JP2011051027A - Connecting flange - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a connecting flange held between a motor and a frame to which the motor is mounted which prevents the transmission of heat from the motor to the frame in order to improve the rotational accuracy of a spindle to improve the accuracy of machining a workpiece by a machining tool. <P>SOLUTION: The connecting flange 10 is formed of a base element 10a in which a groove 11 is formed and a secondary element 10b fit on the base element 10a so as to cover the groove 11, thereby making a cooling fluid flow in the groove 11. The connecting flange 10 is then held between a flange 13 of the motor 1 and a mounting portion 19 of the frame 2 to prevent the transmission of heat from the motor 1 to the frame 2. <P>COPYRIGHT: (C)2011,JPO&amp;INPIT

Description

  The present invention relates to a connection flange used for connection between a frame that rotatably supports a spindle in a machine tool and a motor having a drive shaft that is connected to the spindle via a coupling. It is related with the connection flange which prevents that a flame | frame is transmitted to a flame | frame.

  In a machine tool such as a surface grinding machine, a spindle is mounted on a saddle that is mounted on a column that reciprocates in the Y-axis direction and reciprocates in the Z-axis direction while a workpiece is placed on a machining table that reciprocates in the X-axis direction. And a grindstone is attached to the tip of the spindle. Then, the workpiece on the processing table is ground by rotating the spindle and the grindstone. A frame is attached to the saddle, and a cylindrical quill is inserted and fixed to the frame. A spindle is supported inside the quill via a bearing. A drive shaft of a motor is connected to a base end portion of the spindle opposite to the side on which the grindstone is supported via a coupling.

  During the operation of the machine, the bearing generates heat as the spindle rotates at a high speed, and the heat is transmitted to the quill and further transmitted to the frame to raise the temperature of the frame. However, in general, in the spindle support structure as described above, the structures and masses of the upper and lower parts of the frame are different. Then, the amount of thermal expansion differs between the lower side portion and the upper side portion of the frame, and the frame slightly warps to one of the lower side portion and the upper side portion as a whole. For this reason, the quill and the spindle are slightly inclined with respect to a reference line (for example, a horizontal line). Since the rotation axis of the grindstone is decentered due to the inclination of the spindle, there is a problem in that the accuracy of the grinding surface of the workpiece is lowered.

  In the “support structure of spindle in machine tool” disclosed in Patent Document 1, a cylindrical quill is fitted and fixed to a frame, and the spindle is supported through a bearing inside the quill, and a grindstone is attached to the spindle. ing. A space allowing the cooling oil to flow is formed between the outer peripheral surface of the quill and the inner side surface of the frame. Cooling oil is supplied to this space from the outside, and the temperature of the quill and the frame is suppressed from rising due to the transmitted heat of the bearing. For this reason, non-uniform thermal expansion of the frame is suppressed, the spindle rotation accuracy can be improved, and the processing accuracy of the workpiece by the processing tool can be improved.

JP 2000-190150 A (see [Summary])

  In recent years, a very high level of machining accuracy is required in precision machining. According to the support structure of Patent Document 1, the cooling oil is supplied to the space between the quill and the frame to suppress the temperature rise of the quill and the frame. It is not designed to cool uniformly. In addition to the heat transmitted through the quill, there is heat transmitted from the motor through the mounting portion to increase the temperature of the frame. For this reason, the distortion of the entire frame is a problem that cannot be ignored as a support structure in precision machining that requires a high level of machining accuracy.

  The present invention has been made paying attention to such problems, and the object of the present invention is to attach a motor and a motor in order to increase the rotation accuracy of the spindle and improve the processing accuracy of the workpiece by the processing tool. Another object of the present invention is to provide a connecting flange that is sandwiched between a frame and a motor to prevent heat transfer from the motor to the frame.

  In order to solve the above-mentioned problem, the invention of the connecting flange according to claim 1 includes a frame that rotatably supports a spindle having a tool mounted on a tip thereof, and a drive shaft that is connected to the spindle via a coupling. In connection with the motor, the flow path is formed between the mounting portion of the frame and the flange portion of the motor, and allows passage of the cooling fluid.

  According to the above configuration, the heat transferred from the flange portion of the motor is taken away by the cooling fluid flowing through the flow path. For this reason, since heat transfer from the flange portion of the motor to the frame is prevented, the heat for raising the temperature of the frame can be limited to the heat of the bearing transmitted through the quill or the like. Therefore, it becomes easy to adjust the temperature of the frame in order to prevent the occurrence of distortion due to thermal expansion.

