Motor temperature monitoring and control system

Abstract

To provide a system for preventing burning of a motor by measuring the heat generation temperature of the motor itself continuously or at any time, and automatically stopping the operation of a vibratory hammer while there is a possibility of burning of the motor.SOLUTION: A temperature monitoring and control system for an electric motor of a vibratory hammer includes a control panel that controls an operation of the vibratory hammer, a temperature measuring instrument that includes a temperature sensor fixed to a housing of the electric motor and a transmitter for wireless communication, and a temperature management device that includes a communication device for wireless communication and controls the control panel while monitoring temperature data received from the temperature measuring instrument.SELECTED DRAWING: Figure 1

Description

[Technical Field]

[0001] The present invention relates to monitoring and controlling the temperature of an electric motor in a vibro hammer. [Background technology]

[0002] When operating an electric vibro hammer, it is necessary to prevent the motor from burning out due to heat generation. A conventional method for this has been to incorporate a thermal relay into the circuit of the control panel that controls the operation of the vibro hammer (see Patent Document 1). This trips by bending a plate when heat is generated due to overcurrent caused by overload or restraint, cutting off the power supply to the vibro hammer and protecting the motor from heat generation.

[0003] If an overload or overcurrent occurs in the electric motor, the thermal relay can temporarily stop the operation of the vibro hammer, and if the vibro hammer is restarted after being stopped and an overcurrent occurs again, the protective relay can also stop the operation of the vibro hammer. However, the heat generated by the overcurrent can accumulate in the electric motor and cause it to burn out, and what's more, if a worker is in a hurry to resume work after a stop, the thermal relay can be reset before enough time has passed and the vibro hammer can be restarted, which can also cause the electric motor to burn out. [Prior art documents] [Patent documents]

[0004] [Patent Document 1] Japanese Patent Application Publication No. 7-308019 Summary of the Invention [Problem to be solved by the invention]

[0005] Based on the above background, the object of the present invention is to provide a system that can continuously or at any time measure the heat generation temperature of the electric motor itself and prevent the electric motor from burning out by automatically stopping the operation of the vibro hammer while there is a possibility that the electric motor may burn out. [Means for solving the problem]

[0006] In order to solve the above-mentioned problems, the present invention has the following configuration. 1) The present invention is characterized in that 1. A temperature monitoring and control system for a vibro hammer electric motor, comprising: a control panel for controlling the operation of the vibro hammer; a temperature measuring device including a temperature sensor fixed to a housing of the electric motor and a transmitter for wireless communication; a temperature control device that includes a communication device for wireless communication and controls the control panel while monitoring the temperature data received from the temperature measuring device, The temperature control device controls the control panel to automatically stop operation of the vibro hammer when the temperature data exceeds a given upper limit value, and then maintains the stoppage of operation of the vibro hammer at least until the temperature data falls below a given lower limit value. 2) In the above embodiment, The upper limit value and the lower limit value can be changed by accessing the temperature control device from an information processing terminal; and The temperature data can be referenced continuously or at any time by accessing the temperature control device from an information processing terminal. 3) In the above embodiment, The radio wave intensity of the wireless communication and the remaining battery power of the transmitter can be referenced continuously or at any time by accessing the temperature control device from an information processing terminal. 4) In the above aspect, the control panel is provided with a vibro hammer operation control circuit having a self-holding circuit with a break contact of an electromagnetic relay, The automatic stopping of the operation of the vibro hammer and the maintenance of the stopped state of operation are carried out by controlling the application of voltage to the operation coil of the electromagnetic relay by the temperature control device. 5) In the above aspect, the temperature control device includes a delay timer; The voltage application to the operation coil continues until a certain time has elapsed since the temperature data fell below the lower limit value. 6) In the above embodiment, The temperature sensor has one or more indicator lights that indicate, by changing colors, when the temperature data exceeds the upper limit and falls below the lower limit. 7) In the above aspect, The indicator light may be further illuminated in a different color depending on the decrease in radio wave intensity of the wireless communication. [Effects of the Invention]

