State monitoring system in hammer forging device, state monitoring device, and state monitoring method

Abstract

To provide a state monitoring system in a hammer forging device which can accurately monitor a state of a hammer forging device under a harsh environment, and to provide a state monitoring device and a state monitoring method.SOLUTION: A ram 4 has a side surface. A lifting mechanism 11 moves up or down the ram 4. Ram position sensors 1, 2 detect clearances L1, L2 between the sensors and the side surface of the ram 4 which change as the ram 4 is moved up or down by the lifting mechanism 11. A sensor controller 30 monitors a state of a hammer forging device 100 based on the clearances L1, L2 between the ram position sensors 1, 2 and the side surface of the ram 4.SELECTED DRAWING: Figure 6

Description

[Technical field]

[0001] The present disclosure relates to a condition monitoring system, a condition monitoring device, and a condition monitoring method for a hammer forging machine. [Background technology]

[0002] A conventional hammer forging device is described in, for example, JP 2019-115924 A (Patent Document 1). The processing device in this publication has a detection device that detects a signal including position information of a processing tool that processes a workpiece. An imaging device, a laser displacement meter, and a linear scale are used as the detection device. The video camera and the processing device are installed in different positions, so that the ram position detection signal is acquired while suppressing the influence of vibrations of the processing device. [Prior art documents] [Patent documents]

[0003] [Patent Document 1] JP 2019-115924 A Summary of the Invention [Problem to be solved by the invention]

[0004] Hammer forging is a process that operates in a harsh environment (vibration, impact, temperature, mold release agents), and there is a demand for accurate monitoring of the state of the hammer forging equipment in such an environment.

[0005] An object of the present disclosure is to provide a condition monitoring system, a condition monitoring device, and a condition monitoring method for a hammer forging device that can accurately monitor the condition of the hammer forging device even in harsh environments. [Means for solving the problem]

[0006] The disclosed condition monitoring system for a hammer forging device includes a ram, a lifting mechanism, a ram position sensor, and a controller. The ram has a side. The lifting mechanism raises and lowers the ram. The ram position sensor detects a distance to the side of the ram that changes as the lifting mechanism raises and lowers the ram. The controller monitors the condition of the hammer forging device based on the distance between the ram position sensor and the side of the ram.

[0007] The condition monitoring device for a hammer forging device disclosed herein is a condition monitoring device for a hammer forging device having a ram with a side surface and a lifting mechanism for raising and lowering the ram, and includes a ram position sensor and a controller. The ram position sensor detects the distance to the side surface of the ram that changes as the ram is raised and lowered by the lifting mechanism. The controller monitors the condition of the hammer forging device based on the distance between the ram position sensor and the side surface of the ram.

[0008] The disclosed method for monitoring the condition of a hammer forging device is a method for monitoring the condition of a hammer forging device having a ram that has a side surface and moves up and down, and includes the following steps.

[0009] The distance to the side of the ram, which changes as the ram rises and falls, is detected, and the state of the hammer forging device is monitored based on the detected distance. Effect of the Invention

[0010] According to the present disclosure, it is possible to realize a condition monitoring system, a condition monitoring device, and a condition monitoring method for a hammer forging device that can accurately monitor the condition of the hammer forging device even in harsh environments. [Brief description of the drawings]

[0011] [Figure 1] 1 is a front view showing a configuration of a hammer forging device according to an embodiment of the present disclosure. FIG. [Diagram 2] FIG. 2 is a cross-sectional view taken along line II-II in FIG. [Diagram 3] FIG. 2 is a cross-sectional view taken along line III-III in FIG. [Figure 4] 2 is a front view showing a state in which the ram is raised in the hammer forging device of FIG. 1. [Diagram 5] FIG. 1 shows the lower limit position (A) and upper limit position (B) of the ram to explain the distance between the ram and the ram height sensor, and FIG. 2 shows the lower limit position (C) and upper limit position (D) of the ram to explain the distance between the ram and the ram gap sensor. [Figure 6] 1 is a diagram showing a configuration of a state monitoring system for a hammer forging device in an embodiment of the present disclosure. FIG. [Figure 7] FIG. 7 is a diagram showing functional blocks of a sensor controller shown in FIG. 6. [Figure 8] 13 is a diagram comparing the time change of the ram height during normal impact with the normal impact threshold value and the actual impact waveform. FIG. [Figure 9] 13 is a diagram comparing the time change of the ram height during an abnormal impact with a normal impact threshold value and an actual impact waveform. FIG. [Figure 10] FIG. 13 is a diagram for explaining a backlash abnormality, showing the relationship between the height of the ram and the backlash of the ram. [Figure 11] FIG. 1 is a first flow chart showing a method for monitoring a condition of a hammer forging device according to an embodiment of the present disclosure. [Figure 12] FIG. 2 is a second flow chart showing the method for monitoring the condition of a hammer forging device according to an embodiment of the present disclosure. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0012] Hereinafter, embodiments of the present disclosure will be described with reference to the drawings.

[0013] In the specification and drawings, the same or corresponding components are denoted by the same reference numerals, and redundant explanations are not repeated. In addition, in the drawings, configurations may be omitted or simplified for convenience of explanation. In addition, at least some of the embodiments and modifications may be combined with each other in any desired manner.

[0014] In the following description, the up-down direction is the direction in which the ram 4 rises and falls. The left-right direction is the direction perpendicular to the up-down direction and in which the frame 6 is located relative to the ram 4. The front-rear direction is the direction perpendicular to a plane that includes the up-down direction and the left-right direction that are perpendicular to each other, and in which the frame 6 is not located relative to the ram 4.

[0015] <Configuration of hammer forging device>

[0016] Fig. 1 is a front view showing a configuration of a hammer forging device according to an embodiment of the present disclosure, Fig. 2 and Fig. 3 are cross-sectional views taken along lines II-II and III-III in Fig. 1, respectively.

