A moving crossbeam machine tool with internal constraint structure

Abstract

The present invention discloses a movable crossbeam machine tool with an internal constraint structure, comprising: a machine tool spindle, a turntable and a bed; at least two guide rails are arranged in the X-axis direction, the Y-axis direction and the Z-axis direction, and at least two guide rails in the same axial direction include at least one pair of guide rails that are not in the same coordinate plane, and these guide rails form an internal constraint space; the overlap area of ​​at least two internal constraint spaces is a motion space, and the motion space is the motion area of ​​the tool tip point of the machine tool spindle during processing; the turntable is fixed on the bed, and the workpiece on the turntable coincides with the motion space through the linear displacement of the machine tool spindle. By arranging at least two guide rails in non-same coordinate planes in three axial directions, optimizing the guide rail layout, and utilizing the internal constraints of the machine tool parts to move, the tool tip point is always located in a closed space, effectively constraining its movement in each axial direction, reducing the influence of cutting force, and reducing the amount of micro-displacement. The machine tool spindle is effectively prevented from being affected by the overturning moment, suppressing vibration and deformation, and ensuring processing accuracy.

Description

Technical Field

[0001] The invention relates to the technical field of machine tools, and in particular to a moving crossbeam machine tool with an internal constraint structure. Background Art

[0002] As the cornerstone of the modern equipment manufacturing industry, CNC machine tools carry the strategic mission of providing key basic equipment for the manufacturing industry. Among them, the dynamic crossbeam machine tool is favored by the high-end equipment manufacturing industry because of its design features of movable crossbeam and fixed worktable, which can reduce the influence of workpiece inertia and thus improve the stability of the processing process. In the context of the rapid development of high-end equipment manufacturing industry, the machine tool industry is in urgent need of breaking through the performance bottleneck of precision manufacturing technology. Especially in high-end manufacturing fields such as aerospace and precision instruments, with the exponential growth of ultra-precision machining demand, the requirements for dynamic stability and machining accuracy of machine tools have approached the physical limit. Studies have shown that when the machining accuracy enters the sub-micron level, the sensitivity of the machine tool structure to force response will increase nonlinearly, especially in the machine tool cutting process, the dynamic cutting force borne by the tool system has significant time-varying characteristics and multi-degree-of-freedom coupling characteristics. Under carbide milling conditions, the instantaneous cutting force peak value generated in the tool-workpiece contact area can reach more than 1,000 Newtons. This high-frequency alternating load will trigger a three-dimensional dynamic response of the machine tool structure. The overturning moment induced by the cutting torque at the joint surface of the spindle-spindle mounting structure (beam, column, etc.) can cause micro-displacement of the tool cutting point, resulting in micron-level posture deviation of the tool system. This "butterfly effect" in precision machining not only directly affects the quality of machining, but also causes systematic attenuation of machining accuracy through the error transmission mechanism.

[0003] Therefore, how to effectively control the impact of cutting force on the moving crossbeam machine tool to improve the machining accuracy of the machine tool has become a technical problem that needs to be solved urgently. Summary of the invention

[0004] The invention provides a moving crossbeam machine tool with an internal constraint structure, so as to effectively control the influence of cutting force on the moving crossbeam machine tool.

[0005] In order to achieve the above object, the technical solution of the present invention is:

[0006] A movable crossbeam machine tool with an internal constraint structure, comprising: a machine tool spindle, a turntable and a bed, and also comprising:

[0007] XY coordinate plane, YZ coordinate plane and ZX coordinate plane;

[0008] The XY coordinate plane is a plane perpendicular to the Z axis direction;

[0009] The YZ coordinate plane is a plane perpendicular to the X-axis direction;

[0010] The ZX coordinate plane is a plane perpendicular to the Y-axis direction;

[0011] At least two guide rails are arranged in the X-axis direction, the Y-axis direction and the Z-axis direction, and at least one pair of guide rails that are not in the same coordinate plane exists in the same axis direction;

[0012] Each pair of two X-direction guide rails not in the same coordinate plane, where two XY coordinate planes and two ZX coordinate planes are located, forms an X-direction subspace, and the union of the X-direction subspaces forms an X-direction inward constraint space;

[0013] Each pair of two XY coordinate planes and two YZ coordinate planes where two Y-direction guide rails are located that are not in the same coordinate plane forms a Y-direction sub-space, and the union of the Y-direction sub-spaces forms a Y-direction inward constraint space;

[0014] Each pair of two Z-direction guide rails not in the same coordinate plane, where two ZX coordinate planes and two YZ coordinate planes are located, forms a Z-direction sub-space, and the union of the Z-direction sub-spaces forms a Z-direction inward constraint space;

[0015] The overlapping area of ​​at least two of the X-inward constraint space, the Y-inward constraint space and the Z-inward constraint space is the motion space, and the motion space is the motion area of ​​the tool tip point of the machine tool spindle during machining;

[0016] The turntable is fixed on the bed, and the machine tool spindle is arranged on the bed through an X-guide rail. The workpiece on the turntable is made to coincide with the movement space through the linear displacement of the machine tool spindle.

[0017] Furthermore, the motion space is an area where the X-direction inward constraint space, the Y-direction inward constraint space and the Z-direction inward constraint space overlap.

[0018] Further, a motion plane is formed between two guide rails on the same axial direction that are not in the same coordinate plane;

[0019] During the machining process, the tool tip point can coincide with the motion plane in the X-axis direction or the Y-axis direction.

