CN113272098B

CN113272098B - Feeding device of machine tool

Info

Publication number: CN113272098B
Application number: CN202080008407.2A
Authority: CN
Inventors: 高野和雅; 梶川真吾; 矶崎泰佑; 杉田直彦; 木崎通; 柏原翔一
Original assignee: Makino Milling Machine Co Ltd; University of Tokyo NUC
Current assignee: Makino Milling Machine Co Ltd; University of Tokyo NUC
Priority date: 2019-01-18
Filing date: 2020-01-14
Publication date: 2023-05-05
Anticipated expiration: 2040-01-14
Also published as: DE112020000272T5; JP2020116648A; JP7113431B2; WO2020149268A1; CN113272098A

Abstract

A feeding device (FS 2) for a machine tool is provided with a linear motion rolling guide (L2) and a ball screw mechanism (BS 2), wherein the linear motion rolling guide (L2) is arranged between a base member (2) and a moving body (3), and guides the movement of the moving body (3) relative to the base member (2); the ball screw mechanism (BS 2) drives the moving body (3) relative to the base member (2), the ball screw mechanism (BS 2) has a screw (S2), a nut (N2) and a screw holder (B2), the nut (N2) moves along the screw (S2), the screw holder (B2) is fixed relative to the base member (2) and supports the screw (S2), and the CFRP material (50) is sandwiched between the screw holder (B2) and the base member (2).

Description

Feeding device of machine tool

Technical Field

The present invention relates to a feeding device for a machine tool.

Background

In the field of machine tools, various structures for reducing vibrations have been proposed. For example, patent document 1 discloses an optical scanning type laser processing machine as a machine tool. The machine tool includes a bed, a cross member that moves on the bed, a saddle that moves on the cross member, and a machining head that is supported by the saddle. In this machine tool, CFRP (carbon fiber reinforced plastic) is used as the entire beam. With this structure, the vibration is reduced while achieving light weight and high rigidity.

[ Prior Art literature ]

[ patent literature ]

Japanese patent application laid-open No. 2000-263356 (patent document 1)

Disclosure of Invention

Problems to be solved by the invention

Generally, various vibrations occur in a machine tool. These include, for example, (1) vibration due to unbalance of the rotating spindle, (2) vibration due to intermittent cutting force, (3) vibration due to regenerative chatter, and (4) vibration due to reaction force acting on the base member when the moving body starts or stops moving. (1) Of the vibrations generated by unbalance of the rotating spindle, the spindle vibration is mainly. In addition, (2) the vibration due to the intermittent cutting force mainly vibrates the spindle and the table. In addition, (3) the vibration caused by the regenerative chatter is mainly the vibration of the tool. These spindles, tables and tools are relatively light in weight and are located at the end of the machine tool. Therefore, the vibration of these components is less likely to cause the vibration of a large displacement of the base member, which is relatively heavy in weight and is located below the machine tool, at a lower frequency than the weight of the machine tool. In contrast, (4) vibration is generated by a reaction force acting on the base member due to the movement of the moving body, and the reaction force directly acts on the base member via the rolling guide and the ball screw, so that large displacement vibration of the base member at a low frequency is easily caused. In recent years, high-speed machining has been frequently performed, and a moving body moves at a high acceleration and a high deceleration. Therefore, there are cases where: the base member is vibrated by a reaction force caused by the operation of the movable body, and the quality of the machined surface of the workpiece is deteriorated. In dealing with such a problem, it is considered to increase rigidity by making the base member heavy. However, this is not preferable because it increases the weight of the entire machine tool. As in the machine tool of patent document 1, CFRP may be used as a whole for a movable body such as a cross beam. However, CFRP is relatively low in rigidity in directions other than the direction of fibers, so that CFRP is used as a whole as a moving body, which may cause a decrease in static rigidity.

The invention provides a feeding device of a machine tool, which has high static rigidity and can reduce vibration displacement of a base component caused by counter force generated when a moving body starts or stops moving.

