JP2015182199A - Thermal deformation prevention structure of machine tool, and machine tool equipped with the same - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a thermal deformation prevention structure of a machine tool in which a temperature difference can be reduced, between respective parts of the structure due to a heating element of the machine tool and ambient temperature change, and thermal deformation of the structure is effectively prevented, thereby the high accuracy of the machine tool can be achieved.SOLUTION: A thermal deformation prevention structure 1 of a machine tool 2 of the present invention has: hollow columnar structures 14, 16 provided so as to be extended in the vertical direction and constituting a portion of the machine tool; a liquid receiving unit 40 formed in the inside of the structure and receiving liquid 38; and thermal deformation prevention means for reducing a temperature difference between respective parts of the structure by equalizing a liquid temperature of the liquid received in the liquid receiving unit over the whole liquid receiving unit and preventing thermal deformation of the structure. The thermal deformation prevention means includes stirring means 42 for stirring the liquid in the liquid receiving unit, and heat transfer enhancement means R provided in an inner circumferential surface of the liquid receiving unit and promoting the liquid movement in the liquid receiving unit.

Description

  The present invention relates to a thermal deformation prevention structure for a machine tool, and a machine tool including the same, and more particularly, to a thermal deformation prevention structure for a machine tool that prevents thermal deformation due to a heating element of the machine tool or a change in ambient temperature, and And a machine tool provided with the same.

Conventionally, cast iron and steel are generally used for structures constituting machine tools. However, thermal deformation occurs due to changes in the temperature of the structure, and positioning accuracy, straightness accuracy, squareness accuracy, etc. Getting worse. Examples of factors that cause the temperature of the structure to change in this way include changes in ambient temperature and heat generation of the machine tool itself.
In addition, machine tools are generally installed in buildings, but there is a problem that the room temperature changes according to the outside air temperature. Air conditioning management is performed to minimize such room temperature changes. Even when the door is open, there is a problem that it is difficult to eliminate the room temperature change by opening and closing the door.
Furthermore, there is a problem that equipment and parts such as motors and bearings that drive the machine tool generate heat, and heat is transmitted to the machine tool structure, and cooling fluid is circulated in the machine tool heating element. In many cases, there is also a problem that it is difficult to eliminate the transfer of heat to the structure.
The speed of temperature changes in machine tool structures is determined by the temperature difference from the outside, the ease of heat transfer from the structure (heat conductivity and heat transfer coefficient), and the heat capacity. Is influenced by the environment where the machine tool is located. In particular, the ease of heat transfer and the heat capacity are affected by the material and volume of the structure and peripheral elements. Furthermore, in actual machine tools, uneven temperature changes occur for each part, so the cost and weight of the machine tool are restricted despite the fact that complex deformation including bending of the structure occurs. The inside of the body is often a cavity (air), and there is a problem that it is difficult to eliminate the temperature difference that occurs between the parts.

On the other hand, as a technique for suppressing changes in the ambient temperature of the machine tool and the temperature of the heating element, a method of attaching a heat insulating plate having a low thermal conductivity to the structure is also known. In particular, in a columnar or beam-like structure, there is a serious problem that bending deformation is likely to occur due to a temperature difference between parts. For example, heat is generated in the front-rear direction or the left-right direction of a columnar structure extending in the vertical direction. There is also a method for suppressing thermal deformation by providing a heat insulating plate so that the way of transmission is uniform.
However, in such a method, since the inside of the structure is hollow and the temperature difference between each part of the structure cannot be effectively reduced, the thermal deformation of the structure can be sufficiently suppressed. In addition, there is a problem that the accuracy required in the machine tool cannot be sufficiently achieved, and the size and installation space of the structure itself are limited by the provision of a heat insulating plate outside the structure. There is also.

Therefore, as another form of the thermal deformation prevention structure for preventing thermal deformation of the machine tool, for example, as described in Patent Document 1 and Patent Document 2, a hollow columnar structural member constituting the machine tool is used. A structure in which a hollow portion of a structure is filled with a liquid such as water or oil is also known. In patent document 1, the structure with respect to an external temperature change is carried out by blowing and circulating the gas in the liquid in the hollow part of a structure, and in patent document 2, natural convection of the liquid in the hollow part of a structure, respectively. The temperature difference between each part of a member is reduced and the thermal deformation of a structure is suppressed.
However, as described in Patent Document 1, gas is blown into the liquid in the hollow portion of the structure, or the natural convection of the liquid is used as described in Patent Document 2, so that the structure There is a region where the liquid contained in the hollow part of the body is difficult to be stirred, and the liquid is not sufficiently stirred, and it is difficult to efficiently equalize the temperature of the liquid over the entire hollow part. is there.

  Further, Patent Document 3 discloses that the temperature of each part of the bed is obtained by filling a liquid in a cavity formed in the entire bed serving as a base of a machine tool and circulating the liquid with a pump through a pipe. Also disclosed is one that equalizes the above. However, Patent Document 3 only describes a bed arranged so as to extend in the horizontal direction of the machine tool, and is provided so as to extend in the vertical direction of the machine tool. There is no disclosure or suggestion of a thermal deformation prevention structure related to a hollow columnar structure that is prone to occur.