[0020] Further, a motion plane is formed between two guide rails on the same axial direction that are not in the same coordinate plane;

[0021] In at least one axial direction, the movement plane can pass through the workpiece on the turntable.

[0022] Furthermore, in at least one of the X-axis direction, the Y-axis direction and the Z-axis direction, no less than three guide rails are provided.

[0023] Furthermore, in an axial direction where no less than three guide rails are provided, a prismatic space formed with the guide rails as edges is a guide rail constraint space, and the guide rail constraint space replaces the inner constraint space in the corresponding axial direction to form the motion space.

[0024] Furthermore, the bed includes a main body and a support column fixed on the main body, and two Y-guide rails that are not in the same coordinate plane are respectively arranged on the main body and the support column.

[0025] Furthermore, it also includes a crossbeam, wherein the crossbeam includes a first main body and a second main body fixed on the first main body;

[0026] The first body is arranged on a Y guide rail provided on the body;

[0027] The second body is arranged on a Y guide rail provided on the support column;

[0028] Two X-guide rails that are not in the same coordinate plane are respectively arranged on the first body and the second body.

[0029] Furthermore, it also includes a saddle and a ram, wherein the ram is arranged on the saddle through a Z guide rail, and the machine tool spindle is arranged on the ram;

[0030] The saddle is arranged on an X-guide rail provided on the crossbeam.

[0031] Further, the saddle includes a frame, a first extension portion and a second extension portion;

[0032] The ram is arranged in the frame through a Z guide rail;

[0033] The first extension portion extends from the frame along the Z-axis direction, and the first extension portion is arranged on an X-guide rail provided on the first main body;

[0034] The second extension portion extends from the frame along the X-axis direction, and the second extension portion is disposed on an X-direction guide rail disposed on the second body.

[0035] Furthermore, the crossbeam further includes a side wall connecting the first body and the second body;

[0036] The first body, the second body and the side wall form a space for accommodating the turntable and the supporting column.

[0037] Furthermore, it also includes a swing milling head, and a motion plane is formed between two guide rails on the same axial direction but not on the same coordinate plane. During the processing, the swing axis of the swing milling head and the motion plane on at least one axial direction have an intersection, and the tool tip point of the swing milling head coincides with the intersection.

[0038] Furthermore, the turntable is a dual-axis turntable, which can fix the workpiece, and the envelope surface of the to-be-processed portion of the workpiece is within the motion space.

[0039] Furthermore, the angular swing milling head is a single-swing angular swing milling head, and during the machining process, the swing axis of the angular swing milling head is located in the motion plane in at least one axial direction.

[0040] Furthermore, the angular swing milling head is a double-swing angular swing milling head, and during the machining process, the swing axis of the angular swing milling head is located in the motion plane in at least one axial direction.

[0041] Furthermore, the swing angle milling head is a non-orthogonal swing angle milling head, and the tool tip point of the non-orthogonal swing angle milling head is located on the swing axis of the non-orthogonal swing angle milling head.

[0042] Beneficial effects:

[0043] The present invention provides a moving crossbeam machine tool with an internal constraint structure. At least one pair of guide rails that are not in the same coordinate plane are arranged in the X-axis direction, the Y-axis direction and the Z-axis direction, so that at least two of the X-direction internal constraint space, the Y-direction internal constraint space and the Z-direction internal constraint space respectively formed by the guide rails in the X-axis direction, the Y-axis direction and the Z-axis direction can intersect to form a closed motion space, thereby optimizing the layout of the guide rail structure. The guide rails are used to internally constrain the motion of machine tool components so that the tool tip point is always located in the closed motion space during the machining process, thereby effectively constraining the tool tip point in the X-axis, Y-axis and Z-axis directions, greatly reducing the influence of the cutting force on the tool tip point, thereby reducing the micro-displacement of the tool tip point; effectively avoiding the influence of the overturning moment on the machine tool spindle during operation, suppressing vibration and deformation, and ensuring the machining accuracy of the machine tool.

[0044] The machine tool spindle is set on the bed through guide rails. The linear displacement of the machine tool spindle ensures that the workpiece on the turntable fixed to the bed can coincide with the motion space. During the processing, the workpiece does not need to perform reciprocating linear displacement, reducing the influence of the workpiece inertia, thereby improving the stability of the processing process. BRIEF DESCRIPTION OF THE DRAWINGS

[0045] In order to more clearly illustrate the embodiments of the present invention or the technical solutions in the prior art, the following briefly introduces the drawings required for use in the embodiments or the description of the prior art. Obviously, the drawings described below are some embodiments of the present invention. For ordinary technicians in this field, other drawings can be obtained based on these drawings without paying creative labor.

[0046] Figure 1 A schematic diagram of a movable crossbeam machine tool with an internal constraint structure disclosed in Example 1 of the present invention;

[0047] Figure 2 It is a structural schematic diagram of a moving crossbeam machine tool with an internal constraint structure disclosed in Example 1 of the present invention;

[0048] Figure 3 A side view of a moving crossbeam machine tool with an internal constraint structure disclosed in Example 1 of the present invention;

[0049] Figure 4 A front view of a moving crossbeam machine tool with an internal constraint structure disclosed in Example 1 of the present invention;

[0050] Figure 5 A top view of a moving crossbeam machine tool with an internal constraint structure disclosed in Example 1 of the present invention;

[0051] Figure 6 It is a structural schematic diagram of a bed of a moving crossbeam machine tool with an internal constraint structure disclosed in Example 1 of the present invention;

[0052] Figure 7 A schematic structural diagram of a crossbeam of a moving crossbeam machine tool with an internal constraint structure disclosed in Example 1 of the present invention;

