Mobile mold changing device and leveling method

Abstract

The present invention provides a mobile mold changing device that suppresses tilting of the device caused by uneven floor surfaces and load fluctuations, thereby enabling highly accurate mold changes. [Solution] A mobile mold changing device X for loading or unloading molds M between and a connection target J, comprising: a movable vehicle body 1 having a mounting surface F on which to place the mold M; a plurality of casters 2 supporting the vehicle body 1; an electrically operated height adjustment mechanism 3 capable of individually adjusting the support height h of at least one of the plurality of casters 2; a lifting device 4 for raising and lowering the mounting surface F; and a leveling means 300 that drives the height adjustment mechanism 3 and generates a signal to correct the inclination of the vehicle body 1, wherein the leveling means 300 generates a control signal that adjusts the lifting direction of the lifting device 4 to a substantially vertical direction by making the mounting surface F substantially horizontal based on the drive of the height adjustment mechanism 3.

Description

Technical Field

[0001] The present invention relates to a mobile mold-changing device for changing molds used in injection molding machines, press molding machines, die-casting molding machines, etc.

Background Art

[0002] In an injection molding factory, it is necessary to change the mold of the molding machine according to the production plan. At this time, mobile mold-changing devices such as automated guided vehicles (AGVs), autonomous mobile robots (AMRs), and electric lifters are used. These have a lifting mechanism and perform the transfer of the mold after precisely positioning it with respect to the molding machine.

[0003] Here, the installation accuracy of the mold directly affects the combination accuracy of the molds. Even a slight misalignment causes a deviation in the mold combination, which is a direct cause of molding defects such as burrs and dimensional abnormalities. Also, when clamping the mold in this state, an uneven load acts, which is also a factor that impairs the life of the mold and the molding machine. In addition, if an installation defect is found in a subsequent process, the production efficiency is significantly reduced due to rework.

[0004] However, in a mobile mold-changing device, static inclination due to unevenness or inclination of the floor surface, etc., and dynamic inclination accompanying load fluctuations of the mold are inevitable. These affect the posture of the lifting mechanism and are factors that disrupt the vertical movement of the mold.

[0005] As a technology related to the above, conventionally, a horizontal correction technology using an outrigger method used in a vehicle with a crane, etc. is known, but this method cannot be applied to the high-precision positioning required for mold change, and is accompanied by problems such as misalignment, load on the connection part, and safety. Also, a posture correction technology for only the loading platform and a positioning technology in the horizontal plane have been proposed, but they do not eliminate the inclination of the vehicle body itself.

Prior Art Documents

Patent Documents

[0006] [Patent Document 1] Japanese Patent Application Publication No. 11-291912 [Patent Document 2] Patent No. 7541415 [Overview of the Initiative] [Problems that the invention aims to solve]

[0007] In view of the present invention, the objective is to provide a mobile mold changing device and a leveling method that suppress tilting of the device caused by unevenness of the floor surface or load fluctuations, and realize highly accurate mold changing. [Means for solving the problem]

[0008] To solve the above problems, the mobile mold changing device according to this disclosure is A mobile mold changing device that loads or unloads molds between and to a connected object, The invention comprises a movable vehicle body having a mounting surface for placing a mold, a plurality of casters supporting the vehicle body, an electrically operated height adjustment mechanism capable of individually adjusting the support height of at least one of the plurality of casters, a lifting device for raising and lowering the aforementioned mounting surface, and a leveling means that drives the height adjustment mechanism to generate a signal for correcting the tilt of the vehicle body, The leveling means generates a control signal that adjusts the lifting direction of the lifting device to a substantially vertical direction by making the aforementioned mounting surface substantially horizontal based on the drive of the height adjustment mechanism.

[0009] Furthermore, the leveling method relating to this disclosure is A method for leveling the aforementioned mounting surface in a mobile mold changing device that performs loading or unloading of molds between a connected object, comprising: a movable vehicle having a mounting surface for mounting a mold; a plurality of casters supporting the vehicle; an electrically operated height adjustment mechanism capable of individually adjusting the support height of at least one of the plurality of casters; and a lifting device for raising and lowering the aforementioned mounting surface, the device. The steps include generating a control signal based on the tilt of the vehicle body, The method includes the step of driving the height adjustment mechanism based on the control signal and adjusting the lifting direction of the lifting device to be approximately vertical by making the aforementioned mounting surface approximately horizontal. [Effects of the Invention]

[0010] According to the present invention, it is possible to provide a mobile mold changing device and a leveling method that suppress tilting of the device caused by unevenness of the floor surface or load fluctuations, thereby enabling highly accurate mold changing. [Brief explanation of the drawing]

[0011] [Figure 1] A diagram showing the mobile mold changing device of this embodiment, (a) a schematic perspective view, (b) a bottom view, and (c) an enlarged side view. [Figure 2] A diagram illustrating the configuration of the control device according to this embodiment. [Figure 3] A diagram showing the caster and height adjustment mechanism of this embodiment, (a), (b) schematic perspective view, and (c) bottom view along line PP'. [Figure 4] An explanatory diagram of the operation of the height adjustment mechanism of this embodiment. [Figure 5] A schematic diagram of the mold exchange system of this embodiment. [Figure 6] A schematic diagram of the mold exchange system of this embodiment. [Figure 7] A schematic diagram of the mold exchange system of this embodiment. [Figure 8] A processing flowchart for the leveling method of this embodiment. [Figure 9] A processing flowchart for the static leveling method of this embodiment. [Figure 10] A processing flowchart for the dynamic leveling method of this embodiment. [Modes for carrying out the invention]

[0012] Hereinafter, with reference to the drawings, a mobile mold changing device, a mold changing system, and a leveling method according to an embodiment of the present invention will be described. Note that the following embodiments are examples of the present invention, and the present invention is not limited to the following embodiments. Also, in these drawings, reference numeral X indicates the mobile mold changing device according to the present embodiment, and reference numeral S indicates the mold changing system according to the present embodiment.

[0013] In the present embodiment, the configuration, operation, etc. of the mold changing system and the mobile mold changing device will be described. However, a control method having a similar configuration, a computer program, and a program recording medium recording the program also have the same effects. By using the program recording medium, for example, the program can be installed in a computer. A series of processes according to the present embodiment described below is provided as a program executable by a computer, and can be provided via a non-transitory computer-readable recording medium such as a CD-ROM or a flexible disk, and further via a communication line.