Japanese Patent Laid-Open No. 61-111866 Japanese Patent Laid-Open No. 61-111867 JP 2004-66437 A

  Therefore, the present invention has been made to solve the above-described problems of the prior art, and can reduce the temperature difference between each part of the structure due to a heating element of the machine tool and the surrounding temperature change, An object of the present invention is to provide a structure for preventing thermal deformation of a machine tool that can effectively prevent thermal deformation of the structure and realize high accuracy of the machine tool.

In order to achieve the above object, the present invention provides a thermal deformation prevention structure for a machine tool that prevents thermal deformation due to a temperature change of a heating element of the machine tool and the surroundings, and is provided so as to extend in the vertical direction. A hollow columnar structure that forms part of the machine, a liquid storage part that is formed inside the structure and stores the liquid, and the temperature of the liquid stored in the liquid storage part A thermal deformation preventing means for preventing thermal deformation of the structure by reducing the temperature difference between the parts of the structure by homogenizing over the whole, and the thermal deformation preventing means, Stirring means for stirring the liquid in the liquid storage section; and heat transfer promotion means provided on the inner peripheral surface of the liquid storage section for promoting movement of the liquid in the liquid storage section or heat exchange with the liquid. It is characterized by having.
In the present invention configured as above, the liquid in the liquid storage portion of the structure is stirred by the stirring means of the thermal deformation prevention means, and the heat transfer of the thermal deformation prevention means provided on the inner peripheral surface of the liquid storage portion The promotion means can promote the movement of the liquid in the liquid container or the heat exchange with the liquid. Thereby, the temperature of the liquid stored in the liquid storage part is made uniform over the entire liquid storage part, and the temperature difference between the respective parts of the structure due to the heating element of the machine tool and the surrounding temperature change can be reduced. It is possible to effectively prevent thermal deformation of the structure. Therefore, high accuracy of the machine tool can be realized.

In the present invention, preferably, the stirring means of the thermal deformation preventing means includes an impeller that is provided in the liquid storage portion and rotates to stir the liquid.
In the present invention configured as described above, since the impeller which is the stirring means of the thermal deformation preventing means rotates, the liquid in the liquid storage section of the structure can be effectively stirred, so the liquid storage section The temperature of the liquid accommodated in the liquid can be effectively equalized over the entire liquid accommodating portion. Therefore, it is possible to reliably reduce the temperature difference between the respective parts of the structure due to the temperature change of the heating element of the machine tool and the surroundings, and to prevent thermal deformation of the structure more effectively.

In the present invention, preferably, the heat transfer promoting means of the thermal deformation preventing means includes a curved surface that forms a corner portion of the inner peripheral surface of the liquid storage portion in an arc shape.
In the present invention configured as described above, the heat transfer promoting means of the thermal deformation preventing means includes a curved surface that forms a corner of the inner peripheral surface of the liquid storage portion in an arc shape, so that stirring is performed by the stirring means. It is possible to smoothly move the liquid in the liquid storage portion and to promote the stirring of the liquid effectively. Therefore, the temperature of the liquid stored in the liquid storage unit can be more effectively equalized over the entire liquid storage unit. Therefore, while ensuring the strength and weight of the structure, it is possible to more reliably reduce the temperature difference between each part of the structure due to changes in the temperature of the heating element of the machine tool and the surroundings, further reducing the thermal deformation of the structure. It can prevent more effectively.

In the present invention, it is preferable that the heat transfer promoting means of the thermal deformation preventing means includes a spiral rib that protrudes inward from the inner peripheral surface of the liquid storage portion and is spirally formed along the circumferential direction. May be.
In the present invention configured as described above, the heat transfer promoting means of the thermal deformation preventing means includes a spiral rib that protrudes inward from the inner peripheral surface of the liquid storage portion and is spirally formed in the circumferential direction. By providing, the liquid in the liquid storage unit being stirred by the stirring means can be smoothly moved along the spiral ribs and circulated in the vertical direction in the liquid storage unit. It can be effectively promoted. In addition, since the convection of the liquid is effectively spread over the entire liquid storage portion of the structure, the temperature of the liquid stored in the liquid storage portion can be more effectively equalized. Therefore, while ensuring the strength and weight of the structure, it is possible to more reliably reduce the temperature difference between each part of the structure due to changes in the temperature of the heating element of the machine tool and the surroundings, further reducing the thermal deformation of the structure. It can prevent more effectively.

In the present invention, preferably, the heat transfer promoting means of the thermal deformation preventing means includes a plurality of vertical ribs formed so as to protrude inward from the inner peripheral surface of the liquid storage portion and extend in the longitudinal direction of the structure. You may have.
In the present invention configured as described above, the plurality of vertical ribs formed so that the heat transfer promoting means of the thermal deformation preventing means protrudes inward from the inner peripheral surface of the liquid storage portion and extends in the longitudinal direction of the structure. Since the surface area of the inner peripheral surface of the liquid storage portion is increased as compared with the case where no vertical rib is provided, heat exchange between the liquid in the liquid storage portion being stirred by the stirring means and the vertical rib The amount can be increased. Therefore, since the temperature of the liquid stored in the liquid storage portion can be more effectively equalized while ensuring the strength and weight of the structure, the structure is generated by the heating element of the machine tool or the surrounding temperature change. The temperature difference between these parts can be reduced more reliably, and the thermal deformation of the structure can be more effectively prevented.

