Simulation device

Abstract

To provide a simulation device capable of simulating movement of a panel after press molding.SOLUTION: A simulation device is configured in such a manner that a computer 10, on the basis of specification information including the mass of a panel 8 inputted to a press molding apparatus 2 by a user, a speed related value for the rising speed of an upper die 3, a value for the adsorption power of a magnetic force generating member 6, the mass of a panel advance presser pin 7, and a value for spring force, executes position calculation processing for calculating a bouncing amount and a compression amount of a spring 70, which are relative positions of an abutting surface 81 of the panel 8 to an adsorption surface 51 of a lifter 5, by prescribed period of time, the upper die 3 and the lifter 5 integrally rising from the state of having the panel 8 sandwiched by the upper die 3 and the lifter 5 by press molding, and the time when the lifter 5 only stops while the upper die 3 continuously rises being set as a starting point.SELECTED DRAWING: Figure 1

Description

[Technical field]

[0001] The present invention relates to a simulation device for simulating the state of a panel. [Background technology]

[0002] Some press molding devices are equipped with a panel advance pin that abuts against the panel before the upper die to position the panel, as described in, for example, JP 5-169147 A. The panel advance pin continues to press the panel downward until the stroke reaches its maximum value even when the upper die separates from the panel. In addition, as described in, for example, JP 2023-053824 A, a device that simulates the shape of the workpiece after press molding has also been developed. [Prior art documents] [Patent documents]

[0003] [Patent Document 1] Japanese Patent Application Publication No. 5-169147 [Patent Document 2] JP 2023-053824 A Summary of the Invention [Problem to be solved by the invention]

[0004] After press molding is completed and the upper die and the lifter are separated, the press-molded panel (workpiece) is transported to the next press molding device by a transport machine (e.g., a robot hand, etc.). The lifter constitutes at least a part of the lower die, and when the upper die rises after press molding, the lifter rises carrying the panel. In other words, after press molding, the upper die and the lifter rise together to a predetermined position where the transport machine can grasp the panel. Thereafter, the lifter stops, and only the upper die continues to rise, and the upper die and the lifter are separated. After they are separated, the transport machine grasps the panel and transports it to the next location. The productivity of the finished product is improved when the transport machine transports the panel smoothly (at high speed).

[0005] Here, when the upper mold and the lifter are separated (hereinafter sometimes abbreviated as "mold release"), the panel may be separated from the lifter due to inertial force. Even after the mold release and the panel advance holding pin and the panel are separated, the panel may still float from the lifter, and this phenomenon is called "panel dancing". When panel dancing occurs, it becomes difficult for the conveyor to grasp the panel until the panel dancing is resolved. In other words, the panel dancing becomes an obstacle to smooth conveyance (high-speed conveyance). Therefore, the panel is pressed against the lifter even after the mold release by the force of the panel advance holding pin and magnets, thereby suppressing the panel dancing. However, due to the configuration of a general-purpose mold, there are limitations on the pressing force of the panel advance holding pin, the stroke of the panel advance holding pin, and the attraction force of the magnet.

[0006] Furthermore, these force adjustments were performed by trial and error on the actual machine, such as by an operator actually replacing the spring of the panel advance pin. If it were possible to simulate the movement (position, state) of a panel after press forming, it would be possible to determine whether or not the panel will wobble without making adjustments to the actual machine. In other words, it would be possible to reduce the labor and work time required by an operator to make adjustments to the actual machine. An object of the present invention is to provide a simulation device capable of simulating the movement of a panel after press forming. [Means for solving the problem]

[0007] The simulation device of the present invention is a simulation device equipped with a computer that simulates the state of a panel for a press molding apparatus that includes an upper mold that moves up and down by a drive source, a lifter that constitutes at least a part of a lower mold, has an adsorption surface on its upper surface on which a panel is placed, and is arranged below the upper mold so that the adsorption surface abuts the abutment surface of the panel, and moves up and down by a drive source, a magnetic force generating member that attracts the panel to the adsorption surface by magnetic force, and a leading pressing member that protrudes downward from the upper mold while being biased by the spring force of a spring and is configured to be able to move up and down relative to the upper mold within a predetermined stroke range, presses the panel downward prior to the upper mold during press molding, and presses the panel within the predetermined stroke range even after the upper mold and the lifter are separated after press molding. The computer is configured to execute a position calculation process to calculate the amount of dance, which is the relative position of the contact surface of the panel relative to the attractive surface of the lifter, and the amount of compression of the spring, for each specified time period, starting from the point at which the upper mold and the lifter rise together from a state in which the panel is sandwiched between them by press molding, and the upper mold continues to rise until only the lifter stops, based on specification information input by a user, including the mass of the panel, a speed-related value related to the rising speed of the upper mold, a value related to the adhesive force of the magnetic force generating member, the mass of the advance holding member, and a value related to the spring force. Effect of the Invention