[0017] 1, the hammer forging device 100 of this embodiment is, for example, a hydraulic hammer forging device, but may also be an air hammer forging device. The hammer forging device 100 of this embodiment may also be a hydraulic hammer forging device that utilizes a hydraulic pressure (for example, water pressure) other than hydraulic pressure.

[0018] The hammer forging device 100 of this embodiment has a ram 4, a rod 5, a frame 6, a guide 7, an upper die 8, a lower die 9, a lower die fixing base 10, and a lifting mechanism 11. The frame 6 is a housing of the hammer forging device 100 and has a processing space 6a. The frame 6 may have a divided frame structure in which a frame main body 6b1 and an anvil 6b2 are divided and fastened together, or may have an integrated frame structure in which the frame main body 6b1 and the anvil 6b2 are integrated together.

[0019] A ram 4 is disposed within the machining space 6a. The ram 4 is, for example, a metal block. A rod 5 is connected to the upper end of the ram 4. The ram 4 and the rod 5 are supported by a frame 6 so as to be movable up and down. This allows the ram 4 to be movable up and down within the machining space 6a.

[0020] A pair of left and right guides 7 are attached to the frame 6. The pair of guides 7 are arranged with a gap between them. The pair of guides 7 hold the ram 4 in place from the left and right. Each of the pair of guides 7 faces the ram 4 with a gap between them. The pair of guides 7 guide the ram 4 as it rises and falls.

[0021] An upper die 8 is attached to the lower end of the ram 4. The upper die 8 rises and falls within the processing space 6a together with the ram 4. A lower die 9 is disposed below the upper die 8 so as to face the upper die 8. The lower die 9 is attached to the frame 6 having an integral frame structure or the anvil 6b having a split frame structure via a lower die fixing base 10.

[0022] The lifting mechanism 11 raises and lowers the ram 4 and the rod 5. The lifting mechanism 11 is, for example, a hydraulic cylinder driven by compressed oil. The lifting mechanism 11 may be, for example, a hydraulic cylinder driven by compressed liquid other than oil. The lifting mechanism 11 may be, for example, an air cylinder driven by compressed air.

[0023] A workpiece W is placed on the lower die 9. During hammer forging, an upper die 8 attached to a descending ram 4 collides with the workpiece W. When the workpiece W collides with the upper die 8 and is sandwiched between the lower die 9 and the upper die 8, the workpiece W is forged (for example, hot forged).

[0024] The hammer forging device 100 of this embodiment further includes ram position sensors 1, 2 and a bracket 3. The ram position sensors 1, 2 detect separation distances L1 (FIG. 2), L2 (FIG. 3) between the side surfaces of the ram 4 and the ram position sensors 1, 2, which change as the ram 4 is raised and lowered by the lifting mechanism 11. The ram position sensors 1, 2 constantly detect the separation distances L1, L2.

[0025] Each of the ram position sensors 1, 2 is supported by a bracket 3. Each of the ram position sensors 1, 2 is attached to a frame 6 via the bracket 3. Each of the ram position sensors 1, 2 may be attached to a location other than the frame 6 by the bracket 3.

[0026] 3, the ram position sensors 1, 2 include a ram height sensor 1 and a ram backlash sensor 2. The ram height sensor 1 is used to detect the elevation position of the ascending and descending ram 4. The ram backlash sensor 2 is used to detect the degree of backlash of the ram 4.

[0027] As shown in Fig. 2, ram height sensor 1 is disposed facing the side surface of ram 4 with a gap therebetween. Ram height sensor 1 detects separation distance L1 between the side surface of ram 4 and ram height sensor 1. Ram height sensor 1 constantly detects separation distance L1. Ram height sensor 1 is, for example, an eddy current displacement sensor.

[0028] The ram 4 has a distance changer IS that changes the distance L1 between the side surface of the ram 4 and the ram height sensor 1 as the ram 4 rises and falls. The distance changer IS extends in the height direction of the ram 4. The ram height sensor 1 is disposed so as to face the distance changer IS with a gap therebetween. The distance changer IS is disposed so as to continue to face the ram height sensor 1 with a gap therebetween even when the ram 4 rises and falls.

[0029] The ram 4 has a slope IS, for example, on a side surface of the ram 4 as a separation distance changing portion IS. The slope IS is a surface that is inclined with respect to the ascending and descending direction of the ram 4. The separation distance between the side surface of the ram 4 and the ram height sensor 1 is the distance between the slope IS of the ram 4 and the ram height sensor 1. The slope IS extends in the vertical direction on the side surface of the ram 4 and is inclined in the vertical direction.

[0030] The inclined surface IS may be formed by attaching a swash plate 4b to the main body 4a of the ram 4. This makes it possible to easily form the inclined surface IS on the ram 4 by additionally attaching (retrofitting) the swash plate 4b to the main body 4a of the ram 4.

[0031] The swash plate 4b may be connected to the main body 4a by welding or may be attached with bolts and nuts. By connecting the swash plate 4b to the main body 4a by welding, it is easy to reduce the weight. Also, by attaching the swash plate 4b to the main body 4a with bolts and nuts, it is easy to detach and replace the swash plate 4b to the main body 4a.

[0032] The slope IS may be formed integrally with the main body 4a of the ram 4. In other words, the slope IS may be formed on the main body 4a of the ram 4 by directly machining the main body 4a. By forming the slope IS on the main body 4a of the ram 4 by directly machining it in this manner, it is possible to reduce the weight and make it less susceptible to damage due to the impact of hitting with the hammer.

[0033] The slope IS is inclined such that the distance L1 between the slope IS and the ram height sensor 1 decreases, for example, from the top to the bottom of the slope IS. Specifically, as shown in Fig. 5(A), the distance LT when the ram 4 is at the lowest lift position is the largest of the distances L1. Also, as shown in Fig. 5(B), the distance LB when the ram 4 is at the highest lift position is the smallest of the distances L1.