In the present invention, preferably, the stirring means of the thermal deformation preventing means may include a pump that circulates the liquid in the liquid container by pumping.
In the present invention configured as described above, since the liquid in the liquid storage portion of the structure can be effectively stirred by pumping the pump that is the stirring means of the thermal deformation prevention means, the liquid is stored in the liquid storage portion. The temperature of the liquid can be effectively equalized over the entire liquid container. Therefore, it is possible to reliably reduce the temperature difference between the respective parts of the structure due to the temperature change of the heating element of the machine tool and the surroundings, and to prevent thermal deformation of the structure more effectively.

In the present invention, preferably, the liquid container is sealed by a sealing means.
In the present invention configured as described above, since the liquid storage portion is sealed by the sealing means, the liquid in the liquid storage portion can be prevented from evaporating to the outside, and the maintenance burden can be reduced. it can.

In the present invention, preferably, the stirring means of the thermal deformation preventing means includes an aeration device that circulates by supplying air to the liquid in the liquid storage portion, and the upper portion of the liquid storage portion is open to the atmosphere.
In the present invention configured as described above, the aeration apparatus, which is the stirring means of the thermal deformation prevention means, supplies air to the liquid in the liquid storage section and circulates it, so that the liquid in the liquid storage section of the structure is effectively used. Therefore, the temperature of the liquid stored in the liquid storage part can be effectively uniformed over the entire liquid storage part. Therefore, it is possible to reliably reduce the temperature difference between the respective parts of the structure body due to changes in the temperature of the heating element of the machine tool and the surroundings, and it is possible to more effectively prevent the thermal deformation of the structure body.

In this invention, Preferably, the liquid in the said liquid accommodating part is the water containing the additive which has antiseptic and rust prevention property.
In the present invention configured as described above, since the liquid in the liquid storage portion is water containing an additive having antiseptic and rust prevention properties, the corrosion of the liquid itself and the corrosion of the liquid storage portion of the structure are suppressed. can do. Therefore, it is possible to suppress the frequency of replacement of liquid due to corrosion and replacement of the liquid container, and to reliably reduce the temperature difference between each part of the structure due to the heating element of the machine tool and the surrounding temperature change. It is possible to effectively prevent the thermal deformation of the machine tool and achieve high accuracy of the machine tool.

In the present invention, preferably, the liquid in the liquid storage part is oil, and the stirring means of the thermal deformation prevention means may include an oil cooler circulation device that cools and circulates the oil in the liquid storage part. Good.
In the present invention configured as described above, the oil cooler circulation device, which is the stirring means of the thermal deformation prevention means, cools and circulates the oil in the liquid storage section, so that the oil in the liquid storage section of the structure is effectively used. And the temperature of the oil stored in the liquid storage section can be effectively uniformed over the entire liquid storage section. Therefore, it is possible to reliably reduce the temperature difference between the respective parts of the structure due to the temperature change of the heating element of the machine tool and the surroundings, and to prevent thermal deformation of the structure more effectively.

In the present invention, preferably, the structures are a first structure and a second structure which are formed so as to extend in the up-down direction and are spaced apart from each other in the horizontal direction to form a pair. Each of the first structure and the second structure is provided with the liquid storage portion and the thermal deformation prevention means.
In the present invention configured as above, each of the structures of the first structure and the second structure which are formed so as to extend in the vertical direction and form a pair arranged at intervals in the horizontal direction. Since the liquid storage portion and the thermal deformation preventing means are respectively provided in the thermal deformation of each structural body itself, it is possible to more effectively prevent the thermal deformation of each structure itself, and to achieve high accuracy of the machine tool.

Moreover, this invention is a machine tool provided with the said thermal deformation prevention structure.
In the present invention configured as described above, it is possible to reliably reduce the temperature difference between each part of the structure due to the temperature change of the heating element of the machine tool and the surrounding temperature, and effectively prevent the thermal deformation of the structure. can do. Therefore, high accuracy of the machine tool can be realized.

  According to the structure for preventing thermal deformation of a machine tool of the present invention, it is possible to reduce the temperature difference between the respective parts of the structure due to the temperature change of the heating element of the machine tool and the surroundings, thereby effectively preventing the thermal deformation of the structure. It is possible to achieve high accuracy of the machine tool.

It is the schematic perspective view which looked at the machine tool incorporating the thermal deformation prevention structure by 1st Embodiment of this invention from diagonally forward. It is front sectional drawing which shows the thermal deformation prevention structure by 1st Embodiment of this invention. In the column structure of the thermal deformation prevention structure according to the first embodiment of the present invention, FIG. In the column structure of the thermal deformation prevention structure by 2nd Embodiment of this invention, it is the partial expansion perspective view which fractured | ruptured partially and expanded so that the inner peripheral part could be seen. In the column structure of the thermal deformation prevention structure by 3rd Embodiment of this invention, it is the partial expansion perspective view which fractured | ruptured and expanded so that an inner peripheral part could be seen. It is front sectional drawing which shows the thermal deformation prevention structure by 4th Embodiment of this invention. It is front sectional drawing which shows the thermal deformation prevention structure by 5th Embodiment of this invention. It is front sectional drawing which shows the thermal deformation prevention structure by 6th Embodiment of this invention.

