A double-interference solution for angle head machining of five-axis machine tools with tilting and swinging heads

Abstract

The present invention relates to the technical field of post-processing development of five-axis machine tools, and specifically to a method for solving the double-solution interference in the angle head processing of a five-axis machine tool with a tilting head. Starting from the computer-aided programming and post-processing development end, according to the algorithm of the device angle head module, the corresponding numerical control code is automatically added at the appropriate position when the NC program is output, so as to control the 4th and 5th axes of the device to select the preset non-interference solution during processing. The method for solving the double-solution interference in the angle head processing of the five-axis machine tool with a tilting head adds a specific signal in the post-processing. When the corresponding signal is given in the pre-processing, the post-processing will be processed according to the angle head program, and the interference interval will be calculated according to the angle of the feature, and then the instruction line that jumps out of the interference interval will be output to avoid the interference solution and solve the interference problem in the processing.

Description

Technical Field

[0001] The invention relates to the technical field of post-processing development of five-axis machine tools, and in particular to a double-interference solution method for angle head machining of a five-axis machine tool with an inclined swing head. Background Art

[0002] For a five-axis machine tool with a tilting head structure, when the spindle is mounted with a 90° angle head with the tool facing the positive direction of the X-axis (the negative direction is the same), due to the algorithm of the angle head module built into the device, double solutions will appear (that is, two combinations of the 4th and 5th axes that meet the processing conditions), and one of the solutions will cause interference.

[0003] The motion structure of the five-axis machine tool with tilting and swinging head: vertical structure (when B=0, the spindle axis is in the Z-axis direction), the linear axes are X, Y, and Z, and the rotation axes are B (spindle swing head) and C (turntable), where the range of B is [0, 180°], and the unit vector of the rotation center is The range of C is 360° infinite rotation, and the unit vector of the rotation center is (0, 0, 1).

[0004] If spindle machining is used, and the angle between the machining feature normal and the XY plane is α, then in order to achieve the coincidence of the tool axis and the machining feature normal in 3+2 machining, the relationship between the rotation angle β4 of the B axis and α is: cos(β4)=2×sin(α)-1. Considering the actual range of the two variables α∈[0,90] and β4∈[0,180], the corresponding function curve can be drawn according to the interval monotonicity of the sin and cos functions, as shown in Figure 1 As shown, it is a monotonically decreasing function.

[0005] At this time, let the projection line of the tool axis in the XY plane have an angle of β5 with the positive direction of the X axis, then the relationship between β5 and β4 is: Considering the actual range of the two variables β4∈[0,180] and β5∈[0,180], according to the interval monotonic property of the tan function, the corresponding function curve can be drawn, as shown in Figure 2 As shown, it is a monotonically increasing function.

[0006] If the tool is mounted on the spindle and the 90° angle head is facing the positive direction of X for machining, the new spindle can be set as spindle′, and the angle between the machining feature normal and the XY plane is still set to α. Then, in order to achieve the coincidence of the tool axis and the machining feature normal in 3+2 machining, the relationship between the rotation angle γ4 of the B axis and α is: Considering the actual range of the two variables α∈[0,45] and γ4∈[0,180], according to the interval monotonic property of the sin function, the corresponding function curve can be drawn, as shown in Figure 3As shown, the function curve is symmetric about γ4=90, that is, 1 α value corresponds to 2 γ4 values. This is the fundamental reason for the emergence of double solutions.

[0007] At this time, let the projection line of the tool axis in the XY plane have an angle of γ5 with the positive direction of the X axis, then the relationship between γ5 and γ4 is: tan(γ5) = / 2×tan(γ4). Considering the actual range of the two variables γ4∈[0,180] and γ5∈[0,180], according to the interval monotonic property of the tan function, the corresponding function curve can be drawn, as shown in Figure 4 As shown, it is a monotonically increasing function.

[0008] Specifically for the Heidenhain system's tilting head five-axis machine tool, the operating logic of its NC program is as follows: when the NC program is output through post-processing, it is calculated according to the mode of using the spindle processing. At this time, β4 and α are monotonic functions and there is no double solution problem. However, when the NC program is processed on the equipment, after the angle head module that comes with the equipment is started, the spindle changes from spindle to spindle′, and the function of β4 and α becomes the function of γ4 and α, resulting in a double solution. This double solution occurs on the equipment, which is completely outside the NC programming stage, so it cannot be directly controlled. This is also the core reason why the double solution problem is difficult to solve. Summary of the invention

[0009] In order to solve the above problems, the present invention provides a double-solution interference solution for the angle head machining of a five-axis machine tool with a tilting head. The double-solution interference solution for the angle head machining of a five-axis machine tool with a tilting head adds a specific signal in the post-processing. When the corresponding signal is given in the pre-processing, the post-processing will be processed according to the angle head program, and the interference interval will be calculated according to the angle of the feature, and then the instruction line that jumps out of the interference interval will be output, so as to avoid the interference solution and solve the interference problem in machining.