[0007] The system of the present invention makes it possible to measure the heat generation temperature of the electric motor continuously or at any time, and to prevent the electric motor from burning out by automatically stopping the operation of the vibro hammer during periods when there is a possibility that the electric motor may burn out. [Brief explanation of the drawings]

[0008] [Figure 1] FIG. 1 is a schematic diagram showing the components of the system according to the present invention. [Figure 2] FIG. 2(a) is a schematic front view of the vibro hammer, and (b) is a schematic side view showing a part of the vibro hammer. [Figure 3] FIG. 3 is a schematic diagram showing the functional configuration of the temperature control device in this system. [Figure 4] FIG. 4 shows a state transition diagram relating to the operable / inoperable states of the vibro hammer. [Figure 5] FIG. 5 is a schematic diagram showing a display example of the information processing terminal. DETAILED DESCRIPTION OF THE INVENTION

[0009] The system according to the present invention will be described below with reference to the drawings. In each drawing, the same or similar components are basically designated by the same reference numerals. Furthermore, the description of the same or similar components already described in another embodiment or modification may be omitted.

[0010] This invention relates to a system for monitoring and controlling the temperature of the electric motor in an electric vibro hammer. A vibro hammer is a device that generates a vertical vibration force by rotating a pair of eccentric weights in the same phase in opposite directions, and uses this vertical vibration to drive and extract piles or sheet piles.

[0011] 1 is a schematic diagram showing an example of the components of a system according to the present invention. A vibro hammer 10 is used by being suspended by a crane (not shown). The power supply to the vibro hammer 10 is controlled by a control panel electrically connected to a power source such as a generator G.

[0012] The vibro hammer 10 has a vibration exciter 12 at its center that generates the vibration force (see Figure 2(a)), which applies vibration to piles, sheet piles, and steel pipe piles clamped by a chuck 13 shown in the figure. To reduce the transmission of vibration from the vibration exciter 12 to the lifting device 16, a hanger 15 is connected to the vibration exciter 12 via a damper 14. An eccentric weight is placed at the bottom inside the vibration exciter 12, and an electric motor 17 is placed above it. In Figure 2(a), the housing 11 of the electric motor 17 can be seen bulging out in an arc shape from the vibration exciter.

[0013] The system of the present invention has a temperature measuring device 2 in addition to the configuration of this conventional vibro hammer 10. The temperature measuring device 2 mainly comprises a temperature sensor 21, a transmitter 22 that transmits temperature data obtained by the temperature sensor 21 to the outside as a signal, and a conductor 23 that connects them. Although it is possible to use a resistance thermometer as the temperature sensor 21, it is preferable to use a thermocouple, which is space-saving, relatively inexpensive, and has a fast response.

[0014] A temperature sensor such as a thermocouple 21 is installed outside or inside the housing 11 of the electric motor 17 to measure the temperature of the electric motor 17. If the temperature sensor is installed inside, there is a possibility that it may interfere with other parts, so it is preferable to install the temperature sensor outside the housing 11.

[0015] Fig. 2(b) is a schematic side view of the vibro hammer 10 shown in Fig. 2(a) when the range of the double-chain line P-P' is viewed from the direction of arrow A. Fig. 2(b) shows an example of the installation location of the thermocouple 21, and the thermocouple 21 is fixedly installed by adhesive or the like on the outside of the housing 11 of the electric motor 17, which can be seen in the figure. The thermocouple 21 and the transmitter 22 are connected by a conductor 23 for sending and receiving signals.

[0016] It is preferable to install the transmitter 22 on the hanger 15 where the vibrations generated by the vibrator 12 are reduced, rather than on the housing 11 of the electric motor 17. The transmitter 22 may have a function of converting the electromotive force measured by the thermocouple 21 into temperature data. In that case, the conductor 23 is made of a compensating conductor having substantially the same thermoelectromotive force characteristics as the thermocouple 21. The transmitter 22 may receive power from the control panel 5 via a transformer or the like, but it is preferable to provide a battery and configure it so that there are no wiring other than the conductor connected to the thermocouple 21.