Means for solving the problems

One aspect of the present disclosure is a feeder for a machine tool that guides and feeds a moving body relative to a base member, the feeder including a linear motion rolling guide that is disposed between the base member and the moving body and guides movement of the moving body relative to the base member, and a ball screw mechanism; the ball screw mechanism drives the moving body with respect to the base member, and includes a screw, a nut that moves along the screw, and a screw holder that is fixed with respect to the base member and supports the screw, and a CFRP material is interposed between the screw holder and the base member.

In the feeder of the machine tool according to the aspect of the present disclosure, the CFRP material is sandwiched between the screw holder and the base member of the ball screw mechanism. The present inventors have found that vibration displacement of the base member due to reaction force generated when the moving body starts or stops moving can be reduced without changing the material of the base member or the moving body by sandwiching the CFRP material at this position. Therefore, the vibration displacement of the base member can be reduced while maintaining high static rigidity.

And a CFRP material is sandwiched between the linear motion rolling guide and the base member. In this case, the vibration displacement of the base member can be further reduced. In this case, the linear motion rolling guide includes a rail and a carriage that moves along the rail, and the CFRP material is sandwiched between the rail and the base member or between the carriage and the base member.

The screw holder includes first and second bearing bracket units arranged at intervals along the screw, and the CFRP material is fully covered in a range including the first and second bearing bracket units. In this case, since the CFRP material is fully spread between the first and second bearing bracket units, the vibration displacement of the base member can be further reduced.

The CFRP material includes a plurality of layers each containing carbon fibers in a predetermined direction, and the plurality of layers are laminated so that the orientation of the carbon fibers becomes ±45° with respect to the moving direction of the moving body. In this case, the CFRP material has high rigidity with respect to the all direction in the plane including the moving direction of the moving body.

The base member is made of an aluminum alloy. In this case, the base member can be made lightweight.

[ Effect of the invention ]

According to one aspect of the present disclosure, a feeder device for a machine tool that has high static rigidity and can reduce vibration displacement of a base member due to reaction force generated when a moving body starts or stops moving can be provided.

Drawings

Fig. 1 is a front view showing a machine tool having a feeder according to an embodiment.

Fig. 2 is a plan view showing the machine tool of fig. 1.

Fig. 3 is a side view showing the machine tool of fig. 1.

Fig. 4 is an enlarged side view showing the feeding device.

Fig. 5 is an enlarged front view showing the feeding device.

Fig. 6 is a view in cross section from VI-VI in fig. 5.

Fig. 7 is a graph showing an example of the experimental results.

Fig. 8 (a) is a graph showing the vibration damping state of the aluminum alloy. (b) is a graph showing the vibration damping state of the CFRP.

Detailed Description

Preferred modes for carrying out the invention

Hereinafter, a feeder of a machine tool according to an embodiment will be described with reference to the drawings. The same or corresponding elements are denoted by the same reference numerals, and repetitive description thereof will be omitted. For easy understanding, the scale of the drawing may be changed.

Fig. 1 is a front view showing a machine tool having a feeder according to an embodiment. Fig. 2 and 3 are a top view and a side view, respectively, of the machine tool of fig. 1. Referring to fig. 1, a machine tool 100 may be, for example, a vertical machining center. Machine tool 100 may be another machine tool. The machine tool 100 includes a bed 1, a slide 2, a saddle 3, a ram 4, a spindle head 5, a spindle 6, and a table 7. The machine tool 100 may further include other components.

In the present embodiment, the spindle 6 rotates about a vertical axis Os. In machine tool 100, a direction Z-axis direction (may also be referred to as an up-down direction) along axis Os. Referring to fig. 2, in the machine tool 100, the direction in which the slide 2, saddle 3, ram 4, and spindle head 5 are arranged in the horizontal direction is the Y-axis direction (may also be referred to as the front-rear direction). The saddle 3, the ram 4, and the spindle head 5 are located on the front side of the slide 2, and on the opposite side thereof are located on the rear side. Further, in the machine tool 100, a direction perpendicular to the Y-axis direction among the horizontal directions is an X-axis direction (may also be referred to as a left-right direction).