[0014] Hereinafter, for convenience of explanation, the x-axis direction in FIG. 1 and the like will be referred to as the left-right direction, the y-axis direction as the front-rear direction, and the z-axis direction as the up-down direction, respectively.

[0015] <Device Configuration> Hereinafter, with reference to FIGS. 1 to 4, the configuration of the mobile mold changing device X (hereinafter simply referred to as the device X) will be described.

[0016] <<Schematic Configuration of the Outside and Inside of the Device>> As shown in FIG. 1, the device X is for carrying in or out the mold M (see FIG. 7) to and from the connection target J (see FIG. 5 and the like), and includes a movable vehicle body 1 having a placement surface F for placing the mold M, three casters 2 for supporting the vehicle body 1, an electric height adjustment mechanism 3 capable of individually adjusting the support height h (see FIG. 4) of each caster 2, and a lifting device 4 for raising and lowering the placement surface F.

[0017] The vehicle body 1 is an autonomously roaming unmanned transport vehicle and includes a base section 11, a top section 12, a support column section 13 connecting the base section 11 and the top section 12, a sliding section 14 on which the lifting device 4 is mounted, and a mold mounting section 15 mounted on the lifting device 4, which has a mounting surface F. Furthermore, the vehicle body 1 has a highly rigid frame structure to stably support the load of the mold M, and is configured so that the support reaction force on the multiple casters 2 is uniformly transmitted to the entire vehicle body 1. Note that the joint p, which will be described later, is not shown in Figure 1.

[0018] The base portion 11 is a roughly rectangular parallelepiped housing, and as shown in Figure 1(b), it contains a space inside which each caster 2 and the corresponding height adjustment mechanism 3 are housed. Furthermore, the base section 11 houses the control device 200, which will be described later, and the wiring to the casters 2, tilt sensors 210, load cells 220, etc., is connected internally.

[0019] As shown in Figure 1(b), each caster 2 is attached to the base 11 such that two casters 2 are positioned on the front side and one caster 2 is positioned on the rear side. This three-point support configuration stabilizes the posture of the vehicle body 1, ensuring that the correction amount by the height adjustment mechanism 3 during leveling is reliably reflected in the vehicle body posture. Furthermore, since the mold M is brought in from the front, this configuration also contributes to improving the stability of the vehicle body 1's posture during this process.

[0020] The top surface portion 12 is a thin, roughly rectangular plate-like body, and a marker (not shown) such as a QR code (registered trademark) for position recognition, used for recognition by an external management device L or a connected target J, is placed on its upper surface.

[0021] The support columns 13 are elongated rod-shaped bodies that extend vertically from the four corners of the base 11 and the top surface 12, thereby creating a space in which a lifting device 4 or the like can be installed.

[0022] The sliding part 14 is provided on the upper surface of the base part 11, and the lifting device 4 is configured to be electrically slidable by rails r that extend in the left-right direction, thereby improving the alignment accuracy of the mounting surface F with respect to the connection target J.

[0023] In this embodiment, the mold mounting section 15 is provided in pairs adjacent to each other in the left-right direction, and each is equipped with a plurality of rollers k that extend in the left-right direction at predetermined intervals along the front-rear direction. This roller k is designed to reduce the resistance to movement when loading and unloading the mold M, and to allow the mold M to move smoothly in the forward and backward directions. Furthermore, the mounting surface F in this embodiment is a virtual plane on which the tops of each roller k, excluding the foremost roller k, are positioned in a side view, as shown by the dashed line in Figure 1(c).

[0024] Each caster 2 is a support mechanism that supports the device X so that it can move on the floor surface, and is configured to allow adjustment of the orientation of the mounting surface F by the height adjustment mechanism 3. The configuration of each caster 2 and the corresponding height adjustment mechanism 3 will be described in detail using Figures 3 and 4.

[0025] The lifting device 4 is a lifting mechanism for moving the mounting surface F in the vertical direction, and includes, for example, an electrically operated lifting mechanism that transmits the rotation of a motor to a lifting shaft to displace the mounting surface F in the vertical direction. Specifically, a plurality of lifting columns are provided as a lifting shaft, extending in the vertical direction, and these lifting columns are supported by screw mechanisms such as a ball screw mechanism or a trapezoidal screw mechanism, and the lifting columns are displaced in the vertical direction in accordance with the rotation of the screw shaft accompanying the drive of the motor. Furthermore, a bellows-shaped protective member (bellows cover) that expands and contracts in accordance with the vertical movement of the lifting column is provided on the outer circumference of the lifting column, preventing foreign objects from entering the lifting column and ensuring the safety of workers. Furthermore, the lifting device 4 is not limited to an electrically operated configuration using these screw mechanisms; to handle heavy loads, a hydraulic lifting mechanism using a hydraulic cylinder or a mechanism that performs lifting operations via a link mechanism may also be employed.

[0026] The control device 200 shown in Figure 2 is an electronic control unit for controlling various sensors and drive systems of device X, and includes a processor 201, memory 202, communication interface 203, tilt sensor 210, load cell 220, height adjustment mechanism drive unit 230, etc.

[0027] The processor 201 is an arithmetic processing unit that executes programs stored in memory 202 to perform various control processes, including static leveling and dynamic leveling, which will be described later. The processor 201 functions as a leveling start condition determination unit that executes the leveling start condition determination step S101 (described later), a correction amount determination unit that executes the correction amount determination step S102, a height adjustment mechanism drive unit that executes the height adjustment mechanism drive step S103, and a leveling completion determination unit that executes the leveling completion determination step S104, by executing a program stored in the memory 202. Inside the processor 201, a leveling means 300 is configured as a functional block. Based on detection information obtained from the tilt sensor 210 and load cell 220, it calculates the attitude error of the vehicle body 1 and performs processing to determine the correction amount of the height adjustment mechanism 3 for each caster 2.

[0028] Memory 202 is a non-volatile or volatile storage area that stores control programs executed by the processor 201, adjustment amount data, information regarding the support height h of the caster 2, and information related to the position and orientation of the vehicle body 1.

