JP2003326429A - Machine tool having hybrid guide mechanism - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To systematically improve motion accuracy and damping property in unification as a whole, and inversely, increase the damping property or the like in a well-balanced manner in response to individual conditions. <P>SOLUTION: In regard to all linear axes, the X-axis, Y-axis and Z-axis, a roll guide and a slide guide or a hybrid guide combining the roll guide with the slide guide are used in a guide mechanism for a table 12, a saddle 8 and a cross rail 6. <P>COPYRIGHT: (C)2004,JPO

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a guide device for guiding a linear motion of a table of a machine tool or the like, and more particularly, as a guide mechanism, a rolling guide and a sliding guide, or a hybrid guide combining a rolling guide and a static pressure guide. The present invention relates to a machine tool having a mechanism.

[0002]

2. Description of the Related Art In machine tools, columns, spindle heads,
The guide mechanism for moving objects such as tables is
They are mainly sliding guides and rolling guides.

The sliding guide has a sliding contact type with a guide surface, has a high static rigidity, and is superior to a rolling guide in damping properties against vibrations that cause chattering.

On the other hand, the rolling guide has a rolling contact with the guide surface and has a low damping property against vibration, but has a small frictional resistance and is superior to the sliding guide in terms of high speed and motion accuracy. In short, the sliding guide and the rolling guide have the advantage that each other has the advantage, and the advantage that the other has the disadvantage.

Conventionally, the slide guide has been mainly used as the guide mechanism for the moving body of the machine tool.
With the strong demand for higher speeds of machines, rolling guides are often adopted.

A hybrid type guide mechanism combining a slide guide and a rolling guide is becoming widespread. In the case of heavy-cutting low-speed feed requiring damping, the slide guide is mainly used, and in the case of high-speed feed. It is possible to make the most of the advantages of both, such as rolling guidance. As a conventional technique of such a hybrid guide device,
For example, JP-A-9-131634 and 2001-9
The thing disclosed in 655 can be mentioned.

[0007] Such a tendency is shown in JP-A-9-13163.
The same is true of conventional hybrid type guide devices such as the guide device of No. 4, and while ensuring the damping property mainly by the slide guide, the uplift which is the defect of the slide guide is suppressed and high speed adaptability is added. Therefore, the basic design concept is to use rolling guidance as a complement to sliding guidance.

[0008]

The motion accuracy and damping of the guide for each axis have a considerable influence on the quality of the machined surface of the workpiece. It is also known that these characteristics also affect tool life.

In general, the motion accuracy and the damping property are not simple, and it goes without saying that the motion accuracy and the damping property as a whole for all axes are a problem. In some cases, the damping property may become a problem during high-speed operation.

Especially, when a workpiece is machined to a complicated shape having a free-form surface with high precision by simultaneous control of three or more axes, the overall motion accuracy and damping are systematically integrated in a well-balanced manner. However, the present situation is that there is no effective solution.

Therefore, an object of the present invention is to solve the above-mentioned problems of the prior art and systematically improve the motion accuracy and damping property as a whole, and vice versa. Another object of the present invention is to provide a machine tool having a hybrid guide mechanism capable of increasing damping properties and the like.

[0012]

In order to achieve the above-mentioned object, the present invention provides a machine tool having a plurality of linear axes that respectively give a linear motion to a table, a saddle, a spindle head, and other moving bodies. With respect to the linear axis, the guide mechanism of the moving body uses rolling guide and sliding guide, or hybrid guide combining rolling guide and static pressure guide.

It is preferable that the hybrid guide is a combination of a rolling guide which constitutes a main guide serving as a linear motion reference on the base of the moving body and a sliding guide which serves as a secondary guide which complements the rolling guide. .

[0014]

BEST MODE FOR CARRYING OUT THE INVENTION An embodiment of a machine tool having a hybrid guide mechanism according to the present invention will be described below with reference to the accompanying drawings.

FIG. 1 is a view showing the outer shape of a portal machining center to which the present invention is applied. In FIG. 1, reference numeral 2 indicates a column and 4 indicates a bed.

A cross rail 6 (covered with a bellows cover in FIG. 1) is installed on the column 2 so as to be vertically movable. A saddle 8 is installed on the cross rail 6 so as to be horizontally movable left and right, and a spindle head 10 is attached to the saddle 8. On the bed 4 (covered with a bellows cover in FIG. 1), the table 12 moves in the front-rear direction. In FIG. 1, the X-axis is a shaft for feeding the table 12 in the front-back direction, the Y-axis is a shaft for feeding the saddle 6 in the left-right direction, and the Z-axis is a shaft for feeding the cross rail 6 in the vertical direction. In the portal machining center of FIG. 1, these X-axis, Y-axis, and Z-axis are all linear axes.

