on this unit support.

The parallel link type workpiece machining device according to claim 4 has, in addition to the requirements of claim 3,
The shift cylinder in the shift setting mechanism is composed of three cylinders, the upper ends of which are connected to three corner portions of the upper frame of the frame like universal joints, and the lower ends of the shift cylinders are connected to the unit support like universal joints.

The parallel link type workpiece machining device according to claim 5 has, in addition to the features of claim 1 or 2,
the parallel control rod in the parallel setting mechanism is provided between the upper base plate and the lower base plate and is connected to the upper base plate and the lower base plate by a ball joint;
The parallel control rod is characterized in that the upper base plate and the lower base plate are constantly biased in directions approaching each other by the rod holding mechanism.

The parallel link type workpiece machining device according to claim 6 has, in addition to the features of claim 1 or 2,
The shift cylinder in the shift setting mechanism is an electric cylinder having a ball screw mechanism,
The outer cylinder of the shift setting mechanism is provided with a torque stop mechanism between the outer cylinder and the frame,
The outer cylinder is also characterized by having a torque stop mechanism between the outer cylinder and the cylinder rod.

The parallel link type workpiece machining device according to claim 7 has, in addition to the requirements of claim 2 ,
The device is characterized in that it is provided with a tool stocker on the opposite side of the gate frame from the lower frame , which stores a plurality of tools to be attached to the machining head of the machining unit, allowing the appropriate tool to be selectively attached to the machining head.

The parallel link type workpiece machining device according to claim 8 has, in addition to the features of claim 1 or 2,
The upper base plate is connected to the upper frame by three flexible upper base plate support links arranged at equal angular intervals when viewed from a plane, and these upper base plate support links allow the upper base plate to move freely up and down relative to the upper frame while maintaining a horizontal state.
The above problems are solved by the configurations described in each claim.

First, according to the invention described in claim 1, a mechanism is provided in which multiple shift cylinders, which act as drive units, are arranged in parallel and act (extend and retract) simultaneously on the machining unit to control the position of the machining unit (a so-called parallel mechanism). In this way, the present invention controls the position of the machining unit from multiple directions, so compared to conventional mechanisms (so-called serial mechanisms) that moved the machining unit in three directions, X, Y and Z (three directions that are perpendicular to each other), the error per shift cylinder is averaged, and the machining unit can be controlled with high precision. In addition, the control for operating the machining unit can be made to have a simple structure, and the operating output per shift cylinder can be reduced. Furthermore, the device can be made more compact and lightweight, and space-saving installation can be achieved.

According to the invention described in claim 2, the three-dimensional frame is composed of a rectangular lower frame, a triangular upper frame, and four brace frames that connect the corners of these two frames from above and below, resulting in a polyhedral truss frame that ensures strong frame rigidity.

According to the invention described in claim 3, the mounting form of the processing unit is specified.

According to the invention described in claim 4, the number of shift cylinders and the connection form of both the upper and lower ends are specified.

According to the invention described in claim 5, both ends of the parallel control rod are connected to the upper and lower base plates by ball joints, and the ball joint connection is not released during processing. In other words, during processing, the processing unit moves to various positions, and the parallel control rod may also tilt (incline) significantly accordingly, but the present invention is provided with a rod holding mechanism, so the connection state of the upper and lower ball joints is always maintained.

According to the invention described in claim 6, the outer cylinder is provided with a torque stop mechanism between the frame and the cylinder rod, so that the extension and contraction of the shift cylinder can be controlled reliably and accurately.

According to the invention described in claim 7, since the machine is provided with a tool stocker that can store multiple tools, even if a tool needs to be changed during the machining of a single workpiece, such tool replacement work can be performed automatically by setting up a program in advance.

According to the invention described in claim 8, the support structure of the upper base plate is made concrete.