[0010] The technical solution of the present invention is as follows:

[0011] A method for solving double interference in angle head machining of a five-axis machine tool with a tilting head includes the following steps:

[0012] Step 1: Calculate the solution β4 of the B axis and the angle β5 between the projection line of the tool axis on the XY plane and the positive direction of the X axis when the spindle head NC program is output;

[0013] Step 2: Calculate the solution β of the C axis when the spindle head NC program is output c5 ;

[0014] Step 3: Calculate the solution of the B axis when the NC program is running in angle head module mode 4(1) and γ 4(2) , the angle γ between the projection line of the tool axis on the XY plane and the positive direction of the X axis 5(1) and γ 5(2) ;

[0015] Step 4: Calculate the solution of the C axis when the NC program is running in angle head module mode e5(1) and γ e5(2) ;

[0016] Step 5: Calculate the interference interval of the machining feature when the NC program runs in the angle head module mode;

[0017] Step 6: Split the interference interval;

[0018] Step 7: Calculate the SPC value of each half area out of the interference interval;

[0019] Step 8: Detect the trigger signal of the angle head program; when the signal is "N", the NC program does not use the angle head for processing and is directly output; when the signal is "Y", proceed to the next step;

[0020] Step 9: Check whether the feature is in the interference area; when the signal is "N", the NC program will not select the interference solution processing and output it directly; when the signal is "Y", according to the half area where the feature is located, the program line of the solution to avoid interference is additionally output in the NC program.

[0021] β c5 =β5-C1; where C Ⅰ Any angular position.

[0022] Assume that a 90° angle head with the tool facing the positive X direction is installed on the spindle. According to the angle α between the normal line of the feature and the XY plane, calculate the B and C axes γ in this case. 4、 γ c5 , γ c5(1,2) By γ 5(1,2) and the angular position C of the feature in the XY coordinate system Ⅰ(1,2) Calculated: γ c5(1,2) =γ 5(1,2) -C Ⅰ(1,2) ; When α<45°, the B and C axes have two solutions, and the orientation of one solution is located in the positive half of the X axis (γ 4(1)、 γ c5(1) ), the other solution is located in the negative half of the X axis (γ 4(2)、 γ c5(2) ); When α = 45°, the two solutions coincide on the positive half axis of the Y axis, i.e., γ 4(1) =γ 4(2)、 γ c5(1) =γ c5(2) .

[0023] On the XY plane, make two rays through (0, 0) at angular directions of γ5(1) and γ5(2), set them as L1 and L2 respectively, and extend L1 in the opposite direction, set it as L1′; calculate C ⅠThe two solutions C2 and C1′ of the NC program are used to calculate the specific range of the interference interval in the XY plane. When the SPC value of the NC program is βc5∈[C2,C1′], the program will select the solution of interference in the negative half of the X axis (γ 4(2) , γ c5(2) ).

[0024] When the feature is located on the negative half axis of the X axis, the corresponding C axis angle C3 is calculated. Taking C3 as the dividing line, the interference interval is divided into two half areas: [C2, C3] and [C3, C1′].

[0025] When the feature is located in the [C2, C3] half area, subtracting 90° from the SPC value can jump out of the interference interval; when the feature is located in the [C3, C1′] half area, adding 90° to the SPC value can jump out of the interference interval.

[0026] The beneficial effects of the present invention are:

[0027] 1. The present invention discloses a dual-interference solution for angle head machining of a five-axis machine tool with a tilting head. The dual-interference solution for angle head machining of a five-axis machine tool with a tilting head forms a focusing standing wave field through the curved surface structure of a resonant cavity, thereby enhancing the focusing of sound wave energy. Compared with the traditional contact ultrasonic atomization method, a smaller particle size and a more concentrated particle size distribution can be achieved.

[0028] 2. The present invention discloses a method for processing double-interference of angle head of a five-axis machine tool with a tilting head. The method significantly improves the uniformity of the film thickness of the photoresist by adjusting the process parameters of the spraying, and effectively improves the yield of the subsequent exposure process. Especially when dealing with MEMS wafers with a large aspect ratio structure, a smaller droplet size is a prerequisite for conformal coating in TSV holes.