Hereinafter, with reference to FIGS. 1-3, the thermal deformation prevention structure by 1st Embodiment of this invention is demonstrated.
First, FIG. 1 is a schematic perspective view of a machine tool incorporating a thermal deformation prevention structure according to a first embodiment of the present invention as viewed obliquely from the front.
As shown in FIG. 1, the machine tool 2 incorporating the thermal deformation prevention structure 1 according to the first embodiment of the present invention is installed in a building, and when viewed from the front, the structure 6 that supports the spindle 4 is provided. It is a machining center in the shape of a gate, and is also called a “gate-shaped machining center”. The machine tool 2 includes a bed 8 serving as a base. A guide groove 10 is formed on the upper surface of the bed 8 so as to extend in the front-rear direction. The table is movable along the guide groove 10 in the front-rear direction. 12 is provided.

The structure 6 is formed of cast iron or steel, and a column structure is a pair of hollow columnar structures that are part of the structure 6 and extend in the vertical direction on both sides of the bed 8 and the table 12. Body 14, 16 is provided.
Further, these column structures 14 and 16 are arranged with a space in the horizontal (left and right) direction of the machine tool 2, and above the inner surfaces of the column structures 14 and 16 facing each other, the structure A bridge structure 18 that is a part of the body 6 and extends in the horizontal (left-right) direction is provided so as to be bridged. A guide groove 20 extending in the left-right direction is provided in the upper region of the front surface of the bridge structure 18 and the front surfaces of the column structures 14, 16, and can be moved in the left-right direction of the machine tool 2 along the guide groove 20. A saddle member 22 is attached.

  Further, a feed screw 24 is provided in the guide groove 20 of the bridge structure 18 so as to extend in the longitudinal direction, and both ends of the feed screw 24 are supported by respective bearings 26 and 28 so as to be rotatable about the axis. ing. Further, one bearing 28 is provided with a motor 30 that rotates the feed screw 24 about its axis. When the motor 30 is driven, the feed screw 24 is driven to rotate, and the saddle member 22 is moved into the guide groove 20. It moves along the left-right direction of the machine tool 2 along.

  Further, the saddle member 22 is provided with a motor 32 for moving the main shaft 4 up and down and a motor 34 for rotating the main shaft 4 around the shaft. The vertical movement and the rotational movement of the tool 36 held at the lower end of 4 are adjusted.

  In addition, since each component of the machine tool 2 such as the feed screw 24, the bearings 26, 28, and the motors 30, 32, 34 described above generates heat when operated, the machine tool 2 It has become a heating element.

Next, the details of the thermal deformation prevention structure 1 according to the first embodiment of the present invention will be described with reference to FIGS.
First, FIG. 2 is a front sectional view showing the thermal deformation prevention structure according to the first embodiment of the present invention, and FIG. 3 shows the inner periphery of the column structure of the thermal deformation prevention structure according to the first embodiment of the present invention. It is the partial expansion perspective view which fractured partially and expanded so that a part could be seen.

  As shown in FIGS. 1 and 2, a liquid storage portion 40 that stores a liquid 38 is formed inside each column structure 14, 16 of the thermal deformation prevention structure 1 according to the first embodiment of the present invention. . As the liquid 38 accommodated in the liquid accommodating portion 40, water containing an additive having antiseptic and rust preventive properties is used, and the liquid 38 itself is prevented from being corroded and formed of cast iron or steel. Corrosion due to rust or the like of the liquid storage portion 40 of the column structures 14 and 16 can be prevented.

  Next, as shown in FIG. 2, the thermal deformation prevention structure 1 according to the present embodiment makes the temperature of the liquid 38 stored in the liquid storage unit 40 uniform over the entire liquid storage unit 40. A stirring means for stirring the liquid 38 in the liquid container 40 is used as a thermal deformation prevention means for reducing the temperature difference between the respective portions of the column structures 14 and 16 to prevent thermal deformation of the column structures 14 and 16. An impeller 42 is provided. The impeller 42 is arranged such that the rotating shaft 42b of the blade 42a extends in the vertical direction, and the central axis C1 of the rotating shaft 42b is substantially the same as the central axes A1 and A2 in the longitudinal direction of the column structures 14 and 16. They are arranged to match.

  Further, the opening 40a formed above the liquid container 40 is sealed by a lid 44 that is a sealing means, and can prevent the liquid 38 in the liquid container 40 from evaporating to the outside. The maintenance burden can be reduced. Further, the upper end portion of the rotating shaft 42 b penetrates the lid body 44 and is connected to a motor 44 provided at substantially the center of the upper surface of the lid body 44. By driving the motor 44, the rotating shaft 42b rotates and the impeller 42 rotates, so that the liquid 38 in the liquid storage unit 40 is constantly stirred.

  Next, as shown in FIG. 3, the thermal deformation prevention structure 1 according to the present embodiment moves the liquid 38 in the liquid storage unit 40 as thermal deformation prevention means for preventing thermal deformation of the column structures 14 and 16. A curved surface R, which is a heat transfer promoting means for promoting heat, is formed in an arc shape at the corner 40c of the inner peripheral surface 40b of the liquid container 40. As a result, as shown in FIG. 3 for an example of the flow of the liquid 38 in the liquid storage unit 40 that is being stirred by the impeller 42, the liquid 38 smoothly flows along the curved surface R of the inner peripheral surface 40b of the liquid storage unit 40. The stirring of the liquid 38 can be promoted. As a result, the temperature of the liquid 38 stored in the liquid storage unit 40 can be effectively made uniform over the entire liquid storage unit 40.