1 is a perspective view showing an example of a workpiece machining apparatus (parallel link type workpiece machining apparatus) of the present invention. FIG. FIG. 11 is a perspective view of the same as viewed from another direction. FIG. FIG. FIG. 1A is a side view showing the state around the tool stocker during workpiece machining (when the tool is stored), and FIG. 1B is a side view showing the state after switching to a tool exchange. 1A is a perspective view showing the state around the tool stocker during workpiece machining (when the tool is stored), and FIG. 1B is a perspective view showing the state after switching to a tool exchange. FIG. 4 is a perspective view showing a parallel setting mechanism. 1A is a perspective view showing the periphery of a rod holding mechanism in a parallel setting mechanism, and FIG. 1B is a perspective view showing FIG. 1A in a partially cutaway state. 13 is a side view showing how the rod holding mechanism maintains the holding state of the lower base plate even when the parallel control rod is tilted to almost its maximum extent. FIG. FIG. 4 is a perspective view showing a shift setting mechanism. FIG. 4 is a side view showing the periphery of the shift setting mechanism. 1A is a perspective view of the shift setting mechanism as viewed from another direction, FIG. 1B is a perspective view showing the shift setting mechanism in a partially cutaway state as shown in FIG. 1A, and FIG. 1C is a perspective view showing a torque stop mechanism between the outer cylinder and the cylinder rod. FIG. 13 is a perspective view showing the operation of the upper base plate support link. 1 is a perspective view showing a dust collection cover provided to surround a tool (machining head) during machining, and shows both a state during workpiece machining and a state during tool replacement. FIG. 1A is an explanatory diagram showing the movement range of the processing head in a side (front) view, and FIG. 1B is an explanatory diagram showing the movement range of the processing head in a plan view.

The present invention is as shown in the following examples, but these examples can be modified as appropriate within the scope of the technical concept of the present invention.

Hereinafter, a parallel link type workpiece machining device M (hereinafter simply referred to as workpiece machining device M) of the present invention will be specifically described based on the illustrated embodiment.
As shown in Figures 1 and 2 as an example, the workpiece processing device M comprises, as its basic components, a three-dimensional frame 1, a work table 2 arranged below the frame 1, a processing unit 3 that performs predetermined processing such as cutting on the workpiece W on the work table 2, and a processing unit setting mechanism 4 that supports the processing unit 3 in a suspended state from the upper part of the frame 1. The processing unit 3 is moved in three dimensions by the processing unit setting mechanism 4, and the workpiece processing device M performs the predetermined processing on the workpiece W on the work table 2.

Each of the above members will now be described.
First, the three-dimensional frame 1 will be described. As shown in Figures 1 to 5 as an example, the frame 1 comprises a gate frame 11 formed in a gate shape, a lower frame 12 extending rearward (horizontally) from the gate frame 11 below, and an upper frame 13 extending rearward from the gate frame 11 above. For convenience, in this specification, the side facing the gate frame 11 is referred to as the front or near side of the workpiece machining device M, and the opposite side, i.e., the side where the lower frame 12 and upper frame 13 are provided to extend (the opposite side of the gate frame 11), is referred to as the rear or far side.

1, 2 and 4, the lower frame 12 is formed in a rectangular frame shape in plan view, while the upper frame 13 is formed in a triangular frame shape in plan view. The triangular upper frame 13 includes an upper sub-frame 14 that connects the middle positions of the three sides of the upper frame 12.
A column-shaped brace frame 15 is provided diagonally between the lower frame 12 and the upper frame 13 , and essentially supports the upper frame 13 .

That is, the brace frame 15 is made up of four brace frames 15a, 15b, 15c, and 15d, with the lower end of brace frame 15a being connected to the rear corner of the lower frame 12, and the upper end being connected to the corner of the upper frame 13 closer to the gate frame 11, i.e., the front side. Similarly, the lower end of brace frame 15b is connected to the rear corner of the lower frame 12, and the upper end is connected to the rear apex corner of the upper frame 13.

The brace frame 15c has its lower end connected to the other corner of the lower frame 12, while its upper end is connected to the rear apex corner of the upper frame 13. Furthermore, the brace frame 15d has its lower end connected to approximately the same position as the brace frame 15c, while its upper end is connected to the corner of the upper frame 13 on the gate frame 11 side.
Thus, the frame 1 is configured by vertically connecting a triangular upper frame 13 and a rectangular lower frame 12 with a gate-shaped gate frame 11 (connected so that one side of the triangle and the rectangle overlap when viewed from above), and each vertex of the structure thus connected is further connected in the vertical direction by four brace frames 15. As a result, the frame 1 is formed as a truss frame with a polyhedral structure, and is configured to have strong rigidity. Incidentally, the entire frame 1 configured in this way presents a deformed pentagon (a so-called home plate shape) in plan view (see FIG. 4).

The lower frame 12 is not provided at the lowest end of the device (on the installation surface), but is provided at a position slightly raised above the installation surface by the leg frames 16. This leg frame 16 is substantially composed of a lower portion of the gate frame 11 and leg frames 16 provided at the two rear corners of the lower frame 12.
The frame 1 further includes a tool stocker frame 17 for storing several types of tools (cutting tools), which is provided on the rear outer edge of the lower frame 12 (see FIG. 2).