[0034] The inclination of the slope IS is not limited to the above. For example, the slope IS may be inclined so that the distance L1 between the slope IS and the ram height sensor 1 becomes smaller from the lower end to the upper end of the slope IS. In the cross-sectional view shown in Figure 2, the slope IS may extend linearly along a single straight line, or may extend in a curved straight line formed by combining multiple straight lines.

[0035] In addition, the inclined surface IS may extend in a curved shape in the cross-sectional view shown in Fig. 2. In the cross-sectional view shown in Fig. 2, the inclined surface IS may extend in a curved shape having a single curvature, or in a curved shape combining a plurality of curvatures. In addition, the inclined surface IS may extend along a line combining a straight line and a curved line.

[0036] 3, the ram displacement sensor 2 is disposed so as to face the side surface of the ram 4 with a gap therebetween. The ram displacement sensor 2 detects a distance L2 between the side surface of the ram 4 and the ram displacement sensor 2.

[0037] The ram backlash sensor 2 has a front-rear backlash sensor 2a and a left-right backlash sensor 2b. The front-rear backlash sensor 2a is used to detect the degree of backlash in the front-rear direction of the ram 4. The front-rear backlash sensor 2a is arranged to face, with a gap between it and the front or rear surface, which is a side surface of the ram 4. The left-right backlash sensor 2b is used to detect the degree of backlash in the left-right direction of the ram 4. The left-right backlash sensor 2b is arranged to face, with a gap between it and the left or right surface, which is a side surface of the ram 4. Each of the front-rear backlash sensor 2a and the left-right backlash sensor 2b is, for example, an eddy current displacement sensor.

[0038] The ram 4 has a flat surface on its side. The ram 4 has a flat surface on at least one of its front and rear surfaces and at least one of its left and right surfaces. The flat surface on the side surface of the ram 4 extends in the direction in which the ram 4 rises and falls (the up-down direction) and is not inclined.

[0039] The distance between the side of the ram 4 and the ram gap sensor 2 is the distance between the flat surface of the ram 4 and the ram gap sensor 2. The front-rear gap sensor 2a is disposed so as to face the flat surface of the front or rear surface of the ram 4 with a gap therebetween. The front-rear gap sensor 2a is disposed so as to continue to face the flat surface of the front or rear surface of the ram 4 with a gap therebetween even when the ram 4 moves up or down. The front-rear gap sensor 2a detects the distance LC between the front-rear gap sensor 2a and the flat surface of the ram 4. The front-rear gap sensor 2a constantly detects the distance LC.

[0040] The left / right backlash sensor 2b is disposed so as to face, with a gap between it and the plane of the left or right surface of the ram 4. The left / right backlash sensor 2b is disposed so as to continue to face, with a gap between it and the plane of the left or right surface of the ram 4, even when the ram 4 moves up or down. The left / right backlash sensor 2b detects the separation distance LD between the left / right backlash sensor 2b and the plane of the ram 4. The left / right backlash sensor 2b constantly detects the separation distance LD.

[0041] <Forging operation of the hammer forging device 100>

[0042] Next, the forging operation of the hammer forging device 100 in this embodiment will be described with reference to FIGS.

[0043] Fig. 4 is a front view showing a state in which the ram is raised in the hammer forging device of Fig. 1. Fig. 5 is a diagram showing the lower limit position (A) and upper limit position (B) of the ram to explain the distance between the ram and the ram height sensor, and a diagram showing the lower limit position (C) and upper limit position (D) of the ram to explain the distance between the ram and the ram gap sensor.

[0044] As shown in Figures 1 and 4, the ram 4 is raised and lowered by driving the lifting mechanism 11. When the ram 4 reaches its upper limit position as shown in Figure 4, the upper die 8 is positioned above and away from the lower die 9. In this state, the distance L1 between the inclined surface IS and the ram height sensor 1 is at its minimum value LB as shown in Figure 5(B). In this state, the workpiece W is placed on the lower die 9 by an operator or an automatic machine.

[0045] From this state, the lifting mechanism 11 is driven to lower the ram 4, moving it from the upper limit position to the lower limit position. When the ram 4 reaches the lower limit position, the upper die 8 collides with the workpiece W from above, as shown in Fig. 1. This causes the workpiece W to be sandwiched between the lower die 9 and the upper die 8, and forging (e.g., hot forging) of the workpiece W is performed. When the ram 4 reaches the lower limit position, the distance L1 between the inclined surface IS and the ram height sensor 1 reaches a maximum value LT, as shown in Fig. 5(A).

[0046] When the ram 4 moves up and down between the upper limit position and the lower limit position, the ram height sensor 1 always faces the side surface (slope IS) of the ram 4. Also, as described above, the separation distance L1 between the ram height sensor 1 and the side surface (slope IS) of the ram 4 changes depending on the height position of the ram 4. Therefore, by detecting the separation distance L1 between the ram height sensor 1 and the side surface (slope IS) of the ram 4, the height position of the ram 4 can be determined from the separation distance L1.

[0047] Furthermore, when the ram 4 moves up and down between the upper limit position and the lower limit position, the ram gap sensors 2a, 2b always face the side surface (flat surface) of the ram 4. Furthermore, the distances LC, LD between the ram gap sensors 2a, 2b and the side surface (flat surface) of the ram 4 do not basically change depending on the height position of the ram 4, as described above. For this reason, by detecting the distances LC, LD between the ram gap sensors 2a, 2b and the side surface (flat surface) of the ram 4, it is possible to determine that there is backlash in the ram 4 if there is a change in the distances LC, LD. Furthermore, the degree of backlash in the fore-and-aft direction of the ram 4 can be determined from the degree of change in the distance LC.

[0048] If the separation distance LC (Fig. 3) changes, it can be determined that there is backlash in the front-to-rear direction of the ram 4. If the separation distance LD (Fig. 3) changes, it can be determined that there is backlash in the left-to-right direction of the ram 4. Furthermore, the degree of backlash in the left-to-right direction of the ram 4 can be determined from the degree of change in the separation distance LD.