[0029] The communication interface 203 is a communication port for sending and receiving location information, operation commands, synchronization signals, etc., between an external management device and a molding machine-side device, and may consist of wired communication, wireless communication, or a combination thereof.

[0030] The tilt sensor 210 is an inclinometer attached to the vehicle body 1, which detects the tilt of the vehicle body 1 in the roll direction and pitch direction, and the detected values ​​are input to the leveling means 300.

[0031] The load cell 220 is a load sensor located on each caster 2, and it detects the load acting on each caster 2. The values ​​detected by the load cell 220 are input to the leveling means 300 in order to estimate the attitude changes of the vehicle body 1 and the elastic deformation of each caster 2.

[0032] The height adjustment mechanism drive unit 230 is a drive circuit and drive motor controller that drives the height adjustment mechanism 3 of each caster 2 to adjust the support height h based on a command from the processor 201. The correction amount determined by the leveling means 300 is supplied to the height adjustment mechanism drive unit 230, and the height of each caster 2 is adjusted so that the orientation of the mounting surface F becomes approximately horizontal.

[0033] With the control device 200 configured in this way, various leveling processes such as static leveling and dynamic leveling, which will be described later, are realized, and the posture of the vehicle body 1 is appropriately maintained when the mold is changed.

[0034] <<Configuration of casters and height adjustment mechanism>>

[0035] The configuration of the caster 2 and the height adjustment mechanism 3 will be described in detail below using Figures 3 and 4. Note that the steering mechanism W, which will be described later, is not shown in Figures 3(c) and 4. Furthermore, in Figures 3(c) and 4, the wheels 21 and drive motor 31a, which will be described later, are not shown in cross-section.

[0036] As shown in Figure 3, the caster 2 includes a wheel (caster wheel) 21, a caster bracket 22, and a steering mechanism W. In this embodiment, the caster 2 refers to the "main support wheel" that primarily supports the load of the vehicle body 1 and participates in attitude control depending on its support height, as described above. For this reason, auxiliary wheels (such as stabilizers) used for purposes such as preventing tipping may be provided on the vehicle body 1, one or more of them, but these are not included in the caster 2.

[0037] The wheel 21 is a wheel configured to roll on the floor surface and is rotatably supported by the caster bracket 22.

[0038] The caster bracket 22 is a support frame that supports the wheel 21 and stably holds the wheel 21 by receiving support force from the height adjustment mechanism 3. Furthermore, the caster bracket 22 is provided with a stopper portion t to prevent it from detaching from the nut support portion 33, which will be described later.

[0039] The steering mechanism W is a pivot drive mechanism for pivoting the caster 2 around a vertical axis, and includes a steering motor W1, a small gear W2, a large gear W3, a pivot angle sensor W4 for detecting the pivot angle of the caster 2, a sensor bracket W5 for attaching the pivot angle sensor W4 to the caster bracket 22, and a proximity sensor W6 for regulating the steering rotation range and setting the origin.

[0040] The rotation of the steering motor W1 is transmitted to the large gear W3 via the small gear W2, and together with the large gear W3, the entire caster 2 rotates around the vertical axis. The swivel angle sensor W4 is an angle detector that detects the actual swivel angle of the caster 2 and feeds it back to the control device 200.

[0041] As shown in Figure 3, the height adjustment mechanism 3 includes a ball screw mechanism 31, a motor support part 32, a nut support part 33, a bearing part 34, a spacer 35, and a fastening bolt 36.

[0042] The ball screw mechanism 31 comprises a drive motor 31a, a screw shaft portion 31b, and a nut portion 31c. When the screw shaft portion 31b is rotated by the drive motor 31a, the nut portion 31c moves vertically, and the support height h of the caster 2 is adjusted.

[0043] The drive motor 31a is an electric motor for rotationally driving the screw shaft portion 31b, and is fixedly held in place by a motor support portion 32 provided on the upper part of the caster 2. The screw shaft portion 31b is a screw shaft that rotates in response to the rotation of the drive motor 31a, and serves as the rotational drive source for the ball screw mechanism 31. The nut portion 31c is a nut that is screwed onto the screw shaft portion 31b. In this embodiment, the rotation of the screw shaft portion 31b relative to the nut portion 31c causes the screw shaft portion 31b to be displaced vertically, thereby raising or lowering the motor support portion 32 and adjusting the support height h of the caster 2.

[0044] The motor support section 32 is a highly rigid support member (housing) that stabilizes the mounting position of the drive motor 31a. Furthermore, the motor support section 32 is provided with multiple through holes through which fastening members for connecting and fixing to the base section 11 are inserted.

[0045] The nut support portion 33 is a highly rigid support member (housing) that connects the nut portion 31c and the caster bracket 22.

[0046] The bearing portion 34 is interposed between the screw shaft portion 31b and the motor support portion 32, and between the caster bracket 22 and the nut support portion 33, and is a bearing for supporting the relative rotation of these components. Each bearing section 34 is constructed using, for example, tapered roller bearings or ball bearings.

[0047] The spacer 35 is interposed between the drive motor 31a and the motor support portion 32, and between the nut portion 31c and the nut support portion 33, and is a spacing member that separates each component by a predetermined distance. The fastening bolt 36 is a fastening member for securely fastening and fixing these components.

[0048] As described above, the support height h is adjusted by configuring the caster 2 and the height adjustment mechanism 3.

[0049] More specifically, as shown in Figure 4, the height adjustment mechanism 3 has a nut portion 31c fixed to the caster 2 side via a nut support portion 33 and a spacer 35, and the screw shaft portion 31b is rotated by the drive motor 31a, causing the screw shaft portion 31b to be displaced axially relative to the nut portion 31c.

[0050] In other words, the screw shaft portion 31b is supported by the bearing portion 34 for rotation and axial load, and the screw shaft portion 31b itself is displaced vertically in accordance with the rotation of the drive motor 31a. As the screw shaft portion 31b moves up and down, the motor support portion 32 connected to the screw shaft portion 31b rises or falls, and the support height h of the caster 2 is adjusted. In Figure 4, the flow from (a) to (b) shows an example in which the support height h decreases to h' due to the downward displacement of the screw shaft portion 31b.