Such a frame 1 is provided with a work table 2 on the lower frame 12. A lateral platform 23 is attached to this work table 2 via linear bearings 22 so as to be able to move laterally on a lateral rail 21 provided on the lower frame 12, as shown in Fig. 5 as an example. Furthermore, a front-rear rail 24 is provided on this lateral platform 23 in the front-rear direction of the device, and a rectangular parallelepiped table main body 26 is provided on this front-rear rail 24 via linear bearings 25. As a result, the table main body 26 is configured to be able to move in the front-rear direction on the lateral platform 23.
Here, the reference symbol 23h in the figure denotes a gripping portion that is held by an operator when moving the lateral platform 23 laterally, that is, in the left-right direction.
In this embodiment, for example, two lateral pedestals 23 are provided, and two table bodies 26 that move in the front-rear direction on one lateral pedestal 23 (four in total) are provided, in order to accommodate various sizes of workpieces W. That is, when the workpiece W is large, the lateral pedestals 23 are widely separated, and the interval between the table bodies 26 on one lateral pedestal 23 is also secured to be wide. Conversely, when the workpiece W is small, it is not necessarily necessary to use all four table bodies 26.
The table body 26 is configured to be able to hold and fix the workpiece W by suction, for example, and suction holes for this purpose are formed in the workpiece holding surface. A suction path for this purpose is also formed in the traverse stand 23 on which the table body 26 is slidably placed.
The work table 2 is not necessarily limited to this type of configuration, and can take various forms, for example, a form in which the work W is clamped onto a flat mounting base.

Next, the processing unit 3 will be described.
The processing unit 3 is a unit that performs appropriate processing such as cutting on the workpiece W, and the processing unit 3 itself has a processing head 31, which is a cone-shaped tool T such as a router, and a drive unit 32 above it. The support form of the processing unit 3 will be explained in the processing unit setting mechanism 4. Incidentally, the processing unit 3 is not limited to cutting and relief processing on the workpiece W, but can also perform processing such as painting on the workpiece W by applying, for example, a paint nozzle as the processing head 31.
In this embodiment, since cutting is assumed as the actual machining performed on the workpiece W, as an example, as shown in Fig. 15, the machining head 31 is provided with a rectangular cylindrical dust collection cover 33 that surrounds the head. This dust collection cover 33 prevents chips generated during machining from scattering around and efficiently collects the chips. The chips generated during machining pass through a dust collection port 34 that opens from inside the dust collection cover 33 toward the upper front side of the machining head 31, and are collected through a flexible duct or the like that is appropriately connected to the dust collection port.
The dust-collecting cover 33 itself can be formed by attaching bristles in multiple rows or multiple layers to almost the entire circumference of the lower end of a plate-like member forming a rectangular tube. Furthermore, the dust-collecting cover 33 is configured so that the back side, i.e., the side facing the tool stocker 7, can be opened during tool replacement so as not to interfere with the tool replacement work. The reference symbol 33M in the figure denotes a drive motor for opening and closing the dust-collecting cover 33.

Next, the machining unit setting mechanism 4 will be described.
The machining unit setting mechanism 4 moves the machining unit 3 to an appropriate three-dimensional position, i.e., any position in the X, Y, and Z directions, while maintaining the horizontal attitude of the machining unit 3, and is composed of a parallel setting mechanism 5 and a shift setting mechanism 6. Of course, since the workpiece machining device M of the present invention employs parallel link machining, its movable range is subject to certain restrictions. Incidentally, the hatching in Figures 3 to 5 (so-called three-sided views) indicates the moving range of the machining head 31.

Hereinafter, the parallel setting mechanism 5 constituting the machining unit setting mechanism 4 will be described first.
The parallel setting mechanism 5 is responsible for maintaining the horizontal position of the machining unit 3, and is supported in a suspended state from the upper frame 13 of the frame 1. As shown in FIG. 8 as an example, the parallel setting mechanism 5 has an upper base plate 50 on the upper side, and the upper base plate 50 has a general shape called a deformed hexagonal shape when viewed from above, and is formed as a plate-like member with an opening at the center. The upper base plate 50 is attached to the upper subframe 14 so that the center position is secured by an upper base plate support link 51 and the upper base plate 50 can move in the vertical direction, as shown in FIG. 14 as an example. That is, the upper base plate support link 51 has a two-connection link structure in which a base link piece 51a is pin-connected to the upper subframe 14, and a plate side link piece 51b is similarly pin-connected to the other end side of the base link piece 51a, and the plate side link piece 51b is pin-connected to the upper base plate 50 at its free end side. The upper base plate support links 51 are provided at three locations, equally spaced apart (so-called three equal intervals) in a plan view.

