JPH09145342A - Cord guide device for linear guide apparatus - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a cord guide device which prevents dust particles from falling on a lower-part structure by a method wherein a cord guide is constituted of a flexible member installed along the movement direction of a moving member at the upper part of a guide and tension in the movement direction of the moving body is given to the flexible member. SOLUTION: End parts, on one side, of flexible members 10a, 10b are fixed to both ends of an X-carriage 4 at the upper part of an X-axis guide 2b, and a cord guide is formed. The members 10a, 10b are extended to the movement direction of the X-carriage 4 at the upper part of the X-axis guide 2b, they are bent downward and lowered along respective pulleys 11a, 11b, they are then raised via a U-shaped bend part, and their ends, on the other side, are fixed to parts near the rear surface of the X-axis guide 2b. Cylindrical weights 12a, 12b are placed at the inside of the U-shaped bend part. Thereby, the members 10a, 10b are stretched and installed without coming into contact with the surface of the X-axis guide 2b between the X-carriage 4 and the pulleys 11a, 11b. As a result, the members 10a, 10b are not rubbed with cables, and dust particles are not generated.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a cord guide device for a linear guide device.

[0002]

2. Description of the Related Art FIG. 3 is a perspective view of a movable bridge type three-dimensional measuring machine to which the prior art is applied. A Y-axis guide 3 is fixed on the surface plate 1, and a Y carriage 2 that moves along the Y-axis guide 3 in the Y-axis direction is guided. This is called the Y axis. The Y carriage 2 is a bridge structure, and has guide legs 2a having air pads of an air bearing (two sets of front and rear are arranged so as to face both side surfaces of the Y-axis guide 3 and an upper surface of the surface plate 1 (not shown)). It is composed of a support leg 2c having an air pad (not shown) at the lower end, and an X-axis guide 2b connecting the guide leg 2a and the support leg 2c above.

The X-carriage 4 is a structure which surrounds the X-axis guide 2b, has air pads (not shown) arranged so as to face each surface of the X-axis guide 2b, and
It is guided movably in the axial direction. This is called the X axis. The Z spindle 5 is guided by an air bearing formed between the Z spindle 5 and the X carriage 4 so as to be movable in the Z axis direction. This is called the Z axis. A measurement probe 6 is provided at the lower end of the Z spindle 5.

The X, Y and Z axes are the X carriage 4 and Y, respectively.
A drive device that drives the carriage 3 and the Z spindle 5 and a length measuring device that detects the amount of movement thereof are provided. Therefore, in the coordinate measuring machine, in the air bearing of each axis,
An air hose that supplies compressed air from an air source (not shown), and an electric cable (hereinafter, referred to as cables) that supplies electricity and signals to a drive device for each axis and a length measuring device are incorporated. The signal line and the power line of the probe 6 attached to the tip of the spindle 5 are also incorporated.

These cables are distributed from a control unit (not shown) to the Y carriage 2 for the Y axis, to the X carriage 4 otherwise, or to a predetermined position on the Z spindle 5 via the X carriage 4. It is set up. X,
There is flexibility between the fixed parts (respectively the X-axis guide 2b, the surface plate 1 and the X carriage 4) of the Y and Z axes and the movable parts (respectively the X carriage 4, the Y carriage 2 and the Z spindle 5). A cord guide is provided, and cables are arranged and connected along the cord guide.

The X axis will be described in detail below. The X carriage 4 is driven by the ball screw 7 and the motor 8 and moves along the X axis guide 2b. The amount of movement of the X carriage 4 is detected by a linear encoder (not shown) including a detection head attached to the X carriage 4 and a linear scale attached to the X-axis guide 2b.

A ball screw 7 is supported at both ends to support the X-axis guide 2
The brackets 13 and 14 attached to b are provided with a U-shaped rail 16 having an opening at the top in parallel with the X-axis guide 2b. The flexible cord guide 15 has one end fixed to one end portion 16a of the rail 16, crawls on the bottom portion of the U-shaped rail 16 and then stands up to form a U-shaped bent portion 15a to form an X-axis carriage. The other end portion is fixed to the holder 4a fixed to 4. Power and / or electric signals are supplied to the air hose that supplies compressed air to the X-axis and Z-axis air pads, and to the motors (8 for the X-axis) of the linear encoders and drive devices for the X-axis and Z-axis. An electric cable is arranged along the cord guide 15.