[0051] Thus, the height adjustment mechanism 3 can continuously and accurately adjust the vertical position of the casters 2 by the rotation of the ball screw mechanism 31. By appropriately changing the support height h for each caster 2, the orientation of the mounting surface F of the vehicle body 1 can be corrected to a desired horizontal orientation.

[0052] <Mold exchange system> The mold exchange system S will be explained below using Figures 5 to 7.

[0053] <<Structure>> As shown in Figures 5 to 7, the mold exchange system S of this embodiment comprises a device X, a connected object J that receives the mold M from the device X, and an external management device L.

[0054] The device X is configured to move a joint p provided on the mounting surface F to a position where it can be connected to the part to be joined q when transferring a mold M to the object to be connected J.

[0055] Here, the joint portion p is shown as a simple protrusion, but it is a region for positioning relative to the connection target J when the mold M is transferred, and includes positioning mechanisms such as positioning pins, positioning holes, guide portions, contact portions, electromagnetic adsorption portions, and camera markers. Furthermore, although the joined portion q is shown as a simple hole, it is a region that works in cooperation with the joined portion p to define the transfer position of the mold M, and includes, for example, positioning receiving mechanisms such as positioning pins, positioning holes, guide grooves, contact blocks, electromagnetic adsorption metal plates, and camera recognition markers.

[0056] The connection target J (including the part to be joined q) is an injection molding machine, a press molding machine, etc., and is configured as a receiving device for loading or unloading the mold M. The joint p and the jointed part q are positionally aligned, allowing the mold M to be transferred smoothly.

[0057] The external control device L is a management device that manages the location information of multiple connected objects J installed in the factory, the type of mold M, instructions for mold replacement, etc., and transmits the location information of connected objects J, information regarding the relative position of the joint p and the joined part q, or information regarding the adjustment amount of the height adjustment mechanism 3, etc., to the control device 200 of device X. The communication can be either wired or wireless.

[0058] <<Operation overview>> First, as shown in Figure 5(a), the device X travels based on the location information of the connection target J obtained from the external management device L, and moves the joint p to a predetermined proximity position where it can be connected to the connection target q.

[0059] Figure 5(b) shows map information of the target area generated by the external management device L, and includes areas for movement within the factory, restricted areas (shaded areas), destination areas (shaded areas), work areas (black rectangular areas), etc. The map information is generated by analyzing the factory layout, the positional relationships of static obstacles, and the passage structure based on image information and sensor information acquired by an environmental recognition device connected to an external management device L.

[0060] Based on this map information, the external management device L determines the routes that device X can travel and, while sequentially updating the relative relationship between device X's current position and its destination (connection target J), provides device X with route information and stopping position information. Furthermore, if dynamic obstacles such as other moving objects (e.g., autonomous mobile robots) moving within the factory are detected in addition to the location of static obstacles, safe path guidance will be provided that takes their presence into account.

[0061] Device X autonomously travels based on map and route information provided by the external management device L, and enters the work area set around the connected target J. At this time, device X accurately determines its own position relative to the connection target J by aligning additional environmental information acquired during driving with its position in the map information.

[0062] As described above, in the approach operation shown in Figure 5, the destination area is determined using map information held by the external management device L, and the device X is guided to the connection target J while avoiding interference with static obstacles and dynamic obstacles detected as needed. This ensures that the necessary preparations for aligning the joint p and the jointed part q are carried out in order to begin the mold change operation.

[0063] Next, as shown in Figure 6, when the device X reaches the position immediately in front of the connection target J based on the map information and route information held by the external management device L, the control device 200 accurately measures the relative positional relationship between the joint p and the connected part q based on the marker provided on the top surface 12, the reference marker provided on the connection target J side, or position recognition information acquired from the surrounding environment sensor.

[0064] At this time, the device X performs a fine adjustment operation to align the joint p with the part to be joined q. Specifically, the sliding part 14 corrects the left-right direction, and the steering mechanism W corrects the front-rear and turning directions. As a result, positional errors in the connection axis direction (x-axis direction) and width direction (y-axis direction) between the two are successively eliminated.

[0065] Furthermore, considering the possibility of workers or other moving objects being present around the connection target J, the device X monitors surrounding static and dynamic obstacles and controls its movement speed to avoid exceeding the approach limit distance. It aligns the joint p while avoiding the risk of contact, stopping or slowing down as necessary.

[0066] Furthermore, at this time, the control device 200 corrects the posture of the vehicle body 1 using the leveling means 300 so that no step difference occurs in the height direction (z-axis direction) between the mounting surface F and the mold table on the connection target J side. Here, static leveling or dynamic leveling, as described later, is selectively performed depending on the situation, so that the vertical position of the mounting surface F is aligned with the transfer height of the joined part q.

[0067] As described above, the operation at close range shown in Figure 6 is performed through the coordinated action of position-based orientation control, safety control to avoid contact risk, and attitude correction in the height direction. This ensures that the positions of the joint p and the jointed part q are precisely aligned during the subsequent mold transfer process.

[0068] Next, as shown in Figure 7, with the joint p and the jointed part q precisely aligned, the device X drives the lifting device 4 to load or unload the mold M. At this time, the mounting surface F is held approximately horizontal by the static leveling or dynamic leveling described above, thus preventing steps or tilts from occurring when the mold M is transferred.

[0069] After the mold M has been securely received onto the mounting surface F on the device X side, the control device 200 determines that the receipt of the mold M is complete. Since any load changes or posture fluctuations that may occur during receipt are appropriately corrected by static leveling or dynamic leveling, it can be confirmed that the mounting state of the mold M is stable.

[0070] After determining that the receipt is complete, device X begins traveling towards the next destination or storage location, following instructions from the external management device L. Based on map information and location information, device X autonomously determines its route and moves accordingly.

[0071] As described above, the mold exchange system S of this embodiment can stably perform the loading and unloading of molds M by combining high-precision alignment of the joint portion p and the jointed portion q, and posture correction by leveling.

[0072] <Leveling Method> The leveling method according to this embodiment will be described below with reference to Figures 8 to 10. The leveling method described below is performed by the leveling means 300.