As an example, as shown in FIG. 8, the upper part of the stabilizer column 52 is supported on the upper base plate 50. Specifically, the stabilizer column 52 is a pipe-shaped member with sufficient rigidity, and its upper end is supported on the upper base plate 50 in a universal joint manner by the upper universal joint 53a of the universal joint 53. More specifically, an elongated donut-shaped relay member 521 is provided between the upper base plate 50 and the stabilizer column 52 as the upper universal joint 53a. The relay member 521 is first connected to the outer upper base plate 50 so as to be rotatable in an appropriate direction (for example, left and right direction), and is further connected to the inner stabilizer column 52 so as to be rotatable in a direction different by 90 degrees (for example, front and rear direction) (see FIG. 9(b)). With this configuration, the stabilizer column 52 is configured to be able to move up and down by the upper universal joint 53a while freely moving downward in three-dimensional directions while securing the center position of the upper part.

Meanwhile, the lower end of the stabilizer column 52 supports the lower base plate 54. In the claims, the stabilizer column 52 is described as being provided between the upper base plate 50 and the lower base plate 54, but the lower base plate 54 itself is actually attached to the lower end of the stabilizer column 52. The lower end of the stabilizer column 52 and the lower base plate 54 are also connected in a universal joint manner by the lower universal joint 53b of the universal joint 53, as shown in Figures 8 and 9, as an example, in the same way as the upper part. That is, the reference numeral 522 in the figure denotes an elongated donut-shaped relay member provided between the lower base plate 54 and the stabilizer column 52, which actually constitutes the lower universal joint 53b.

Between the upper base plate 50 and the lower base plate 54, three parallel control rods 55 are provided, for example, at equal angular intervals so as to surround the stabilizer column 52. The upper and lower ends of these parallel control rods 55 are connected by ball joints between the upper base plate 50 and the lower base plate 54. The connection between the parallel control rods 55 and the upper base plate 50, and the connection between the parallel control rods 55 and the lower base plate 54 are maintained by a rod holding mechanism 56, which will be described below.

Here, in the present invention, the parallel link mechanism allows the machining unit 3 to be moved to an appropriate position, and in order to increase this degree of freedom, it is necessary to be able to greatly incline the parallel control rod 55. In other words, to obtain a wide range of movement for the machining unit 3, it is necessary to incline (tilt) the parallel control rod 55 at an angle larger than that of a normal ball joint connection (see FIG. 10).
For this purpose, it is desirable to obtain a wider range of motion than in a normal ball joint connection by making the engagement (fitting) between the ball portion and the ball catch portion that receives it smaller. However, simply adopting such a structure will inevitably result in the fitted ball portion easily coming out of the ball catch portion. In other words, in this embodiment, when the parallel control rod 55 is tilted to a certain extent, the ball joint portion will easily come out. For this reason, in this embodiment, a stopper is provided to prevent this, and this is the rod holding mechanism 56.

The rod holding mechanism 56 will be described in more detail below. First, the rod holding mechanism 56 that maintains the connection between the lower part of the parallel control rod 55, i.e., the parallel control rod 55 and the lower base plate 54, will be described with reference to FIG.
First, the stabilizer column 52 is divided into two parts, upper and lower, near the lower base plate 54, and flanges f1 and f2 are formed on each divided part, projecting outward from the outer periphery. A plate-shaped intermediate object is sandwiched between the flanges f1 and f2 (this is referred to as a clamped object 561), and the two are connected and fixed by bolts and nuts provided with a spring or other biasing body 562. With this configuration, the lower base plate 54 is biased upward, that is, against the ball portion of the lower end ball joint of the parallel control rod 55, preventing the ball joint from coming off.
As described above, the rod holding mechanism 56 is also provided on the upper part of the parallel control rod 55, i.e., between the parallel control rod 55 and the upper base plate 50, so that the parallel control rod 55 is prevented from coming out also at the upper and lower ball joint portions.
Due to this structure, in this embodiment, even if the parallel control rod 55 is tilted significantly, the ball joint portion will not come off (the connection of the ball joint portion will not be released).

Furthermore, below the lower base plate 54, as shown in FIG. 8 above as an example, a unit support 57 that supports the processing unit 3 is provided in a suspended state, and this unit support 57 is composed of a drive unit housing 57a and a head support 57b that is configured in a plate shape below it.

