Cooling and load compensation device for ram spindle and machine tool including such device

Abstract

This invention relates to a cooling and load compensation device for a ram spindle and a machine tool including the device. When thermal deformation occurs on the ram spindle, which is moved by a box-shaped guide rail, a cooling unit cools the friction part between the ram spindle and the saddle. When the load on the clamping bars changes due to the thermal deformation of the ram spindle caused by the cooling unit, multiple clamping bars are respectively arranged between the saddle and the ram spindle, corresponding to the reference surface in the horizontal or vertical direction, except for the reference surface that is in close contact with the inner side of the saddle and the ram spindle. At this time, the load occurring on the clamping bars is automatically compensated by a hydraulic closed loop to maintain a constant surface pressure acting on the clamping bars. This improves the machining accuracy of the machine tool, prevents resource waste and saves machining costs, increases productivity with the increase of non-machining time, and improves the stability and reliability of the machine tool.

Description

Technical Field

[0001] This invention relates to a cooling and load compensation device for a ram spindle and a machine tool including the device. More specifically, it relates to a cooling and load compensation device for a ram spindle and a machine tool including the device. When thermal deformation occurs on the ram spindle, which is moved in a box-shaped guide rail manner, a cooling unit cools the friction part between the ram spindle and the saddle. When the load on the clamping bar changes due to the thermal deformation of the ram spindle, the load generated on the clamping bar is automatically compensated to automatically and constantly maintain a predetermined pressure acting on the clamping bar, thereby improving the machining accuracy of the machine tool. Background Technology

[0002] Generally speaking, a machine tool is a machine used to process metal / non-metal workpieces into the required shape and size by means of appropriate tools through various cutting or non-cutting methods.

[0003] Machine tools such as turning centers, vertical / horizontal machining centers, gantry machining centers, switch machines, electrical discharge machining centers, horizontal NC drilling machines, CNC lathes, and multi-functional machining centers are widely used in various industrial settings according to their respective applications.

[0004] A multi-functional machining center in machine tools refers to a turning center equipped with a tool magazine, which performs various machining operations such as turning, drilling, tapping, and milling. In a multi-functional machining center, the operator manually loads the tools into the tool magazine when loading or exchanging the tools required for machining.

[0005] Generally, many machine tools currently in use have a control console that utilizes numerical control (NC) or CNC (computerized numerical control) technology. This control console has various function switches or buttons and a monitor.

[0006] In addition, the machine tool includes: a transfer table for placing workpieces or materials and transferring workpieces for processing; a tray for preparing workpieces before processing; a spindle that rotates in conjunction with a tool or workpiece; a tailstock for supporting the workpiece during processing; and shockproof devices, etc.

[0007] Generally, machine tools include transfer units such as transfer tables, tool tables, spindles, tailstocks, and anti-vibration devices, which are moved along the transfer axis to perform various machining operations.

[0008] In addition, machine tools typically use multiple tools to perform various machining operations, and tool magazines or turrets are used to house and store these multiple tools.

[0009] In order to perform various processes, machine tools use multiple tools, and a tool library is used to store and store these multiple tools.

[0010] Generally, in order to improve the productivity of machine tools, machine tools are equipped with an automatic tool changer (ATC). The automatic tool changer retrieves or re-accompanies a specific tool from the tool magazine through commands from the CNC unit.

[0011] In addition, to minimize non-machining time, machine tools are generally equipped with an Automatic Palette Changer (APC). The APC automatically exchanges pallets between the workpiece machining area and the workpiece setting area. Workpieces can be loaded onto the pallets.

[0012] Generally speaking, a machining center is a machine tool equipped with an automatic tool changer, which allows for the replacement of various types of tools and enables it to perform a wide range of machining operations on lathes, milling machines, drilling machines, boring machines, etc. It is broadly classified into vertical machining centers with vertically mounted spindles and horizontal machining centers.

[0013] Generally, a double column type machine center is a type of large machine tool. Unlike lathes, which perform simple machining, it refers to a device that directly processes three-dimensional shapes by exchanging multiple head attachments.

[0014] The gantry machining center can detachably mount various head attachments at the lower end of the ram spindle to process workpieces of various shapes in various spaces and angles.

[0015] Thus, the existing machine tool uses a box guideway to move the ram spindle relative to the saddle in the height direction.

[0016] When using this box-type guideway method to move the ram spindle relative to the saddle, a large amount of heat is generated due to the larger contact area and greater friction compared to the linear motor guideway method. In particular, with the box-type guideway method, a large amount of heat is generated on the contact friction surface between the outer corner of the ram spindle and the saddle, causing displacement of the ram spindle in the height direction (Z-axis direction) and vertical direction (X-axis direction), thus reducing the machining accuracy of the machine tool.

[0017] That is, such as Figure 1As shown, in machine tools that use box-type guideways to transfer the ram spindle relative to the saddle, when the saddle moves linearly back and forth along the crossbeam in the horizontal direction (Y-axis direction), thermal expansion caused by heat leads to deformation. Therefore, when displacement occurs in the vertical direction (X-axis direction), machining accuracy decreases, and problems such as workpiece waste and increased machining costs due to machining defects occur. Specifically, when the saddle repeatedly moves from 600mm to 2600mm in the horizontal direction (Y-axis direction) along the crossbeam using box-type guideways, it is known that thermal expansion caused by heat results in deformation of up to 125μm in the vertical direction (X-axis direction), which leads to a decrease in machining accuracy.