[0073] Figure 8 shows the overall processing flow of the leveling method according to this embodiment. This leveling method includes the steps of "generating a control signal based on the inclination of the vehicle body 1" and "driving the height adjustment mechanism 3 based on the control signal to adjust the lifting direction of the lifting device 4 to a nearly vertical direction by making the mounting surface F nearly horizontal," which will be described in detail below.

[0074] First, in the leveling start condition determination step S101, it is determined whether the conditions for performing leveling have been met, such as whether the vehicle body 1 is stopped or whether the mold M is being loaded or unloaded. Note that this step is for confirming the prerequisites for starting leveling and does not correspond to any of the steps mentioned above.

[0075] Next, in the correction amount determination step S102, a correction amount is calculated to offset the attitude error of the vehicle body 1 based on the tilt of the vehicle body 1 in the roll direction and pitch direction detected by the tilt sensor 210, the change in load distribution detected by the load cell 220, or pre-stored position information and adjustment amount data. Step S102 corresponds to the "step of generating a control signal based on the tilt of the vehicle body 1" described above. Furthermore, it is preferable that the tilt of the vehicle body 1 in the roll direction and the pitch direction is 1 degree or less, each.

[0076] Next, in the height adjustment mechanism drive step S103, the height adjustment mechanism 3 of each caster 2 is driven individually based on the correction amount determined in the correction amount determination step S102. As a result, the mounting surface F is adjusted to be approximately horizontal, and the lifting direction of the lifting device 4 becomes approximately vertical. Step S103 corresponds to the step described above, "driving the height adjustment mechanism 3 based on the control signal and adjusting the lifting direction of the lifting device 4 to a nearly vertical direction by making the mounting surface F nearly horizontal."

[0077] Next, in the leveling completion determination step S104, it is determined whether the posture of the vehicle body 1 has converged to a predetermined allowable range based on the correction amount determination step S102 and the height adjustment mechanism drive step S103. If convergence has not occurred, the process returns to the correction amount determination step S102 and the correction process is repeated. If convergence occurs, the entire leveling process is completed.

[0078] Based on the above, the device X can automatically correct the tilt of the vehicle body 1 caused by unevenness of the floor surface or fluctuations in the load of the mold M, and can stably perform the lifting and lowering operation when loading or unloading the mold M.

[0079] <<Static Leveling>> In this embodiment, "static leveling" refers to a process that, while the vehicle body 1 of the device X is stationary, corrects the tilt of the vehicle body 1 caused by unevenness or slope of the floor surface and adjusts the mounting surface F to be approximately horizontal. Static leveling is performed before the start of loading or unloading of the mold M, and its purpose is to maintain the lifting direction of the lifting device 4 in a substantially vertical direction.

[0080] In this embodiment, there are two methods for static leveling: (1) A teaching method (see Figure 9(a)) in which the correction amount is determined based on the stopping position information of the vehicle body 1 (hereinafter referred to as static position information) and static adjustment amount data corresponding to that position. (2) A sensor system in which the tilt of the vehicle body 1 in the roll direction and pitch direction is directly detected by the tilt sensor 210 and the amount of correction is determined (see Figure 9(b)). In addition, in the static leveling methods shown in Figure 9, all processes except for the height adjustment mechanism drive step (S205, S305) and the leveling completion determination step (S206, S306) are detailed processes of the correction amount determination step S102 shown in Figure 8. Furthermore, the correction amount determination step within each flow (S204, S304) functions as the final calculation step for the detailed processing.

[0081] <<<Static Leveling-Teaching Method>>> Figure 9(a) shows the processing flow for static leveling, which adjusts the height using static position information and adjustment amount data.

[0082] In the stop position acquisition step S201, it is detected that the device X has reached a predetermined stop position relative to the connected object J.

[0083] In the static adjustment amount data reading step S202, the static adjustment amount data stored in memory 202 is read. The static adjustment amount data is the recommended height adjustment amount for each position obtained from past teaching.

[0084] In the target height calculation step S203, the "target height" at which the mounting surface F should be horizontal is calculated based on the current stopping position and static adjustment amount data.

[0085] In the correction amount determination step S204, the correction amount is calculated as the difference between the current height and the target height.

[0086] In the height adjustment mechanism drive step S205, the height adjustment mechanism 3 for each caster 2 is driven based on the correction amount calculated in the correction amount determination step S204.

[0087] In the leveling completion determination step S206, it is determined whether the height of the corrected mounting surface F has converged to the target height. If convergence has not occurred, the process returns to the correction amount determination step S204, and the height correction based on the static adjustment amount data is repeated. If convergence occurs, the static leveling process based on the teaching method is terminated.

[0088] As described above, with the teaching-type static leveling, stable height correction can be performed based on the stopping position without using the tilt sensor 210, and the mounting surface F can be maintained in a nearly horizontal position.

[0089] <<<Static Leveling Sensor System>>> Figure 9(b) shows the processing flow of static leveling using the tilt sensor 210.

[0090] In the tilt sensor value acquisition step S301, the tilt amount of the vehicle body 1 in the roll direction and pitch direction is acquired by the tilt sensor 210.

[0091] In the tilt calculation step S302, the attitude error (tilt amount) is calculated based on the acquired tilt value, indicating how much the current vehicle posture deviates from the desired horizontal posture.

[0092] In the tilt tolerance determination step S303, it is determined whether the calculated tilt amount is within a predetermined tolerance range. If it is within the tolerance range, the vehicle body posture is approximately horizontal, and the static leveling process is terminated.

[0093] In the correction amount determination step S304, the correction amount for how much each caster 2 should be moved up or down is determined based on the direction and magnitude of the inclination.

[0094] In the height adjustment mechanism drive step S305, the height adjustment mechanism 3 is driven based on the correction amount calculated in the correction amount determination step S304.

[0095] In the leveling completion determination step S306, the posture of the corrected vehicle body 1 is measured again, and it is determined whether or not the amount of inclination has converged to a predetermined allowable range. If convergence has not occurred, the process returns to the tilt calculation step S302 and repeats the recalculation and correction of the attitude error. When the attitude converges within the acceptable range, the static leveling process using the sensor method is completed.