[0053] Figure 8 This is a schematic structural diagram of a saddle of a moving beam machine tool with an internal constraint structure disclosed in Example 1 of the present invention;

[0054] Fig. 9 A schematic diagram of an X-direction inner constraint space of a moving crossbeam machine tool with an inner constraint structure disclosed in Embodiment 1 of the present invention;

[0055] Fig.10 A schematic diagram of the Y-direction inward constraint space of a moving crossbeam machine tool with an internal constraint structure disclosed in Example 1 of the present invention;

[0056] Fig.11 for Fig.10 Decomposition diagram of Figure 1 ;

[0057] Fig.12 for Fig.10 Decomposition diagram of Figure 2 ;

[0058] Fig.13 A schematic diagram of the Z-direction inward constraint space of a moving crossbeam machine tool with an internal constraint structure disclosed in Example 1 of the present invention;

[0059] Fig.14 A schematic diagram of the guide rail constraint space in the Y-axis direction of a moving crossbeam machine tool with an internal constraint structure disclosed in Example 1 of the present invention;

[0060] Fig.15 A schematic diagram of the guide rail constraint space in the Z-axis direction of a moving crossbeam machine tool with an internal constraint structure disclosed in Example 1 of the present invention;

[0061] Fig.16This is a schematic diagram of the coordination of a swing milling head and a slide of a moving crossbeam machine tool with an internal constraint structure disclosed in Example 2 of the present invention.

[0062] In the figure:

[0063] 1. Bed; 11. Main body; 12. Support column;

[0064] 2. Swing angle milling head;

[0065] 3. cross beam; 31. first main body; 32. second main body; 33. side wall;

[0066] 4. Sliding saddle; 41. Frame; 42. First extension portion; 43. Second extension portion;

[0067] 5. Sliding ram;

[0068] 6. Turntable;

[0069] 71. a first X-direction guide rail; 72. a second X-direction guide rail;

[0070] 81, first Y-direction guide rail; 82, second Y-direction guide rail; 83, third Y-direction guide rail; 84, fourth Y-direction guide rail;

[0071] 91, first Z-direction guide rail; 92, second Z-direction guide rail; 93, third Z-direction guide rail;

[0072] A1, motion plane;

[0073] X1, X-direction inward constraint space;

[0074] Y1, Y-direction inner constraint space; Y11, first Y-direction subspace; Y12, second Y-direction subspace; Y13, third Y-direction subspace; Y14, fourth Y-direction subspace;

[0075] Z1, Z-direction inner constraint space; Z11, first Z-direction subspace; Z12, second Z-direction subspace;

[0076] N. Sports space. DETAILED DESCRIPTION

[0077] In order to make the purpose, technical solution and advantages of the embodiments of the present invention clearer, the technical solution in the embodiments of the present invention will be clearly and completely described below in conjunction with the drawings in the embodiments of the present invention. Obviously, the described embodiments are part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the present invention.

[0078] The accuracy of machine tools is affected by many factors, including the structural design of machine tools, drive systems and control systems, thermal errors, tool wear, and measurement and feedback systems. In order to improve the accuracy of machine tools, we can start from these aspects or take comprehensive measures. Since the structural design of machine tools is the basis of the entire machine tool, if we want to improve the accuracy of machine tools, the first task is to optimize the design of the machine tool structure.

[0079] At present, machine tools are mainly divided into horizontal machine tools, vertical machine tools and gantry machine tools. The various components of these machine tools are connected in sequence to form an open chain structure, which inevitably forms a cantilever structure for the machine tool spindle; however, the cutting force borne by the tool tip during the machining process mainly acts on the connection between it and the adjacent components, which makes the rigidity of the machine tool directly affect the stress state of the tool tip and the stability of the machining accuracy.

[0080] The existing machine tool structure mainly improves the rigidity of the entire machine tool by enhancing the static rigidity of each component. However, in actual applications, it is found that under the influence of cutting force, gravity, and acceleration, the dynamic rigidity of the machine tool components is insufficient, resulting in irregular tiny displacements of the tool tip, which significantly affects the machining accuracy of the machine tool. This makes us realize that improving the dynamic rigidity of the machine tool is particularly important for improving the machining accuracy of the machine tool.

[0081] Machine tools include linear motion axes and rotating axes to achieve the processing of complex parts. This requires that the various components of the machine tool linear axis must be connected and supported by guide rails, so that the guide rails bear the force and ensure the accuracy of movement. During the machine tool processing process, if the dynamic stiffness of the guide rail is insufficient, it will cause the guide rail to deform, which will directly affect the processing accuracy of the machine tool and reduce the processing quality. This means that the dynamic stiffness of the machine tool depends to a large extent on the dynamic stiffness of the guide rail. In other words, the higher the dynamic stiffness of the guide rail, the smaller the impact on the processing accuracy. On the contrary, the lower the dynamic stiffness of the guide rail, the greater the impact on the processing accuracy. However, due to the mechanical properties of the material, the improvement of the dynamic stiffness of the guide rail is limited, which requires us to start from other directions to improve the dynamic stiffness of the guide rail.

[0082] Through research and analysis, it is found that the linear motion of machine tool parts is usually supported by double guide rails. The double guide rails are located in the same plane and are easily affected by the overturning moment during operation, resulting in vibration and deformation, which is not conducive to the precision machining of the entire machine tool. Therefore, this application starts with optimizing the machine tool structure layout and guide rail layout to improve the dynamic stiffness of the guide rail, thereby improving the stiffness of the entire machine tool.