[0018] In existing machine tools that use box-type guideways to move the ram spindle, when the ram spindle deforms due to heat generated at the contact friction surface between the ram spindle and the saddle, the correction is performed by adjusting the position of the tool installed at the front end of the ram spindle.

[0019] However, existing cooling and load compensation devices for ram spindles that use box-type guideways to transfer the ram spindle, as well as machine tools that include such devices, still have the problem of possible calibration errors due to changes in ambient temperature or the reliability of sensors. Since the heat source itself cannot be controlled, only thermal deformation caused by local expansion due to frictional heat can be corrected. Due to this limitation, the machining accuracy of the machine tool still decreases and its reliability is reduced.

[0020] In addition, existing cooling and load compensation devices for ram spindles that use box-type guide rails to transfer the ram spindle, as well as machine tools that include such devices, have the problem that although negative control is implemented considering the heat generated when the spindle rotates and the season or surrounding environment, condensation caused by the season or surrounding environment can lead to short circuits or rusting of the ram spindle motor, thus increasing the possibility of equipment damage or destruction and accidents.

[0021] Furthermore, existing cooling and load compensation devices for ram spindles that use box-shaped guide rails to transfer the ram spindle, as well as machine tools that include such devices, require cooling of the ram spindle due to thermal deformation that occurs during the transfer and operation of the ram spindle, and need to maintain constant surface pressure due to the load acting on the clamping bars. This requires various software or hardware, resulting in complex structures, increased manufacturing costs, and a significant amount of installation time, causing inconvenience to workers.

[0022] In addition, existing cooling and load compensation devices for ram spindles that use box-type guide rails to transfer ram spindles, as well as machine tools that include such devices, suffer from reduced stability and reliability due to decreased machining accuracy, increased maintenance costs and time, and decreased machine tool productivity due to increased non-machining time. Summary of the Invention

[0023] Technical issues

[0024] This invention addresses the aforementioned problems. One objective is to provide a cooling and load compensation device for a ram spindle and a machine tool including this device. When the ram spindle, transported via a box-type guideway, undergoes thermal deformation, a cooling unit cools the friction portion between the ram spindle and the saddle. When the load on the clamping bars changes due to the thermal deformation of the ram spindle, multiple clamping bars are arranged between the saddle and the ram spindle, corresponding to the reference surface in either the horizontal or vertical direction, except for the reference surface on the inner side of the saddle that is in close contact with the ram spindle. The load on the clamping bars is automatically compensated by a hydraulic closed-loop system to maintain a constant surface pressure on the clamping bars. This improves the machining accuracy of the machine tool, prevents resource waste, saves machining costs, increases productivity with increased non-machining time, and enhances the stability and reliability of the machine tool.

[0025] Technical solution

[0026] To achieve the objectives of this invention, a cooling and load compensation device for a ram spindle according to the present invention includes: a saddle configured to be movable along a crossbeam; a ram spindle configured to be movable along the saddle; a conveying unit for conveying the ram spindle to the saddle via a box-shaped guide rail; a cooling unit for cooling the ram spindle; and a load compensation unit having clamps for adjusting the load applied from the ram spindle to the saddle, wherein multiple clamps are provided between the saddle and the ram spindle, except for a reference surface on the inner side of the saddle that is in close contact with the ram spindle, and are respectively corresponding to the reference surface in the horizontal or vertical direction.

[0027] Furthermore, in another preferred embodiment of the cooling and load compensation device for the slide spindle according to the present invention, when the slide spindle of the cooling and load compensation device for the slide spindle undergoes thermal deformation, the cooling unit cools the slide spindle. When the load on the clamp changes due to the thermal deformation of the slide spindle, the load compensation unit automatically compensates for the load occurring on the clamp, thereby automatically and constantly maintaining the surface pressure acting on the clamp.

[0028] Furthermore, in another preferred embodiment of the cooling and load compensation device for the ram spindle according to the present invention, the transfer unit of the cooling and load compensation device for the ram spindle includes a drive unit for generating power to transfer the ram spindle, and the reference surface may be formed in a plurality of surfaces that are in close contact with a portion of the inner side of the saddle adjacent to the drive unit and a portion of the outer side corner of the ram spindle.

[0029] Furthermore, in another preferred embodiment of the cooling and load compensation device for the ram spindle according to the present invention, the clamping bar of the cooling and load compensation device for the ram spindle can be respectively inserted between the inner portion of the saddle opposite to each of the reference surfaces centered on the plurality of reference surfaces and the portion adjacent to the outer corner of the ram spindle.

[0030] Furthermore, in another preferred embodiment of the cooling and load compensation device for the ram spindle according to the present invention, the clamping bars of the cooling and load compensation device for the ram spindle may each include: a main body having a horizontal portion formed parallel to the height direction on one side and a tapered portion that gradually tapers along the height direction on the other side and contacts the saddle; a recessed portion formed in a portion of the tapered portion to accommodate hydraulic pressure; and a sealing portion for preventing hydraulic pressure leakage from the recessed portion.

[0031] Furthermore, in a preferred embodiment of the cooling and load compensation device for the ram spindle according to the present invention, the load compensation unit of the cooling and load compensation device for the ram spindle may include: a hydraulic flow path formed to pass through a portion of the saddle, such that one side is connected to the recess; and a compensation section provided in communication with the other side of the hydraulic flow path, which recovers hydraulic pressure from the recess or supplies hydraulic pressure to the recess according to the load generated on the clamping bar.