[0029] 3. The present invention discloses a dual-interference solution for angle head machining of a five-axis machine tool with a tilting head. The dual-interference solution for angle head machining of a five-axis machine tool with a tilting head utilizes the non-contact propagation characteristics of sound waves and realizes the regulation of the sound field by optimizing the dual-interference solution for angle head machining of a five-axis machine tool with a tilting head. The photoresist droplets realize non-contact atomization by absorbing ultrasonic energy. Compared with contact ultrasonic atomization, it does not require microchannels to supply liquid to the atomization surface, which effectively avoids the problem of nozzle clogging.

[0030] 4. The present invention discloses a dual-interference solution for angle head processing of a five-axis machine tool with a tilting head. The dual-interference solution for angle head processing of a five-axis machine tool with a tilting head has a simple structural design, is easy to clean and maintain, and reduces the maintenance cost of the equipment. BRIEF DESCRIPTION OF THE DRAWINGS

[0031] By reading the detailed description of the preferred embodiment below, the scheme and advantages of the present application will become clear to those skilled in the art. The accompanying drawings are only for the purpose of illustrating the preferred embodiment and are not to be considered as limiting the present invention.

[0032] In the attached picture:

[0033] Figure 1 is the β4-α function curve;

[0034] Figure 2 is the β5-β4 function curve;

[0035] Figure 3 is the γ4-α function curve;

[0036] Figure 4 is the γ5-γ4 function curve;

[0037] Figure 5 It is a flow chart of a method for solving the double-interference problem of angle head machining of a five-axis machine tool with a tilting head according to an embodiment of the present invention;

[0038] Figure 6 Schematic diagram of the interference zone. DETAILED DESCRIPTION

[0039] The solution to the double-solution interference in angle head machining of a five-axis machine tool with a tilting head is mainly aimed at a five-axis machine tool with a tilting head structure. When the tool is installed on the spindle and the tool is facing the positive direction of the X-axis (the negative direction is the same) during 90° angle head machining, due to the algorithm of the angle head module built into the device, double solutions will appear (that is, two combinations of the 4th and 5th axes that meet the machining conditions), and one of the solutions (the one with the larger tool axis fixture on the angle head) will interfere.

[0040] The present invention starts from the computer-aided programming and post-processing development end, and according to the algorithm of the equipment angle head module, the corresponding numerical control code is automatically added at the appropriate position when the NC program is output, so as to control the 4th and 5th axes of the equipment to select the preset non-interference solution during processing. The flow chart is as follows Figure 5 shown.

[0041] The following takes the typical 3+2 processing of the five-axis machine tool with tilting and swinging head of the Heidenhain system as an example to explain its specific implementation method in detail; the machine tool structure is as follows: vertical structure, linear axes X, Y, Z, swing head B∈[0, 180°], the unit vector of the rotation center is Turntable C, 360° infinite rotation, the unit vector of the rotation center is (0, 0, 1):

[0042] 1. Calculate the B and C axis solutions of the spindle program

[0043] According to the orientation of the processing feature, the corresponding spindle program front tool path is compiled. When the NC program is output through post-processing, the specific orientation of the spindle during the processing of the feature can be calculated, that is, the solution β4, β c5 , β c5 Calculated from β5 and the angular position of the machined feature in the XY coordinate system.

[0044] β5 represents the angle between the projection of the tool axis and the positive direction of the X-axis in the XY plane, which is given by Figure 1 , 2 The function curve can be obtained, and this position is the C-axis zero position of the processing feature, that is, when there is a same feature at this angular position, the C-axis rotation angle is 0 when processing the feature. Then, for any angular position C Ⅰ The characteristic of the spindle is the corresponding C-axis rotation angle β during spindle machining. c5 =β5-C Ⅰ . β c5 This is the value of SPC in the 3+2 coordinate system transformation instruction.

[0045] 2. Calculate the solution of B and C axes when using the angle head module for machining

[0046] Assume that the spindle is equipped with a 90° angle head with the tool facing the positive X direction. According to the angle α between the normal line of the feature and the XY plane, calculate the B and C axes γ4 and γ c5 , γ c5(1,2) By γ 5(1,2) and the angular position C of the feature in the XY coordinate system Ⅰ(1,2) Calculated: γ c5(1,2) =γ 5(1,2) -C Ⅰ(1,2) .