[0096] As described above, the sensor-based static leveling system can sequentially correct the tilt of the vehicle body 1 caused by unevenness in the floor surface, maintain the mounting surface F in a nearly horizontal position, and adjust the lifting direction of the lifting device 4 to be nearly vertical.

[0097] <<Dynamic Leveling>> In this embodiment, "dynamic leveling" refers to a process that corrects the tilt of the vehicle body 1 caused by changes in the load state acting on the vehicle body 1 in situations where the load on the mounting surface F fluctuates in real time, such as when loading or unloading a mold M, and maintains the mounting surface F in a substantially horizontal position. The purpose of dynamic leveling is to suppress disturbances in the vehicle's posture due to fluctuations in load distribution and to maintain the lifting direction of the lifting device 4 in a substantially vertical direction. In this embodiment, the tilt of the vehicle body 1 caused by the changes in the load conditions described above is explained as being due to the elastic deformation of each caster 2, but it also includes tilting due to sinking of the vehicle body structure or support parts, or a combination of these factors.

[0098] There are two methods for dynamic leveling in this embodiment. (1) A teaching method (see Figure 10(a)) in which the correction amount is determined based on the position information of the mold M (hereinafter referred to as dynamic position information) and the dynamic adjustment amount data corresponding to that position. (2) A sensor-based method (see Figure 10(b)) in which the amount of elastic deformation of the caster 2 is calculated from the change in load distribution detected by the load cell 220, and the correction amount is determined. In addition, in the dynamic leveling methods shown in Figure 10, all processes except for the height adjustment mechanism drive step (S404, S506) and the leveling completion determination step (S405, S507) are detailed processes of the correction amount determination step S102 shown in Figure 8. Furthermore, the correction amount determination steps within each flow (S403, S505) function as the final calculation steps for the detailed processing.

[0099] <<<Dynamic Leveling-Teaching Method>>> Figure 10(a) shows the processing flow for dynamic leveling, which determines the correction amount based on dynamic position information and dynamic adjustment amount data.

[0100] In the mold position acquisition step S401, dynamic position information is acquired that indicates the position of the mold M on the mounting surface F. The dynamic position information is determined based on the front-to-back position, left-to-right position, or marker reading of the mold M.

[0101] In the dynamic adjustment amount data reading step S402, the dynamic adjustment amount data that has been pre-stored in memory 202 is read. The dynamic adjustment amount data is determined by teaching the correction amount necessary to counteract the body tilt caused by the elastic deformation of the caster 2 when the mold M is in a specific position.

[0102] In the correction amount determination step S403, the height adjustment amount (correction amount) for each caster 2 is determined based on the current mold position and dynamic adjustment amount data.

[0103] In the height adjustment mechanism drive step S404, the height adjustment mechanism 3 is driven individually based on the correction amount calculated in the correction amount determination step S403.

[0104] In the leveling completion determination step S405, it is determined whether or not the loading or unloading of the mold M is continuing. If transport is continuing, the process returns to mold position acquisition step S401 and repeats the correction process based on dynamic position information. When transport is completed, the dynamic leveling process using the teaching method is terminated.

[0105] As described above, with the teaching-type dynamic leveling, even during mold transport where load fluctuations are large, the correction amount according to the mold position is appropriately applied, and the mounting surface F can be maintained in a nearly horizontal position.

[0106] <<<Dynamic Leveling Sensor System>>> Figure 10(b) shows the dynamic leveling process flow, which determines the correction amount based on the change in load distribution detected by the load cell 220.

[0107] In the loading / unloading status determination step S501, it is determined whether the mold is being loaded, unloaded, or in any other state where dynamic leveling should be performed.

[0108] In the load value acquisition step S502, the load value acting on each caster 2 is acquired by the load cell 220 provided on each caster 2.

[0109] In the load distribution change calculation step S503, the difference between the current load value and the previous load value is calculated, and the change in load distribution caused by the change in the position of the mold M is determined.

[0110] In the elastic deformation calculation step S504, the amount of elastic deformation of each caster 2 is estimated based on the change in load distribution. The elastic deformation model can be a known model corresponding to the support stiffness of the caster 2, such as a linear spring model.

[0111] In the correction amount determination step S505, the height adjustment amount (correction amount) necessary to offset the calculated elastic deformation amount is determined.

[0112] In the height adjustment mechanism drive step S506, the height adjustment mechanism 3 is driven based on the correction amount obtained in the correction amount determination step S505.

[0113] In the leveling completion determination step S507, it is determined whether or not mold transport is continuing. If transport is continuing, the process returns to the load value acquisition step S502, and the calculation and correction of elastic deformation based on the change in load distribution is repeated. When transport is finished, the sensor-based dynamic leveling process ends.

[0114] Based on the above, the sensor-based dynamic leveling system reflects changes in load distribution during mold transport in real time, maintaining the vehicle's posture nearly horizontal, thereby enabling stable mold transport operations.

[0115] <Effects> According to this disclosure, disturbances in the vehicle body posture of the device X caused by unevenness of the floor surface or fluctuations in the load of the mold M can be automatically and accurately corrected by the height adjustment mechanism 3. As a result, the horizontality of the mounting surface F is stably maintained throughout the entire mold transport process, and the loading and unloading of the mold M by the lifting device 4 can always be performed in a substantially vertical direction. As a result, jamming and collisions caused by steps and inclinations between the mold M and the transfer section on the molding machine are prevented, and the reliability and reproducibility of mold change operations are greatly improved. Furthermore, by combining static and dynamic leveling using positional and load information, stable replacement quality can be ensured that is independent of environmental fluctuations and changes in mold position.

[0116] <Example of changes> The shapes and dimensions of the components shown in the above embodiment are merely examples and can be modified in various ways based on design requirements, etc.

[0117] For example, in this embodiment, the vehicle body 1 is supported by three casters 2, but the number of casters 2 can be any integer of 3 or more, and it may be supported by four or more casters 2. Furthermore, the casters 2 whose support height h can be adjusted by the height adjustment mechanism 3 do not need to be all of the multiple casters 2 that support the vehicle body 1, as in this embodiment; at least one is sufficient, or there may be two or more. Geometrically, a plane is determined by three points, so for example, in the case of three-point support, if the support height h of at least two casters 2 can be adjusted, the inclination of the mounting surface F can be freely controlled.