Next, the shift setting mechanism 6, which is another component of the machining unit setting mechanism 4, will be described.
The shift setting mechanism 6 performs a shift operation to move the machining unit 3 supported by the parallel setting mechanism 5 to an arbitrary position, and acts as a drive unit. As shown in Figures 4 and 11 as an example, the shift setting mechanism 6 is configured with three shift cylinders 61 such as electric cylinders, and the shift cylinders 61 include an outer cylinder 62 and a cylinder rod 63, and are configured to be freely extendable and retractable as a whole.
12, for example, the shift cylinder 61 rotates a drive ring 64R by a shift motor 64 provided below an outer cylinder 62. A cylinder rod 63 having a ball screw-like spiral shaft portion is screwed into the drive ring 64R, and the rotation of the drive ring 64R moves the cylinder rod 63 in the axial direction (i.e., the vertical direction), ultimately causing the cylinder rod 63 to extend and retract.
Of course, the cylinder rod 63 that screws into the drive ring 64R is configured so that it does not rotate even when the drive ring 64R rotates (so that the cylinder rod 63 moves up and down), and the configuration thereof will be described later.

The upper part of the outer cylinder 62 in the shift cylinder 61 is connected to the upper frame 13 via an upper joint 62J using a ball joint. Specifically, the outer cylinders 62 in the three shift cylinders 61 are connected near each vertex of the upper frame 13, which forms a triangular frame in a plan view (see FIG. 4). The lower joint 63J at the lower end of the cylinder rod 63 is also connected to three points around the head support 57b in the unit support 57 using a ball joint (see FIG. 5). Therefore, the three shift cylinders 61 are connected to the unit support 57 in the parallel setting mechanism 5 in a form that seems to converge downward from three points above. As will be described later, the processing head 31 is moved to an arbitrary position by setting the respective expansion and contraction states of the shift cylinders 61, and in this embodiment, the lower end of the cylinder rod 63 is connected to the head support 57b in consideration of the moment during the shift action. However, since the point is that it is sufficient to be able to position the machining head 31, it is of course acceptable to connect the lower joint 63J of the cylinder rod 63 to the lower base plate 54 of the parallel setting mechanism 5, for example.

Furthermore, in this configuration, the shift cylinder 61 is able to move freely up and down due to the ball joint connection, so even if the cylinder rod 63 is driven by the shift motor 64 in this state, the outer cylinder 62 may rotate as if it were spinning free under the driving torque, or the cylinder rod 63 may rotate, resulting in inaccurate extension and contraction. Therefore, the outer cylinder 62 and the cylinder rod 63 are each equipped with a torque stop mechanism.

First, as an example of the torque stop mechanism between the outer cylinder 62 and the frame 1, as shown in FIG. 11, a torque stopper protrusion 65 is provided on the upper part of the outer cylinder 62, while a protrusion receiver 66 is provided on the frame 1 side, thereby preventing the outer cylinder 62 from rotating.
13(c), a torque stop mechanism between the outer cylinder 62 and the cylinder rod 63 is configured such that a disk-shaped rotation stopper 67 is fixed to the upper end of the cylinder rod 63, and rectangular notches 671 are formed on the outer periphery of this rotation stopper 67 at two opposing locations on the diameter line. Also, two projections 68 that protrude inward are formed in the axial direction at two locations (two opposing locations on the diameter line) on the inner periphery of the outer cylinder 62, and the notches 671 on the cylinder rod 63 side and the projections 68 on the outer cylinder 62 side are engaged to stop the rotation of the cylinder rod 63 relative to the outer cylinder 62.

And with this configuration, even if the drive ring 64R driven by the shift motor 64 rotates, the entire shift cylinder 61 expands and contracts without the outer cylinder 62 and cylinder rod 63 rotating.

Here, the moving range of the processing head 31 (hatched in FIGS. 3 to 5) will be further explained with reference to FIG.
From the above mounting structure, one shift cylinder 61 moves while describing a conical (right circular cone) trajectory with the upper joint 62J as its apex and the shift cylinder 61 (the outer cylinder 62 and the cylinder rod 63) as its generating line.
As described above, the three shift cylinders 61 are disposed with a phase difference of 120 degrees in a plan view, and the machining head 31 is provided below the shift cylinders 61 via the head support 57b. Therefore, the machining head 31 is restricted by the three shift cylinders 61, and the planar path that the machining head 31 actually traces is like a cone traced by one shift cylinder 61 cut obliquely near the bottom, which results in an elliptical shape. In other words, the planar path that the machining head 31 actually traces is not a circular shape like the bottom of a cone, but an elliptical shape cut obliquely near this area.
Here, since there are three shift cylinders 61, three ellipses also overlap. That is, as shown in FIG. 16B as an example, the three ellipses overlap with their major axes shifted by 120 degrees (i.e., 60 degrees) each, similar to the planar arrangement of the shift cylinders 61, while their centers are aligned. Therefore, the inner area where the three ellipses overlap is the movement range of the machining head 31, which is a shape like a deformed hexagon. In this way, the planar movement range of the machining head 31 is a hexagon (deformed hexagon) as shown in the hatched areas in FIG. 4 and FIG. 16B.