  According to a second aspect of the present invention, in the connecting flange according to the first aspect, the flow path is a groove formed in a flat portion arranged in a direction orthogonal to the drive shaft. It is.

  According to the said structure, the groove | channel was formed in the plane part arrange | positioned in the direction orthogonal to the drive shaft of a motor, and the groove | channel was made into the flow path. For this reason, unlike the case of forming a flow path by drilling holes from a plurality of locations at the end of the connection flange and crossing a part of each hole, a flow path of any shape can be easily formed. Can be formed.

  The invention according to claim 3 is the connecting flange according to claim 2, wherein the flow path is a plurality of linear or curved grooves connected by a plurality of bending points or inflection points in the plane portion. It is characterized by being.

  According to the above configuration, a plurality of linear or curved grooves are connected by a plurality of bending points or inflection points to make the flow path longer. For this reason, since the area where the cooling fluid contacts the connection flange increases until the cooling fluid is supplied to the connection flange and discharged, the cooling fluid can take more heat transferred from the motor.

  According to a fourth aspect of the present invention, there is provided the connecting flange according to the second or third aspect, wherein the flow path is arranged in a meandering manner in which the position of the flow path is alternately changed between an inner side and an outer side of a reference circle. It is characterized by being.

  According to the said structure, the groove | channel as a flow path was arrange | positioned in the meandering form which changes a position alternately to the inner side and the outer side of a reference | standard circle. For this reason, since the flow path covers a wide range and the cooling fluid can flow smoothly through the flow path, the connection flange can be efficiently cooled.

  A fifth aspect of the present invention is the connecting flange according to any one of the second to fourth aspects, wherein the groove is continuously formed in a single stroke by an end mill. is there.

  According to the said structure, the groove | channel was continuously formed in the stroke shape using the end mill. For this reason, it is possible to prevent the formation of a portion where the cooling fluid stops in the middle of the flow path. Therefore, the temperature-controlled cooling fluid can be efficiently used for cooling the connecting flange. Moreover, as a damming stop, for example, a troublesome operation such as driving a boss can be omitted so that the cooling fluid does not flow into the dead end portion.

  According to a sixth aspect of the present invention, in the connecting flange according to any one of the second to fifth aspects, the base body in which the groove is formed on one plate-like surface and the sub-body that covers the one surface of the base body It is characterized by comprising.

  According to the said structure, the connection flange which has a flow path inside was formed by the base | substrate and the subbody which covers the surface in which the groove | channel of the base | substrate was formed. For this reason, the liquid sealant is applied to the flange portion or the attachment portion as in the case where the flow path is formed by combining the grooved surface of the base with the flange portion of the motor or the attachment portion of the frame. Therefore, it is possible to omit finishing processing for increasing the surface roughness and groove processing for arranging a sealing material such as a gasket.

  According to the present invention, the heat transferred from the flange portion of the motor is taken away by the cooling fluid flowing through the flow path of the connecting flange. For this reason, heat transfer from the motor flange to the frame is prevented, so the heat that raises the temperature of the frame can be limited to the heat of the bearing transmitted through the quill, and the temperature control of the frame Easy to do. Therefore, the rotational accuracy of the spindle can be increased, and the processing accuracy of the workpiece by the processing tool can be improved.

Sectional drawing which shows the aspect by which the connection flange of 1st Embodiment was clamped between the motor and the flame | frame. AA arrow sectional drawing in FIG. B arrow view in FIG. The AA arrow sectional drawing in FIG. The AA arrow directional cross-sectional view in FIG. Sectional drawing which shows the aspect by which the connection flange of 2nd Embodiment was clamped between the motor and the flame | frame.

(First embodiment)
Hereinafter, a first embodiment embodying the present invention will be described with reference to FIGS. 1 to 3, and another example will be described with reference to FIGS. 4 and 5.

  First, the arrangement and part of the structure of the frame 2 and the motor 1 that sandwich the connecting flange 10 of the present embodiment will be described. As shown in FIG. 1, a cylindrical quill 4 is fitted and fixed to a frame 2 attached to a saddle (not shown) supported so as to be reciprocable in the Z-axis direction. Inside the quill 4, the spindle 3 is rotatably supported by a radial bearing 5 and a thrust bearing 6. The thrust bearing 6 is supported by a holder 7 fixed to the quill 4 by a bolt (not shown). The spindle 3 and the drive shaft 9 of the motor 1 are connected by a coupling 8.