[0083] Embodiment 1:

[0084] This embodiment provides a movable beam machine tool with an internal constraint structure, such as Figures 2 to 5 As shown, it includes: a machine tool spindle, a turntable 6 and a bed 1, as shown Figure 1 As shown, it also includes:

[0085] XY coordinate plane, YZ coordinate plane and ZX coordinate plane;

[0086] The XY coordinate plane is a plane perpendicular to the Z axis direction;

[0087] The YZ coordinate plane is a plane perpendicular to the X-axis direction;

[0088] The ZX coordinate plane is a plane perpendicular to the Y-axis direction;

[0089] At least two guide rails are arranged in the X-axis direction, the Y-axis direction and the Z-axis direction, and at least one pair of guide rails that are not in the same coordinate plane exists in the same axis direction;

[0090] Each pair of two X-direction guide rails not in the same coordinate plane, where two XY coordinate planes and two ZX coordinate planes are located, forms an X-direction sub-space, and the union of the X-direction sub-spaces forms an X-direction inward constraint space X1;

[0091] Each pair of two XY coordinate planes and two YZ coordinate planes where two Y-direction guide rails are located that are not in the same coordinate plane forms a Y-direction sub-space, and the union of the Y-direction sub-spaces forms a Y-direction inward constraint space Y1;

[0092] Each pair of two Z-direction guide rails not in the same coordinate plane, where two ZX coordinate planes and two YZ coordinate planes are located, forms a Z-direction sub-space, and the union of the Z-direction sub-spaces forms a Z-direction inward constraint space Z1;

[0093] The area where at least two of the X-direction inward constraint space X1, the Y-direction inward constraint space Y1 and the Z-direction inward constraint space Z1 overlap is the motion space N, and the motion space N is the motion area of ​​the tool tip point of the machine tool spindle during the machining process, and the tool tip point is the point that the tool tip point of the machine tool spindle is to reach;

[0094] The turntable 6 is fixed on the bed 1 , and the machine tool spindle is arranged on the bed 1 through an X-guide rail. The workpiece on the turntable 6 is made to coincide with the motion space N through the linear displacement of the machine tool spindle.

[0095] The present embodiment provides a moving crossbeam machine tool with an internal constraint structure. At least one pair of guide rails (two guide rails form a pair) that are not in the same coordinate plane are arranged in the X-axis direction, the Y-axis direction and the Z-axis direction, so that at least two of the X-direction internal constraint space X1, the Y-direction internal constraint space Y1 and the Z-direction internal constraint space Z1 formed by the guide rails in the X-axis direction, the Y-axis direction and the Z-axis direction respectively can intersect to form a closed motion space N, thereby optimizing the layout of the guide rail structure, utilizing the guide rails to perform internal constraints on the motion of machine tool components, so that the tool tip point is always located in the closed motion space N during the machining process, and effectively constraining the tool tip point in the X-axis, Y-axis and Z-axis directions, greatly reducing the influence of the cutting force on the tool tip point, thereby reducing the micro-displacement of the tool tip point; effectively avoiding the influence of the overturning moment on the machine tool spindle during operation, suppressing vibration and deformation, and ensuring the machining accuracy of the machine tool.

[0096] The machine tool spindle is set on the bed 1 through a guide rail. Through the linear displacement of the machine tool spindle, it is ensured that the workpiece on the turntable 6 fixed to the bed 1 can coincide with the motion space N. During the processing, the workpiece does not need to perform reciprocating linear displacement, reducing the influence of the workpiece inertia, thereby improving the stability of the processing process.

[0097] In this embodiment, in order to facilitate the construction of various spaces and planes, the guide rails need to be conceptualized as lines within the space to serve as a reference for the construction of the space and plane;

[0098] Specifically, when the area of ​​the guide rail used to carry the machine tool component is the guide rail surface of the guide rail itself (with Figure 4 For example, Figure 4 The first X guide rail 71 in the figure meets this working condition), and the guide rail can be conceptualized as the center line of the guide rail surface;

[0099] When the area of ​​the guide rail used to carry machine tool components is the edge lines on both sides of the guide rail surface of the guide rail itself (with Figure 4 For example, Figure 4 The second X-guide rail 72 in FIG. 1 meets this working condition), and the guide rail can be conceptualized as the edge line of the guide rail surface.

[0100] In this embodiment, the coordinate planes include an XY coordinate plane, a YZ coordinate plane, and a ZX coordinate plane;

[0101] The XY coordinate plane is a plane parallel to the XY plane, mathematically called the z=k plane, whose normal vector is the same as that of the standard XY plane, and k is a constant;

[0102] The YZ coordinate plane is a plane parallel to the YZ plane, mathematically called the x=k plane, whose normal vector is the same as that of the standard YZ plane, and k is a constant;

[0103] The ZX coordinate plane is a plane parallel to the ZX plane, mathematically called the y=k plane, whose normal vector is the same as that of the standard ZX plane, and k is a constant.

[0104] For the guide rails in the X-axis direction, the corresponding constant k of each pair of two X-direction guide rails that are not in the same coordinate plane is not equal to the two XY coordinate planes (z=k plane);

[0105] For each pair of two X-direction guide rails that are not in the same coordinate plane, the corresponding constant k is not equal to the two ZX coordinate planes (y=k plane);

[0106] The X-direction subspace is a quadrangular prism space with open ends surrounded by two XY coordinate planes and two ZX coordinate planes where two pairs of X-direction guide rails that are not in the same coordinate plane are located;

[0107] When the number of X-direction rails is equal to 2, there is only one pair of X-direction rails that are not in the same coordinate plane, so there is only one X-direction sub-space, and the X-direction inward constraint space X1 is equal to the X-direction sub-space;

[0108] When the number of X-direction rails is greater than 2, each additional pair of X-direction rails that are not in the same coordinate plane will increase an X-direction subspace accordingly. At this time, the X-direction inward constraint space X1 is equal to the union of multiple X-direction subspaces.