[0008] According to the present invention, the amount of panel movement and the amount of spring compression are calculated for each predetermined time from the starting point. This makes it possible to simulate the movement of the panel after press forming. By simply inputting various information about the press forming device, the user can determine whether or not there is "panel movement," in which the panel moves away from the lifter after the advance holding member moves away from the panel (i.e., after the amount of compression of the spring reaches a minimum value). According to the present invention, the presence or absence of panel movement can be easily determined by simply changing the input values ​​to the computer, without changing the configuration of the press forming device (actual machine). [Brief description of the drawings]

[0009] [Figure 1] FIG. 2 is a conceptual diagram of a simulation device and a press forming device according to the present embodiment. [Diagram 2] FIG. 1 is a conceptual diagram of a press molding apparatus according to an embodiment of the present invention. [Diagram 3] FIG. 2 is a conceptual plan view (reference example) of a lower mold of the present embodiment. [Figure 4] FIG. 4 is a conceptual diagram of a graph created by the simulation device of the present embodiment. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0010] A simulation device 1, which is one embodiment of the present invention, will be described in detail below with reference to the drawings as a mode for carrying out the present invention. In addition to the following examples, the present invention can be carried out in various forms with various modifications and improvements based on the knowledge of those skilled in the art. Also, the components of the press molding device 2 in the drawings (e.g., the shape of the upper die, lifter, and panel, etc.) are conceptual diagrams for explanatory purposes and differ from the actual shapes.

[0011] As shown in Fig. 1, the simulation device 1 of this embodiment includes a computer 10. The computer 10 includes one or more processors and one or more memories. In addition, the computer 10 is connected to an input means 10a such as a keyboard or a mouse, and a display means 10b such as a display. A calculation program (e.g., a spreadsheet software, etc.) designed to execute various calculations (e.g., position calculation processing, which will be described later) is installed in the computer 10.

[0012] The apparatus to be simulated by the simulation device 1 is a press forming apparatus 2. The press forming apparatus 2 is equipped with an upper die 3, a lifter 5, a magnetic force generating member 6, and a panel advance holding pin (corresponding to an "advance holding member") 7. The upper die 3 is a member (which can also be called an upper die unit) that moves up and down by a driving source 21, and is composed of, for example, a die, a pad, or a combination thereof. The upper die 3 can be called a member that sandwiches a panel 8 with the lifter 5 in press forming. The panel 8 is a plate-shaped workpiece (object to be pressed) made of metal (magnetic material), and is also called a workpiece.

[0013] The lifter 5 is a device that transports the panel 8 upward, and is configured to be movable up and down. The lifter 5 constitutes at least a part of the lower mold, and is arranged opposite the upper mold 3. In this embodiment, at least in the cross-sectional positions of Figs. 1 and 2, the lifter 5 also functions as the lower mold. The lifter 5 has an adsorption surface 51 on its upper surface on which the panel 8 is placed. The lifter 5 is arranged below the upper mold 3 so that the adsorption surface 51 abuts against the abutment surface 81 of the panel 8. The lifter 5 is moved up and down by a driving source 22. Each driving source 21, 22 is configured to include, for example, a spring, a fluid cylinder, or an electric motor.