  The flange portion 13 of the motor 1 having the drive shaft 9 is formed with an annular convex portion 14 concentric with the axis of the drive shaft 9, and the convex portion 14 includes a base body 10 a and a sub body 10 b constituting the connecting flange 10. Are fitted into the recess 15 of one of the substrates 10a. Further, an annular convex portion 16 concentric with the concave portion 15 is formed on the surface of the base 10 a opposite to the surface on which the concave portion 15 is formed, and is fitted into the concave portion 17 of the frame 2. Further, the sub body 10b is arranged so as to face the attachment portion 19 of the frame 2. The sub-body 10 b has a central hole that is fitted around the convex portion 16.

  The connecting flange 10 is sandwiched between the mounting portion 19 and the flange portion 13 by a bolt (not shown) that is screwed into a screw hole (not shown) formed in the mounting portion 19. At this time, the groove 11 having a square cross section formed in the base body 10a is covered with the sub body 10b to form a channel having a shape described later. The material of the base body 10a and the sub body 10b is not particularly limited, but it is preferable to use a metal having excellent heat conductivity, such as an aluminum alloy, bronze, brass, or the like for both or any one of them.

  A sealing material such as a liquid sealant or a gasket is provided between the base body 10a and the sub body 10b so that the cooling fluid flowing through the groove 11 does not leak. In the present embodiment, a gasket groove (not shown) is provided on the surface of the secondary body 10b facing the base body 10a so as to correspond to the seal position 24 indicated by the two-dot chain line in FIG. Yes. Further, a gasket (not shown) is also attached to the convex portion 16 of the base body 10a.

  As shown in FIG. 2, the base body 10a is a square plate-like body, and bolt holes 27 are formed at four corners. Although not shown, the outer shape of the sub body 10b is also the same as that of the base body 10a, and the bolt holes 27 having the same arrangement are formed.

  The groove 11 serving as a cooling fluid flow path is a meandering curved groove 11a that changes in a meandering manner alternately between the inside and the outside of the reference circle 23 that is concentric with the drive shaft 9. An outwardly convex curved groove 11b is formed at an inflection point 11c. Thus, in order to form the groove 11 in a single stroke, processing by an end mill is preferable, and further, end mill processing by NC is preferable.

  In addition, the magnitude | size of the reference | standard circle 23 is not specifically limited, It can be made arbitrary. In this embodiment, the inflection point 11c is substantially on the reference circle 23. However, the inflection point 11c can be arranged inside or outside the reference circle 23. Furthermore, in the present embodiment, the number of the curved grooves 11b is 7, but it may be 6 or less or 8 or more. From the viewpoint of cooling efficiency by the cooling fluid, it is preferable to select the size of the reference circle 23, the position of the inflection point 11c, the number of curved grooves 11b, and the like.

  As shown in FIGS. 2 and 3, a supply connection portion 21 and a discharge connection portion 22 that are connected by a pipe to a temperature adjusting portion for a cooling fluid (not shown) are provided on the side surface of the base body 10 a. The cooling fluid is supplied to the groove 11 through a communication hole 26 formed in the supply connection portion 21 and a communication hole 25 formed in a direction orthogonal to the communication hole 26. And the cooling fluid which distribute | circulated the groove | channel 11 via the communicating hole 26 formed in the discharge | emission connection part 22 and the communicating hole 25 formed in the direction orthogonal to the communicating hole 26 is a cooling fluid. Is returned to the temperature control section. In this embodiment, oil is used as the cooling fluid, but other cooling liquids such as water or coolant may be used.

  As described above, when the cooling fluid flows through the groove 11 of the connecting flange 10, the heat transmitted from the flange portion 13 of the motor 1 is not transmitted to the mounting portion 19 of the frame 2, but is transferred to the cooling fluid. Stolen. Further, when the temperature of the frame 2 rises, the heat of the frame 2 is taken away by the cooling fluid through the attachment portion 19. Therefore, the temperature of the frame 2 can be easily adjusted.