[0032] Furthermore, in another preferred embodiment of the cooling and load compensation device for the ram spindle according to the present invention, the compensation part of the cooling and load compensation device for the ram spindle may include a storage part, which is expandably disposed inside the compensation part for storing hydraulic fluid.

[0033] Furthermore, in another preferred embodiment of the cooling and load compensation device for the ram spindle according to the present invention, four clamps of the cooling and load compensation device for the ram spindle may be provided between the upper and lower portions of the inner portion of the saddle opposite each of the reference surfaces and the portion adjacent to the outer corner of the ram spindle.

[0034] Furthermore, in another preferred embodiment of the cooling and load compensation device for the ram spindle according to the present invention, the cooling unit of the cooling and load compensation device for the ram spindle may include: a plurality of cooling flow paths extending through a portion of the ram spindle in the height direction or inserted into a portion of the ram spindle for cooling fluid flow; and a connecting portion disposed in communication with each of the cooling flow paths in a portion of the ram spindle to transfer cooling fluid to each of the cooling flow paths or to recover or circulate the cooling fluid.

[0035] Furthermore, in another preferred embodiment of the cooling and load compensation device for the ram spindle according to the present invention, the plurality of cooling flow paths of the cooling and load compensation device for the ram spindle can be arranged in four adjacent to the inner corner of the ram spindle adjacent to the contact friction surfaces of the ram spindle and the saddle.

[0036] Furthermore, in another preferred embodiment of the cooling and load compensation device for the ram spindle according to the present invention, the cooling unit of the cooling and load compensation device for the ram spindle may further include: a sensing part disposed on the ram spindle for sensing the temperature of the ram spindle; and a sealing part disposed inside each of the joints to prevent cooling fluid from leaking from the cooling flow path.

[0037] Furthermore, in another preferred embodiment of the cooling and load compensation device for the ram spindle according to the present invention, the cooling unit of the cooling and load compensation device for the ram spindle may further include a support portion disposed at the upper and lower parts of each cooling flow path to support the cooling flow path.

[0038] To achieve another objective of the present invention, a machine tool including a cooling and load compensation device for a ram spindle according to the present invention may include: a bed; a pair of columns extending along the height direction on both sides of the bed; a crossbeam configured to be movable along the pair of columns; a saddle configured to be movable along the crossbeam; a ram spindle configured to be movable along the saddle; and a cooling and load compensation device for the ram spindle, which cools the ram spindle and compensates for the load when the ram spindle thermally expands. The cooling and load compensation device for the ram spindle may include: a transfer unit having a drive unit that guides the saddle via a box-shaped guide rail. The system includes: a method for transferring the ram spindle; a cooling unit for cooling the ram spindle; and a load compensation unit. Multiple clamping bars are provided between the saddle and the ram spindle, except for the reference surface on the inner side of the saddle that is in close contact with the ram spindle, corresponding to the reference surface in the horizontal or vertical direction. The system automatically compensates for the load applied to the saddle from the ram spindle. When the ram spindle undergoes thermal deformation, the cooling unit cools the ram spindle. As the load applied to the clamping bars changes due to the thermal deformation of the ram spindle, the system automatically compensates for the load to maintain a constant surface pressure on the clamping bars.

[0039] Furthermore, in another preferred embodiment of a machine tool including a cooling and load compensation device for a ram spindle according to the present invention, the reference surface of the machine tool including the cooling and load compensation device for a ram spindle can be formed in multiple ways. These surfaces are the inner part of the saddle adjacent to the drive unit and the part adjacent to the outer corner of the ram spindle. The clamping bars can be provided with four clamping bars centered on the multiple reference surfaces, between the upper and lower parts of the inner part of the saddle and the part adjacent to the outer corner of the ram spindle, respectively, with reference to the diagonal line passing through the non-adjacent corners of the ram spindle.

[0040] Invention Effects

[0041] The cooling and load compensation device for the ram spindle according to the present invention, and the machine tool including the device, have the following effects: when the ram spindle, which is moved by a box-shaped guide rail, undergoes thermal deformation, the friction part between the ram spindle and the saddle is cooled by the cooling unit. When the load on the clamping bars changes due to the thermal deformation of the ram spindle, multiple clamping bars are arranged between the saddle and the ram spindle, except for the reference surface that is in close contact with the inner side of the saddle and the ram spindle, corresponding to the reference surface in the horizontal or vertical direction. At this time, the load occurring on the clamping bars is automatically compensated by a hydraulic closed loop to maintain a constant surface pressure acting on the clamping bars. Thus, the machining accuracy of the machine tool can be maximized, and the stability and reliability of the machine tool can be improved.

[0042] Furthermore, the cooling and load compensation device for the ram spindle according to the present invention, and the machine tool including the device, have the following effects: by simply and quickly detecting the decrease in machining accuracy caused by thermal deformation of the ram spindle, damage or accidents caused by short circuits or rust can be prevented in advance, and the convenience of the staff can be improved.

[0043] Furthermore, the cooling and load compensation device for the slide spindle according to the present invention, and the machine tool including the device, have the following effects: they can reduce the processing cost, maintenance cost, and time of the workpiece, and, with the reduction of non-processing time, they can improve the productivity of the machine tool.