Next, the operation of the thermal deformation prevention structure 1 according to the first embodiment of the present invention described above will be described with reference to FIGS.
First, in the machine tool 2 in operation, each component of the machine tool 2 such as the feed screw 24, the bearings 26 and 28, and the motors 30, 32, 34, and 46 is changed into a heating element by each operation. Thus, the temperature around the machine tool 2 and the temperature of each part of the column structures 14 and 16 and the bridge structure 18 are affected.
However, on the other hand, in each column structure 14, 16, the blade 42a of the impeller 42 is always rotated by the thermal deformation prevention structure 1 according to the first embodiment of the present invention. The liquid 38 in the liquid container 40 is constantly stirred. The stirred liquid 38 moves smoothly along the curved surface R of the inner peripheral surface 40b of the liquid container 40, and the stirring of the liquid 38 is further promoted. Therefore, the liquid stored in the liquid container 40 The temperature of 38 is always made uniform over the entire liquid container 40.
As a result, it is possible to reduce the temperature difference between the respective parts of the structure 6 (particularly the column structures 14 and 16) due to the temperature change of the heating element of the machine tool 2 and the surroundings, and the structure 6 (particularly the column structure). The thermal deformation of the bodies 14, 16) can be effectively prevented. Therefore, high accuracy of the machine tool 2 can be realized.

  In addition, according to the thermal deformation prevention structure 1 according to the present embodiment, the opening 40 a above the liquid storage portion 40 of each column structure 14, 16 is sealed by the lid 44, so that the inside of the liquid storage portion 40 The liquid 38 can be prevented from evaporating to the outside, and the maintenance burden can be reduced.

  Furthermore, according to the thermal deformation prevention structure 1 according to the present embodiment, water containing an additive having antiseptic and rust preventive properties is used as the liquid 38 in the liquid storage portion 40 of each column structure 14, 16. Therefore, corrosion of the liquid 38 itself can be prevented, and corrosion due to rust or the like of the liquid storage portion 40 of the column structures 14 and 16 formed of cast iron or steel can be prevented. Therefore, the frequency of the exchange of the liquid 38 and the liquid container 40 due to corrosion is suppressed, and the parts of the structure 6 (particularly, the column structures 14 and 16) due to the temperature change of the heating element of the machine tool 2 and the surroundings. Therefore, it is possible to reliably reduce the temperature difference of the structure 6, effectively prevent thermal deformation of the structure 6 (particularly, the column structures 14, 16), and realize high accuracy of the machine tool 2.

  Further, according to the thermal deformation prevention structure 1 according to the present embodiment, the column structures 14 are formed so as to extend in the vertical direction and are arranged at intervals in the horizontal (left-right) direction of the machine tool 2 to form a pair. By providing the thermal deformation preventing structure 1 in each of the 16, it is possible to more effectively prevent the thermal deformation of the structural bodies 14 and 16 themselves, and realize high accuracy of the machine tool 2. Can do.

  In addition, in the thermal deformation prevention structure 1 of the present embodiment described above, the form applied to each of the column structures 14 and 16 of the portal machining center which is an example of the machine tool 2 has been described. The present invention is not limited to the portal machining center, and can be applied to other types of machine tools. That is, if the structure constituting the machine tool is a machine tool provided with a hollow columnar structure that easily undergoes thermal deformation such as bending deformation due to the temperature difference of each part, other types of machine tools Is also applicable. When the thermal deformation prevention structure of the present invention is applied to a machine tool other than the portal machining center, the hollow columnar structures may be a plurality of unpaired structures. However, it may be a single one.

Next, a thermal deformation prevention structure according to a second embodiment of the present invention will be described with reference to FIG.
FIG. 4 is a partially enlarged perspective view of the column structure of the thermal deformation preventing structure according to the second embodiment of the present invention, partially broken and enlarged so that the inner peripheral portion can be seen.
Here, regarding the structure of the machine tool in which the thermal deformation prevention structure 100 according to the second embodiment of the present invention is incorporated, the column structure of the machine tool 2 in which the thermal deformation prevention structure 1 according to the first embodiment of the present invention described above is incorporated. Since the structural parts other than the bodies 14 and 16 are the same, in FIG. 4, the same parts as those in the first embodiment of the present invention are denoted by the same reference numerals, description thereof is omitted, and only different structural parts are described. explain.

  As shown in FIG. 4, in the thermal deformation prevention structure 100 according to the second embodiment of the present invention, the liquid 38 in the liquid container 140 is used as a thermal deformation prevention means for preventing thermal deformation of the column structures 114 and 116. A spiral rib 148 that is a heat transfer promoting means for promoting the movement of the liquid container 140 protrudes inward from the inner peripheral surface 140b of the liquid container 140 and is formed in a spiral shape in the circumferential direction.