[0118] Furthermore, the height adjustment mechanism 3 is not limited to the ball screw mechanism 31, but can be any mechanism that allows for individual adjustment of the support height h, such as a trapezoidal screw mechanism, a linear actuator, or a hydraulic or pneumatic telescopic mechanism.

[0119] Furthermore, although the vehicle body 1 is configured as an autonomously driven unmanned transport vehicle, it can also be applied to a configuration in which the vehicle is towed by an external unmanned transport vehicle (tow vehicle), or to a vehicle body that is driven by manual operation by an operator.

[0120] Furthermore, the lifting device 4 that raises and lowers the mounting surface F is not limited to a configuration using an electric screw mechanism; any device capable of raising and lowering the mold M to the desired height is acceptable, such as a link mechanism, hydraulic cylinder, or scissor lift mechanism.

[0121] Furthermore, the leveling means 300 is not limited to a configuration using a tilt sensor 210 or a load cell 220, but can also be configured to use a laser rangefinder, an optical position sensor, etc. in combination, or to control the system based solely on height correction information acquired from an external management device L.

[0122] Furthermore, device X is not limited to the use of loading or unloading molds to and from molding machines, but can also be applied to the transfer of heavy objects between press molds, die-casting molds, automated mold warehouses, mold temperature control devices, mold maintenance devices, etc., and the leveling function can be used to absorb steps and improve connection accuracy between these pieces of equipment.

[0123] In addition, the shape, material, dimensions, arrangement, control method, sensing method, data storage method, and correction amount calculation algorithm of each component can be appropriately modified within the scope described in the claims.

[0124] In the application documents, the term "abbreviated" is a concept that means the shape that follows has been chamfered or rounded, and that the elements constituting the shape have been modified or altered in length to the extent that it does not impede the purpose of the shape.

[0125] The disclosures herein include the following mobile mold changers, mold changers, leveling methods, and programs.

[0126] Item [1] A mobile mold changing device that loads or unloads molds between and to a connected object, The invention comprises a movable vehicle body having a mounting surface for placing a mold, a plurality of casters supporting the vehicle body, an electrically operated height adjustment mechanism capable of individually adjusting the support height of at least one of the plurality of casters, a lifting device for raising and lowering the aforementioned mounting surface, and a leveling means that drives the height adjustment mechanism to generate a signal for correcting the tilt of the vehicle body, The leveling means drives the height adjustment mechanism to make the aforementioned mounting surface substantially horizontal, thereby generating a control signal that allows the lifting direction of the lifting device to be adjusted substantially vertically. Mobile mold changing device. Item [2] The leveling means generates the control signal for driving the height adjustment mechanism so as to compensate for the tilt of the vehicle body caused by the unevenness of the floor surface on which the vehicle body moves. The mobile mold changing device described in [1]. Item [3] The leveling means generates the control signal for driving the height adjustment mechanism based on the position information of the vehicle body stored in advance and the adjustment amount data of the height adjustment mechanism corresponding to the position information. [2] The mobile mold changing device described above. Item [4] The vehicle is further equipped with a tilt sensor that detects the tilt of the vehicle body, The leveling means generates the control signal for driving the height adjustment mechanism based on the tilt of the vehicle body detected by the tilt sensor. [3] The mobile mold changing device described above. Item [5] The leveling means generates the control signal for driving the height adjustment mechanism in order to suppress the tilting of the vehicle body caused by changes in the load state acting on the vehicle body during loading or unloading of the mold onto the aforementioned mounting surface. The mobile mold changing device described in [1]. Item [6] The leveling means generates the control signal for driving the height adjustment mechanism during the loading or unloading of the mold, based on the position information of the mold on the aforementioned mounting surface, which is stored in advance and changes during the loading or unloading of the mold, and the adjustment amount data of the height adjustment mechanism corresponding to the position information. [5] The mobile mold changing device described below. Item [7] The aforementioned plurality of casters are further equipped with load cells that detect the load applied to each of them, The leveling means generates the control signal for driving the height adjustment mechanism based on the change in load detected by each load cell. [5] The mobile mold changing device described below. Item [8] The leveling means further comprises a calculation means for calculating the amount of elastic deformation of each caster based on the change in load distribution obtained from each load cell, and a determination means for determining the amount of correction of the height adjustment mechanism necessary to offset the calculated amount of elastic deformation. The mobile mold changing device described in [7]. Item [9] The vehicle body is either an autonomously capable unmanned transport vehicle, or is towed by an autonomously capable unmanned transport vehicle. A mobile mold changing device as described in any of [1] to [8]. Item

[10] The aforementioned vehicle is driven by the operator's control. A mobile mold changing device as described in any of [1] to [9]. Item

[11] A mobile mold changing device as described in any of [1] to

[10] , The mobile mold changing device includes an external management device that transmits to the control device the position information of the connected object for mold transfer, or the adjustment amount information of the height adjustment mechanism, at least one of the above. A mold change system. Item

[12] A method for leveling the aforementioned mounting surface in a mobile mold changing device that performs loading or unloading of molds between a connected object, comprising: a movable vehicle having a mounting surface for mounting a mold; a plurality of casters supporting the vehicle; an electrically operated height adjustment mechanism capable of individually adjusting the support height of at least one of the plurality of casters; and a lifting device for raising and lowering the aforementioned mounting surface, the device. The steps include generating a control signal based on the tilt of the vehicle body, Based on the aforementioned control signal, the height adjustment mechanism is driven to make the aforementioned mounting surface substantially horizontal, thereby adjusting the lifting direction of the lifting device to substantially vertical. Having, Leveling method. Item

[13] A program that causes a computer to execute the leveling method described in

[12] . [Explanation of Symbols]

[0127] X: Mobile mold changing device 1: Vehicle body F: Mounting surface 2: Caster 3: Height adjustment mechanism 4: Lifting device 200: Control device 300: Leveling method S: Mold changing system J: Connection target L: External management device M: Mold p: Joint q: The joint

Claims

1. A mobile mold changing device that loads or unloads molds between and to a connected object, The invention comprises a movable vehicle body having a mounting surface for placing a mold, a plurality of casters supporting the vehicle body, an electrically operated height adjustment mechanism capable of individually adjusting the support height of at least one of the plurality of casters, a lifting device for raising and lowering the aforementioned mounting surface, and a leveling means that drives the height adjustment mechanism to generate a signal for correcting the tilt of the vehicle body. The leveling means drives the height adjustment mechanism based on pre-stored position information of the vehicle body and adjustment amount data of the height adjustment mechanism corresponding to the position information, in order to counteract the tilt of the vehicle body caused by unevenness in the floor surface on which the vehicle body moves, thereby making the aforementioned mounting surface substantially horizontal and generating a control signal that allows the lifting direction of the lifting device to be adjusted substantially vertically. Mobile mold changing device.