[0044] Furthermore, the cooling and load compensation device for the ram spindle according to the present invention, and the machine tool including the device, have the following effects: by miniaturizing the cooling and load compensation device for the ram spindle, installation and manufacturing costs can be reduced, and the compactness of the machine tool can be achieved. Attached Figure Description

[0045] Figure 1 A diagram showing the displacement due to thermal deformation in a machine tool that moves the ram spindle relative to the saddle via a box-shaped guideway.

[0046] Figure 2 A conceptual diagram of a machine tool including a cooling and load compensation device for a slide spindle according to the present invention is shown.

[0047] Figure 3 A conceptual diagram of a cooling and load compensation device for a slide spindle according to the present invention is shown.

[0048] Figure 4 Show along Figure 3 A cross-sectional view of the BB line.

[0049] Figure 5 This is a conceptual diagram illustrating the state in which clamping bars are provided on the cooling and load compensation device of the slide spindle according to the present invention.

[0050] Figure 6 Show Figure 4 A partial cross-sectional view along the height direction.

[0051] Figure 7 Show Figure 6 Detailed diagram of part D.

[0052] Figure 8 A front view of the clamping bar of the cooling and load compensation device for the slide spindle according to the present invention is shown.

[0053] Figure 9 Show along Figure 3 A cross-sectional view of the FF line. Detailed Implementation

[0054] The following is a detailed description of a cooling and load compensation device for a slide spindle according to an embodiment of the present invention, and a machine tool equipped with the device. The embodiments described below are provided as examples to fully convey the spirit of the invention to those skilled in the art. Therefore, the present invention is not limited to the embodiments described below and can be embodied in other forms. Furthermore, in the figures, the size and thickness of the device are shown enlarged for convenience. Throughout the specification, the same reference numerals denote the same constituent elements.

[0055] The advantages, features, and techniques of this invention, as well as the embodiments described below, will become clear from the accompanying drawings. However, this invention is not limited to the following embodiments and can be embodied in various other forms. These embodiments make the disclosure of this invention more complete and provide a full scope of the invention to those skilled in the art. Throughout the specification, the same reference numerals denote the same constituent elements. For clarity, the dimensions and relative dimensions of layers and regions in the figures are shown enlarged.

[0056] The terminology used in this specification is for illustrative purposes and does not limit the invention. Unless otherwise specified in this specification, the singular forms also include the plural forms. The terms "comprise" and / or "comprising" as used in this specification mean that the mentioned constituent elements, steps, actions, and / or components do not exclude the presence or addition of more than one other constituent element, step, action, and / or component.

[0057] Figure 2 A conceptual diagram of a machine tool including a cooling and load compensation device for a slide spindle according to the present invention is shown. Figure 3 A conceptual diagram of a cooling and load compensation device for a slide spindle according to the present invention is shown. Figure 4 Show along Figure 3 A cross-sectional view of the BB line. Figure 5 This is a conceptual diagram illustrating the state in which clamping bars are provided on the cooling and load compensation device of the slide spindle according to the present invention. Figure 6 Show Figure 4 A partial cross-sectional view along the height direction. Figure 7 Show Figure 6 Detailed diagram of part D. Figure 8 A front view of the clamping bar of the cooling and load compensation device for the slide spindle according to the present invention is shown. Figure 9 Show along Figure 3 A cross-sectional view of the FF line.

[0058] The terms used below are defined as follows. "Horizontal direction" refers to the transverse direction on the same component, i.e. Figures 2 to 4 In the Y-axis direction, "vertical direction" refers to the longitudinal direction on the same component that is orthogonal to the horizontal direction. Figures 2 to 4 In the X-axis direction, "height direction" refers to the vertical direction on the same component, which is orthogonal to the horizontal and vertical directions. Figures 2 to 4 The Z-axis direction. Additionally, "above" refers to above in the "height direction," that is, Figures 2 to 4 The Z-axis points upwards, while "downwards" (or "lower part") refers to the downward direction in the "height direction," i.e. Figures 2 to 4 The center direction is downwards along the Z-axis. Additionally, "front" refers to the front of the component in the "vertical direction," i.e. Figure 2 The surface in the direction where the saddle and ram spindle are set on the crossbeam, "behind (rear)" refers to the rear in the "vertical direction" on the same component, that is... Figure 2 You can see the opposite side of the beam's direction. Additionally, "inner (middle)" refers to the side of the same component that is relatively close to the center. Figures 2 to 9 The inner side of each component or part; the outer side refers to the side of the same component that is relatively far from the center. Figures 2 to 8The outer side of each component or constituent part.

[0059] refer to Figures 2 to 9 This describes the cooling and load compensation device 10 for the slide spindle according to the present invention, and the machine tool 1 including the device. Figure 2 As shown, a machine tool 1 including the cooling and load compensation device for the ram spindle of the present invention includes: a bed 2, a worktable 3, a pair of columns 4, a crossbeam 5, a saddle 6, a ram spindle 7, and a cooling and load compensation device 10 for the ram spindle.

[0060] The bed 2 is installed on the ground. Alternatively, the bed 2 can also be installed on a foundation where the foundation has been constructed using concrete or similar materials.

[0061] The worktable 3 is horizontally movable on the upper part of the bed 2 in the vertical direction (X-axis direction).