Next, alternative examples 1 and 2 of the base body 10a having flow paths different from the arrangement of the grooves 11 shown in FIG. 2 will be described with reference to FIGS.
As shown in FIG. 4, in the base body 10 a of Example 1, a groove 30 as a flow path connects the large diameter portion 31 and the small diameter portion 32 at four locations, and the large diameter portion 31 and the small diameter portion 32. It consists of seven radial parts 33. The large-diameter portion 31 and the small-diameter portion 32 are arcs concentric with the axis of the drive shaft 9, and the radial portion 33 faces the radial direction of the arc. A portion where the large diameter portion 31 or the small diameter portion 32 and the radial portion 33 are connected serves as a bending point 34 that changes the direction of the groove 30. Thus, the groove | channel 30 which has the some bending point 34 can lengthen a flow path compared with the groove | channel 11 which has the inflection point 11c. That is, the area where the cooling fluid contacts the base body 10a can be increased.

  In addition, although each of the large diameter part 31 and the small diameter part 32 was provided in four places, it can provide in arbitrary multiple places not only in four places. If the number is large, the number of the bending points 34 increases accordingly, and the length of the groove 30 becomes longer, so that the cooling effect is enhanced.

  As shown in FIG. 5, in the base body 10 a of another example 2, the groove 40 as the flow path is an outer circle portion 41, a middle circle portion 42, and an inner circle portion 43 that are arcs concentric with the axis of the drive shaft 9. And a radial portion 45 and a radial portion 46 that are connected to each other at a bending point 34. The end of the inner circle portion 43 and the communication hole 25 are connected by a radial portion 47. Although the grooves 40 arranged in this way can be obtained as a relatively long flow path, it is possible to save labor in inputting numerical values for end mill processing by the NC.

  In addition, although the circular arc part of the groove | channel 40 was comprised by the three outer circle parts 41 from which a radius differs, the middle circle part 42, and the inner circle part 43, the number of circular arcs is not restricted to this, The width | variety of the groove | channel 40 is adjusted. For example, it may be 2 or less or 4 or more.

Therefore, according to the above embodiment, the following effects can be obtained.
(1) In the above embodiment, the cooling fluid flowing through the groove 11 serving as the flow path takes away the heat transmitted from the flange portion 13 of the motor 1 to the connection flange 10. For this reason, since heat transfer from the flange portion 13 of the motor 1 to the frame 2 is blocked, heat for increasing the temperature of the frame 2 is transmitted to the radial bearing 5 and the thrust bearing 6 via the quill 4 or the like. It can be limited to. Accordingly, the temperature of the frame 2 can be easily adjusted, and the occurrence of distortion due to thermal expansion can be prevented. Therefore, the rotation accuracy of the spindle can be increased and the processing accuracy of the workpiece by the processing tool can be improved.

  (2) In the above-described embodiment, the grooves 11, 30, and 4 are formed on the surface opposite to the surface facing the flange portion 13 of the base body 10 a, which is a plane portion arranged in a direction orthogonal to the drive shaft 9 of the motor 1. 40 was formed, and the grooves 11, 30, and 40 were used as flow paths. For this reason, unlike the case of forming a flow path by drilling holes from a plurality of locations on the outer periphery of the connecting flange, and forming a flow path so that a part of each hole intersects, a flow path of an arbitrary shape is used as an end mill, etc. Can be easily formed.

  (3) In the above embodiment, the grooves 11 as the flow paths are arranged in a meandering manner in which the positions are alternately changed between the inside and the outside of the reference circle 23. For this reason, since the flow path covers a wide range and the cooling fluid can flow smoothly through the flow path, the connection flange 10 can be efficiently cooled.

  (4) In the above embodiment, the plurality of large-diameter portions 31 and the small-diameter portions 32 are connected by the radial portions 33 at the bending points 34 to form the grooves 30 as longer flow paths. For this reason, since the area where the cooling fluid contacts the connecting flange 10 before being supplied to the connecting flange 10 and discharged is increased, the cooling fluid can take more heat transferred from the motor 1. it can.

  (5) In the above embodiment, the outer circle portion 41, the middle circle portion 42 and the inner circle portion 43 are connected by the radial portions 45 and 46 at a plurality of bending points 34 to form the groove 40 as a longer flow path. did. For this reason, the cooling fluid can efficiently take away the heat transmitted from the motor, and it is possible to save the input of numerical values for end milling the groove 40 by the NC.

  (6) In the above embodiment, the grooves 11, 30, and 40 are continuously formed in a single stroke using an end mill. For this reason, it is possible to prevent the formation of a portion where the cooling fluid stops in the middle of the flow path. Therefore, the temperature-controlled cooling fluid can be efficiently used for cooling the connecting flange 10. Moreover, as a damming stop, for example, a troublesome operation such as driving a boss can be omitted so that the cooling fluid does not flow into the dead end portion.

