CN112571137A

CN112571137A - Machine tool

Info

Publication number: CN112571137A
Application number: CN202010435161.9A
Authority: CN
Inventors: 田中博之; 山本悦生
Original assignee: Brother Industries Ltd
Current assignee: Brother Industries Ltd
Priority date: 2019-09-30
Filing date: 2020-05-21
Publication date: 2021-03-30
Anticipated expiration: 2040-05-21
Also published as: JP2021053767A; CN112571137B

Abstract

The present technology relates to a machine tool having a parallel link mechanism, which is capable of performing movement of an end effector. The machine tool comprises: a first support tray that supports a cutter; a plurality of first links, one end of which is connected to the first support tray in such a manner that the first links can rotate; a moving part to which the other end of the first link is rotatably connected and which is movable in a direction intersecting the first support tray; a second support disk which is opposed to the first support disk with a space therebetween in a direction in which the moving portion moves, and which supports the cutter; and a second link, one end of which is connected with the second support tray in a manner that the second link can rotate, and which is parallel to the first link.

Description

Machine tool

Technical Field

The present technology relates to a machine tool having a parallel link mechanism, which is capable of performing movement of an end effector.

Background

Japanese patent application laid-open No. 11-104987 discloses a parallel link mechanism. The parallel link mechanism has a plate having a triangular shape in a plan view and two arms (links) in parallel. One end of each arm is connected to each edge of the plate so that each arm can rotate. The moving member is rotatably connected to the other end of each plate. The cutter is held by the plate. The moving member moves in a direction crossing the plate, and the plate and the cutter move in a desired direction. When a cutting force in a direction parallel to the plate acts on the tool, the plate deforms, the position of the tool deviates from the target position, and chatter vibration during machining increases.

Disclosure of Invention

The invention aims to suppress deformation of a plate and improve machining accuracy and machining capability.

The machine tool according to claim 1 comprises: a first support plate which supports the end effector, and one end of the end effector penetrates through the first support plate; a plurality of first links, one end of which is connected to the first support tray in such a manner that the first links can rotate; a moving part to which the other end of the first link is rotatably connected and which is movable in a direction intersecting the first support tray; a second support plate which is opposed to the first support plate with a space therebetween in a direction in which the moving portion moves, and through which the other end portion of the end effector penetrates; a connecting part for connecting the first support disc and the second support disc; and a second link, one end of which is connected with the second support tray in a manner that the second link can rotate, and which is parallel to the first link.

The second supporting disk is arranged at a position separated from the first supporting disk, and the second connecting rod is arranged on the second supporting disk. Therefore, the rigidity of the machine tool is improved, the deformation of the link is suppressed, and the positioning accuracy of the end effector is improved.

In the machine tool according to claim 2, the distance between the first support tray and the second support tray is equal to or greater than the length of a portion of the end effector that protrudes downward from the first support tray.

The space between the first support disk and the second support disk is greater than the size of the protruding portion of the end effector. Therefore, the rigidity of the machine tool is further improved.

The other end of the second link of the machine tool according to claim 3 is connected to the moving part so that the second link can rotate.

The first link and the second link are coupled to the same moving part. Therefore, the manufacturing cost can be reduced as compared with a case where the first link and the second link are connected to different links.

In the machine tool according to claim 4, the second link has an urging portion that urges the second support plate.

The force application portion applies a preload to the second link. The stiffness is increased under the effect of the preload. The clearance between the parts becomes minimum and the vibration is absorbed, and therefore, the positioning accuracy of the end effector is improved.

Drawings

Fig. 1 is a schematic perspective view of a machine tool according to embodiment 1.

Fig. 2 is a schematic front view of the machine tool.

Fig. 3 is a schematic plan view of the machine tool.

FIG. 4 is a schematic sectional view taken along line IV-IV of FIG. 2.

Fig. 5 is a partially enlarged vertical cross-sectional view showing the first support plate, the second support plate, the connecting cylinder 8, and the vicinity thereof.

Fig. 6 is a schematic cross-sectional view of the machine tool with one moving part at a position lower than the other two moving parts.

Fig. 7 is a schematic plan view of the machine tool with one moving part at a position lower than the other two moving parts.

Fig. 8 is a schematic perspective view of the machine tool after the end effector has been modified.

Fig. 9 is a schematic perspective view of the machine tool after the end effector has been modified.

Fig. 10 is a schematic perspective view of a machine tool according to embodiment 2.

Fig. 11 is a schematic plan view of the machine tool.

Fig. 12 is a schematic perspective view of a machine tool according to embodiment 3.

Fig. 13 is a partially enlarged vertical cross-sectional view showing the first support tray, the second support tray, the end effector and the vicinity thereof according to embodiment 4.

Detailed Description

Embodiment mode 1

The present invention will be described below with reference to the drawings showing a machine tool according to embodiment 1. In the following description, the top, bottom, front, rear, left, and right in the drawings are used.