[0014] The magnetic force generating member 6 is configured to attract the panel 8 to the attraction surface 51 by magnetic force. The magnetic force generating member 6 in this embodiment constitutes the attraction surface 51. The magnetic force generating member 6 in this embodiment is a magnet. In this embodiment, the contact surface 81 is provided at both left and right end portions (lower end portions) of the panel 8 formed in a substantially U-shape. The attraction surface 51 is provided at a portion of the upper surface of the lifter 5 that faces the contact surface 81 in the up-down direction. For example, one or more magnets (magnetic force generating members 6) are disposed in each recess provided in a portion of the lifter 5 that corresponds to the attraction surface 51. Each attraction surface 51 is constituted by a magnet (magnetic force generating member 6) fixed to the lifter 5. Before press molding, the panel 8 is disposed on the lifter 5 so that the contact surface 81 and the attraction surface 51 come into contact with each other. The contact surface 81 and the attraction surface 51 come into contact with each other before press molding, or come into contact with each other immediately after press molding. The magnetic force generating member 6 is not limited to a magnet, and may be one capable of adjusting the magnetic force according to the amount of power supplied.

[0015] The panel advance hold-down pin 7 protrudes downward from the upper die 3 while being biased by the spring force of a spring 70, and is configured to be movable up and down within a predetermined stroke range relative to the upper die 3. During press molding, the panel advance hold-down pin 7 comes into contact with the panel 8 prior to the upper die 3, and presses the panel 8 downward. The panel advance hold-down pin 7 positions the panel 8. After coming into contact with the panel 8, the panel advance hold-down pin 7 is accommodated within the upper die 3 as the upper die 3 descends. The panel advance hold-down pin 7 presses the panel 8 within a predetermined stroke range (within a movable range) even after the upper die 3 and the lifter 5 are separated after press molding. The tip surface of the panel advance hold-down pin 7 forms part of the press surface (lower surface) of the upper die 3.

[0016] The panel prior hold down pin 7 is formed in a pin shape. The panel prior hold down pin 7 is arranged in a recess 31 formed in the upper die 3 so as to be movable up and down. A spring 70 that urges the panel prior hold down pin 7 downward is arranged in the recess 31. The recess 31 is formed to completely accommodate the panel prior hold down pin 7. The initial state (state before press molding) is when the tip face of the panel prior hold down pin 7 is located at the lowest position relative to the upper die 3, and the accommodated state is when the tip face of the panel prior hold down pin 7 is flush with the lower surface (machined surface) of the upper die 3. In the initial state, the spring 70 is slightly compressed (initial compression amount ≠ 0).

[0017] The tip surface of the panel advance hold pin 7 descends with the descending of the upper mold 3, comes into contact with the panel 8, and is accommodated in the recess 31 as the upper mold 3 descends while pressing the panel 8. When the upper mold 3 is located at the bottom dead center, the panel advance hold pin 7 is accommodated. When the upper mold 3 ascends relative to the lifter 5, the panel advance hold pin 7 protrudes downward while pressing the panel 8 as the upper mold 3 ascends until it reaches its initial state. The predetermined stroke can be said to be the protrusion amount of the tip surface of the panel advance hold pin 7 in the initial state. The protrusion amount of the panel advance hold pin 7 corresponds to the compression amount of the spring 70 (negative correlation). Calculating the compression amount of the spring corresponds to calculating the protrusion amount of the panel advance hold pin 7. The panel advance hold pin 7, the spring 70, and the recess 31 can be said to be one advance hold unit. The advance hold member may not be the panel advance hold pin 7, but may be a mold (a divided advance hold mold) that constitutes a part of the upper mold 3. As the press forming device 2, a known general-purpose device can be used.

[0018] Press molding is performed, for example, by a control device of the press molding device 2 as follows. The upper mold 3 descends toward the lifter 5 (lower mold) on which the panel 8 (for example, a U-shaped panel) is placed, and the panel 8 is sandwiched between the upper mold 3 and the lifter 5. Thereafter, the lifter 5 follows the upward movement of the upper mold 3 (for example, the lifter 5 is biased upward by a spring), and the upper mold 3 and the lifter 5 rise together to a predetermined position (a position corresponding to gripping by the conveyor). That is, the upper mold 3 and the lifter 5 rise at the same speed to a predetermined position. The lifter 5 lifts the panel 8, and a gap is formed between the lifter 5 and the lower mold adjacent to the back or front side of FIG. 1 (front or rear of FIG. 3) and the panel 8. This allows the conveyor to grip the panel 8. When the lifter 5 reaches the predetermined position, it stops rising (starting point), and the upper mold 3 continues to rise even after reaching the predetermined position. As a result, the upper die 3 and the panel 8 separate from each other, and as the distance between them increases, the panel advance holding pin 7 protrudes downward within a predetermined stroke range. After the panel advance holding pin 7 and the panel 8 separate from each other by lifting only the upper die 3, the conveyor grasps the panel 8 from the side and conveys it to a predetermined location (for example, the next press molding device).