[0047] When α<45°, the B and C axes have two solutions, and the orientation of one solution is located in the positive half of the X axis (γ 4(1) , γ c5(1) ), the other solution is located in the negative half of the X axis (γ 4(2) , γ c5(2) ); When α = 45°, the two solutions coincide on the positive half axis of the Y axis, i.e., γ 4(1) =γ 4(2) , γ c5(1) =γ c5(2) .

[0048] Make γ through (0, 0) on the XY plane 5(1) , γ 5(2) The two rays in the angular direction are set as L1 and L2 respectively, and L1 is extended in the reverse direction as L1′.

[0049] 3. Calculate the range of interference interval in NC program

[0050] After the actual operation test of the equipment, the following two conclusions were drawn:

[0051] (i) The fan-shaped area between rays L2 and L1′ is the interval where the interference solution appears. That is, the characteristics of this area will be in the negative half of the X-axis (γ 4(2) , γ c5(2) ) position processing.

[0052] (ii) If the angular difference between the second feature and the first feature is less than 180°, then in one NC program the second feature will inherit the solution selected by the first feature for processing.

[0053] According to L2, L1′, that is, the B and C axis values ​​(γ 4(1) , γ c5(1) ), (γ 4(2) , γ c5(2) ), from the above C Ⅰ The formula for C can be obtained Ⅰ The two solutions C2 and C1′ can then calculate the specific range of the interference interval in the XY plane.

[0054] Then when the SPC value β of the NC program c5 ∈[C2,C1′], the program will select the solution of interference in the negative half of the X axis (γ 4(2) , γ c5(2) ).

[0055] Interference range, such as Figure 6 shown.

[0056] 4. Split the interference interval and set the exit rules

[0057] According to the previous method, calculate the corresponding C-axis angle C3 when the feature is located on the negative half axis of the X-axis. Use C3 as the dividing line to divide the interference interval into two half areas: [C2, C3], [C3, C1′].

[0058] Each interval is equal in size and symmetrical about the X-axis. Since L2 and L1′ are located in the negative half of the X-axis (it is impossible to cross the Y-axis to reach the positive half of the X-axis), the range of [C2, C1′] is less than 180°, and the range of each half is less than 90°.

[0059] According to the right-hand rule, when the feature is located in the [C2, C3] half area, if the SPC value is subtracted by 90°, it can jump out of the interference interval; when the feature is located in the [C3, C1′] half area, if the SPC value is added by 90°, it can also jump out of the interference interval.

[0060] However, it is not possible to change the processing position by directly changing the program SPC value. The specific change method requires the use of the test conclusion (II) in the previous article. A simple example is as follows:

[0061] If the NC program is in the interference interval and is located in the [C3, C1′] half area, the 3+2 coordinate system transformation statement in the NC program is as follows:

[0062] PLANE SPATIAL SPA+59SPB+43SPC+67TURN FMAX SEQ+TABLE ROT

[0063] Then, add two lines of statements before this line of statement: one is to rotate the feature out of the interference interval through coordinate transformation, and the other is to cancel the coordinate system transformation instruction. It is equivalent to adding an empty feature in the non-interference interval, and the angular difference with the real feature is less than 180°. In this way, when the real feature is processed, it will inherit the solution of the non-interference interval of the empty feature. The modified statement is as follows:

[0064] PLANE SPATIAL SPA+59SPB+43SPC+157TURN FMAX SEQ+TABLE ROT

[0065] PLANE RESET STAY

[0066] PLANE SPATIAL SPA+59SPB+43SPC+67TURN FMAX SEQ+TABLE ROT

[0067] 5. Set the angle head program trigger signal

[0068] The previous method gives two additional lines of output instructions, but when the program is output by post-processing, no matter whether the program is processed by the spindle head or the angle head, the processing method is the same. This is not acceptable. An additional trigger signal is required to tell the post-processing to output the above two lines of instructions only when the predecessor is an angle head program (because the program processed by the spindle head does not involve the problem of interference solution).

[0069] Take the 90° angle head processing with the tool installed on the spindle facing the positive direction of the X-axis (the same applies to the negative direction) as an example. By using the event HEAD that comes with the CAM software, the HEAD value is equal to angle_head_X and defined as the signal of the positive angle head of the X-axis. Once the post-processing detects the existence of this signal, the specified two lines of instructions are output when interference occurs. Otherwise, the output is based on the spindle head program without adding any additional instruction lines.