Next, the movement range of the processing head 31 when viewed from the side or front will be described.
When one shift cylinder 61 is depicted in a vertical cross-sectional view of the machining head 31, the lower end of the machining head 31 is considered to describe a circle, as shown in Fig. 16(a) for example. On the other hand, the other shift cylinder 61 is disposed with a phase difference of 120 degrees in a plan view from the shift cylinder 61 that describes the circle, so the circular orbit described by the other shift cylinder 61 is seen at an angle, and becomes an elliptical orbit in a side view.
In side view (front view), the range surrounded by the circular orbit, the elliptical orbit, and the horizontal movement portion (below) of the machining head 31 is the movement range of the machining head 31. As shown in Fig. 16(a) above, this shape is a mountain shape with the central portion being higher at a slightly acute angle and the peripheral portions being lower. In this way, the movement range of the machining head 31 viewed from the side (front) is, for example, the shape shown in the hatched portions of Fig. 16(a), Fig. 3, and Fig. 5.

2, 6 and 7, the present embodiment further includes a tool stocker 7 for holding and storing various tools T used in actual machining such as cutting, and an appropriate tool T taken out from the tool stocker 7 is attached to the machining unit 3 to form the machining head 31. In the present embodiment, three tools T are stored in the tool stocker 7, but this number can be changed as appropriate.
The tool stocker 7 is supported by the tool stocker frame 17 of the frame 1, and the tool T is substantially held by a tool holder 71. Of course, this holding is intended to enable the tool T to be transferred between the tool holder 71 and the machining unit 3. Here, reference numeral 73 in the drawing denotes a tool holder cover that covers the tool T from above when stored, and is actually formed so as to entirely cover the upper part of the tool holder 71 that holds a plurality of tools T.
The tool holder 71 is configured to be able to move forward so as to supply the tool T to the machining unit 3 that has been shifted to be closest to the tool holder 71 during tool replacement. For this reason, the tool holder 71 is configured to be able to swing closer to the tool holder 71 by the shifter 72.

The following is a specific description of the swing approach operation of the tool holder 71. Note that, in the description, the operation will be described as the operation when the tool holder 71 is swung (rotated) forward from the tool storage state in which several tools T required for processing are stored to the tool exchange state.
From the time of storing the tool to the time of changing the tool, as shown in Figures 6 and 7, for example, the slider of the shifter 72 is first extended. This causes the tool holder 71 holding the tool T to rotate so as to protrude forward, i.e., to approach the actual machining part. In addition, with the extension of the slider of the shifter 72, the tool holder cover 73 that covered the stored tool T also rotates to open, and the upper part of the tool holder 71 protruding forward is exposed (see Figures 6(b) and 7(b)). This allows the machining head 31 to approach the tool stocker 7 and the tool change operation to be performed without any hindrance.
During tool replacement, the dust collection cover 33 surrounding the machining head 31 is opened as described above so as not to interfere with the tool replacement operation.

The workpiece machining device M of the present invention has the basic structure described above, and the machining mode of the workpiece W using this device will be described below.

(1) Setting (fixing) the workpiece
First, the table body 26 on which the workpiece W is placed is configured to be freely movable directly or indirectly on the lower frame 12, so the table body 26 is moved to an appropriate position. That is, the worker first operates the gripping portion 23h to appropriately move the lateral travel base 23 in the left-right direction, and then moves the table body 26 supported by the front-rear rails 24 on the lateral travel base 23 in the front-rear direction as appropriate.
In addition, to actually place the workpiece W on the table body 26, for example, the workpiece W is placed while two perpendicular sides of the workpiece W are placed against a reference pin or a screen-like guide plate, and it is common to set the workpiece W after determining the reference position for placement (which also serves as the reference position for processing).
After the workpiece W is set, the table body 26 may be moved to the rear side and the workpiece W may be placed on standby at an actual machining position where it is actually machined.