2. A mobile mold changing device for loading or unloading molds between and a connected object, The invention comprises a movable vehicle body having a mounting surface for placing a mold, a plurality of casters supporting the vehicle body, an electrically operated height adjustment mechanism capable of individually adjusting the support height of at least one of the plurality of casters, a lifting device for raising and lowering the aforementioned mounting surface, and a leveling means that drives the height adjustment mechanism to generate a signal for correcting the tilt of the vehicle body. The leveling means generates a control signal that allows the lifting direction of the lifting device to be adjusted to a substantially vertical direction, by driving the height adjustment mechanism based on pre-stored and fluctuating position information of the mold on the aforementioned mounting surface and adjustment amount data of the height adjustment mechanism corresponding to the position information, thereby making the aforementioned mounting surface substantially horizontal, in order to suppress the tilting of the vehicle body caused by changes in the load state acting on the vehicle body during loading or unloading of the mold onto or from the aforementioned mounting surface. Mobile mold changing device.

3. A mobile mold changing device for loading or unloading molds between and a connected object, The invention comprises a movable vehicle body having a mounting surface for placing a mold, a plurality of casters supporting the vehicle body, an electrically operated height adjustment mechanism capable of individually adjusting the support height of at least one of the plurality of casters, a lifting device for raising and lowering the aforementioned mounting surface, a leveling means that drives the height adjustment mechanism to generate a signal for correcting the tilt of the vehicle body, and load cells provided on the plurality of casters for detecting the load applied to each of them, The leveling means drives the height adjustment mechanism based on the load changes detected by each load cell, in order to suppress the tilting of the vehicle body caused by changes in the load state acting on the vehicle body during loading or unloading of the mold onto the aforementioned mounting surface, thereby making the aforementioned mounting surface substantially horizontal and generating a control signal that allows the lifting direction of the lifting device to be adjusted substantially vertically. Mobile mold changing device.

4. The leveling means further comprises a calculation means for calculating the amount of elastic deformation of each caster based on the change in load distribution obtained from each load cell, and a determination means for determining the amount of correction of the height adjustment mechanism necessary to offset the calculated amount of elastic deformation. The mobile mold changing device according to claim 3.

5. The vehicle body is either an autonomously capable unmanned transport vehicle, or is towed by an autonomously capable unmanned transport vehicle. A mobile mold changing device according to any one of claims 1 to 4.

6. The aforementioned vehicle is driven by the operator's control. A mobile mold changing device according to any one of claims 1 to 4.

7. A mobile mold changing device according to any one of Claims 1 to 4, The mobile mold changing device includes an external management device that transmits to the control device the position information of the connected object for mold transfer, or the adjustment amount information of the height adjustment mechanism, at least one of the above. A mold change system.

8. A method for leveling the aforementioned mounting surface in a mobile mold changing device that performs loading or unloading of molds between a connected object, comprising: a movable vehicle having a mounting surface for mounting a mold; a plurality of casters supporting the vehicle; an electrically operated height adjustment mechanism capable of individually adjusting the support height of at least one of the plurality of casters; and a lifting device for raising and lowering the aforementioned mounting surface, the device. The steps include generating a control signal based on pre-stored position information of the vehicle body and adjustment amount data of the height adjustment mechanism corresponding to the position information, in order to compensate for the tilt of the vehicle body caused by unevenness in the floor surface on which the vehicle body moves, Based on the aforementioned control signal, the height adjustment mechanism is driven to make the aforementioned mounting surface substantially horizontal, thereby adjusting the lifting direction of the lifting device to substantially vertical. Having, Leveling method.

9. A method for leveling the aforementioned mounting surface in a mobile mold changing device that performs loading or unloading of molds to and from a connected object, comprising: a movable vehicle having a mounting surface for mounting a mold; a plurality of casters supporting the vehicle; an electrically operated height adjustment mechanism capable of individually adjusting the support height of at least one of the plurality of casters; and a lifting device for raising and lowering the aforementioned mounting surface, the device being used to load or unload molds to and from a connected object. In order to suppress the tilting of the vehicle body caused by changes in the load state acting on the vehicle body during loading or unloading of the mold onto the mounting surface, the steps include generating a control signal based on the position information of the mold on the aforementioned mounting surface, which is stored in advance and changes during loading or unloading of the mold, and the adjustment amount data of the height adjustment mechanism corresponding to the position information, Based on the aforementioned control signal, the height adjustment mechanism is driven to make the aforementioned mounting surface substantially horizontal, thereby adjusting the lifting direction of the lifting device to substantially vertical. Having, Leveling method.

10. A method for leveling the aforementioned mounting surface in a mobile mold changing device that loads or unloads molds to and from a connected object, comprising: a movable vehicle having a mounting surface for mounting a mold; a plurality of casters supporting the vehicle; an electrically operated height adjustment mechanism capable of individually adjusting the support height of at least one of the plurality of casters; a lifting device for raising and lowering the aforementioned mounting surface; and load cells provided on the plurality of casters for detecting the load applied to each of them, the device being used to load or unload molds. The steps include generating a control signal based on the load change detected by each load cell in order to suppress the tilting of the vehicle body caused by a change in the load state acting on the vehicle body during loading or unloading of the mold onto the mounting surface, Based on the aforementioned control signal, the height adjustment mechanism is driven to make the aforementioned mounting surface substantially horizontal, thereby adjusting the lifting direction of the lifting device to substantially vertical. Having, Leveling method.

11. A program that causes a computer to execute the leveling method described in any one of Claims 8 to 10.

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