[0062] A pair of uprights 4 are arranged opposite each other on both sides of the bed 2 in the horizontal direction (Y-axis direction) and extend in the vertical direction (Z-axis direction).

[0063] The crossbeam 5 can be moved up and down along the height direction (Z-axis direction) on a pair of columns.

[0064] The saddle 6 is movable on the crossbeam in the horizontal direction. That is, the saddle is moved left and right along the crossbeam in the horizontal direction (Y-axis direction) by the drive of the drive unit.

[0065] The ram spindle 7 is mounted on the saddle and can be moved up and down along the saddle in the height direction. That is, the ram spindle is moved up and down along the saddle in the height direction by the drive unit.

[0066] The cooling and load compensation device 10 for the ram spindle cools the ram spindle and compensates for the load when the ram spindle expands thermally.

[0067] That is, the cooling and load compensation device 10 for the ram spindle includes: a transfer unit 100 for transferring the ram spindle relative to the saddle via a box-shaped guide rail; a cooling unit 200 for cooling the ram spindle; and a load compensation unit 300 for automatically compensating for the load applied to the saddle from the ram spindle.

[0068] The reference surface is formed by the inner part of the saddle adjacent to the drive unit and the part adjacent to the outer corner of the slide spindle. There are multiple reference surfaces. The clamping bars are arranged between the upper and lower parts of the inner part of the saddle and the part adjacent to the outer corner of the slide spindle, respectively, with the reference surfaces as the center. The clamping bars are arranged between the upper and lower parts of the inner part of the saddle and the part adjacent to the outer corner of the slide spindle, respectively, with the reference surfaces as the reference surfaces and the diagonal line passing through the non-adjacent corners of the slide spindle as the reference.

[0069] When the slide shaft undergoes thermal deformation, the cooling unit cools the slide shaft. When the load on the clamping bar changes due to thermal deformation of the slide shaft, the load is automatically compensated to maintain a constant surface pressure acting on the clamping bar.

[0070] Therefore, a machine tool including the cooling and load compensation device of the slide spindle according to the present invention can reduce the processing cost, maintenance cost and time of the workpiece, and improve the productivity of the machine tool by reducing non-processing time. In addition, by miniaturizing the cooling and load compensation device of the slide spindle, installation and manufacturing costs can be reduced, and the machine tool can be made more compact.

[0071] refer to Figures 3 to 9 The cooling and load compensation device 10 for the ram spindle of the present invention will be described. The cooling and load compensation device 10 for the ram spindle includes: a saddle 6 configured to be movable along a crossbeam; a ram spindle 7 configured to be movable along the saddle; a conveying unit 100; a cooling unit 200; and a load compensation unit 300.

[0072] The transfer unit 100 transfers the ram spindle relative to the saddle via a box-shaped guide rail. That is, in the ram spindle cooling and load compensation device according to the invention, and in the machine tool including the device, the transfer unit can be any transfer unit that transfers via the box-shaped guide rail 120. For example... Figure 4 As shown, the transfer unit 100 includes a drive unit 110 that generates power for transferring the slide spindle.

[0073] Cooling unit 200 is used to cool the slide spindle. For example... Figure 4 and Figure 9 As shown, the cooling unit 200 of the cooling and load compensation device 10 for the slide spindle according to the present invention includes: a cooling flow path 210, a connecting part 220, a sensing part 230, a sealing part 240, and a support part 250.

[0074] Multiple cooling flow paths 210 are formed by passing through a portion of the ram main shaft in the height direction or inserted into a portion of the ram main shaft to allow cooling fluid to flow.

[0075] In addition, four cooling flow paths are arranged adjacent to the inner corners of the ram spindle, which are adjacent to the contact friction surfaces of the ram spindle and the saddle. That is, in Figure 4 In this design, four slide main shafts are arranged on the inner side of the slide main shaft, adjacent to the corners E1, E2, E3, and E4 of the slide main shaft. When the slide main shaft moves relative to the saddle in a box-shaped guide rail manner, these four slide main shafts are arranged at the places where the friction between the saddle and the slide main shaft occurs the most. This can minimize the heat generated by the movement of the slide main shaft and achieve miniaturization of the slide main shaft and the saddle.

[0076] The connecting parts 220 are respectively connected to the cooling flow paths and are disposed on a part of the slide main shaft, and the cooling fluid is delivered to each cooling flow path or recovered or circulated.

[0077] The sensing unit 230 is disposed on the slide spindle to sense the temperature of the slide spindle. By transmitting the temperature measured by the sensing unit to the control unit, the flow rate and temperature of the cooling fluid flowing through the cooling flow path via the connecting part are adjusted, thereby preventing thermal deformation that may occur when the slide spindle moves relative to the saddle in a box-shaped guide rail manner.

[0078] A sealing element 240 is disposed inside each connection to prevent cooling fluid from leaking from the cooling flow path. This reduces equipment maintenance time and costs, and also improves productivity by reducing non-processing time.

[0079] Support parts 250 are disposed at the upper and lower parts of each cooling flow path to support the cooling flow path. That is, the cooling flow path is not formed through the slide main shaft but is inserted into the slide main shaft like a tube. In this case, the support parts 250 are used to safely and firmly support the cooling flow path formed by the tube.