Referring to fig. 1, a bed 1 has a foundation 11 and a main body 12. The foundation 11 is disposed on the floor surface of a factory or the like. The main body 12 is disposed above the foundation 11. The main body 12 has a pair of side walls 12a and a top wall 12b provided at an upper portion of the pair of side walls 12 a. The pair of side walls 12a are disposed so as to face each other in the X-axis direction. The top wall 12b joins upper portions of the pair of side walls 12 a.

Referring to fig. 2, the slider 2 rides on the upper surfaces of a pair of side walls 12a of the bed 1. In the present embodiment, the slider 2 is made of an aluminum alloy for weight reduction. The slide 2 is driven in the Y-axis direction on the bed 1 by the feeding device FS 1. That is, in the relationship between the bed 1 and the slider 2, the slider 2 functions as a "moving body" that moves in a predetermined direction (Y-axis direction), and the bed 1 functions as a "base member" that supports the moving body. The feeding device FS1 has 1 or more (a pair in the present embodiment) linear-motion rolling guides L1, a ball screw mechanism BS1, and a motor M1.

Referring to fig. 3, a linear motion rolling guide L1 is disposed between the bed 1 and the slider 2, and guides the movement of the slider 2 with respect to the bed 1. Each of the linear-motion rolling guides L1 includes a rail R1 and 1 or more (a pair in the present embodiment) carriages C1. In the feeding device FS1, the rail R1 is fixed to the upper surface of the bed 1 as the "base member", and the carriage C1 is fixed to the bottom surface of the slider 2 as the "moving body".

Referring to fig. 2, a ball screw mechanism BS1 drives a slider 2 with respect to a bed 1. The ball screw mechanism BS1 includes a screw S1, a nut N1, and a screw holder B1. The lead screw S1 is disposed with its central axis along the Y-axis direction. The screw holder B1 includes first and second bearing bracket units B1a (only one bearing bracket unit B1a is shown in the figure) arranged at a distance from each other along the screw S1. Each bearing-bracket unit B1a includes 1 or more rolling bearings and a bracket supporting the rolling bearings. The first and second bearing bracket units B1a can support both ends of the screw shaft S1, for example. The screw holder B1 is fixed to the top wall 12B of the bed 1. In other embodiments, the screw holder B1 may include only 1 bearing bracket unit B1a (for example, the screw S1 may be supported by a cantilever).

The nut N1 moves along the screw S1. The nut N1 is fixed to the bottom surface of the slider 2. The motor M1 is connected to one end of the screw shaft S1. The nut N1 and the slider 2 move in the Y-axis direction as the screw S1 is rotated by the motor M1. The feeding of the slider 2 in the Y-axis direction is controlled by an NC apparatus (not shown).

A saddle 3 is mounted on the front face of the slider 2. The saddle 3 is driven in the X-axis direction on the slide 2 by the feeding device FS2. That is, in the relationship between the slider 2 and the saddle 3, the slider 2 functions as a base member, and the saddle 3 functions as a moving body. The feeding device FS2 has 1 or more (a pair in the present embodiment) linear-motion rolling guides L2, a ball screw mechanism BS2, and a motor M2.

The linear motion rolling guide L2 is disposed between the slider 2 and the saddle 3, and guides the movement of the saddle 3 relative to the slider 2. Each of the linear-motion rolling guides L2 includes a rail R2 and 1 or more (a pair in the present embodiment) carriages C2. In the feeding device FS2, the rail R2 is fixed with respect to the front surface of the slider 2 as the "base member", and the carriage C2 is fixed with respect to the rear surface of the saddle 3 as the "moving body".

The ball screw mechanism BS2 drives the saddle 3 with respect to the slider 2. The ball screw mechanism BS2 includes a screw S2, a nut N2, and a screw holder B2. The screw S2 is disposed along the X-axis direction. The screw holder B2 includes first and second bearing bracket units B2a (see fig. 5) disposed at intervals along the screw S2. Each bearing-bracket unit B2a includes 1 or more rolling bearings and a bracket supporting the rolling bearings. The first and second bearing bracket units B2a can support both ends of the screw S2, for example. The screw holder B2 is fixed relative to the front face of the slider 2. In other embodiments, the screw holder B2 may include only 1 bearing bracket unit B2a (for example, the screw S2 may be supported by a cantilever).