[0049] <Configuration of a status monitoring system for a hammer forging machine>

[0050] Next, the configuration of the state monitoring system for the hammer forging device in this embodiment will be described with reference to Figs.

[0051] Fig. 6 is a diagram showing a configuration of a state monitoring system for a hammer forging device 100 in one embodiment of the present disclosure. As shown in Fig. 6, the state monitoring system for a hammer forging device in this embodiment includes the hammer forging device 100, a hydraulic supply source 21, a directional control valve 22, a valve driver 23, a hammer controller 24, a sensor controller 30, an alarm device 25, and a display 26.

[0052] The ram position sensors 1 and 2 detect the distances L1 and L2 between the ram position sensors 1 and 2 and the side surfaces of the ram 4 and output the distances L1 and L2 to the sensor controller 30.

[0053] The sensor controller 30 monitors the state of the hammer forging device 100 based on the separation distances L1, L2 acquired from the ram position sensors 1, 2. The sensor controller 30 calculates the height position of the ram 4 based on, for example, a detection signal (signal indicating the separation distance L1) detected by the ram height sensor 1. The sensor controller 30 calculates the degree of backlash of the ram 4 in at least one of the front-rear and left-right directions based on, for example, a detection signal (signal indicating the separation distance L2) detected by the ram backlash sensor 2.

[0054] The sensor controller 30 determines whether or not there is an abnormal impact by the ram 4 based on, for example, the calculated change in the height position of the ram 4. The sensor controller 30 determines whether or not there is an abnormal backlash of the ram 4 based on, for example, the calculated degree of backlash of the ram 4.

[0055] The sensor controller 30 outputs signals relating to the calculation results of the height position of the ram 4, the calculation results of the degree of backlash, the determination results of the presence or absence of an abnormal impact, and the determination results of the presence or absence of a backlash abnormality to the hammer controller 24, the alarm device 25, and the display 26. This makes it possible to display the height position of the ram 4, the degree of backlash, the presence or absence of an abnormal impact, the presence or absence of a backlash abnormality, etc. on the display 26. In addition, when an abnormal impact or a backlash abnormality occurs, the alarm device 25 can notify the fact.

[0056] Further, the hammer controller 24 outputs a command to the valve driver 23 to control the operation of the lifting mechanism 11 based on a command from the sensor controller 30. The valve driver 23 controls the opening and closing operation of the directional control valve 22 based on a command from the hammer controller 24.

[0057] The directional control valve 22 controls the flow direction and supply speed of the hydraulic oil supplied from the hydraulic supply source 21 to the lifting mechanism 11. The extension and contraction speed of the hydraulic cylinder, which is the lifting mechanism 11, is controlled by switching the flow direction of the hydraulic oil supplied from the directional control valve 22. In addition, the extension and contraction speed of the hydraulic cylinder, which is the lifting mechanism 11, is controlled by adjusting the supply speed of the hydraulic oil supplied from the directional control valve 22.

[0058] When the sensor controller 30 determines that an abnormal impact or a rattle abnormality has occurred as described above, the operation of the lifting mechanism 11 can be stopped.

[0059] Each of the sensor controller 30 and the hammer controller 24 includes a processor, a main memory, and a storage. The processor is, for example, a CPU (Central Processing Unit). The main memory includes, for example, a non-volatile memory such as a ROM (Read Only Memory) and a volatile memory such as a RAM (Random Access Memory). The sensor controller 30 and the hammer controller 24 may be separate controllers or may be integrated controllers.

[0060] Each of the sensor controller 30 and the hammer controller 24 may be mounted on the hammer forging apparatus 100, or may be disposed separately outside the hammer forging apparatus 100. When each of the sensor controller 30 and the hammer controller 24 are disposed separately outside the hammer forging apparatus 100, the sensor controller 30 may be wirelessly connected to the alarm device 25 and the display 26, etc., and the hammer controller 24 may be wirelessly connected to the valve drive unit 23, etc. Each of the sensor controller 30 and the hammer controller 24 may be stored in a server separate from the hammer forging apparatus 100.

[0061] Each of the sensor controller 30 and the hammer controller 24 reads the program stored in the storage, loads it into the main memory, and executes a predetermined process according to the program. The program may be distributed to each of the sensor controller 30 and the hammer controller 24 via a network.

[0062] <Sensor controller function block>

[0063] Next, the functional blocks of the sensor controller in this embodiment will be described with reference to FIG.

[0064] Fig. 7 is a diagram showing functional blocks of the sensor controller shown in Fig. 6. As shown in Fig. 7, the sensor controller 30 has a separation distance acquisition unit 30A, a state monitoring unit 30B, and an output control unit 30C.

[0065] The separation distance acquisition unit 30A acquires information about the separation distances L1, L2 between the ram position sensors 1, 2 and the side surfaces of the ram 4, which is output from the ram position sensors 1, 2. The separation distance acquisition unit 30A outputs the acquired information about the separation distances L1, L2 to the state monitoring unit 30B.

[0066] The state monitoring unit 30B monitors the state of the hammer forging device 100 based on the information on the separation distances L1, L2 acquired from the separation distance acquisition unit 30A. The state monitoring unit 30B outputs the monitoring result to the output control unit 30C.

[0067] The state monitoring unit 30B has a ram height position calculation unit 30D, an abnormal impact determination unit 30E, a rattle degree calculation unit 30F, a rattle abnormality determination unit 30G, and a memory 30H. The ram height position calculation unit 30D acquires information on the separation distances L1 and L2 from the separation distance acquisition unit 30A. The ram height position calculation unit 30D calculates the height position of the ram 4 based on the acquired information on the separation distances L1 and L2.