(2) Tool supply (installation)
In this manner, the workpiece W set on the table body 26 is machined by the machining unit 3. For machining, an appropriate tool T is taken out from the tool stocker 7 as described above and attached as the machining head 31. The machining head 31 essentially refers to a rotary blade or the like that is configured to be detachable from the drive unit 32. After the machining head 31 is set according to the purpose in this manner, appropriate machining such as cutting is performed according to an appropriate program.
6, for example, when the tool T is supplied, the slider of the shifter 72 extends, causing the tool holder 71 holding the tool T to move forward, i.e., closer to the machining unit 3, and the tool holder cover 73 covering the top of the tool holder 71 is also removed by the extension of the shifter 72, exposing the tool T. Of course, after the tool T is supplied, the slider of the shifter 72 contracts, and the tool holder 71 holding the tool T moves backward, i.e., toward the tool stocker frame 17, and the tool holder cover 73 also covers the top of the tool holder 71.
Incidentally, the tool T may of course be replaced during actual machining, and in that case, the same operation is performed to select the tool T suitable for the target machining.

(3) Processing (actual processing such as cutting)
During machining, the shift motor 64 in the shift setting mechanism 6 is driven by a preset machining program, and the working length of the three shift cylinders 61 is appropriately set. At this time, even if the three shift cylinders 61 move in an appropriate dimension, the lower base plate 54 maintains a horizontal position. In other words, since the upper base plate 50 is maintained in a horizontal position by the upper base plate support link 51 (parallel setting mechanism 5), the position of the lower base plate 54 itself moves in three dimensions, but it is set to a parallel state by the parallel control rod 55 (parallel setting mechanism 5) and the horizontal position is maintained.

As a result, the head support 57b of the unit support 57 provided below the lower base plate 54 remains horizontal, and the processing head 31 itself moves while maintaining its initial processing posture (for example, a vertical posture in the case of a drill bit). Of course, it is also possible to adopt a mechanism for deflecting and rotating the processing head 31 itself or the drive unit 32.
During actual machining, tool replacement may be performed as described above. In that case, the tool T is replaced and actual machining (cutting, etc.) is performed by the machining head 31 according to the procedure described above.
In this way, processing is performed sequentially by the processing head 31 according to the target program, and when this is completed, the processing unit setting mechanism 4, i.e., the parallel setting mechanism 5 and the shift setting mechanism 6, causes the processing unit 3 to move sufficiently upward away from the workpiece W, allowing the workpiece W to be removed.

In this embodiment, the above-mentioned rod holding mechanism 56 reliably holds the parallel control rod 55 (holds the lower base plate 54), so that the lower base plate 54 can continue to be held even if the parallel control rod 55 is tilted significantly. That is, the rod holding mechanism 56 acts to prevent the upper and lower ball joints of the parallel control rod 55 from coming off, so that the ball joints will not come off even if the rod holding mechanism 56 is tilted significantly (the connection of the ball joints will not be released).
After the processing of the workpiece W is completed, the work table 2 moves the table body 26 toward the gate frame 11 (front side) so that operations such as removing the workpiece W can be performed smoothly.

(4) Frame Shape In addition, in the parallel setting mechanism 5 and the shift setting mechanism 6, particularly in the frame 1, the lower frame 12 is formed in a rectangular frame shape when viewed from above, the upper frame 13 is formed in a triangular frame shape when viewed from above, and the front side is configured by a gate-shaped gate frame 11 having a rectangular opening on one side. Therefore, when arranging the three shift cylinders 61, it is easy to set the reference positions of the upper and lower three points, and the support of the upper base plate 50 in the parallel setting mechanism 5 can be rationally performed. In this respect, this frame configuration is extremely excellent.
It is also possible for the frame 1 itself to be formed as a rectangular frame in the shape of the entire frame 1, with the upper frame 13 and lower frame 12, which are located above and below, both formed as rectangular frames in a plan view; however, as mentioned above, by making the upper frame 13 a triangular frame in a plan view, the entire device is made lighter and more compact, while by configuring the lower frame 12 as a rectangular frame in a plan view, extremely high stability of the device itself is fully ensured.