  According to the above-described thermal deformation prevention structure 100 according to the second embodiment of the present invention, the liquid 38 in the liquid storage unit 140 that is agitated by the rotation of the impeller 42 smoothly flows along the upper surface of the spiral rib 148. And the liquid 38 can be circulated in the vertical direction (the direction of the central axes A101 and A102 in the longitudinal direction of the column structures 114 and 116) in the liquid storage unit 140, so that the stirring of the liquid 38 is effectively promoted. Can do. Further, since the convection of the liquid 38 is effectively spread over the entire liquid storage part 140 of the column structures 114 and 116, the temperature of the liquid 38 stored in the liquid storage part 140 is more effectively uniformized. be able to. Therefore, while ensuring the strength and weight of the column structures 114 and 116, it is possible to more reliably reduce the temperature difference between the respective portions of the column structures 114 and 116 due to the heating element of the machine tool and the ambient temperature change. In addition, the thermal deformation of the column structures 114 and 116 can be more effectively prevented. Therefore, high accuracy of the machine tool can be realized.

Next, a thermal deformation prevention structure according to a third embodiment of the present invention will be described with reference to FIG.
FIG. 5 is a partially enlarged perspective view of the column structure of the thermal deformation preventing structure according to the third embodiment of the present invention, partially broken and enlarged so that the inner peripheral portion can be seen.
Here, regarding the structure of the machine tool in which the thermal deformation prevention structure 200 according to the third embodiment of the present invention is incorporated, the column structure of the machine tool 2 in which the above-described thermal deformation prevention structure 1 according to the first embodiment of the present invention is incorporated. Since the structural parts other than the bodies 14 and 16 are the same, in FIG. 5, the same parts as those in the first embodiment of the present invention are denoted by the same reference numerals, description thereof will be omitted, and only different structural parts will be described. explain.

  As shown in FIG. 5, in the thermal deformation prevention structure 200 according to the third embodiment of the present invention, the liquid 38 in the liquid storage unit 240 is used as a thermal deformation prevention means for preventing thermal deformation of the column structures 214 and 216. A plurality of vertical ribs 248, which are heat transfer promoting means for promoting heat exchange with the liquid, are formed so as to protrude inward from the inner peripheral surface 240b of the liquid storage portion 240 and extend in the longitudinal direction of the column structures 214, 216. ing.

  According to the above-described thermal deformation prevention structure 200 according to the third embodiment of the present invention, it is formed so as to protrude inward from the inner peripheral surface 240b of the liquid container 240 and to extend in the longitudinal direction of each column structure 214, 216. Since the surface area of the inner peripheral surface 240b of the liquid storage part 240 is increased by the plurality of vertical ribs 248 compared to the case where the vertical ribs 248 are not provided, the liquid storage part 240 being stirred by the rotation of the impeller 42. The amount of heat exchange between the liquid 38 and the vertical ribs 248 can be increased. Therefore, while ensuring the strength and weight of the column structures 214 and 216, it is possible to more reliably reduce the temperature difference between the portions of the column structures 214 and 216 due to changes in the temperature of the heating element and the surroundings of the machine tool. In addition, thermal deformation of the column structures 214 and 216 can be further effectively prevented. Therefore, high accuracy of the machine tool can be realized.

Next, a thermal deformation prevention structure according to a fourth embodiment of the present invention will be described with reference to FIG.
FIG. 6 is a front sectional view showing a thermal deformation prevention structure according to the fourth embodiment of the present invention.
Here, regarding the thermal deformation prevention structure 300 according to the fourth embodiment of the present invention, the liquid in the liquid storage portion 40 of each of the column structures 14 and 16 of the thermal deformation prevention structure 1 according to the first embodiment of the present invention described above. Since only the stirring means corresponding to the impeller 42 for stirring 38 is different, in FIG. 6, the same parts as those of the first embodiment of the present invention are denoted by the same reference numerals, and the description thereof is omitted. Only different structural parts will be described.

As shown in FIG. 6, in the thermal deformation prevention structure 300 according to the fourth embodiment of the present invention, the liquid container 40 is used as a stirring means for stirring the liquid 38 in the liquid container 40 of each column structure 14, 16. A pump device 350 for circulating the liquid 38 by pumping is provided.
The pump device 350 includes a pump device main body 352 provided on the lid 44 and incorporating a motor (not shown) and an impeller (not shown). The pump device main body 352 includes a liquid container. A suction pipe 354 is provided that extends to a position above the central portion in 40 and sucks the liquid 38. The pump device main body 352 is provided with a discharge pipe 356 that extends downward from the pump device main body 352 in parallel with the suction pipe 354, and the discharge port 356 a at the lower end of the discharge pipe 356 is formed at the bottom of the liquid storage unit 40. Located in the vicinity. The liquid 38 in the liquid container 40 is sucked into the pump device main body 352 from the suction port 354a of the suction pipe 354 by the operation of the pump device main body 352, and is then pumped to the discharge pipe 356, and the liquid is stored from the discharge port 356a. The ink is discharged into the portion 40. Thereby, the liquid 38 in the liquid container 40 circulates from below to above and is stirred throughout the liquid container 40.
In addition, about the internal peripheral surface 40b of the liquid storage part 40, you may provide the same thing as the curved surface R of 1st Embodiment mentioned above in the corner | angular part, or the helical rib 148 of 2nd Embodiment mentioned above. Alternatively, the vertical rib 248 of the third embodiment may be provided.