[0080] In addition, such as Figure 9 As shown, the cooling and load compensation device for the ram spindle according to the present invention has a structure in which cooling fluid flows into the upper part of the ram spindle through the connecting part of the cooling unit, and cools the portion that generates heat due to the maximum friction between the ram spindle and the saddle via the cooling flow path, and then discharges from the upper part again through the cooling flow path. This fundamentally prevents the transfer of the reduced heat source to the tool mounted at the lower front end of the ram spindle, thereby improving cooling efficiency and enhancing the stability and reliability of the machine tool by minimizing the decrease in machining accuracy caused by thermal deformation.

[0081] The load compensation unit 300 includes a clamping bar 320 for adjusting the load applied from the ram spindle to the saddle. For example... Figure 6 and 7 As shown, the load compensation unit 300 of the cooling and load compensation device 10 for the ram spindle according to the present invention includes a hydraulic flow path 330 and a compensation part 340.

[0082] The hydraulic flow path 330 is formed by passing through a part of the saddle in such a way that one side is connected to the recess.

[0083] The compensation unit 340 is configured to communicate with the other side of the hydraulic flow path, and, depending on the load generated on the clamping bar, recovers hydraulic pressure from the recessed portion or supplies hydraulic pressure to the recessed portion via the hydraulic flow path. Additionally, as... Figure 7 As shown, the compensation unit 340 includes a storage unit 341, which is expandably disposed inside the compensation unit to store hydraulic pressure.

[0084] like Figures 5 to 8 As shown, each clamp 320 of the load compensation unit 300 of the cooling and load compensation device 10 for the ram spindle according to the present invention includes a main body 321, a recessed portion 322, and a sealing portion 323.

[0085] The main body 321 includes: a horizontal portion 321a, which is formed parallel to the height direction on one side; and a tapered portion 321b, which gradually tapers along the height direction on the other side and contacts the saddle. The main body 321 is shaped like a saddle strip, with one side inclined and elongated in the vertical direction to a predetermined length.

[0086] The recess 322 is formed in part of the tapered portion to accommodate hydraulic pressure.

[0087] The sealing part 323 prevents hydraulic pressure from leaking from the recess. That is, the sealing part is provided on the outer peripheral surface of the recess to prevent hydraulic pressure from leaking to the outside of the recess when the clamping bar is set between the saddle and the ram spindle.

[0088] In addition, the clamps 320 of the load compensation unit are provided in multiple ways between the saddle 6 and the ram spindle 7, except for the reference surface 310 on the inner side of the saddle that is in close contact with the ram spindle, in a horizontal direction (Y-axis direction) or a vertical direction (X-axis direction) corresponding to the reference surface 310.

[0089] In addition, the clamping bars 320 are respectively inserted between the inner part of the saddle that is opposite to each reference surface and the part that is adjacent to the outer corner of the slide main shaft, with the diagonal AA passing through the non-adjacent corners of the slide main shaft as a reference, centered on the multiple reference surfaces.

[0090] In this invention, multiple reference surfaces 310 are formed on a portion of the inner side of the saddle 6 adjacent to the drive unit 110 and a portion of the outer side of the slide spindle 7. That is, as... Figure 4 As shown, reference surface 310 is based on the diagonal line AA passing through corners E1 and E3, and four points E1, E2, and E3 are formed in a "┐" shape at the points where the inner side of the saddle 6 and the outer corner of the slide ram spindle 7 are directly in contact.

[0091] Since there are four reference surfaces in a "┐" shape at locations E1, E2, and E3, with the diagonal of AA as the reference, each clamping bar 320 is respectively set on the four surfaces adjacent to the "└" shaped saddle and the slide main shaft, with the diagonal of AA passing through corners E1 and E3 of the slide main shaft as the reference, corresponding to the four reference surfaces in the horizontal and vertical directions.

[0092] Specifically, the first clamping strip is inserted vertically at point E1, relative to the reference plane perpendicular to corner E2, between the saddle and the ram spindle. The second clamping strip is inserted vertically at point E4, relative to the reference plane perpendicular to corner E3. The third clamping strip is inserted horizontally at point E4, relative to the reference plane formed horizontally at corner E1. The fourth clamping strip is inserted horizontally at point E3, relative to the reference plane formed horizontally at corner E2. As a result, the four clamping strips are arranged in a "└" shape between the saddle and the ram spindle, with the diagonal line AA passing through corners E1 and E3 of the ram spindle as reference, corresponding to the four "┐" shaped reference planes.

[0093] In the cooling and load compensation device 10 of the ram spindle, when the ram spindle undergoes thermal deformation, the cooling unit cools the ram spindle. When the thermal deformation of the ram spindle causes a change in the load on the clamping bars, the load compensation unit automatically compensates for the load generated on the clamping bars and automatically keeps the surface pressure acting on the clamping bars constant. That is, when the ram spindle moves through the first, second, third, and fourth clamping bars in a box-shaped guide rail manner, or when thermal expansion occurs due to the operation of the ram spindle itself, the cooling unit mainly performs the first cooling. Only when the cooling unit fails to cool the ram spindle, causing thermal expansion and a change in the load on the clamping bars, the hydraulic pressure can be adjusted to automatically adjust the surface pressure acting on the clamping bars, thereby adjusting the pressure applied to the clamping bars and maximizing machining accuracy.