[0068] Here, the height position H of the ram 4 is calculated by the formula H=(L1-ΔLC) / tanθ. As shown in Fig. 5(A) and (B), L1 in the above formula is the distance between the inclined surface IS of the ram 4 and the ram position sensor 1, and changes depending on the height position of the ram 4. Also, ΔLC in the above formula is the amount of backlash from the normal position of the distance LC between the plane of the ram 4 and the front-rear backlash sensor 2a, as shown in Fig. 5(C) and (D). Also, ΔLC is the amount of backlash from the reference LC when the ram 4 is displaced to the right (displaced in the direction away from the front-rear backlash sensor 2a) in Fig. 5(C) and (D) is positive, and when the ram 4 is displaced to the left (displaced in the direction toward the front-rear backlash sensor 2a) is negative. Also, θ in the above formula is the angle between the ascending / descending direction of the ram 4 and the inclined surface IS, as shown in Fig. 5(A), and is the inclination angle of the inclined surface IS.

[0069] The ram height position calculation unit 30D outputs information regarding the calculated height position H of the ram 4 to the abnormal impact determination unit 30E. The abnormal impact determination unit 30E determines the presence or absence of an abnormal impact based on the obtained information regarding the height position H of the ram 4.

[0070] Here, the presence or absence of an abnormal impact is determined based on the change over time in the height position H of the ram 4, as shown in Figures 8 and 9. Specifically, as shown in Figure 8, a normal impact threshold value (dashed line) is set for each impact. This normal impact setting value is stored in memory 30H. When determining whether an abnormal impact has occurred, the abnormal impact determination unit 30E refers to the normal impact threshold value stored in memory 30H. The abnormal impact determination unit 30E uses an impact start signal as a trigger to constantly compare the actual impact waveform (solid line) with the normal impact threshold value.

[0071] In this comparison, if the actual impact waveform is observed to follow the normal impact threshold as shown in Fig. 8, the abnormal impact determination unit 30E determines that the impact is a normal impact. On the other hand, in the above comparison, if the actual impact waveform is observed to cross and exceed the normal impact threshold as shown in Fig. 9, the abnormal impact determination unit 30E determines that the impact is an abnormal impact.

[0072] The abnormal impact determination unit 30E outputs a signal indicating the determination result and a signal indicating the height position H of the ram 4 acquired from the ram height position calculation unit 30D to the output control unit 30C. The output control unit 30C outputs a signal indicating the determination result of the presence or absence of an abnormal impact and a signal indicating the height position H of the ram 4 to the hammer controller 24, the alarm device 25, and the display 26. As a result, the height position H of the ram 4, the presence or absence of an abnormal impact, etc. are displayed on the display 26. If an abnormal impact occurs, the alarm device 25 notifies the user of this. If an abnormal impact occurs, the hammer forging device 100 is controlled via the hammer controller 24, and for example, the operation of the lifting mechanism 11 is stopped.

[0073] The backlash degree calculation unit 30F also acquires information on the separation distances L1, L2 from the separation distance acquisition unit 30A. The backlash degree calculation unit 30F calculates the degree of backlash in at least one of the front-rear direction and the left-right direction of the ram 4 based on the acquired information on the separation distances L1, L2.

[0074] The degree of backlash in the front-rear direction of the ram 4 is calculated from the distance LC detected by the front-rear backlash sensor 2a, while the degree of backlash in the left-right direction is calculated from the separation distance LD detected by the left-right backlash sensor 2b.

[0075] The rattle degree calculation unit 30F outputs information relating to the calculated rattle degree to the rattle abnormality determination unit 30G. The rattle abnormality determination unit 30G determines whether or not there is a rattle abnormality based on the acquired information relating to the rattle degree of the ram 4.

[0076] Here, the presence or absence of an abnormal backlash of the ram 4 is determined based on the change in the backlash of the ram 4 relative to the height of the ram 4, as shown in Fig. 10. Specifically, as shown in Fig. 10, for the change in the backlash of the ram 4 relative to the height of the ram 4, a normal backlash threshold value (dashed line) corresponding to the height of the ram 4 is set. This normal backlash threshold value is stored in memory 30H. When determining the presence or absence of an abnormal backlash, the backlash abnormality determination unit 30G refers to the normal backlash threshold value stored in memory 30H. The backlash abnormality determination unit 30G uses an impact start signal as a trigger to constantly compare the actual backlash waveform (solid line) with the normal backlash threshold value.

[0077] In this comparison, if the actual rattle waveform is observed to be along the normal rattle threshold as shown in Fig. 10, the rattle abnormality determination unit 30G determines that the rattle is within the allowable range. On the other hand, in the above comparison, if the actual rattle waveform is observed to cross and exceed the normal rattle threshold as shown in Fig. 10, the rattle abnormality determination unit 30G determines that the rattle is a rattle abnormality.

[0078] In FIG. 10, the normal backlash threshold value changes depending on the height of the ram 4 because the gap between the ram 4 and the guide 7 may be set to be larger at the upper part and smaller at the lower part.

[0079] The backlash abnormality determination unit 30G outputs a signal indicating the determination result and a signal indicating the degree of backlash of the ram 4 acquired from the backlash degree calculation unit 30F to the output control unit 30C. The output control unit 30C outputs a signal indicating the determination result of the presence or absence of backlash abnormality and a signal indicating the degree of backlash of the ram 4 to the hammer controller 24, the alarm device 25, and the display 26. As a result, the degree of backlash of the ram 4, the presence or absence of backlash abnormality, etc. are displayed on the display 26. If a backlash abnormality occurs, the alarm device 25 notifies the user of this. If a backlash abnormality occurs, the hammer forging device 100 is controlled via the hammer controller 24, and for example, the operation of the lifting mechanism 11 is stopped.

[0080] <Method for monitoring the condition of a hammer forging device>

[0081] Next, a method for monitoring the state of the hammer forging device in this embodiment will be described with reference to FIGS.

[0082] 11 and 12 are a first flow chart and a second flow chart, respectively, showing a state monitoring method for a hammer forging device in one embodiment of the present disclosure. As shown in Fig. 11, in a hammer forging device 100, a workpiece W is placed on a lower die 9. In this state, an operator performs an operation to start striking. As a result, the lifting mechanism 11 starts to operate, and the ram 4 descends.