Referring to fig. 2, the nut N2 moves along the screw S2. The nut N2 is fixed with respect to the rear of the saddle 3. The motor M2 is connected to one end of the screw shaft S2. The nut N2 and saddle 3 move in the X-axis direction as the screw S2 is rotated by the motor M2. The feeding of the saddle 3 in the X-axis direction is controlled by the NC apparatus.

Referring to fig. 3, the ram 4 is mounted on the front face of the saddle 3. The ram 4 is driven by the feeding device FS3 in the Z-axis direction on the saddle 3. That is, in the relation between the saddle 3 and the ram 4, the saddle 3 functions as a "base member", and the ram 4 functions as a "moving body". The feeding device FS3 has 1 or more (a pair in the present embodiment) linear-motion rolling guides L3, a ball screw mechanism BS3, and a motor M3.

The linear movement rolling guide L3 is disposed between the saddle 3 and the ram 4, and guides the movement of the ram 4 relative to the saddle 3. Each of the linear-motion rolling guides L3 includes a rail R3 and 1 or more (a pair in the present embodiment) carriages C3. In the feeding devices FS1 and FS2 described above, the rails R1 and R2 are fixed to the "base member", the carriages C1 and C2 are fixed to the "moving body", and in the feeding device FS3, the rail R3 is fixed to the rear surface of the ram 4 as the "moving body", and the carriage C3 is fixed to the front surface of the saddle 3 as the "base member".

The ball screw mechanism BS3 drives the ram 4 with respect to the saddle 3. The ball screw mechanism BS3 may include a screw (not shown) disposed in the Z-axis direction, a nut (not shown) fixed to the ram 4, and a screw holder B3. The screw holder B3 includes first and second bearing bracket units B3a (only one bearing bracket unit B3a is shown in the figure) arranged at a distance from each other along the screw. Each bearing-bracket unit B3a includes 1 or more rolling bearings and a bracket supporting the rolling bearings. The first and second bearing bracket units B3a can support both ends of the screw, for example. The screw holder B3 is fixed with respect to the front of the saddle 3. In other embodiments, the screw holder B3 may include only 1 bearing bracket unit B3a (for example, the screw may be supported by a cantilever). The motor M3 is connected to one end of the ball screw.

The nuts of the ball screw mechanism BS3 can be configured in the same manner as the nuts N1, N2 of the ball screw mechanisms BS1, BS2 described above, and thus the nuts and the ram 4 can move in the Z-axis direction as the screw is rotated by the motor M3. The feeding of the ram 4 in the Z-axis direction is controlled by the NC device.

Next, the feeding device FS2 between the slide 2 and the saddle 3 in the machine tool 100 will be described in detail.

Fig. 4 and 5 are an enlarged side view and an enlarged front view of the feeding device FS2, respectively. In fig. 4 and 5, several components (for example, saddle 3 and nut N2) are omitted for easy understanding. As shown in fig. 5, in the feeding device FS2, CFRP (carbon fiber reinforced plastic) material 50 is sandwiched between the screw holder B2 and the slider 2.

The CFRP material 50 is spread over a range including the first and second bearing bracket units B2 a. Specifically, in fig. 5, the CFRP material 50 is 1 sheet, and has a size capable of covering substantially the entire front surface of the slider 2. Thereby, the CFRP material 50 is fully laid between the first and second bearing bracket units B2a without a gap. Instead, the CFRP material 50 of fig. 5 may be divided into a plurality of plates. Instead, as shown in fig. 6, the CFRP material 50 may be disposed just below each of the first and second bearing bracket units B2 a. In this case, there is a space between the first and second bearing bracket units B2a where the CFRP material is not disposed.