  According to the thermal deformation prevention structure 300 according to the above-described fourth embodiment of the present invention, the liquid 38 in the liquid storage portions 40 of the column structures 14 and 16 is effectively transferred by the pumping of the pump device 350 serving as the stirring means. Since it can stir, the temperature of the liquid 38 accommodated in the liquid accommodating part 40 can be equalized effectively over the liquid accommodating part 40 whole. Therefore, the temperature difference between the respective parts of the column structures 14 and 16 due to the heating element of the machine tool and the ambient temperature change can be surely reduced, and the thermal deformation of the column structures 14 and 16 is more effective. Can be prevented. Therefore, high accuracy of the machine tool can be realized.

Next, a thermal deformation prevention structure according to a fifth embodiment of the present invention will be described with reference to FIG.
FIG. 7 is a front sectional view showing a thermal deformation prevention structure according to a fifth embodiment of the present invention.
Here, regarding the thermal deformation prevention structure 400 according to the fifth embodiment of the present invention, the liquid in the liquid storage portion 40 of each of the column structures 14 and 16 of the thermal deformation prevention structure 1 according to the first embodiment of the present invention described above. The agitating means corresponding to the impeller 42 for agitating 38 is different and is different from the thermal deformation preventing structure 1 according to the first embodiment in that the lid body 44 as a sealing means is not provided. Therefore, in FIG. 7, the same parts as those in the first embodiment of the present invention are denoted by the same reference numerals, description thereof will be omitted, and only different structural parts will be described.

As shown in FIG. 7, in the thermal deformation prevention structure 400 according to the fifth embodiment of the present invention, an aeration apparatus 460 is used as a stirring means for stirring the liquid 38 in the liquid storage portion 40 of each column structure 14, 16. The liquid container 40 is provided at the bottom of the liquid container 40, and the opening 40a above the liquid container 40 is open to the atmosphere. Thereby, the aeration apparatus 460 supplies the air 462 to the liquid 38 in the liquid storage unit 40, and the air 462 can circulate the liquid 38 throughout the liquid storage unit 40.
In addition, about the internal peripheral surface 40b of the liquid storage part 40, you may provide the same thing as the curved surface R of 1st Embodiment mentioned above in the corner | angular part, or the helical rib 148 of 2nd Embodiment mentioned above. Alternatively, the vertical rib 248 of the third embodiment may be provided.

  According to the thermal deformation prevention structure 400 according to the fifth embodiment of the present invention described above, the aeration apparatus 460 serving as the agitation means supplies the air 462 to the liquid 38 in the liquid storage unit 40 and circulates it, so that each column structure. Since the liquid 38 in the liquid storage unit 40 of the bodies 14 and 16 can be effectively stirred, the temperature of the liquid 38 stored in the liquid storage unit 40 is effectively uniform over the entire liquid storage unit 40. Can be Therefore, the temperature difference between the respective parts of the column structures 14 and 16 due to the heating element of the machine tool and the ambient temperature change can be surely reduced, and the thermal deformation of the column structures 14 and 16 is more effective. Can be prevented. Therefore, high accuracy of the machine tool can be realized.

Next, a thermal deformation prevention structure according to a sixth embodiment of the present invention will be described with reference to FIG.
FIG. 8 is a front sectional view showing a thermal deformation prevention structure according to the sixth embodiment of the present invention.
As shown in FIG. 8, in the thermal deformation prevention structure 500 according to the sixth embodiment of the present invention, the thermal deformation according to the fifth embodiment of the present invention described above is that the liquid 538 in the liquid container 40 is oil. This is different from the liquid 38 in the liquid storage portion 40 of each column structure 14, 16 of the prevention structure 400.
Further, in the thermal deformation prevention structure 500 according to the sixth embodiment of the present invention, the oil cooler circulation device 560 that cools and circulates the liquid 538 that is the oil in the liquid storage unit 40 as the stirring means for stirring the liquid 538 is provided. This is different from the aeration apparatus 460 of the thermal deformation prevention structure 400 according to the fifth embodiment of the present invention described above.
Therefore, in FIG. 8, the same parts as those in the sixth embodiment of the present invention are denoted by the same reference numerals, description thereof will be omitted, and only different structural parts will be described.

As shown in FIG. 8, in the thermal deformation prevention structure 500 according to the sixth embodiment of the present invention, an oil cooler is used as means for stirring the liquid 538 that is oil in the liquid storage portion 40 of each column structure 14, 16. Circulation devices 560 are provided outside the column structures 14 and 16, respectively.
The oil cooler circulation device 560 is provided at the upper and lower portions of the liquid storage unit 40, respectively, and a suction pipe 562 and a discharge pipe 564, a heat radiating means 566 such as a heat radiating fin, an oil pump 568 and the like. It has. By operating the oil pump 568 of the apparatus main body 570, the liquid 538 in the liquid container 40 is supplied from the suction pipe 562 to the apparatus main body 562, and the liquid 538 is cooled by the heat radiation by the heat radiating means 562 of the apparatus main body 570. It has become so. Then, the cooled liquid 538 is supplied again from the discharge pipe 564 into the liquid storage unit 40, and the liquid 538 in the liquid storage unit 40 circulates from below to above, and extends throughout the liquid storage unit 40. It is designed to be stirred.
In addition, about the internal peripheral surface 40b of the liquid storage part 40, you may provide the same thing as the curved surface R of 1st Embodiment mentioned above in the corner | angular part, or the helical rib 148 of 2nd Embodiment mentioned above. Alternatively, the vertical rib 248 of the third embodiment may be provided.