[0109] For the guide rail in the Y-axis direction, the constant k corresponding to each pair of two Y-direction guide rails that are not in the same coordinate plane is not equal to the two XY coordinate planes (z=k plane) where the guide rails are located;

[0110] For each pair of two Y-direction guide rails that are not in the same coordinate plane, the corresponding constant k is not equal to the two YZ coordinate planes (x=k plane);

[0111] The Y-direction subspace is a quadrangular prism-shaped space with open ends surrounded by two XY coordinate planes and two YZ coordinate planes where each pair of two Y-direction guide rails that are not in the same coordinate plane are located;

[0112] When the number of Y-direction guide rails is equal to 2, there is only one pair of Y-direction guide rails that are not in the same coordinate plane, so there is only one Y-direction sub-space, and the Y-direction inward constraint space Y1 is equal to the Y-direction sub-space;

[0113] When the number of Y-direction guide rails is greater than 2, each additional pair of Y-direction guide rails that are not in the same coordinate plane will correspondingly increase a Y-direction sub-space. At this time, the Y-direction inward constraint space Y1 is equal to the union of multiple Y-direction sub-spaces.

[0114] For the guide rails in the Z-axis direction, the constant k corresponding to the two ZX coordinate planes (y=k plane) where the two Z-direction guide rails are located that are not in the same coordinate plane is not equal;

[0115] For each pair of two ZY coordinate planes (x=k plane) where two Z-guide rails are not in the same coordinate plane, the corresponding constant k is not equal.

[0116] The Z-direction subspace is a quadrangular prism-shaped space with two open ends surrounded by two ZX coordinate planes and two YZ coordinate planes where each pair of two Z-direction guide rails that are not in the same coordinate plane are located;

[0117] When the number of Z-direction guide rails is equal to 2, there is only one pair of Z-direction guide rails that are not in the same coordinate plane, so there is only one Z-direction sub-space, and the Z-direction inward constraint space Z1 is equal to the Z-direction sub-space;

[0118] When the number of Z-direction guide rails is greater than 2, each additional pair of Z-direction guide rails that are not in the same coordinate plane will correspondingly increase a Z-direction sub-space. At this time, the Z-direction inward constraint space Z1 is equal to the union of multiple Z-direction sub-spaces.

[0119] In a specific embodiment, Figure 1 As shown, the motion space N is the overlapping area of ​​the X-inward constraint space X1, the Y-inward constraint space Y1, and the Z-inward constraint space Z1.

[0120] By overlapping the X-inward constraint space X1, the Y-inward constraint space Y1 and the Z-inward constraint space Z1 to form a closed motion space, the tool tip can always be located in the closed space when it moves in the three directions during the machining process. During the machining process, the cutting force on the tool tip can be enclosed in the motion space, and a pair of guide rails on the three axes that are not in the same coordinate plane always maintain the state of supporting the tool tip at both ends, optimizing the force on the guide rails; at the same time, the machine tool parts moving in the three axes can also always maintain support at both ends, which can optimize the force on the guide rails and support and limit the machine tool parts. Finally, through the above-mentioned structural layout, the weak links and areas with insufficient dynamic stiffness are eliminated, thereby improving the overall stiffness of the machine tool, reducing the micro-displacement of the tool tip, avoiding the influence of the overturning moment, and then suppressing vibration and deformation, ensuring the machining stability of the tool tip.

[0121] At the same time, the improvement of dynamic stiffness can also reduce the wear and aging of machine tools, ensure the machining accuracy of machine tools, and extend the service life of machine tools.

[0122] In addition, since the motion space N is formed by the guide rails, the motion space N must be between a pair of guide rails in the three axial directions that are not in the same coordinate plane, which means that the motion area must be located inside the support structure of the machine tool; compared with the support structure of existing machine tools (bed, column, saddle and slide, etc.), which can only provide support outside the motion area of ​​the tool tip, the machine tool of the present application can be reduced in size and weight when achieving the same size processing area, which is beneficial to improve the overall rigidity of the machine tool and reduce the cost of the machine tool.

[0123] In a specific embodiment, Figure 4 As shown, a motion plane A1 is formed between two guide rails on the same axial direction that are not in the same coordinate plane;

[0124] During the machining process, the tool tip point can coincide with the motion plane A1 in the X-axis direction or the Y-axis direction.

[0125] When the tool tip coincides with the motion plane A1, the motion plane A1 supports the tool tip, and the tool tip does not form a cantilever structure relative to the motion plane A1, thereby ensuring that the tool tip maintains stable accuracy during the plane machining process.

[0126] The establishment of the motion plane A1 also adopts the aforementioned method of conceptualizing the guide rail as a line in space. On the same axis, the line formed by the conceptualization of two guide rails that are not in the same coordinate plane, the plane where they are located is the motion plane A1.

[0127] In a specific embodiment, Figure 4 As shown, a motion plane A1 is formed between two guide rails on the same axial direction that are not in the same coordinate plane;

[0128] In at least one axial direction, the movement plane A1 can pass through the workpiece on the turntable 6 .