The portion of the cord guide 15 closer to the holder 4a than the U-shaped bent portion is kept in the air by the balance between the bending strength of the cord guide 15 and the weight of the cables. Then, as the X carriage 4 moves, the portion of the cord guide 15 forming the bent portion is displaced. At that time, the cord guide 15 and the rail 16 rub against each other. At the same time, the cord guide 15 and the cables also rub against each other. Such rubbing mainly occurs at the bent portion 15a. Then, as a result of the rubbing, dust was generated.

When the length of the cord guide 15 closer to the holder 4a than the U-shaped bent portion exceeds a certain value, the direction of the X-axis force acting on the X carriage 4 from the cord guide 15 is reversed, As a result, the driving load for moving the X carriage changes significantly, and the moving speed changes. FIG. 4A is a side view of the main part of FIG.
The state is shown in (b). Holder 4 rather than U-shaped bend
The action direction of the force when the length on the side a is short is shown in FIG.
On the contrary, the direction of action when it is long is indicated by an arrow in FIG.

Although not described, similar code guides are provided for the Y axis and the Z axis. However, there is nothing corresponding to the U-shaped rail 16 on the Z axis.

[0011]

In the conventional device having the above-mentioned structure, when the movable member moves, dust is generated and drops on the structure below the cord guide or on the object to be inspected, and There has been a problem of causing damage such as contaminating the test object. An object of the present invention is to provide a cord guide device in a linear guide device in which dust does not drop on a structure below or on a test object.

[0012]

In order to achieve the above object, the present invention provides a linear guide guide (2a) having a guide surface extending in a substantially horizontal plane, and a guide guide (2a). Movable member (4) and said movable member (4)
A cord guide device for a linear guide device having a cord guide for supplying at least one of electricity and compressed air to the cord and holding at least one of an electric cable and an air hose.
The flexible member (10a, 10b) is disposed above the movable member (4) so as to extend in the moving direction of the movable member (4), and the flexible member (10a, 10b) is provided with the movable member. Tension applying members (12a, 12b) for applying tension in the moving direction of (10a, 10b) are provided (claim 1).

In this case, the flexible members (10a, 10)
It is preferable that b) has a structure in which the end of the guide guide (2a) in the moving direction of the movable member (10a, 10b) is bent downward (claim 2).

[0014]

1 is a perspective view showing an embodiment of a coordinate measuring machine according to the present invention. The structure of the three-dimensional measuring machine measuring machine in the present embodiment is the same as that of the conventional apparatus except for the code guide described in detail below, and therefore, the same reference numerals as those in FIG. Hereinafter, the X-axis code guide will be described in detail.

Rotatable pulleys 11a and 11b are fixedly mounted on both ends of the X-axis guide 2b by support members 9a and 9b. On both sides of the X carriage 4, one end of the highly flexible member (for example, belt) 10a, 10b is X.
It is fixed to the X carriage 4 above the shaft guide 2b. The flexible members 10a and 10b extend in the moving direction of the X carriage 4 above the X-axis guide 2b, are bent downward along the pulleys 11a and 11b, respectively, and then descend and then rise through a U-shaped bent portion. The other end is fixed near the lower surface of the X-axis guide 2b. Cylindrical weights 12a and 12b are placed inside the U-shaped bent portion.

The flexible members 10a and 10b are cord guides. Cables are provided along the flexible members 10a and 10b.
It extends in the moving direction of the X carriage 4 above the shaft guide 2b, bends downward along the pulleys 11a and 11b, descends, and then rises via a U-shaped bent portion. The cables are connected from the end portions of the flexible members 10a and 10b on the X carriage 4 side to predetermined portions of the X axis and the Z axis (air pads, motors, linear encoders, etc.) through the inside of the X carriage 4 and the other end. From the section, for example, via a guide leg 2a and a support side leg 2c, it is connected to a controller and an air source (neither is shown).