[0094] In addition, such as Figure 5 As shown, four clamping strips are respectively installed between the upper and lower parts of the inner portion of the saddle facing its respective reference surface and the portion adjacent to the outer corner of the ram spindle. That is, four clamping strips are inserted in a "└" shape in the upper and lower parts of the inner portion of the saddle and the portion adjacent to the outer corner of the ram spindle, so that they are aligned with the diagonal of AA relative to the "┐" shaped reference surface. Thus, a total of eight clamping strips are inserted into one saddle and one ram spindle, thereby maintaining a constant surface pressure acting on the upper and lower parts.

[0095] Therefore, according to the present invention, the cooling and load compensation device for the ram spindle and the machine tool including the device, when the ram spindle, which is moved in the manner of a box-shaped guide rail, undergoes thermal deformation, the friction part of the ram spindle and the saddle is cooled by the cooling unit. When the load on the clamping bar changes due to the thermal deformation of the ram spindle, multiple clamping bars are respectively arranged between the saddle and the ram spindle, except for the reference surface that is in close contact with the inner side of the saddle and the ram spindle, corresponding to the reference surface in the horizontal or vertical direction. At this time, the load occurring on the clamping bar is automatically compensated by a hydraulic closed loop to maintain a constant surface pressure acting on the clamping bar. Thus, the machining accuracy of the machine tool can be maximized, the stability and reliability of the machine tool can be improved, and the decrease in machining accuracy caused by the thermal deformation of the ram spindle can be detected simply and quickly. Equipment damage or breakage and accidents caused by short circuits or rust can be prevented in advance, and the convenience of the staff can be sought.

[0096] refer to Figures 2 to 9 The present invention will explain the cooling and load compensation device for the slide spindle according to the present invention, and the working principle of the machine tool including the device.

[0097] During workpiece machining, the ram spindle moves continuously relative to the saddle via a box-shaped guide rail. The continuous operation of the motor mounted on the ram spindle causes thermal expansion of the ram spindle, which in turn causes deformation of the saddle due to pressure on the ram spindle. This results in changes in the tool tip position and vibration, which in turn reduces machining accuracy and causes damage to the equipment or tools.

[0098] To prevent this from happening, when the sensing unit mounted on the ram spindle senses a temperature rise in the ram spindle, it supplies cooling fluid to the connecting part. The fluid is supplied from the upper part of the ram spindle to the cooling flow path. After the cooling fluid flows along the cooling flow path to the lower part of the ram spindle to cool it, it flows back to the upper part of the ram spindle and is discharged to the outside through the connecting part. The circulation of the cooling fluid prevents the decrease in machining accuracy caused by the thermal expansion of the ram spindle in one go.

[0099] However, in cases where the ram spindle experiences significant thermal expansion due to excessive heat generation or various external factors, such as... Figure 7 As indicated by arrow L, the ram spindle presses against the saddle. As a result, the pressure is transmitted to the clamping bars, and the surface pressure between the clamping bars and the saddle changes, leading to a decrease in machining accuracy.

[0100] To prevent this situation, such as Figure 7 As shown, when the surface pressure of L acts on the clamp bar, the hydraulic pressure contained in the recess of the clamp bar moves along the hydraulic flow path to the compensation part, and the hydraulic pressure that has moved to the compensation part is stored again in the storage part. Therefore, the surface pressure of the clamp bar inserted between the saddle and the slide spindle on the saddle remains constant.

[0101] Conversely, when the surface pressure applied to the clamping bar decreases, the hydraulic pressure stored in the compensation section flows to the recess of the clamping bar to maintain the surface pressure between the clamping bar and the saddle constantly, quickly, and accurately. That is, through the clamping bar, the hydraulic flow path, and the hydraulic closed-loop system of the compensation section, the surface pressure of the clamping bar is constantly maintained when it changes due to thermal expansion and external factors. Furthermore, by supplementing the cooling unit, the machining accuracy of machine tools using box-type guideways can be maximized, resource waste can be prevented, machining costs can be saved, productivity can be increased with the increase of non-machining time, and the stability and reliability of the machine tool can also be improved. The clamping bar is inserted into a total of eight surfaces adjacent to the upper and lower "└"-shaped saddle and ram spindle. These eight surfaces correspond, in the horizontal and vertical directions, to a total of eight "┐"-shaped reference surfaces formed on the upper and lower parts, with reference to the diagonal lines AA passing through corners E1 and E3 of the ram spindle.

[0102] In the detailed description of the present invention described above, preferred embodiments have been referenced. However, it should be understood that various modifications and alterations can be made to the present invention by those skilled in the art or those with ordinary knowledge in the art, without departing from the spirit and technical scope of the invention as described in the claims. Therefore, the technical scope of the present invention is not limited to the contents described in the detailed description, but is determined by the scope of the claims.

[0103] Symbol Explanation

[0104] 1: Machine tool, 2: Bed, 3: Worktable, 4: Pair of columns, 5: Crossbeam, 6: Saddle, 7: Ram spindle, 10: Cooling and load compensation device for ram spindle, 100: Transfer unit, 200: Cooling unit, 210: Cooling flow path, 220: Connecting part, 230: Sensing part, 240: Sealing part, 250: Support part, 300: Load compensation unit, 310: Reference surface, 320: Clamping bar, 330: Hydraulic flow path, 340: Compensation part.