  (7) In the above embodiment, the connecting flange 10 having a flow path is formed by the base body 10a and the sub body 10b covering the surface of the base body 10a where the grooves 11, 30, 40 are formed. For this reason, as in the case where the flow path is formed by combining the surface of the base body 10a where the grooves 11, 30, 40 are formed and the flange portion 13 of the motor 1 or the mounting portion 19 of the frame 2, the flange portion 13 or In the mounting portion 19, it is possible to omit a finishing process for increasing the surface roughness due to the use of the liquid sealant and a groove process for arranging a sealing material such as a gasket.

(Second Embodiment)
Next, a second embodiment embodying the present invention will be described with reference to FIG. 6 with a focus on differences from the first embodiment. Note that this embodiment is the same as the first embodiment except that the sub-body 10b is not used, and the other parts are the same in configuration. Therefore, the description of the different parts is omitted and the description of the other parts is omitted. .

  As shown in FIG. 6, the surface of the connecting flange 50 where the groove 11 is formed is directly aligned with the mounting portion 19 of the frame 2. Further, the connecting flange 50 is formed with a convex part 51 concentric with the axis of the drive shaft 9, and the convex part 51 is fitted in the concave part 17 of the frame 2.

  Thus, in order to bring the connecting flange 50 and the mounting portion 19 into contact with each other and to make the groove 11 a flow path for the cooling fluid, in a position corresponding to the seal position 24 shown by the two-dot chain line in FIG. The mounting portion 19 is provided with a gasket groove (not shown).

  In the present embodiment, the groove 11 is formed on the surface of the connecting flange 50 that faces the mounting portion 19, but the groove 11 can also be formed on the surface of the connecting flange 50 that faces the flange portion 13. At this time, in order to use a sealing material such as a gasket, a groove for the sealing material needs to be formed on either surface of the connecting flange 50 or the flange portion 13. When a liquid sealing agent is used, the formation of grooves can be omitted. In addition, instead of the groove 11 shown in FIG. 2, the groove 30 shown in FIG. 4 or the groove 40 shown in FIG.

And in this 2nd Embodiment, in addition to the effect in 1st Embodiment, the following effects can be acquired.
(8) In the said embodiment, the connection flange 50 and the attaching part 19 were contacted, and the groove | channels 11, 30, and 40 were used as the flow path for the cooling fluid. For this reason, the number of parts could be reduced.

(Example of change)
In addition, the said embodiment can also be changed and actualized as follows.
The grooves 11, 30, and 40 are formed in the base body 10a by an end mill, but the grooves 11, 30, and 40 are formed by a mold so that the base body 10a is manufactured by die casting.
2, 4 and 5, the supply connecting portion 21 and the discharge connecting portion 22 are arranged up and down, but the arrangement of the grooves 11, 30 and 40 is left as it is, the discharge connecting portion 22 is set upward and the supply connecting portion 21 is set downward. To place in.
-Although the inner shape is square at the bending point 34 of the grooves 30, 40, it should be arcuate.

  DESCRIPTION OF SYMBOLS 1 ... Motor, 2 ... Frame, 3 ... Spindle, 8 ... Coupling, 9 ... Drive shaft, 10a ... Base | substrate, 10b ... Sub-body, 11, 30, 40 ... Groove, 11c ... Inflection point, 13 ... Flange part, 19 ... Mounting part, 23 ... Reference circle, 34 ... Bending point.

Claims (6)

  In a connection between a frame that rotatably supports a spindle with a tool mounted on the tip and a motor having a drive shaft that is connected to the spindle via a coupling, an attachment portion of the frame, a flange portion of the motor, A connection flange, characterized in that a flow path is formed between the two and allowing passage of a cooling fluid.   The connection flange according to claim 1, wherein the flow path is a groove formed in a flat portion disposed in a direction orthogonal to the drive shaft.   The connection flange according to claim 2, wherein the flow path is a plurality of linear or curved grooves connected by a plurality of bending points or inflection points in the plane portion.   4. The connecting flange according to claim 2, wherein the flow path is a groove arranged in a meandering manner whose position is alternately changed between an inner side and an outer side of a reference circle in the plane portion.   The connecting flange according to any one of claims 2 to 4, wherein the groove is continuously formed in a single stroke by an end mill.   The connecting flange according to any one of claims 2 to 5, comprising a base body having the groove formed on a plate-like surface and a sub-body that covers the one surface of the base body.

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