[0129] The motion plane A1 supports the workpiece and reduces the influence of the cutting force on the position of the workpiece, thereby maintaining stable precision during the machining process.

[0130] In a specific embodiment, at least three guide rails are provided in at least one axial direction among the X-axis direction, the Y-axis direction and the Z-axis direction.

[0131] At least three guide rails are set to achieve over-positioning. By adding additional positioning constraints to limit the freedom of the guide rails in multiple directions, the guide rails can withstand greater lateral and torsional forces, improve the dynamic stiffness of the guide rails, and thus reduce positioning errors caused by loosening or deformation of the guide rails; and increase the support points for the machine tool components connected to them, thereby improving the dynamic stiffness of the corresponding machine tool components. At the same time, it can ensure the consistency of each positioning, improve the accuracy of repeated positioning, and meet the needs of high-precision processing.

[0132] In a specific embodiment, in an axial direction where no less than three guide rails are provided, a prismatic space formed with the guide rails as edges is a guide rail constraint space, and the guide rail constraint space replaces the inner constraint space in the corresponding axial direction to form the motion space; a constraint surface is formed between two adjacent guide rails, and a plurality of the constraint surfaces are connected to form the guide rail constraint space in the corresponding axial direction.

[0133] The constraint surface is established by also using the aforementioned method of conceptualizing the guide rail as a line in space. In the axial direction with no less than three guide rails, the line formed by the conceptualization of two adjacent guide rails, and the plane where they are located together is the constraint surface;

[0134] The constraint surfaces are connected to form a guideway constraint space in the corresponding axial direction, which is a prismatic space formed by the lines formed by conceptualization as edges;

[0135] In the same axial direction, the guide rail constraint space is located in the inner constraint space. Although the line formed by the conceptualization of the guide rail is used as the reference for establishing the space, compared with the quadrangular prism-shaped inner constraint space formed by the coordinate plane, the guide rail constraint space in the corresponding axial direction formed by the constraint planes, the tool tip point can be completely located within the encirclement range of the guide rail, and the tool tip point will not form a cantilever structure for the guide rail in this direction, so the constraint effect is better, further improving the dynamic stiffness of the tool tip point, reducing the influence of the cutting force on the tool tip point, and reducing the micro-displacement of the tool tip point.

[0136] In a specific embodiment, the machine tool spindle is arranged on the bed 1 through X-guide rails, Y-guide rails and Z-guide rails, so that the machine tool spindle can perform linear displacement along the X-axis direction, the Y-axis direction and the Z-axis direction.

[0137] In a specific embodiment, Figure 6 As shown, the bed 1 includes a main body 11 and a support column 12 fixed on the main body 11, and two Y-direction guide rails that are not in the same coordinate plane are respectively arranged on the main body 11 and the support column 12.

[0138] In this embodiment, the main body 11 and the support column 12 are both provided with two Y-guide rails;

[0139] Specifically, the main body 11 is provided with a third Y-guide rail 83 and a fourth Y-guide rail 84, and the support column 12 is provided with a first Y-guide rail 81 and a second Y-guide rail 82;

[0140] The four Y guide rails (the first Y guide rail 81, the second Y guide rail 82, the third Y guide rail 83 and the fourth Y guide rail 84) form four pairs of Y guide rails that are not in the same coordinate plane, such as Fig.10 and Fig.12 As shown, four Y-direction sub-spaces are formed (the first Y-direction guide rail 81 and the third Y-direction guide rail 83 form a first Y-direction sub-space Y11, the second Y-direction guide rail 82 and the fourth Y-direction guide rail 84 form a second Y-direction sub-space Y12, the second Y-direction guide rail 82 and the third Y-direction guide rail 83 form a third Y-direction sub-space Y13, and the first Y-direction guide rail 81 and the fourth Y-direction guide rail 84 form a fourth Y-direction sub-space Y14), and the union of the four Y-direction sub-spaces is the Y-direction inward constraint space Y1;

[0141] like Fig.14 As shown, the space enclosed by the four constraint surfaces formed by the four Y-guide rails is the guide rail constraint space in the Y-axis direction.

[0142] By arranging part of the Y-guide rail on the support column 12, a stable and reliable support is provided for the Y-guide rail, vibration and deformation are suppressed, and the dynamic stiffness of the Y-guide rail is ensured.

[0143] In a specific embodiment, Figures 2 to 5 As shown, it also includes a crossbeam 3, such as Figure 7 As shown, the crossbeam 3 includes a first body 31 and a second body 32 fixed on the first body 31;

[0144] The first body 31 is disposed on a third Y guide rail 83 and a fourth Y guide rail 84 provided on the body 11;

[0145] The second body 32 is disposed on the first Y-guide rail 81 and the second Y-guide rail 82 provided on the support column 12;

[0146] Two X-guide rails that are not in the same coordinate plane are respectively arranged on the first body 31 and the second body 32;

[0147] In this embodiment, two X-guide rails (a first X-guide rail 71 and a second X-guide rail 72) are provided on the crossbeam 3, the second X-guide rail 72 is provided on the first body 31, and the first X-guide rail 71 is provided on the second body 32. The first X-guide rail 71 and the second X-guide rail 72 constitute an X-direction subspace. Fig. 9 As shown, the X-direction sub-space is equivalent to the X-direction inward constraint space X1.