As shown in fig. 1 to 3, a machine tool 1 includes a base 2 having a rectangular shape in a plan view. A plurality of reinforcing cylinders 2a are provided on the upper surface of the base 2. The reinforcing cylinder 2a is parallel to the upper surface of the base 2. The holding base 3 is provided to a reinforcing cylinder 2a at the central portion of the upper surface of the base 2. The holding table 3 is cylindrical, and a workpiece is fixed to the upper surface of the holding table 3. Three columns 4 are provided around the holding table 3 and extend upward from the reinforcing cylinder 2 a. The three columns 4 are arranged at a phase interval of about 120 degrees apart in a plan view. The rail 5 is provided on a side surface of each of the columns 4 on the holding base 3 side, and extends in the vertical direction. The moving unit 6 is provided on the rail 5, and the driving source is provided on the rail 5. The driving source is a ball screw mechanism or the like. The moving section 6 moves in the up-down direction along the rail 5 by the driving of the driving source. That is, the moving portion 6 moves in a direction intersecting with a first support tray 10 described later. The later-described mounting portion is provided on the side surface of the moving portion 6 on the side of the holding base 3, and is a hole or a projection. The first support tray 10 is disposed above the holding base 3 and spaced apart from the holding base 3. The first support tray 10 has a triangular shape in plan view and is substantially parallel to the upper surface of the holding base 3. Three side portions of the first supporting plate 10 are opposed to the three pillars 4, respectively. That is, the three side portions correspond to the three moving portions 6, respectively. The side portions and the moving portions 6 are connected by two first links 11 in parallel. The first links 11 are rod-shaped, and one end portions of the two first links 11 are connected to both end portions of the side portion via rotatable joints 7 (see fig. 3). The other end portions of the two first links 11 are connected to the moving portion 6 via a joint 7 such as a rotatable universal joint. The end effector 30 protruding to the upper and lower sides is held by the first support tray 10. A cutter 30a is fitted to the lower end portion of the end effector 30.

As shown in fig. 5, the second support tray 20 is disposed above the first support tray 10 (on the side closer to the moving portion 6), and the connecting tube 8 (connecting portion) is provided between the first support tray 10 and the second support tray 20. The connecting cylinder 8 connects the first support disk 10 and the second support disk 20 in the vertical direction as the axial direction. The first support disk 10, the second support disk 20, and the connecting cylinder 8 are integrally formed. The upper portion of the end effector 30 is inserted into the connecting cylinder 8 and penetrates the second support plate 20. The vertical distance between the first support tray 10 and the second support tray 20 is, for example, equal to or longer than the length of a portion of the end effector 30 protruding downward from the first support tray 10 and shorter than the entire length of the end effector 30. The second support disk 20 has a triangular shape in plan view and is substantially parallel to the first support disk 10. The three side portions of the second support plate 20 are opposed to the three columns 4, respectively. That is, the three side portions correspond to the three moving portions 6, respectively. Each side portion and each moving portion 6 are connected by two second links 21. The second links 21 are rod-shaped, and one end portions of the two second links 21 are connected to both end portions of the side portion via joints 7 such as rotatable universal joints. The other end portions of the two second links 21 are connected to the moving portion 6 via rotatable joints 7. The connecting cylinder 8 has a hexagonal shape in plan view, and three side portions adjacent to each other in the circumferential direction, out of six side portions at the upper end portion thereof, are connected to three side portions of the second support tray 20. Three side portions adjacent to each other while skipping circumferentially among six side portions of the lower end portion of the connecting cylinder 8 are connected to three side portions of the first supporting plate 10. As shown in fig. 1 to 4, when the three moving portions 6 are at the same height position, the end effector 30 is located at a position substantially directly above the center of the holding base 3.

The cutting position (the position of the cutter 30 a) in fig. 6 is the same as the cutting position in fig. 4. As shown in fig. 6 and 7, when the two moving portions 6 are at the same vertical position and the other moving portion 6 moves to a position lower than the two moving portions 6, the end effector 30 moves in the horizontal direction to the side opposite to the side where the moving portion 6 moves downward. When the two moving portions 6 are at the same vertical position and the other moving portion 6 moves to a position above the two moving portions 6, the end effector 30 moves in the horizontal direction toward the moving portion 6 that has moved upward. When the three moving portions 6 move by the same distance in the up-down direction, the end effector 30 moves in the up-down direction. By combining these movement methods, the machine tool 1 can position the end effector 30 to a desired vertical position, front-rear position, and left-right position.

The end effector 30 is a spindle having a motor as a drive source. The spindle positioned at a desired position is rotated by driving of the motor, and the tool 30a attached to the spindle machines the workpiece held on the holding table 3.

As shown in fig. 2 and 4, the first link 11, the second link 21, the side surface portion of the connecting cylinder 8, and the moving portion 6 form a parallelogram shape when viewed from the horizontal direction (the front-rear direction or the left-right direction). When a force in the horizontal direction acts on the end effector 30 during workpiece processing, a moment acts on the end effector 30. At this time, there is a possibility that the first link 11 and the second link 21 are deformed. However, the above-described configuration forming the parallelogram shape has high rigidity, and the first link 11 and the second link 21 are not easily deformed.