[0083] The ram position sensors 1 and 2 detect separation distances L1 and L2 between the ram position sensors 1 and 2 and the side surfaces of the ram 4. The ram position sensors 1 and 2 output information relating to the detected separation distances L1 and L2 to the sensor controller 30. The separation distance acquisition unit 30A of the sensor controller 30 acquires information relating to the separation distances L1 and L2 output from the ram position sensors 1 and 2 (step S1).

[0084] The separation distance acquisition unit 30A outputs information related to the acquired separation distances L1, L2 to the state monitoring unit 30B. The state monitoring unit 30B monitors the state of the hammer forging device 100 based on the information related to the separation distances L1, L2 acquired from the separation distance acquisition unit 30A (step S2). The state monitoring unit 30B outputs the monitoring result to the output control unit 30C.

[0085] Based on the monitoring result, the output control unit 30C controls devices such as the lifting mechanism 11, the alarm device 25, and the display 26 (step S3).

[0086] Next, an example of step S2 will be described separately for calculation of the height position of the ram 4 shown in FIG. 11 and calculation of the degree of backlash of the ram 4 shown in FIG.

[0087] 11, the ram height position calculation unit 30D of the sensor controller 30 acquires information on the separation distances L1 and L2 from the separation distance acquisition unit 30A. The ram height position calculation unit 30D calculates the height position of the ram 4 based on the acquired information on the separation distances L1 and L2 (step S2A).

[0088] The ram height position calculation unit 30D outputs information about the calculated height position H of the ram 4 to the abnormal impact determination unit 30E. The abnormal impact determination unit 30E determines whether or not an abnormal impact has occurred based on the obtained information about the height position H of the ram 4 (step S2B).

[0089] If it is determined that the impact is not abnormal, step S1 is repeated. On the other hand, if it is determined that the impact is abnormal, a signal indicating the determination result is output to the output control unit 30C. Based on the determination result that the impact is abnormal, the output control unit 30C controls devices such as the lifting mechanism 11, the alarm device 25, and the display 26 (step S3).

[0090] Specifically, the output control section 30C outputs signals related to the calculation result of the height position of the ram 4 and the determination result of the presence or absence of an abnormal impact to the hammer controller 24, the alarm device 25, and the display 26. As a result, the height position of the ram 4, the presence or absence of an abnormal impact, etc. are displayed on the display 26. If an abnormal impact occurs, the alarm device 25 notifies the user. If an abnormal impact occurs, the hammer forging device 100 is controlled via the hammer controller 24, and for example, the operation of the lifting mechanism 11 is stopped.

[0091] 12, the rattle degree calculation unit 30F of the sensor controller 30 acquires information on the separation distances L1 and L2 from the separation distance acquisition unit 30A. The rattle degree calculation unit 30F calculates the degree of rattle in at least one of the front-rear direction and the left-right direction of the ram 4 based on the acquired information on the separation distances L1 and L2 (step S2C).

[0092] The rattle degree calculation unit 30F outputs information relating to the calculated rattle degree to the rattle abnormality determination unit 30G. The rattle abnormality determination unit 30G determines the presence or absence of a rattle abnormality based on the acquired information relating to the rattle degree of the ram 4 (step S2D).

[0093] If it is determined that there is no backlash abnormality, step S1 is repeated. On the other hand, if it is determined that there is a backlash abnormality, a signal indicating the determination result is output to the output control unit 30C. Based on the determination result that there is a backlash abnormality, the output control unit 30C controls devices such as the lifting mechanism 11, the alarm device 25, and the display 26 (step S3).

[0094] Specifically, the output control unit 30C outputs signals related to the calculation result of the degree of backlash of the ram 4 and the determination result of the presence or absence of a backlash abnormality to the hammer controller 24, the alarm device 25, and the display 26. As a result, the degree of backlash of the ram 4, the presence or absence of a backlash abnormality, etc. are displayed on the display 26. If a backlash abnormality occurs, the alarm device 25 notifies the user of this. If a backlash abnormality occurs, the hammer forging device 100 is controlled via the hammer controller 24, and for example, the operation of the lifting mechanism 11 is stopped.

[0095] The method for monitoring the state of a hammer forging device in this embodiment is carried out as described above.

[0096] <Effects>

[0097] Next, the effects of this embodiment will be described.

[0098] 6, in this embodiment, the sensor controller 30 monitors the state of the hammer forging device 100 based on the separation distances L1, L2 between the ram position sensors 1, 2 and the side surface of the ram 4. By monitoring the state of the hammer forging device 100 in this way (the height position of the ram 4, the presence or absence of abnormal impact by the ram 4, the degree of backlash of the ram 4 in at least one of the front-rear and left-right directions, the presence or absence of abnormal backlash of the ram 4, etc.), it is possible to know, for example, wear of the guide 7 of the ram 4, the mounting state and wear state of the upper die 8 and the lower die 9, and it is possible to prevent breakdowns and maintain the hammer forging device 100.

[0099] Moreover, by knowing the state of the hammer forging device 100, it is also possible to know the quality of the forged workpiece W. Furthermore, by knowing the state of the hammer forging device 100, automation of the hammer forging device 100 becomes easier.

[0100] Furthermore, by additionally mounting (retrofitting) the ram position sensors 1, 2 and the sensor controller 30 to an existing hammer forging device, the hammer forging device 100 having the above-mentioned effects can be easily realized.

[0101] According to this embodiment, as shown in FIG. 7, the sensor controller 30 calculates the height position of the ram 4 when the ram 4 is raised and lowered based on the separation distances L1 and L2 detected by the ram position sensors 1 and 2. This makes it easy to obtain the height position of the ram 4. By monitoring the height position of the ram 4 during forging, it becomes easy to check the forging quality, it is possible to detect abnormal impacts in the automation of hammer forging, and it becomes possible to check whether the impact operation by the operator is appropriate in the manual operation of hammer forging. It also becomes easy to perform high-precision motion control of the ram 4 using the height position of the ram 4, which makes it easy to automate hammer forging.