[0070] The specific implementation steps of the double-interference solution for the angle head processing of the five-axis machine tool with tilting head are as follows:

[0071] 1. Add the tcl statements corresponding to the algorithm of the present invention to NX post-processing;

[0072] 2. Add the HEAD event in the NX preamble file and give a trigger signal that matches the post-processing tcl statement;

[0073] 3. Select post-processing to output the NC program, and the specified command lines can be output to avoid the interference area.

[0074] The above-mentioned explanation process of the present invention is carried out using the Heidenhain system as an example. In fact, this method is also applicable to CNC systems with similar angle head algorithms: by adding specific signals in the post-processing, when the corresponding signal is given in the pre-processing, the post-processing will be processed according to the angle head program, and the interference interval will be calculated according to the angle of the feature, and then the instruction line that jumps out of the interference interval will be output, avoiding the interference solution and solving the interference problem in processing.

Claims

1. A method for solving the double-interference problem of the angle head of a five-axis machine tool with an inclined swing head, characterized in that: The following steps are involved: Step 1: Calculate the solution β4 of the B axis and the angle β5 between the projection line of the tool axis on the XY plane and the positive direction of the X axis when the spindle head NC program is output; Step 2: Calculate the solution β of the C axis when the spindle head NC program is output c5 ; Step 3: Calculate the solution of the B axis when the NC program is running in the angle head module mode 4(1) and γ 4(2) , the angle γ between the projection line of the tool axis on the XY plane and the positive direction of the X axis 5(1) and γ 5(2) ; Step 4: Calculate the solution of the C axis when the NC program is running in angle head module mode e5(1) and γ e5(2) ; Step 5: Calculate the interference interval of the machining feature when the NC program runs in the angle head module mode; Step 6: Split the interference interval; Step 7: Calculate the SPC value of each half area out of the interference interval; Step 8: Detect the trigger signal of the angle head program; when the signal is "N", the NC program does not use the angle head for processing and is directly output; when the signal is "Y", proceed to the next step; Step 9: Check whether the feature is in the interference area; when the signal is "N", the NC program will not select the interference solution processing and output it directly; when the signal is "Y", according to the half area where the feature is located, the program line of the solution to avoid interference is additionally output in the NC program.

2. According to claim 1, a method for processing double-interference in a five-axis machine tool angle head with a tilting head, characterized in that: β c5 =β5-C1; where C Ⅰ Any angular position.

3. A method for processing double-interference in a five-axis machine tool with an angle head of an inclined swing head according to claim 2, characterized in that: Assume that a 90° angle head with the tool facing the positive X direction is installed on the spindle. According to the angle α between the normal line of the feature and the XY plane, calculate the B and C axes γ in this case. 4、 γ c5 , γ c5(1,2) By γ 5(1,2) and the angular position C of the feature in the XY coordinate system Ⅰ(1,2) Calculated: γ c5(1,2) =γ 5(1,2) -C Ⅰ(1,2) ; When α<45°, the B and C axes have two solutions, and the orientation of one solution is located in the positive half of the X axis (γ 4(1)、 γ c5(1) ), the other solution is located in the negative half of the X axis (γ 4(2)、 γ c5(2) ); When α = 45°, the two solutions coincide on the positive half axis of the Y axis, i.e., γ 4(1) =γ 4(2)、 γ c5(1) =γ c5(2) .

4. A method for processing double-interference in a five-axis machine tool with an angle head of an inclined swing head according to claim 3, characterized in that: On the XY plane, make two rays through (0, 0) at angular directions of γ5(1) and γ5(2), set them as L1 and L2 respectively, and extend L1 in the opposite direction, set it as L1′; calculate C Ⅰ The two solutions C2 and C1′ of the NC program are used to calculate the specific range of the interference interval in the XY plane. When the SPC value of the NC program is βc5∈[C2,C1′], the program will select the solution of interference in the negative half of the X axis (γ 4(2) , γ c5(2) ).

5. A method for processing double-interference in a five-axis machine tool with an angle head of an inclined swing head according to claim 4, characterized in that: When the feature is located on the negative half axis of the X axis, the corresponding C axis angle C3 is calculated. Taking C3 as the dividing line, the interference interval is divided into two half areas: [C2, C3] and [C3, C1′].

6. A method for processing double-interference in a five-axis machine tool with an angle head of a tilting head according to claim 5, characterized in that: When the feature is located in the [C2, C3] half area, subtracting 90° from the SPC value can jump out of the interference interval; when the feature is located in the [C3, C1′] half area, adding 90° to the SPC value can jump out of the interference interval.

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