Referring to fig. 5, the cfrp material 50 includes a plurality of layers. Each layer contains carbon fibers in a predetermined direction. Specifically, the plurality of layers are stacked so that the orientation 51 of the carbon fibers becomes ±45° with respect to the moving direction (X-axis direction) of the saddle 3. The CFRP material 50 can be fixed with respect to the slider 2 by a plurality of bolts 52, for example. The screw holder B2 can be fixed to the slider 2 by a plurality of bolts 53 together with the CFRP material 50. An adhesive may be used between the slider 2 and the CFRP material 50 and between the CFRP material 50 and the screw holder B2. The various specifications of the CFRP material 50 (for example, the thickness, modulus of elasticity such as young's modulus, tensile strength such as tensile strength, type of matrix resin, type of carbon fiber, carbon fiber content, and the like) can be appropriately determined in consideration of various factors such as the load associated with the CFRP material 50. These specifications can be set to, for example, a thickness (for example, 1 to 5 mm) that does not excessively decrease static rigidity, an orientation (for example, 0 °,90 °) that has high attenuation in a specific direction, and a thermosetting resin having high young's modulus in conformity with the mechanical feed axis design specification.

Referring to fig. 4, in the feeding device FS2, the CFRP material 60 is also sandwiched between the linear motion rolling guide L2 and the slider 2. Specifically, in the feeding device FS2, the CFRP material 60 is sandwiched between the rail R2 and the slider 2. The CFRP material 60, which may be, for example, a sheet of plate, may have a size that extends over substantially the entire length of the rail R2. Instead, the CFRP material 60 may be divided into a plurality of plates. The CFRP material 60 includes a plurality of layers, similar to the CFRP material 50 described above, which are laminated so that the orientation of the carbon fibers of the CFRP material 60 is ±45° with respect to the moving direction (X-axis direction) of the saddle 3.

Referring to fig. 5, the rail R2 can be fixed with respect to the slider 2 by a plurality of bolts 54 together with CFRP material 60 (not shown in fig. 5), for example. An adhesive may be used between the slider 2 and the CFRP material 60 and between the CFRP material 60 and the rail R2. The specifications of the CFRP material 60 may be appropriately determined in consideration of various factors such as the load on the CFRP material 60, and may be the same as the CFRP material 50.

Next, a reaction force acting on the slider 2 when the saddle 3 starts or stops moving will be described.

Fig. 6 is a view in cross section from VI-VI in fig. 5. In fig. 6, several components (e.g., motor M2, etc.) are omitted for ease of understanding. Fig. 6 shows a state when the saddle 3 stops moving to the right. In this state, torque acts on the saddle 3 by inertia so as to rotate the saddle 3 in the counterclockwise direction. Accordingly, a downward force F1 acts on the right carriage C2, and a counter force RF1 in the opposite direction acts on the slider 2. Further, an upward force F2 acts on the left carriage C2, and a reaction force RF2 in the opposite direction acts on the slider 2. Inertial forces F3 and F4 act on the first and second bearing bracket units B2a from the saddle 3 via the nut N2 and the screw S2, respectively, and reaction forces RF3 and RF4 in opposite directions act on the slider 2. The reaction forces RF1, RF2, RF3, and RF4 as described above can generate vibrations of the slider 2. In particular, the reaction forces RF3 and RF4 directly act on the slider 2 in the X-axis direction via the ball screw mechanism BS2, and thus the slider 2 is likely to vibrate at a low frequency with a large displacement. In a state where the saddle 3 starts to move rightward, the reaction forces RF1, RF2, RF3, and RF4 described above and the reaction force in the opposite direction act on the slider 2.

As described above, the reaction force as described above acts on the slider 2 when the saddle 3X starts or stops moving in the X-axis direction. The vibration of the slider 2 due to such a reaction force does not affect the quality of the machined surface of the workpiece when the tool attached to the spindle 6 is not rapidly fed or cut without coming into contact with the workpiece. However, in some machining, when a tool attached to the spindle 6 contacts a workpiece, the saddle 3 may start or stop movement in the X-axis direction (for example, angular machining including movement in the X-axis and Y-axis directions by an end mill, or scanning machining including movement in the X-axis and Z-axis directions by a ball end mill and repeating periodic feeding in the Y-axis direction, etc.). In such a case, the vibration of the slider 2 due to the reaction force may affect the quality of the machined surface of the workpiece.