In the machine tool 1 according to embodiment 1, the second support disk 20 is provided at a position apart from the first support disk 10, and the second link 21 is provided on the second support disk 20. Therefore, the rigidity of the machine tool 1 is improved, and the deformation of the first link 11 and the second link 21 can be suppressed, so that the positioning accuracy of the end effector 30 can be improved. Since the vertical distance between the first support tray 10 and the second support tray 20 is equal to or greater than the length of the portion of the end effector 30 that protrudes downward from the first support tray 10, the rigidity of the machine tool 1 is further improved. The first link 11 and the second link 21 are connected to the same moving part 6. Therefore, compared to the case where the first link 11 and the second link 21 are coupled to different moving parts, the manufacturing cost can be reduced. The second link 21 is parallel to the first link 11 in a top view and a side view.

The end effector 30 may be a member other than the spindle. The end effector 30 may be a claw capable of gripping an object as shown in fig. 8, or the end effector 30 may be a grindstone capable of grinding an object as shown in fig. 9.

Embodiment mode 2

The present invention will be described below with reference to the drawings showing a machine tool 1A according to embodiment 2. The same components as those in embodiment 1 in the configuration of embodiment 2 are denoted by the same reference numerals, and detailed description thereof is omitted. As shown in fig. 10 and 11, one end portions of the three second links 21 are connected to three side portions of the second support tray 20, respectively. One end of the second link 21 is connected to the center of the side. The other ends of the three second links 21 are connected to the three moving portions 6, respectively. That is, a single second link 21 is provided between the side portion and the moving portion 6. In embodiment 2, as in embodiment 1, the first link 11, the second link 21, the side surface portion of the connecting cylinder 8, and the moving portion 6 form a parallelogram shape when viewed in the horizontal direction, and the same operational effects as in embodiment 1 are exhibited.

Embodiment 3

The present invention will be described below with reference to the drawings showing a machine tool 1B according to embodiment 3. The same components as those in

embodiment

1 or 2 in the configuration of embodiment 3 are denoted by the same reference numerals, and detailed description thereof is omitted. As shown in fig. 12, each second link 21 has an urging portion 22, and the urging portion 22 urges the second support tray 20. The biasing portion 22 includes a spring, a hydraulic damper, a pneumatic damper, or the like, and the biasing portion 22 applies a preload to the second link 21. Therefore, the rigidity of the machine tool 1B is improved. Due to the action of the urging portion 22, the gap between the components is minimized and the vibration is absorbed, so that the positioning accuracy of the end effector is improved. The biasing portion 22 may be configured as follows. An adjusting mechanism for adjusting the position of the upper end of the second link 21 is provided in the moving section 6. The second link 21 is urged by the operation of the adjustment mechanism. The adjustment mechanism includes a cam mechanism or the like operable by rotation of a screw, and adjusts the position of the upper end of the second link 21 by the rotation of the screw, thereby applying a compressive force to the second link 21. As in embodiment 1, six second links 21 may be provided in the machine tool 1B, and each second link 21 may be provided with an urging portion 22.

Embodiment 4

The same components as those in embodiments 1 to 3 in the configuration of embodiment 4 are denoted by the same reference numerals, and detailed description thereof is omitted. As shown in fig. 13, embodiment 4 does not have the connecting cylinder 8. The middle section in the vertical direction of the end effector 30 protrudes outward in the horizontal direction. The horizontal direction corresponds to the left-right direction and the front-rear direction. The second support plate 20 is provided at the upper end of the protruding portion of the end effector 30, and the first support plate 10 is provided at the lower end of the protruding portion. That is, the end effector 30 constitutes a coupling portion for coupling the first support tray 10 and the second support tray 20.

Claims

1. A machine tool in which, in a machine tool,

the machine tool comprises:

a first support plate (10) which supports the end effector (30) and through which one end of the end effector penetrates;

a plurality of first links (11) one ends of which are rotatably connected to the first support plate;

a moving part (6) to which the other end of the first link is rotatably connected and which is movable in a direction intersecting the first support plate;

a second support plate (20) which is opposed to the first support plate with a space therebetween in a direction in which the moving section moves, and through which the other end of the end effector penetrates;

a connecting part (8) for connecting the first support disc and the second support disc; and

and a second link (21) having one end rotatably connected to the second support plate and parallel to the first link.

2. The machine tool of claim 1,

the distance between the first support tray and the second support tray is equal to or greater than the length of a portion of the end effector that protrudes downward from the first support tray.

3. The machine tool according to claim 1 or 2,

the other end of the second link is rotatably connected to the moving part.

4. The machine tool according to claim 1 or 2,

the second link has a biasing portion (22) that applies a force toward the second support tray.