[0148] In a specific embodiment, Figures 2 to 5 As shown, it also includes a saddle 4 and a ram 5, the ram 5 is arranged on the saddle 4 through a Z guide rail, and the machine tool spindle is arranged on the ram 5;

[0149] The saddle 4 is arranged on the X-guide rail provided on the crossbeam 3;

[0150] In this embodiment, if Figure 8 As shown, the slide saddle 4 includes a frame 41, a first extension portion 42 and a second extension portion 43;

[0151] The ram 5 is arranged in the frame 41 through three Z-guide rails (a first Z-guide rail 91 , a second Z-guide rail 92 and a third Z-guide rail 93 );

[0152] The first extension portion 42 extends from the frame 41 along the Z-axis direction, and the first extension portion 42 is disposed on a second X-guide rail 72 disposed on the first main body 31;

[0153] The second extension portion 43 extends from the frame 41 along the X-axis direction, and the second extension portion 43 is disposed on the first X-guide rail 71 disposed on the second main body 32;

[0154] The saddle 4 is provided with a first extension portion 42 and a second extension portion 43 to ensure that sufficient space is left at the bottom of the frame 41 to facilitate the layout of other parts of the machine tool.

[0155] The first Z guide rail 91, the second Z guide rail 92 and the third Z guide rail 93 form two pairs of Z guide rails that are not in the same coordinate plane. Fig.13 As shown, two Z-direction sub-spaces (a first Z-direction sub-space Z11 and a second Z-direction sub-space Z12) are formed, and the union of the two Z-direction sub-spaces is the Z-direction inner constraint space Z1;

[0156] like Fig.15 As shown, the space enclosed by the three constraint surfaces formed by the three Z-guide rails 9 is the guide rail constraint space in the Z-axis direction.

[0157] In a specific embodiment, Figure 7 As shown, the crossbeam 3 further includes a side wall 33 connecting the first body 31 and the second body 32;

[0158] The first body 31, the second body 32 and the side wall 33 form a space for accommodating the turntable 6 and the support column 12. This layout can not only fully utilize the higher static stiffness of the side wall 33 to provide stable support for the X-guide rail, but also improve space utilization and reduce the overall space occupied by the machine tool.

[0159] Embodiment 2:

[0160] This embodiment provides a movable crossbeam machine tool with an internal constraint structure. The main structure of this embodiment is the same as that of Embodiment 1. The difference between this embodiment and Embodiment 1 is as follows:

[0161] In this embodiment, a swing milling head 2 is also included, and a motion plane A1 is formed between two guide rails on the same axial direction that are not on the same coordinate plane. Fig.16 As shown, the angular milling head 2 is arranged on the slide 5. During the machining process, the swing axis of the angular milling head 2 intersects with at least one axial motion plane A1, and the tool tip of the angular milling head coincides with the intersection.

[0162] In this embodiment, the tool tip point of the swing milling head 2 and the tool tip point of the machine tool spindle in Embodiment 1 are the same concept.

[0163] When the tool tip of the swing milling head 2 coincides with the motion plane A1, the motion plane A1 supports the tool tip, and the tool tip does not form a cantilever structure relative to the motion plane A1, thereby reducing the impact of the cutting force on the displacement of the tool tip relative to the swing axis, thereby ensuring that the tool tip maintains stable accuracy during machining.

[0164] Preferably, the angular swing milling head 2 may be a single-swing angular swing milling head, and during the machining process, the swing axis of the angular swing milling head 2 is located within the motion plane A1 in at least one axial direction.

[0165] Preferably, the angular swing milling head 2 may be a double-swing angular swing milling head, and during the machining process, the swing axis of the angular swing milling head 2 is located within the motion plane A1 in at least one axial direction.

[0166] Preferably, the swing-angle milling head 2 may be a non-orthogonal swing-angle milling head, and the tool tip of the non-orthogonal swing-angle milling head is located on the swing axis of the non-orthogonal swing-angle milling head.

[0167] Embodiment 3:

[0168] This embodiment provides a movable crossbeam machine tool with an internal constraint structure. The main structure of this embodiment is the same as that of Embodiment 1. The difference between this embodiment and Embodiment 1 is as follows:

[0169] In this embodiment, the turntable 6 is a dual-axis turntable, and the turntable 6 can fix the workpiece. The envelope surface of the part to be processed of the workpiece is within the motion space, ensuring that the part to be processed of the workpiece can be within the motion space during the processing. The turntable 6 can be a cradle turntable or a vertical and horizontal 90° rotation worktable, or it can be other forms of dual-axis turntables.

[0170] The envelope surface of the workpiece is composed of a series of characteristic lines, which are the trajectories of the points where the tool is tangent to the workpiece surface during machining. When the tool moves along a certain trajectory, these characteristic lines will continue to change and eventually form the envelope surface of the workpiece.

[0171] Finally, it should be noted that the above embodiments are only used to illustrate the technical solutions of the present invention, rather than to limit it. Although the present invention has been described in detail with reference to the aforementioned embodiments, those skilled in the art should understand that they can still modify the technical solutions described in the aforementioned embodiments, or replace some or all of the technical features therein with equivalents. However, these modifications or replacements do not cause the essence of the corresponding technical solutions to deviate from the scope of the technical solutions of the embodiments of the present invention.