[0019] In the above operation, when the lifter 5, which had been rising, stops at a predetermined position, the panel 8 tries to continue rising due to the force of inertia. Even after the panel 8 has been separated from the upper mold 3, it is subjected to a force (downward force) toward the lifter 5 due to the pressing force of the panel leading hold down pin 7 and the attraction force (magnetic force) of the magnetic force generating member 6. When the force of inertia exceeds this force, the panel 8 separates from the lifter 5, as shown in Figure 2. If the panel 8 and the lifter 5 separate after the panel leading hold down pin 7 and the panel 8 separate (this phenomenon is called "panel dance"), it becomes difficult for the conveyor to immediately grasp the panel 8, making high-speed conveyance difficult.

[0020] (Position calculation processing) The computer 10 is configured to execute a position calculation process based on specification information including "mass of the panel 8," "speed-related value related to the rising speed of the upper die 3," "value related to the attraction force of the magnetic force generating member 6," "mass of the panel leading hold-down pin 7," and "value related to the spring force" input by the user. The position calculation process is a process of calculating "the amount of movement, which is the relative position of the contact surface 81 of the panel 8 with respect to the attraction surface 51 of the lifter 5," and "the amount of compression of the spring 70" for each predetermined time period, starting from the time when the upper die 3 and the lifter 5 rise together from a state in which the panel 8 is sandwiched between them by press molding, and only the lifter 5 stops. The position calculation process can also be said to be a process of calculating the position of the contact surface 81, the position of the attraction surface 51, and the position of the tip of the panel leading hold-down pin 7.

[0021] In the position calculation process, computer 10 sets the starting point as n=0 and calculates the amount of movement of panel 8 (the amount of movement = 0 when n=0) and the amount of compression of spring 70 (the amount of compression is maximum when n=0) at time point n (n is an integer equal to or greater than 0) by increasing n in sequence from 0 (n=0, 1, 2, 3, ...). Time point n+1 is a predetermined time after time point n. Computer 10 calculates the amount of movement and the amount of compression at each time point for each predetermined time. Computer 10 executes the position calculation process in sequence until n becomes a predetermined integer from 0. In other words, computer 10 simulates the movement (state) of panel 8 during the period from the starting point to the predetermined set time.

[0022] Based on the specification information input by the user, the computer 10 calculates the panel acting forces F1, including "gravity F1 acting on the panel 8," "gravity F2 of the panel leading presser pin 7 acting on the panel 8," "spring force F3 of the panel leading presser pin 7 acting on the panel 8," and "adsorption force (magnetic force) F4 of the magnetic force generating member 6" at the time point n. p Calculate the following.

[0023] The computer 10 calculates the panel acting force F by using the following equations (1) to (5) based on the equation of motion. pwhere g is the gravitational acceleration, m is the mass of the panel 8, M is the mass of the panel advance pin 7, and k s is the spring constant (total spring constant), and δ s is the compression amount (spring deflection amount) of the spring 70, and δ m is the distance (gap) between the suction surface 51 and the contact surface 81, that is, the amount of movement of the panel 8. F1 = m × g (1) F2 = M × g (2) F3=k s ×δ s ...(3) F4 = f(δ m ) (4) F p =F1+F2+F3+F4 (5) A p =g+(M×g) / m+(k s ×δ s ) / m+f(δ m ) / m ····(6)

[0024] The computer 10 calculates the panel acting force F as shown in the above formula (6). p By dividing by the mass m of panel 8, we get the acceleration A of panel 8. p The computer 10 calculates the acceleration A of the panel 8. p By integrating with time, we obtain the velocity V of panel 8. p The computer 10 calculates the velocity V of the panel 8. p By integrating the above with respect to time, the position P of panel 8 is obtained. p The computer 10 calculates the acceleration A of the panel 8. p By integrating twice, we obtain the position P of panel 8. p It can be said that the above equation is calculated.