In order to solve such a problem, the present inventors have found that, when the CFRP material 50 is inserted between the screw holder B2 and the slider 2 and the CFRP material 60 is inserted between the rail R2 and the slider 2, vibrations of the slider 2 due to the reaction forces RF1, RF2, RF3, and RF4 described above can be reduced by the

CFRP materials

50 and 60.

Specifically, the present inventors have found that, in the machine tool 100 described above, as shown in fig. 6, when the movement of the saddle 3 in the X-axis direction is stopped, the machine tool 100 has a mode in which the entire structure vibrates at a low frequency (in one example, about 30 Hz) in the X-axis direction. In order to investigate this mode, vibration test was performed in the machine tool 100. Specifically, an acceleration sensor is provided to a tool attached to the spindle 6, and the tip of the tool is vibrated in the X-axis direction. The test was performed under the condition that the

CFRP material

50, 60 was provided and under the condition that the

CFRP material

50, 60 was not provided.

Fig. 7 is a graph showing an example of the experimental results. The horizontal axis represents frequency and the vertical axis represents amplitude. As shown in fig. 7, it is understood that each of the condition Cn1 in which the

CFRP materials

50, 60 are provided and the condition Cn2 in which the

CFRP materials

50, 60 are not provided has a large peak at about 30 Hz. As shown in fig. 7, it is understood that the peak value of the condition Cn1 is reduced from the peak value of the condition Cn2 due to the presence of the

CFRP materials

50 and 60. From this result, it is also known that the

CFRP materials

50 and 60 can reduce the vibration displacement as a problem. Further, the displacement of the spindle 6 was measured by applying static loads in the X-axis, Y-axis and Z-axis directions between the spindle 6 and the table 7, and as a result, it was not seen that there was no difference in the presence or absence of the

CFRP materials

50, 60, and it was confirmed that there was no problem in rigidity.

As described above, in the feeder FS2 of the machine tool 100 according to the embodiment, the CFRP material 50 is sandwiched between the screw holder B2 of the ball screw mechanism BS2 and the slider 2. As described above, the present inventors have found that by sandwiching the CFRP material 50 between the portions, the vibration displacement of the slider 2 caused by the reaction forces RF1, RF2, RF3, and RF4 when the saddle 3 starts or stops moving in the X-axis direction can be reduced without changing the material of the slider 2 or the saddle 3. Therefore, the vibration displacement of the slider 2 can be reduced while maintaining high static rigidity.

In addition, in the feeding device FS2, the CFRP material 60 is sandwiched between the rail R2 of the linear motion rolling guide L2 and the slider 2. Therefore, the vibration displacement of the slider 2 can be further reduced.

In the feeder FS2, the screw holder B2 includes first and second bearing bracket units B2a arranged at intervals along the screw S2, and in the embodiment of fig. 5, the CFRP material 50 is spread over a range including the first and second bearing bracket units B2 a. Accordingly, the CFRP material is fully spread between the first and second bearing bracket units B2a without a gap, and the vibration displacement of the slider 2 can be further reduced.

In the feeder FS2, the CFRP material 50 includes a plurality of layers each containing carbon fibers in a predetermined direction, and the layers are stacked so that the orientation 51 of the carbon fibers becomes ±45° with respect to the moving direction (X-axis direction) of the saddle 3. Accordingly, the CFRP material 50 has high rigidity with respect to the all directions in the XZ plane including the moving direction of the saddle 3.

In the feeder FS2, the slider 2 is made of an aluminum alloy. Therefore, the slide 2 and the entire machine tool 100 can be made lightweight. Conventionally, in order to reduce vibration, the slider 2 as a base member is generally made of a heavy cast iron, but vibration can be reduced by sandwiching the

CFRP materials

50, 60, and it is no longer necessary to weight the base member. Further, although the Young's modulus is slightly inferior to that of cast iron, a lightweight metal material such as aluminum alloy can be used.