M Workpiece machining device (Parallel link type workpiece machining device)
Reference Signs List 1 Frame 2 Work table 3 Machining unit 4 Machining unit setting mechanism 5 Parallel setting mechanism 6 Shift setting mechanism 7 Tool stocker

REFERENCE SIGNS LIST 11 Gate frame 12 Lower frame 13 Upper frame 14 Upper subframe 15 Brace frame 15a Brace frame 15b Brace frame 15c Brace frame 15d Brace frame 16 Leg frame 17 Tool stocker frame

21 traverse rail 22 linear bearing 23 traverse stand 23h gripping portion 24 front and rear rails 25 linear bearing 26 table body

31 Processing head 32 Drive unit 33 Dust collection cover 33M Drive motor 34 Dust collection port

50 Upper base plate 51 Upper base plate support link 51a Base link piece 51b Plate side link piece 52 Stabilizer column 53 Universal joint 53a Upper universal joint 53b Lower universal joint 54 Lower base plate 55 Parallel control rod 56 Rod holding mechanism 57 Unit support 57a Drive unit housing 57b Head support

61 Shift cylinder (electric cylinder)
62 outer cylinder 62J upper joint 63 cylinder rod 63J lower joint 64 shift motor 64R drive ring 65 torque stopper 66 stopper receiver 67 rotation stopper 68 projection

71 Tool holder 72 Shifter 73 Tool holder cover

521 Relay member (upper)
522 Relay member (lower)
561 Clamped body 562 Biasing body 671 Notch

f1 Flange f2 Flange T Tool (cutting tool)
Double Work

Claims (8)

A three-dimensional frame having both a frame extending in a vertical direction and a frame extending in a horizontal direction ;
A work table supported below the frame;
a processing unit that performs a predetermined processing on the workpiece on the work table;
a processing unit setting mechanism for supporting the processing unit in a suspended state from the upper portion of the frame,
A device for performing a predetermined processing on a workpiece on a worktable by moving the processing unit in a three-dimensional direction by a processing unit setting mechanism,
The processing unit setting mechanism includes a parallel setting mechanism and a shift setting mechanism,
The parallel setting mechanism includes:
an upper base plate attached to an upper portion of the frame, the upper base plate moving only in the vertical direction while maintaining a center position and a horizontal attitude;
A lower base plate is provided below the upper base plate and moves in three dimensions while taking a horizontal position.
a stabilizer column whose upper and lower ends are supported by a universal joint on the upper base plate and the lower base plate;
at least three parallel control rods disposed between an upper base plate and a lower base plate so as to surround the stabilizer column;
On the other hand, the shift setting mechanism has a plurality of shift cylinders arranged in parallel, and the working length of these shift cylinders is controlled to extend and retract. The upper ends of the shift cylinders are connected to the upper part of the frame and the lower ends of the shift cylinders are connected to the machining unit side. By controlling the working length of each shift cylinder to extend and retract, the parallel link type workpiece machining device is configured to shift the machining unit in three dimensions while maintaining it in a horizontal position.
The three-dimensional frame is
A gate frame and
A lower frame having a rectangular shape in a plan view and connected to a lower portion of the gate frame;
An upper frame having a triangular frame shape in a plan view connected to an upper portion of the gate frame;
2. The parallel link type workpiece machining device according to claim 1 , further comprising four brace frames provided between a corner portion of the lower frame opposite the gate frame and three corner portions of the upper frame.
3. The parallel link type workpiece machining device according to claim 1 or 2, characterized in that the lower base plate is arranged to support the lower part of the stabilizer column, and a unit support is arranged in a suspended state below the lower base plate, and the machining unit is mounted on this unit support.
4. The parallel link type workpiece machining device according to claim 3, characterized in that the shift cylinder in the shift setting mechanism is composed of three cylinders, the upper ends of which are connected to three corner portions of the upper frame of the frame in the form of universal joints, and the lower ends of the shift cylinders are connected to the unit support in the form of a universal joint.
the parallel control rod in the parallel setting mechanism is provided between the upper base plate and the lower base plate and is connected to the upper base plate and the lower base plate by a ball joint;
3. A parallel link type workpiece machining device according to claim 1, wherein the parallel control rod is configured to be biased by a rod holding mechanism in a direction in which the upper base plate and the lower base plate always approach each other.
The shift cylinder in the shift setting mechanism is an electric cylinder having a ball screw mechanism,
The outer cylinder of the shift setting mechanism is provided with a torque stop mechanism between the outer cylinder and the frame,
3. The parallel link type workpiece machining device according to claim 1, further comprising a torque stop mechanism between the outer cylinder and the cylinder rod.
3. The parallel link type workpiece machining device according to claim 2, further comprising a tool stocker on the opposite side of the gate frame from the lower frame for storing a plurality of tools to be attached to the machining head of the machining unit, so that an appropriate tool can be selectively attached to the machining head.
The parallel link type workpiece machining device according to claim 1 or 2, characterized in that the upper base plate is connected to the upper frame by three flexible upper base plate support links arranged at equal angular intervals when viewed from above, and the upper base plate is configured so that it can move up and down relative to the upper frame while maintaining a horizontal state by means of these upper base plate support links.