[0025] After the starting point (n=0, time t=0), the upper die 3 actually rises and the lifter 5 stops, but in the calculation it is assumed that the upper die 3 stops and the lifter 5 moves. In other words, in the calculation, the lifter 5 moves downward relative to the upper die 3 after the starting point. The descent speed V of the lifter 5 lis the rising speed V of the upper die 3 u Corresponding to (V l =-V u Therefore, the position P of the suction surface 51 of the lifter 5 l is the descent speed V l and the elapsed time from the starting point.

[0026] The amount of movement δ, which is the relative position of the contact surface 81 with respect to the suction surface 51 m is the position P of lifter 5 l and position P of panel 8 p In other words, it is the distance between the suction surface 51 and the contact surface 81. l and position P of panel 8 p Based on this, the amount of dance δ m When the panel 8 is in contact with the lifter 5, the amount of movement δ m will be 0.

[0027] At the origin (n=0, time t=0), δ m is 0. In the above calculation, the computer 10 calculates δ m = 0, and the acceleration A of panel 8 p Calculate the position P of panel 8. p At this time, the position P of the lifter 5 is calculated. l is the position P of panel 8 p The descent speed of lifter 5 is V l Based on the speed-related value, the position P of the lifter 5 l Calculate the position P of lifter 5. l The compression amount of the spring 70 is calculated based on the compression amount δ of the spring 70. s is a predetermined maximum value at the starting point, and decreases according to the movement (position) of the lifter 5 or the panel 8.

[0028] In the calculation, the gravity F1 acting on the panel 8 is constant. The gravity F2 of the panel leading hold-down pin 7 is constant when the panel leading hold-down pin 7 and the panel 8 are in contact with each other, and becomes 0 when they are separated. The spring force F3 becomes smaller as the upper die 3 rises (as the upper die 3 and the panel 8 separate from each other), and becomes 0 when the panel leading hold-down pin 7 and the panel 8 are separated from each other. The suction force F4 is calculated by applying δ to an approximate formula (e.g., a graph) previously set by experiments, etc., by the computer 10. m The approximation formula is δ m The larger F4 is, the smaller F4 becomes (for example, F4 is δ m F4 is set to be inversely proportional to the second line of δ m The computer 10 calculates the amount of dance δ at time n. m Based on this, the amount of dance at time point n+1, a predetermined time after time point n, is calculated as δ m and the compression amount δ s Calculate the following.

[0029] In this way, the computer 10 calculates the dance amount δ at each point n from n=0 to n=N (a predetermined integer) according to the calculation program. m and the compression amount δ s The computer 10 calculates the amount of dance δ with respect to the time lapse from the starting point in response to the user's operation or the calculation program. m and the compression amount δ s In more detail, as shown in FIG. 4, the computer 10 calculates the dance amount δ at each time point n in response to a user's operation or a calculation program. m , compression amount δ s , position P of panel 8 p , and the position P of the lifter 5 l 4, the horizontal axis represents time (from n=0 to n=N) and the vertical axis represents position or amount. The computer 10 may automatically create the graph in accordance with a calculation program.

[0030] One of the criteria for determining that panel dancing does not occur is that "the amount of dancing is less than a predetermined threshold value." Another of the criteria is that "the amount of dancing converges, although the amount of dancing is not equal to 0." Another of the criteria is that "the amount of dancing converges within a predetermined threshold time from the starting point." Another of the criteria is that "the amount of dancing converges before the amount of compression of the spring 70 reaches the minimum value (initial compression amount)." The computer 10 or the user, for example, determines whether or not one or more of these criteria (preferably all of the criteria) are met from the calculation result, and determines whether or not panel dancing occurs. When a user determines whether or not panel dancing occurs, the user can easily make the determination by being able to refer to a graph such as that shown in FIG. 4. In the graph of FIG. 4, the amount of dancing converges before the amount of compression of the spring 70 reaches the minimum value, so it can be determined that panel dancing does not occur. The content, number, and combination of the criteria can be set as appropriate.

[0031] The user inputs the spring constant k s , an approximate formula for the attraction force F4 (number and type of magnets), or the rising speed V of the upper die 3 u By changing the settings, it is possible to judge whether or not panel vibration will occur in the changed configuration. Since the user can change the configuration (conditions) of an existing (general-purpose) press forming device that can be changed relatively easily in a simulation rather than on an actual device, the user can easily find an appropriate configuration.