In the present embodiment, the hybrid guide combining the rolling guide and the sliding guide is the X axis, Y axis, and Z axis.
It is used as a shaft guide mechanism. Hereinafter, these hybrid guides will be sequentially described.

1. X-axis guide FIG. 2 shows a hybrid guide for guiding the table 12 on the bed 4, and is a view of the table 12 viewed from the front in the moving direction.

On the upper surface of the bed 4, a pair of guide rails 14a and 14b are laid on the left and right sides in parallel with the ball screw 13. Rolling guide units 15a and 15b are attached to the lower surface of the table 12, and are engaged with the guide rails 14a and 14b, respectively. In this case, the weight of the table 12 is reduced by the guide rails 14a, 14 via the rolling guide units 15a, 15b.
It is designed to cover b. Rolling guide unit 15
Each of a and 15b has a roller (not shown) built therein, and the roller rolls on the guide rails 14a and 14b.

In this X-axis guide, a rolling guide is mainly used to form a guide surface that serves as a reference for the linear movement of the table 12 on the bed 4. This guide surface is parallel to the bed top surface.

In order to complement the above-mentioned rolling guide, the following sliding guides as sub guides are arranged and combined outside the rolling guide to form a hybrid guide.

Sliding surfaces 16a, 16a are respectively provided on the side surfaces of the bed 4 on both the left and right sides of the table 12 in the feeding direction.
16b are formed, and these sliding surfaces 16a, 1
6b extends parallel to the guide rails 14a and 14b. In relation to the main guide surface composed of rolling guides, the sliding surface 1
6a and 16b are vertical.

Reference numerals 18a and 18b denote slip guide units, respectively. Sliding guide unit 18a, 1
8b is a main body portion 19a, 19b and a slip surface 16a, 1
The slider 6a is composed of sliders 20a and 20b which slide on the slider 6b. In this embodiment, the body portions 19a, 1
9b is a block body having an L-shaped cross section, and sliders 20a and 20b are fixed to the lower end portion bent at a right angle.

Such a slide guide unit 18a, 1
The main body portions 19a and 19b of 8b are fixed to the left and right side surfaces of the table 12 via adjustment liners 22 with bolts 21, respectively, and are attached so as to sandwich the bed 4 from both the left and right sides of the table 12. Table 1
Since the self-weight of No. 2 is not applied to the sliding surfaces 16a and 16b, the sliders 20a and 20b are provided with a lubricant between the sliding surfaces 16a and 16b so that a frictional force of a predetermined magnitude is generated.
Adjusting liner 2 so that it is pressed against a and 16b.
Adjust the thickness of 2 and slide guide units 18a, 18b
Is installed. The body portions 19a and 19b
Can be easily removed from the table 12 by pulling out the bolt 21.

As shown in FIG. 3, in this embodiment, two slide guide units 18a and 18b are arranged on one side surface of the table 12, and four slide guide units are arranged on both sides. In this case, in order to appropriately increase the damping property of the table feed system, the number of slide guide units 18a and 18b arranged, the width dimension of the main body portions 19a and 19b, and the pressing force of the sliders 20a and 20b are set. The arrangement of such a slide guide unit is common to both the Y-axis guide and the Z-axis guide.

2. Y-axis guide Next, FIG. 4 is a side view showing the positional relationship between the cross rail 6 and the saddle 8, showing the mounting position of the hybrid guide used as the Y-axis guide for guiding the feeding movement of the saddle 8 on the cross rail 6. Show.

A pair of guide rails 35a and 35b for rolling guides are provided on the upper and lower sides of the cross rail 6 to form the Y-axis ball screw 3.
The cross rail 6 is laid so as to extend parallel to the cross rail 4, and extends in the longitudinal direction of the cross rail 6, that is, in the horizontal direction. Rolling guide units 36a and 36b attached to the saddle 8 are engaged with the guide rails 35a and 35b, respectively.

As a guide for sending the saddle 8 in the horizontal direction, as in the case of the X-axis guide, the rolling guide constitutes a main guide surface that serves as a reference for the linear movement of the saddle 8, and the following slide guides are provided. Is provided as a follow-up guide.