CFRP is a lightweight and highly rigid material, and therefore can increase the natural frequency of the structure. Fig. 8 (a) and (b) show vibration damping conditions of the aluminum alloy and CFRP, respectively. Since the period of the damping condition depends on the natural frequency, the vibration damping performance of the material having a high natural frequency also becomes high. Therefore, in the moving body sandwiching the CFRP material, vibration due to inertial force at the time of start and stop is suppressed.

The embodiment of the feeding device of the machine tool is described, but the present invention is not limited to the above embodiment. Various modifications to the above embodiments may be made by those skilled in the art. In addition, if a person skilled in the art is the case, the features included in 1 embodiment may be incorporated into other embodiments as long as no contradiction occurs, or may be exchanged with the features included in other embodiments.

For example, in the above-described embodiment, the

CFRP materials

50, 60 are used only for the feeding device FS2. However, in other embodiments, CFRP material may be used instead of or in addition to the feeding device FS1 and/or the feeding device FS3.

Specifically, referring to fig. 2, in the feeding device FS1, as described above, the slider 2 functions as a "moving body" that moves in a predetermined direction (Y-axis direction), and the bed 1 functions as a "base member" that supports the moving body. When the CFRP material is used for the feeder FS1, the CFRP material can be sandwiched between the bed 1 and the screw holder B1. The CFRP material may be sandwiched between the bed 1 and the rail R1. In this case, the vibration displacement of the bed 1 due to the reaction force generated when the slider 2 starts or stops moving in the Y-axis direction can be reduced.

Referring to fig. 3, in the feeding device FS3, the ram 4 functions as a "moving body" that moves in a predetermined direction (Z-axis direction), and the saddle 3 functions as a "base member" that supports the moving body. In the case where CFRP material is used for the feeding device FS3, CFRP material can be attached between the saddle 3 and the screw holder B3. In addition, CFRP material may be bonded between the saddle 3 and the carriage C3. In this case, the vibration displacement of the saddle 3 due to the reaction force generated when the ram 4 starts or stops moving in the Z-axis direction can be reduced.

Description of symbols

1: lathe bed (base parts)

2: slider (base, moving body)

3: saddle (base part, moving body)

4: pressure head (moving body)

50: CFRP material

51: orientation of CFRP materials

60: CFRP material

100: machine tool

B1, B2, B3: screw rod retainer

B1a, B2a, B3a: first and second bearing bracket unit

BS1, BS2, BS3: ball screw mechanism

C1, C2, C3: sliding frame

FS1, FS2, FS3: feeding device

L1, L2, L3: linear motion rolling guide

N1, N2, N3: nut

R1, R2, R3: rail track

S1, S2: and (5) a screw rod.

Claims

1. A feeding device for a machine tool, which guides a moving body relative to a base member and drives the moving body to feed, is characterized by comprising a linear motion rolling guide and a ball screw mechanism,

a linear motion rolling guide disposed between the base member and the movable body, the linear motion rolling guide guiding movement of the movable body relative to the base member;

the ball screw mechanism drives the moving body relative to the base member, and comprises a screw, a nut and a screw holder,

the nut is moved along the screw rod,

the screw holder is fixed to the base member and supports the screw,

the CFRP material is sandwiched between the screw holder and the base member.

2. The feeder of machine tool according to claim 1, wherein a CFRP material is sandwiched between the linear motion rolling guide and the base member.

3. The feeding device of a machine tool according to claim 1, wherein,

the screw holder includes first and second bearing bracket units arranged at intervals along the screw,

the CFRP material is spread over a range including the first and second bearing bracket units.

4. The feeder of a machine tool according to claim 1 or 2, wherein the CFRP material includes a plurality of layers each including carbon fibers in a predetermined direction, and the plurality of layers are stacked so that an orientation of the carbon fibers becomes ±45° with respect to a moving direction of the moving body.

5. The feeder of machine tool according to claim 1, wherein the base member is made of an aluminum alloy.