Claims

1. A cooling and load compensation device for a slide spindle, characterized in that, include: The saddle is designed to be movable along the crossbeam; The ram spindle is configured to be movable along the saddle. The transfer unit transfers the ram spindle to the saddle using a box-shaped guide rail. A cooling unit is used to cool the slide spindle; as well as The load compensation unit, equipped with clamping bars, is used to adjust the load applied from the ram spindle to the saddle. Multiple clamping bars are provided between the saddle and the ram spindle, except for the reference surface on the inner side of the saddle that is in close contact with the ram spindle, in a manner corresponding to the reference surface in the horizontal or vertical direction. The transfer unit includes a drive unit for generating power to transfer the slide spindle. The reference surface is formed in multiple parts on the inner side of the saddle adjacent to the drive unit and on the outer corner of the slide spindle. The clamping bars are respectively inserted between the inner portion of the saddle and the portion adjacent to the outer corner of the ram main shaft, which are centered on the plurality of reference surfaces and with reference to the diagonal line passing through the non-adjacent corners of the slide main shaft. When the slide shaft undergoes thermal deformation, the cooling unit cools the slide shaft. As the load on the clamping bar changes due to the thermal deformation of the slide shaft, the load compensation unit automatically compensates for the load occurring on the clamping bar, thereby automatically and constantly maintaining the surface pressure acting on the clamping bar. Four clamps are provided between the upper and lower portions of the inner portion of the saddle opposite each of the reference surfaces and the portion adjacent to the outer corner of the ram spindle.

2. The cooling and load compensation device for the slide spindle according to claim 1, characterized in that, The clamping strips respectively include: The main body has a horizontal part that is parallel to the height direction on one side and a tapered part that gradually tapers along the height direction on the other side and contacts the saddle. A recess, a depression formed in a portion of the tapered portion to accommodate hydraulic pressure; and A sealing portion is provided to prevent hydraulic pressure from leaking from the recess.

3. The cooling and load compensation device for the slide spindle according to claim 2, characterized in that, The load compensation unit includes: A hydraulic flow path is formed to pass through a portion of the saddle, such that one side communicates with the recess; and A compensation section is provided in communication with the other side of the hydraulic flow path, and recovers hydraulic pressure from the recess or supplies hydraulic pressure to the recess according to the load generated on the clamping bar.

4. The cooling and load compensation device for the slide spindle according to claim 3, characterized in that, The compensation section includes a storage section, which is expandable and disposed inside the compensation section for storing hydraulic fluid.

5. The cooling and load compensation device for the slide spindle according to claim 1, characterized in that, The cooling unit includes: Multiple cooling flow paths, extending through or inserted into a portion of the slide shaft in the height direction, provide cooling fluid flow; and The joint is configured in communication with each of the cooling flow paths on a portion of the slide block main shaft to transfer cooling fluid to each of the cooling flow paths or to recover or circulate the cooling fluid.

6. The cooling and load compensation device for the slide spindle according to claim 5, characterized in that, The plurality of cooling flow paths are arranged in four configurations, with the inner corner of the slide spindle adjacent to the contact friction surfaces of the slide spindle and the saddle.

7. The cooling and load compensation device for the slide spindle according to claim 6, characterized in that, The cooling unit also includes: A sensing unit, disposed on the slide spindle, is used to sense the temperature of the slide spindle; and A sealing portion is disposed inside each of the joints to prevent cooling fluid from leaking from the cooling flow path.

8. The cooling and load compensation device for the slide spindle according to claim 7, characterized in that, The cooling unit further includes a support portion disposed at the upper and lower parts of each cooling flow path to support the cooling flow path.

9. A machine tool, characterized in that, include: Bed frame; A pair of uprights are provided on both sides of the bed, extending along the height direction; The crossbeam is configured to be movable along the pair of columns; The saddle is configured to be movable along the crossbeam; The ram spindle is configured to be movable along the saddle; and The cooling and load compensation device for the ram spindle cools the ram spindle and compensates for the load when the ram spindle expands thermally. The cooling and load compensation device for the slide spindle includes: The transfer unit includes a drive unit, which transfers the ram spindle of the saddle using a box-shaped guide rail. A cooling unit for cooling the slide spindle; and The load compensation unit has multiple clamping bars arranged between the saddle and the ram spindle, except for the reference surface on the inner side of the saddle that is in close contact with the reference surface in the horizontal or vertical direction, and automatically compensates for the load applied to the saddle from the ram spindle. The clamping strips respectively include: The main body has a horizontal part that is parallel to the height direction on one side and a tapered part that gradually tapers along the height direction on the other side and contacts the saddle. A recess, a depression formed in a portion of the tapered portion to accommodate hydraulic pressure; and A sealing portion is provided to prevent hydraulic pressure from leaking from the recess. When the slide shaft undergoes thermal deformation, the cooling unit cools the slide shaft. As the load applied to the clamping bars changes due to the thermal deformation of the slide shaft, the unit automatically compensates for the load to maintain a constant surface pressure on the clamping bars. The reference surface is formed in multiple ways, and consists of a portion of the inner side of the saddle adjacent to the drive unit and a portion of the outer corner of the slide spindle that are in close contact with each other. The clamping bars are arranged 4 times, centered on the multiple reference surfaces, between the upper and lower parts of the inner part of the saddle and the part adjacent to the outer corner of the slide main shaft, with reference to the diagonal line passing through the non-adjacent corners of the slide main shaft.

Images