[0032] In this way, according to the present embodiment, the amount of movement δ of the panel 8 for each predetermined time from the starting point m and the compression amount δ of spring 70 s is calculated. This makes it possible to simulate the movement (position, state) of the panel 8 after press molding. By simply inputting various information of the press molding device 2, the user can calculate the amount of compression δ of the spring 70 after the panel advance holding pin 7 separates from the panel 8 (i.e., sIt is possible to determine the presence or absence of "panel bouncing" in which the panel 8 separates from the lifter 5 after the panel 8 reaches a minimum value. According to this embodiment, the presence or absence of panel bouncing can be easily determined by simply changing the input values ​​to the computer 10 without changing the configuration of the press forming apparatus 2 (actual machine).

[0033] The lifter 5 may be formed so as to protrude upward from a recess formed in the lower die by the force of a spring, as in the structural relationship between the upper die 3 and the panel advance holding pin 7 (configuration in which the upper and lower dies are inverted). The lifter 5 is biased upward by a spring, and the compression amount of the spring reaches a maximum immediately after press forming, and the lifter protrudes upward with the panel 8 still placed thereon as the upper die 3 separates from the lower die. Even in such a configuration, the simulation device 1 can be applied. Also, even in such a configuration, it can be said that the lifter 5 constitutes a part of the lower die. A unit including the lifter and the lower die can be said to be a lower die unit. Also, the upper die 3 (upper die unit) may be configured, for example, by arranging a pad in the center and arranging upper die main body members or upper die steel materials on the left and right of the pad. The upper die 3 can be said to be an upper die unit formed of multiple members, and the lower die can be said to be a lower die unit formed of multiple members. [Explanation of symbols]

[0034] 1...simulation device, 10...computer, 2...press molding device, 21, 22...driving source, 3...upper mold, 5...lifter, 51...adsorption surface, 6...magnetic force generating member, 7...panel advance holding pin (advance holding member), 8...panel, 81...contact surface.

Claims

1. An upper die that moves up and down by a drive source; a lifter that constitutes at least a part of a lower mold, has an adsorption surface on an upper surface on which a panel is placed, is disposed below the upper mold so that the adsorption surface abuts against an abutment surface of the panel, and is moved up and down by a drive source; a magnetic force generating member that attracts the panel to the attraction surface by magnetic force; a leading pressing member that protrudes downward from the upper die while being biased by the spring force of a spring and is configured to be vertically movable within a predetermined stroke range relative to the upper die, pressing the panel downward prior to the upper die during press molding, and pressing the panel within the predetermined stroke range even after the upper die and the lifter are separated from each other after press molding; A simulation device comprising a computer that simulates a state of the panel for a press forming device comprising: The computer includes: based on specification information input by a user, the specification information including a mass of the panel, a speed-related value related to a rising speed of the upper mold, a value related to an attractive force of the magnetic force generating member, a mass of the preceding pressing member, and a value related to the spring force, The upper die and the lifter rise together from a state in which the panel is sandwiched between them by press molding, and the upper die continues to rise until only the lifter stops. A position calculation process is then executed to calculate the amount of bounce, which is the relative position of the contact surface of the panel with respect to the suction surface of the lifter, and the amount of compression of the spring, for each predetermined time. Simulation device.

2. In the position calculation process, the computer The starting point is set to n=0, and the dance amount (when n=0, the dance amount is 0) and the compression amount (when n=0, the compression amount is maximum) at time point n (n is an integer equal to or greater than 0) are calculated by increasing n in order from 0, The computer includes: calculating panel action forces at time n based on the specification information, the panel action forces including the gravity acting on the panel, the gravity of the preceding presser member acting on the panel, the spring force of the preceding presser member acting on the panel, and the adsorptive force of the magnetic force generating member; Calculating an acceleration of the panel based on the panel acting force; Calculating a position of the panel based on the acceleration of the panel; Calculating the amount of dancing based on the position of the panel; Calculating the compression amount based on the speed-related value; The computer includes: Calculating the amount of flutter and the amount of compression at time point n+1, which is a predetermined time after time point n, based on the amount of flutter at time point n; The position calculation process is executed in order from 0 to a predetermined integer number n. The simulation device according to claim 1 .

3. The computer creates a graph showing the amount of dance and the amount of compression over time from the starting point in response to a user's operation or a calculation program. The simulation device according to claim 1 or 2.

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