  According to the thermal deformation prevention structure 500 according to the sixth embodiment of the present invention described above, the oil cooler circulation device 560 that is the stirring means cools and circulates the liquid 538 that is the oil in the liquid storage unit 40, thereby The liquid 538 in the liquid storage unit 40 of the column structures 14 and 16 can be effectively stirred, and the temperature of the liquid 538 stored in the liquid storage unit 40 can be effectively maintained over the entire liquid storage unit 40. Can be made uniform. Therefore, the temperature difference between the respective parts of the column structures 14 and 16 due to the heating element of the machine tool and the ambient temperature change can be surely reduced, and the thermal deformation of the column structures 14 and 16 is more effective. Can be prevented. Therefore, high accuracy of the machine tool can be realized.

DESCRIPTION OF SYMBOLS 1 Thermal deformation prevention structure 2 Machine tool 4 Spindle 6 Structure 8 Bed 10 Guide groove 12 Table 14 Column structure (1st structure)
16 Column structure (second structure)
18 Bridge structure 20 Guide groove 22 Saddle member 24 Feed screw (heating element)
26 Bearing (heating element)
28 Bearing (heating element)
30 Motor (heating element)
32 Motor (heating element)
34 Motor (heating element)
36 Tool 38 Liquid 40 Liquid storage part 40a Opening part 40b above liquid storage part 40b Inner peripheral surface of liquid storage part 40c Corner part of inner peripheral surface of liquid storage part 42 Impeller (stirring means)
42a Blade 42b Rotating shaft 44 Lid (sealing means)
46 Motor A1 Center axis in the longitudinal direction of the column structure A2 Center axis in the longitudinal direction of the column structure C1 Center axis of the rotating shaft of the impeller R Curved surface

Claims (12)

A thermal deformation prevention structure for a machine tool that prevents thermal deformation caused by a temperature change in the heating element of the machine tool or the surroundings,
A hollow columnar structure that is provided so as to extend in the vertical direction and constitutes a part of the machine tool;
A liquid container that is formed inside the structure and contains a liquid;
By equalizing the temperature of the liquid stored in the liquid storage section over the entire liquid storage section, the temperature difference between the portions of the structure body is reduced to prevent thermal deformation of the structure body. Thermal deformation preventing means,
The thermal deformation prevention means is provided on an inner peripheral surface of the liquid storage section and agitating means for stirring the liquid in the liquid storage section, and promotes movement of the liquid in the liquid storage section or heat exchange with the liquid. A structure for preventing thermal deformation of a machine tool, comprising: a heat transfer promoting means.   The structure for preventing thermal deformation of a machine tool according to claim 1, wherein the stirring means of the thermal deformation preventing means includes an impeller that is provided in the liquid storage portion and rotates to stir the liquid.   The thermal deformation prevention structure of a machine tool according to claim 1 or 2, wherein the heat transfer promotion means of the thermal deformation prevention means includes a curved surface that forms an angular portion of the inner peripheral surface of the liquid storage portion in an arc shape.   The heat transfer promoting means of the thermal deformation preventing means includes a spiral rib that protrudes inward from the inner peripheral surface of the liquid storage portion and is formed in a spiral shape along the circumferential direction. Structure for preventing thermal deformation of machine tools.   The heat transfer promoting means of the thermal deformation preventing means includes a plurality of vertical ribs formed so as to protrude inward from the inner peripheral surface of the liquid storage portion and extend in the longitudinal direction of the structure. The structure for preventing thermal deformation of the described machine tool.   2. The structure for preventing thermal deformation of a machine tool according to claim 1, wherein the stirring means of the thermal deformation preventing means includes a pump for circulating the liquid in the liquid container by pumping.   The structure for preventing thermal deformation of a machine tool according to any one of claims 2 to 6, wherein the liquid container is sealed by a sealing means.   2. The machine tool according to claim 1, wherein the stirring means of the thermal deformation preventing means includes an aeration device that circulates by supplying air to the liquid in the liquid storage portion, and the upper portion of the liquid storage portion is open to the atmosphere. Thermal deformation prevention structure.   The structure for preventing thermal deformation of a machine tool according to any one of claims 1 to 8, wherein the liquid in the liquid container is water containing an additive having antiseptic and antirust properties.   2. The machine tool according to claim 1, wherein the liquid in the liquid container is oil, and the stirring means of the thermal deformation prevention means includes an oil cooler circulation device that cools and circulates the oil in the liquid container. Thermal deformation prevention structure.   The structures are a first structure and a second structure that are formed so as to extend in the vertical direction and are arranged at intervals in the horizontal direction to form a pair. The first structure and the second structure 11. The structure for preventing thermal deformation of a machine tool according to claim 1, wherein each of the two structures is provided with the liquid storage portion and the thermal deformation preventing means.   A machine tool comprising the thermal deformation prevention structure according to any one of claims 1 to 11.

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