Above and below the cross rail 6, sliding surfaces 37a and 37b extending parallel to the guide rails 35a and 35b.
Are formed. The sliding surfaces 37a and 37b are perpendicular to the guide surface of the rolling guide. The slide guide units 38a, 38b have sliders 39a, 39b that slide on the sliding surfaces 37a, 37b and body portions 40a, 40b, and the body portions 40a, 40b are the adjustment liners 42a, 4b.
The sliders 39a and 39b are fixed to the upper and lower surfaces of the saddle 8 with bolts or the like with the slider 2a sandwiched between the sliders 39a and 39b with a lubricant interposed therebetween. The frictional force of a predetermined magnitude is generated by being in pressure contact with 37b.

3. Z-Axis Guide Next, FIG. 5 is a top view showing the positional relationship between the column 2 and the cross rail 6 from the feed direction of the cross rail 6, and shows the mounting position of the hybrid guide used as the Z axis guide.

A pair of rolling guide guide rails 44a and 44b are laid on the cross rail 6 so as to extend in the vertical direction in parallel with the Z-axis ball screws 45a and 45b. Rolling guide units 46a and 46b attached to the back surface of the cross rail 6 are engaged with the guide rails 44a and 44b, respectively.

In the Z-axis guide as well, similar to the X-axis guide and the Y-axis guide, the rolling guide constitutes a main guide surface that serves as a reference for the linear movement of the cross rail 6, and the following slide guide follows. It is provided as a guide.

On the left and right of the cross rail 6, sliding surfaces 47a and 47b extending parallel to the guide rails 44a and 44b.
Are formed. The sliding surfaces 47a and 47b are perpendicular to the guide surface of the rolling guide. The slide guide units 48a and 48b have sliders 49a and 49b that slide on the slide surfaces 47a and 47b and main bodies 50a and 50b. The main bodies 50a and 50b are crossed with bolts or the like with the adjustment liner 52 interposed therebetween. It is fixed to the left and right side surfaces of the rail 6, and by adjusting the thickness of the adjustment liner 52, the sliders 49a and 49b are brought into pressure contact with the sliding surfaces 47a and 47b with a lubricant interposed therebetween, and a predetermined value is obtained. The frictional force of the magnitude of is generated.

Next, the operation and effect of this embodiment will be described.

In the machine tool of this embodiment, the X axis, the Y axis,
Since the hybrid guide in which the rolling guide and the sliding guide are combined is used for all the linear axes of the Z axis, the following effects can be obtained.

1. When the table 12 is fed during the individual effect processing, the rollers of the rolling guide units 15a and 15b are guided by the guide rails 14a and 14b.
The linear motion of the table 12 is mainly guided by rolling guides by rolling a and 14b. Slip surface 16a, 1
The weight of the table 12 is not applied to 6b and is for adding damping as will be described later, and therefore does not hinder the high speed of rolling guide. Therefore, it is possible to cope with fast cutting feed by utilizing the high speed characteristic of the rolling guide. Moreover, while the table 12 is exercising,
Appropriate frictional force is generated between the sliding surfaces 16a, 16b forming the sliding guide and the sliders 20a, 20b, which increases damping in the feed direction, so that cutting vibration generated during machining can be damped. Further, the waving in the left-right direction with respect to the moving direction of the table which occurs in the rolling guide can be suppressed by the slide guide units 18a and 18b.

Similarly, when the saddle 8 is fed during processing, the rolling guide composed of the rolling guide units 36a and 36b and the guide rails 35a and 35b is mainly used for the saddle 8.
Guides you and makes use of its high speed,
By the frictional force between the sliders 7a and 37b and the sliders 39a and 39b, the damping property in the feed direction can be increased, and the waving in the vertical direction can be suppressed.

As for the cross rail 6, the cross rail 6 is made use of the high speed of the rolling guide including the rolling guide units 46a and 46b and the guide rails 44a and 44b.
Can be sent at high speed, and the damping force can be increased by the frictional force between the sliding surfaces 47a, 47b and the sliders 49a, 49b, and the waving in the lateral direction can be suppressed.

As described above, since the damping property can be synergistically improved for all linear axes and the waving can be suppressed, it is possible to improve the quality such as the surface accuracy and the shape accuracy of the workpiece for processing the complicated three-dimensional free-form surface. In addition, it is possible to protect the tool and the machine from vibration and improve the tool life and the life of the entire machine.

2. Overall effect The guides for all X-axis, Y-axis, and Z-axis linear axes are hybrid guides that combine rolling guides and sliding guides, so that the sliding guides have almost the same friction characteristics and damping characteristics for each axis. It becomes easy to have.

Further, the parts of the rolling guide unit and the slide guide unit of each axis and the lubrication unit can be shared, and the parts cost is reduced and the slide guide unit is mounted at a place where it can be easily operated from the outside. ,
It has the effects of improving maintainability and shortening the control tuning time.