When the X-carriage 4 moves along the X-axis guide 2b, one of the weights 12a and 12b placed on the flexible members 10a and 10b moves down, and the other moves up.
A constant tension is constantly applied to the flexible members 10a and 10b by the weight of the weights 12a and 12b. Thereby,
The flexible members 10a and 10b are stretched between the X carriage 4 and the pulleys 11a and 11b without contacting the upper surface of the X-axis guide 2b. Since this tension acts on both sides of the X carriage 4, they cancel each other out. Further, if the masses of the cables arranged on both sides of the X carriage 4 are distributed so as to be substantially equal, the forces received by the X carriage 4 from the cables cancel each other out. As a result, even if the X carriage 4 is moved, the force acting on the X carriage 4 is almost constant, and the change in the moving speed can be reduced.

Further, since the flexible members 10a and 10b and the cables are not rubbed above the X-axis guide 2b (also above the object to be inspected), dust is not generated. Even if it should occur, the X-axis guide 2b extends downward so that it does not fall directly onto the test object. As the flexible member in the above-described embodiment, in addition to the belt, a flexible tube or a large number of short tubular members 17 (including partially cutout members) are rotatably connected to each other by a connecting shaft 18. It may be an articulated tube (see FIG. 2) or the like. Further, as another means for applying tension to the flexible member, the pulley 11a,
The pulley 11a, 11b may be preliminarily provided with a rotating force in a direction in which tension is applied to a portion of the flexible member 10a, 10b on the X-axis guide, by a spring spring incorporated in the pulley 11b. In this case, a sufficiently large frictional force acts between the pulleys 11a and 11b and the flexible members 10a and 10b,
The rotational force in the opposite direction to the rotational force given in advance is applied to the flexible member 10.
When the springs a, 10b act on the pulleys 11a, 11b, the strength of the spring is selected so that the spring is wound. In order to ensure this, it is also conceivable that the pulleys 11a and 11b have teeth and the flexible member is provided with a corresponding hole.

If the width of the flexible members 10a, 10b is set to be the same as or close to the width of the X-axis guide 2b, the upper surface of the X-axis guide 2b is covered, and thus a dustproof device against dust coming from the outside. Can also serve as

[0020]

According to the cord guide device of the present invention, there is no rubbing portion which causes dust in the moving range of the movable member, and the guide guide is located below even if dust is generated. Dust does not fall on the structure below or on the test object.
Further, in the invention of claim 2, since the cord guide (flexible member) is bent downward at both ends of the guide guide in the moving direction of the moving member, the structure is compact.

[Brief description of the drawings]

FIG. 1 is a perspective view showing an embodiment of a coordinate measuring machine of the present invention.

FIG. 2 is a perspective view of an example of a flexible member.

FIG. 3 is an explanatory diagram of a code guide of a coordinate measuring machine according to the related art.

4 is an explanatory view of the influence of the code guide in the apparatus of FIG.

[Explanation of reference symbols] 1 ... Surface plate 2 ... Y carriage 2b ... X axis guide 3 ... Y axis guide 4 ... X carriage 5 ... Z spindle 6 ... Detection probe 7 ... Motor 8 ... Ball Screws 10a, 10b ... Flexible members (code guides) 11a, 11b ... Pulleys 12a, 12b ..

Claims (2)

[Claims] 1. A linear guide having a guide surface extending in a substantially horizontal plane, a movable member that moves along the guide, and an electricity supplying at least one of electricity and compressed air to the movable member. In a cord guide device of a linear guide device having a cord guide for holding at least one of a cable and an air hose, the cord guide is arranged above the guide guide so as to extend in the moving direction of the moving member. A cord guide device for a linear guide device, comprising a flexible member, which is provided with a tension applying member for applying a tension in the moving direction of the moving member. 2. The cord of the linear guide device according to claim 1, wherein the flexible member is bent downward at an end portion of the linear guide member in a moving direction of the moving member. Guide device.