Claims

1. A moving crossbeam machine tool with an internal constraint structure, comprising: The machine tool spindle, turntable (6) and bed (1) are characterized by further comprising: XY coordinate plane, YZ coordinate plane and ZX coordinate plane; The XY coordinate plane is a plane perpendicular to the Z axis direction; The YZ coordinate plane is a plane perpendicular to the X-axis direction; The ZX coordinate plane is a plane perpendicular to the Y-axis direction; At least two guide rails are arranged in the X-axis direction, the Y-axis direction and the Z-axis direction, and at least one pair of guide rails that are not in the same coordinate plane exists in the same axis direction; Each pair of two X-direction guide rails not in the same coordinate plane, where two XY coordinate planes and two ZX coordinate planes are located, forms an X-direction subspace, and the union of the X-direction subspaces forms an X-direction inward constraint space; Each pair of two XY coordinate planes and two YZ coordinate planes where two Y-direction guide rails are located that are not in the same coordinate plane forms a Y-direction sub-space, and the union of the Y-direction sub-spaces forms a Y-direction inward constraint space; Each pair of two Z-direction guide rails not in the same coordinate plane, where two ZX coordinate planes and two YZ coordinate planes are located, forms a Z-direction sub-space, and the union of the Z-direction sub-spaces forms a Z-direction inward constraint space; The overlapping area of ​​at least two of the X-inward constraint space, the Y-inward constraint space and the Z-inward constraint space is the motion space, and the motion space is the motion area of ​​the tool tip point of the machine tool spindle during machining; The turntable (6) is fixedly mounted on the bed (1); the machine tool spindle is arranged on the bed (1) via an X-guide rail, a Y-guide rail and a Z-guide rail; and the workpiece on the turntable (6) is made to coincide with the motion space through the linear displacement of the machine tool spindle; The bed (1) comprises a main body (11) and a support column (12) fixedly mounted on the main body (11), and two Y-direction guide rails not in the same coordinate plane are respectively arranged on the main body (11) and the support column (12); It also includes a crossbeam (3), wherein the crossbeam (3) includes a first main body (31) and a second main body (32) fixed to the first main body (31); The first main body (31) is arranged on a Y-guide rail provided on the main body (11); The second body (32) is arranged on a Y-guide rail provided on the support column (12); Two X-direction guide rails that are not in the same coordinate plane are respectively arranged on the first body (31) and the second body (32); It also includes a saddle (4) and a ram (5), wherein the ram (5) is arranged on the saddle (4) via a Z-guide rail, and the machine tool spindle is arranged on the ram (5); The sliding saddle (4) is arranged on an X-guide rail provided on the crossbeam (3); The sliding saddle (4) comprises a frame (41), a first extending portion (42) and a second extending portion (43); The ram (5) is arranged in the frame (41) via a Z-guide rail; The first extension portion (42) extends from the frame (41) along the Z-axis direction, and the first extension portion (42) is arranged on an X-guide rail provided on the first main body (31); The second extension portion (43) extends from the frame (41) along the X-axis direction, and the second extension portion (43) is arranged on an X-direction guide rail provided on the second main body (32); The crossbeam (3) further comprises a side wall (33) connecting the first body (31) and the second body (32); The first body (31), the second body (32) and the side wall (33) form a space for accommodating the turntable (6) and the support column (12).

2. A movable crossbeam machine tool with an internal constraint structure according to claim 1, characterized in that: The motion space is the region where the X-direction inward constraint space, the Y-direction inward constraint space and the Z-direction inward constraint space overlap.

3. The movable crossbeam machine tool with an internal constraint structure according to claim 1, characterized in that: A motion plane is formed between two guide rails on the same axis that are not in the same coordinate plane; During the machining process, the tool tip point can coincide with the motion plane in the X-axis direction or the Y-axis direction.

4. The movable crossbeam machine tool with an internal constraint structure according to claim 1, characterized in that: A motion plane is formed between two guide rails on the same axis that are not in the same coordinate plane; In at least one axial direction, the movement plane can pass through the workpiece on the turntable (6).

5. The movable crossbeam machine tool with an internal constraint structure according to claim 1, characterized in that: In at least one of the X-axis direction, the Y-axis direction and the Z-axis direction, no less than three guide rails are provided.

6. The movable crossbeam machine tool with an internal constraint structure according to claim 5, characterized in that: In an axial direction where no less than three guide rails are provided, a prismatic space formed with the guide rails as edges is a guide rail constraint space, and the guide rail constraint space replaces the inner constraint space in the corresponding axial direction to form the motion space.

7. The movable crossbeam machine tool with an internal constraint structure according to claim 1, characterized in that: It also comprises a swing milling head (2), wherein a motion plane is formed between two guide rails on the same axial direction and not on the same coordinate plane, and during machining, a swing axis of the swing milling head (2) and the motion plane on at least one axial direction have an intersection point, and a tool tip point of the swing milling head (2) coincides with the intersection point.

8. The movable crossbeam machine tool with an internal constraint structure according to claim 1, characterized in that: The turntable (6) is a dual-axis turntable capable of fixing a workpiece, and the envelope surface of the to-be-processed portion of the workpiece is within the motion space.

9. The movable crossbeam machine tool with an internal constraint structure according to claim 7, characterized in that: The swing angle milling head (2) is a single swing angle milling head. During the machining process, the swing axis of the swing angle milling head is located within the motion plane in at least one axial direction.

10. The movable crossbeam machine tool with an internal constraint structure according to claim 7, characterized in that: The swing angle milling head (2) is a double-swing swing angle milling head. During the machining process, the swing axis of the swing angle milling head is located within the motion plane in at least one axial direction.

11. The movable crossbeam machine tool with an internal constraint structure according to claim 7, characterized in that: The swing angle milling head (2) is a non-orthogonal swing angle milling head, and the tool tip point of the non-orthogonal swing angle milling head is located on the swing axis of the non-orthogonal swing angle milling head.

Images