Contrary to the above, by adopting hybrid guides for all linear axes of the X axis, Y axis and Z axis,
By changing the preload of the rolling guide and the lubricant for each linear axis, and adjusting the friction characteristics between the slider and the sliding surface individually, it is possible to reduce the error caused by the difference in the loaded weight. It is also possible to design and manufacture a well-balanced and flexible guide system as a whole, such as by designing the shaft with large vibrations to increase damping.

In the above, the present invention has been described by using the hybrid guide in which the rolling guide and the slide guide are combined as an embodiment. However, instead of the slide guide, a hybrid guide including a combination of a static pressure guide and a rolling guide may be used. it can.

[0044]

As is apparent from the above description, according to the present invention, it is possible to systematically enhance the motion accuracy and damping property of the entire machine, and conversely, the damping property depending on individual conditions. Can be increased for a particular axis and can be improved in a well-balanced manner.

[Brief description of drawings]

FIG. 1 is an outline view of an embodiment of a machine tool having a hybrid guide mechanism according to the present invention.

FIG. 2 is a front view showing a table feed X-axis hybrid guide mechanism.

FIG. 3 is a side view of the table shown in FIG.

FIG. 4 is a side view showing a saddle-feeding Y-axis hybrid guide mechanism.

FIG. 5 is a top view showing a cross rail feed Z-axis hybrid guide mechanism.

[Explanation of symbols]

2 columns 4 beds 6 cross rail 8 saddle 10 spindle head 12 tables 13 Ball screw 14a, 14b Guide rail 15a, 15b Rolling guide unit 16a, 16b Sliding surface 18a, 18b slide guide unit 20a, 20b slider 22 Adjustment liner 24a, 24b Slip surface 26a, 26b Slip guide unit 28a, 28b slider 35a, 35b Guide rail 36a, 36b Rolling guide unit 37a, 37b Sliding surface 38a, 38b Slip guide unit 39a, 39b slider 40a, 40b main body 42a, 41b Adjustment liner 47a, 47b Slip surface 48a, 48b slide guide unit 49a, 49b slider

─────────────────────────────────────────────────── ─── Continuation of front page (51) Int.Cl. ⁷ Identification code FI theme code (reference) F16C 32/00 F16C 32/06 A 32/06 B23Q 1/26 Z 1/02 W (72) Inventor Far Katsuhito Fuji, 2068, Ooka, Numazu, Shizuoka Prefecture 3 68, Toshiba Machinery Co., Ltd. (72) Inventor Yoshiaki Kai, Numazu City, Shizuoka Prefecture 2068, 3 Ooka, Toshiba Machinery Co., Ltd. (72) Koichi Usami, Numazu, Shizuoka Prefecture Ooka 2068-3 Toshiba Machine Co., Ltd. In-house (72) Inventor Kazuhiro Sawa Hiroshi Ooka 2068-3, Numazu City, Shizuoka Prefecture Toshiba Machine Co., Ltd. (72) Inventor Toshiyuki Yokoyama 2068-3 Ooka, Numazu City, Shizuoka Prefecture Toshiba Machine Stock In-company (72) Inventor Takahiro Kugimoto 2068 Ooka, Numazu-shi, Shizuoka 3 F0 term in Toshiba Machine Co., Ltd. (reference) 3C048 BB01 BB03 BC01 CC00 DD01 EE10 3J102 AA02 AA09 BA07 BA09 BA12 CA02 CA11 CA20 GA07 3J104 AA01 AA44 AA52 AA65 AA67 AA69 AA74 AA76 AA79 BA64 DA02 DA13 DA20 EA01

Claims (3)

[Claims] 1. A machine tool having a table, a saddle, a spindle head, and a plurality of other linear axes that respectively give a linear motion to a moving body. In all the linear axes, a rolling guide and a sliding guide are provided in a moving body guide mechanism. Alternatively, a machine tool having a hybrid guide mechanism characterized by using a hybrid guide which is a combination of rolling guide and static pressure guide. 2. The hybrid guide is a combination of a rolling guide which constitutes a main guide serving as a linear motion reference on a base of a moving body and a sliding guide which serves as a secondary guide which complements the rolling guide. Claim 1 characterized by the above-mentioned.
A machine tool having the hybrid guide mechanism described in 1. 3. A machine tool having a hybrid guide mechanism according to claim 2, wherein the slide guide has a slide guide surface which is perpendicular to a guide surface of the rolling guide.