[0102] 5(A) and 5(B), the ram 4 has a distance change part IS on the side of the ram 4, which changes the distance between the side of the ram 4 and the ram position sensor 1 when the ram 4 moves up and down. This makes it possible to easily calculate the height position of the ram 4 by detecting the distance between the ram position sensor 1 and the distance change part IS.

[0103] 5(A) and 5(B), the ram 4 has a slope IS on its side surface, which is the above-mentioned separation distance changer IS. This makes it possible to change the separation distance L1 between the side surface of the ram 4 and the ram position sensor 1 in the lifting / lowering direction using a simple shape such as a slope.

[0104] However, if the workpiece W bounces when the ram 4 strikes the workpiece W, the workpiece W may become displaced from the lower die 9. In this case, the operator must stop the operation of the hammer forging device 100 to correct the positional displacement of the workpiece W relative to the lower die 9. For this reason, it has been difficult to automate the hammer forging device 100.

[0105] In contrast, according to this embodiment, as shown in Figures 8 and 9, the sensor controller 30 determines whether or not there has been an abnormal impact by the ram 4 based on a change in the height position of the ram 4. Because abnormal impacts can be detected in this manner, the hammer forging device 100 can be automatically stopped when an abnormal impact is detected. This makes it easy to automate the hammer forging device 100.

[0106] Furthermore, in the hammer forging device 100, if the backlash of the ram 4 becomes large, the accuracy of the forged product deteriorates and the rod 5 breaks. The backlash of the ram 4 is usually managed by measuring the gap of the liner in the guide 7 with a gap gauge, but the measurement requires excessive effort. In particular, since the diameter of the rod 5 in a hydraulic hammer forging device is small, about 1 / 3 of the diameter of the rod 5 in an air hammer forging device, the backlash of the ram 4 has a large effect on the accuracy of the forged product and the breakage of the rod 5.

[0107] 7, in this embodiment, the sensor controller 30 calculates the degree of backlash in at least one of the front-rear and left-right directions of the ram 4 based on the separation distance L2 detected by the ram position sensor 2. This eliminates the need to use a gap gauge for measurement, and can prevent deterioration of the accuracy of the forged product and damage to the rod 5.

[0108] 5(C) and (D), in this embodiment, the distance L2 when detecting the degree of backlash of the ram 4 is the distance between the ram backlash sensor 2 and a flat surface on the side surface of the ram 4. This makes it possible to easily detect the backlash of the ram 4.

[0109] 10, the sensor controller 30 judges whether or not there is an abnormal backlash in the ram 4 based on the degree of backlash in the ram 4. This allows the user to recognize the abnormal backlash in the ram 4 in the hammer forging device 100. This makes it possible to prevent deterioration in the accuracy of the forged product and damage to the rod 5.

[0110] Furthermore, according to this embodiment, the ram position sensors 1 and 2 constantly detect the separation distances L1 and L2, making it possible to accurately monitor the state of the hammer forging device 100.

[0111] 3, the hammer forging device 100 has a bracket 3 that supports the ram position sensors 1, 2. This makes it possible for the ram position sensors 1, 2 to be supported by a frame 6 or the like via the bracket 3.

[0112] Furthermore, the hammer forging device 100 is installed on a vibration isolation device (not shown), and the entire hammer forging device 100 moves up and down significantly when striking. For this reason, if the height position of the ram 4 is calculated using ram position sensors 1 and 2 installed outside the hammer forging device 100, the relative position of the ram 4 with respect to the frame 6 will not be calculated correctly.

[0113] In contrast, in this embodiment, as shown in Fig. 3, the ram position sensors 1 and 2 are attached to the frame 6 via a bracket 3. This causes the ram position sensors 1 and 2 to vibrate in accordance with the vibration of the hammer forging device 100. Therefore, it is possible to accurately calculate the height position of the ram 4 relative to the frame 6 without being affected by the vibration of the entire hammer forging device 100 during striking.

[0114] Furthermore, the hammer forging device 100 generates a large impact when striking and causes flying debris, making the environment in which the hammer forging device 100 is used a harsh environment for sensors, etc. In this embodiment, eddy current displacement sensors are used for the ram position sensors 1 and 2 as sensors that can withstand such harsh environments. While these eddy current displacement sensors can withstand harsh environments, they have a disadvantage in that they have a short measurement distance. However, in this embodiment, the state of the hammer forging device 100 is monitored based on the separation distances L1 and L2 between the ram position sensors 1 and 2 and the side surface of the ram 4. Therefore, the disadvantage of eddy current displacement sensors, that is, the short measurement distance, does not pose a problem.

[0115] <Additional Notes>

[0116] The above-described embodiment includes the following technical ideas.

[0117] (Appendix 1) A condition monitoring system for a hammer forging device, comprising: a ram having a side surface; a lifting mechanism for lifting and lowering the ram; a ram position sensor that detects a distance between the ram and the side surface, which changes as the ram is raised and lowered by the lifting mechanism; a controller that monitors a condition of the hammer forging apparatus based on the distance between the ram position sensor and the side of the ram.

[0118] (Appendix 2) A condition monitoring system for a hammer forging device as described in Appendix 1, wherein the condition of the hammer forging device includes at least one selected from the group consisting of the height position of the ram, the presence or absence of abnormal impact by the ram, the degree of backlash of the ram in at least one of the forward / backward and left / right directions, and the presence or absence of abnormal backlash of the ram.

[0119] (Appendix 3) 2. A condition monitoring system for a hammer forging device as described in Appendix 1, wherein the controller calculates a height position of the ram during the raising and lowering of the ram based on the separation distance detected by the ram position sensor.

[0120] (Appendix 4) 4. A condition monitoring system for a hammer forging device as described in Appendix 3, wherein the ram has a distance changing portion on the side of the ram that changes the distance between the side of the ram and the ram position sensor when the ram rises and falls.

[0121] (Appendix 5) The ram has a bevel on the side surface; 5. A condition monitoring system for a hammer forging device as described in claim 4, wherein the inclined surface is the distance changing portion.

[0122] (Appendix 6) 6. A condition monitoring system for a hammer forging device as described in any one of Appendix 3 to Appendix 5, wherein the controller determines whether or not there is an abnormal impact by the ram based on a change in the height position of the ram.

[0123] (Appendix 7) The controller calculates the degree of backlash in at least one of the front-to-rear and left-to-right directions of the ram based on the separation distance detected by the ram position sensor.

[0124] (Appendix 8) The ram has a flat surface on the side, 8. A condition monitoring system for a hammer forging apparatus as described in claim 7, wherein the separation distance is the distance between the ram position sensor and the plane.

[0125] (Appendix 9) A condition monitoring system for a hammer forging device as described in Appendix 7 or Appendix 8, wherein the controller determines whether or not there is an abnormality in the backlash of the ram based on the degree of backlash of the ram.

[0126] (Appendix 10) 10. A condition monitoring system for a hammer forging device as described in any one of appendix 1 to appendix 9, wherein the ram position sensor constantly detects the separation distance.

[0127] (Appendix 11) A condition monitoring device for a hammer forging device having a ram having a side surface and a lifting mechanism for lifting and lowering the ram, a ram position sensor that detects a distance to the side surface of the ram that changes as the ram is raised and lowered by the lifting mechanism; and a controller that monitors the state of the hammer forging apparatus based on the distance between the ram position sensor and the side of the ram.

[0128] (Appendix 12) 12. A condition monitoring device for a hammer forging apparatus as described in claim 11, further comprising a bracket supporting the ram position sensor.

[0129] (Appendix 13) 1. A condition monitoring method for a hammer forging machine having a ram that has a side surface and moves up and down, comprising the steps of: detecting a distance between the ram and the side surface, the distance changing as the ram rises and falls; and monitoring a state of the hammer forging device based on the detected separation distance.

[0130] The embodiments disclosed herein should be considered to be illustrative and not restrictive in all respects. The scope of the present invention is defined by the claims, not the above description, and is intended to include all modifications within the meaning and scope of the claims. [Explanation of symbols]

[0131] 1, 2 ram position sensor, 2a front-rear backlash sensor, 2b left-right backlash sensor, 3 bracket, 4 ram, 4a main body, 4b swash plate, 5 rod, 6 frame, 6a machining space, 6b1 frame main body, 6b2 anvil, 7 guide, 8 upper die, 9 lower die, 10 lower die fixing base, 11 lifting mechanism, 21 hydraulic supply source, 22 directional control valve, 23 valve drive unit, 24 hammer controller, 25 alarm device, 26 display, 30 sensor controller, 30A separation distance acquisition unit, 30B status monitoring unit, 30C output control unit, 30D height position calculation unit, 30E abnormal impact determination unit, 30F backlash degree calculation unit, 30G backlash abnormality determination unit, 30H memory, 100 hammer forging device, IS inclined surface, W workpiece.

Claims

1. A condition monitoring system for a hammer forging device, comprising: a ram having a side surface; a lifting mechanism for lifting and lowering the ram; a ram position sensor that detects a distance between the ram and the side surface, which changes as the ram is raised and lowered by the lifting mechanism; a controller that monitors a condition of the hammer forging apparatus based on the distance between the ram position sensor and the side of the ram.

2. 2. A condition monitoring system for a hammer forging device as described in claim 1, wherein the condition of the hammer forging device includes at least one selected from the group consisting of the height position of the ram, the presence or absence of abnormal impact by the ram, the degree of backlash of the ram in at least one of the forward / backward and left / right directions, and the presence or absence of abnormal backlash of the ram.

3. 2. The condition monitoring system for a hammer forging device according to claim 1, wherein the controller calculates a height position of the ram during lifting and lowering of the ram based on the separation distance detected by the ram position sensor.

4. 4. A condition monitoring system for a hammer forging device as set forth in claim 3, wherein the ram has a distance changing portion on the side surface of the ram, whereby the distance between the side surface of the ram and the ram position sensor changes when the ram moves up and down.

5. The ram has a bevel on the side surface; 5. The condition monitoring system for a hammer forging device according to claim 4, wherein the inclined surface is the distance changing portion.

6. 4. The condition monitoring system for a hammer forging device according to claim 3, wherein the controller determines whether or not there is an abnormal impact by the ram based on a change in a height position of the ram.

7. 2. A condition monitoring system for a hammer forging device according to claim 1, wherein the controller calculates a degree of backlash of the ram in at least one of the front-rear direction and the left-right direction based on the separation distance detected by the ram position sensor.

8. The ram has a flat surface on the side, 8. The condition monitoring system for a hammer forging machine according to claim 7, wherein the separation distance is the distance between the ram position sensor and the plane.

9. 8. The condition monitoring system for a hammer forging device according to claim 7, wherein the controller determines whether or not there is an abnormal backlash of the ram based on the degree of backlash of the ram.

10. 2. The condition monitoring system for a hammer forging machine according to claim 1, wherein the ram position sensor constantly detects the separation distance.

11. A condition monitoring device for a hammer forging device having a ram having a side surface and a lifting mechanism for lifting and lowering the ram, a ram position sensor that detects a distance to the side surface of the ram that changes as the ram is raised and lowered by the lifting mechanism; and a controller that monitors the state of the hammer forging apparatus based on the distance between the ram position sensor and the side of the ram.

12. The apparatus for monitoring a condition of a hammer forging machine according to claim 11, further comprising a bracket supporting the ram position sensor.

13. 1. A condition monitoring method for a hammer forging machine having a ram that has a side surface and moves up and down, comprising the steps of: detecting a distance between the ram and the side surface, the distance changing as the ram rises and falls; and monitoring a state of the hammer forging device based on the detected separation distance.

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