[0017] The system of the present invention has a temperature control device 6 in addition to the conventional configuration having a vibro hammer 10 and a control panel 5. The temperature control device 6 is a computing device (computer) equipped with a board that realizes the functions of the system according to the present invention, and is equipped with a communication device 7 for wireless communication, and controls the control panel 5 while monitoring the temperature data received from the temperature measuring device 2. The temperature control device 6 records the temperature data received from the temperature measuring device 2 in a storage medium such as a hard disk or flash memory that it owns.

[0018] This wireless communication can also be configured as wired communication, but since the distance between the vibro hammer 10 and the control panel 5 can be several tens of meters, wireless communication is preferable when considering how to handle cables at the work site.

[0019] Temperature data is transmitted from the temperature measuring device 2 to the temperature control device 6 continuously, or optionally in response to a request from the temperature control device 6 to the temperature measuring device 2. Based on this temperature data, the temperature control device 6 can constantly monitor the temperature of the motor 17.

[0020] The upper limit of the temperature that is permitted when the electric motor 17 is operating is set or stored in the temperature control device 6. This upper limit is not the actual maximum allowable temperature of the electric motor 17, but is a value that is set appropriately taking into consideration the thermal conductivity of the housing 11 and the distance between the electric motor 17 and the temperature sensor, etc. The temperature control device 6 continues to compare real-time temperature data with the upper limit, and when the temperature data exceeds this upper limit, it controls the control panel to automatically stop the power supply to the vibro hammer 10, automatically stopping the operation of the vibro hammer 10.

[0021] The temperature at which restarting of the electric motor 17 is permitted is set or stored as a lower limit in the temperature control device 6. After automatically stopping the operation of the vibro hammer 10 as described above, the temperature control device 6 continues to compare the real-time temperature data with the lower limit, and maintains the state in which power supply to the vibro hammer 10 is disabled until the temperature data falls below this lower limit; in other words, it controls the control panel 5 so that the operation of the vibro hammer 10 remains stopped.

[0022] An example of a configuration for monitoring temperature data and controlling the control panel to either cut or maintain power to the vibro hammer 10 is described below. An electromagnetic relay break contact (normally closed contact) is added to the operation control circuit (particularly the self-holding circuit) of the vibro hammer 10 in the control panel 5, and the voltage applied to the operating coil of that electromagnetic relay is controlled by the circuit board of the temperature control device 6. When the temperature data of the electric motor 17 exceeds the upper limit value, voltage is applied to the operating coil of the electromagnetic relay, the break contact opens, i.e., the self-holding circuit opens, and the power supply to the vibro hammer 10 stops.

[0023] Thereafter, the supply of power to the vibro hammer 10 continues to be stopped by continuing to apply a voltage to the operating coil of the electromagnetic relay from the circuit board of the temperature control device 6 until the temperature data of the electric motor 17 falls below the lower limit value. At this time, a delay timer can be provided on the circuit board of the temperature control device 6 so that voltage application to the operation coil continues until a certain time has elapsed after the temperature of the electric motor 17 falls below the lower limit. In this case, when the temperature of the electric motor 17 falls below the lower limit and the delay timer counts up (or down) to the set value, the application of voltage from the circuit board of the temperature control device 6 to the operation coil of the electromagnetic relay stops, and as a result, the self-holding circuit described above closes, enabling power supply to the vibro hammer 10.

[0024] This configuration makes use of the configuration of the existing control panel 5 that controls the power supply to the vibro hammer 10, and can be easily applied to the existing configuration.

[0025] As a result, even if the thermal relay is reset, the operation of the vibro hammer cannot be resumed unless the temperature of the motor itself falls below the lower limit, so the motor can be protected from burning out due to the operator manually restarting work, etc. In this system, by measuring the temperature of the motor 17 itself, if heat generated by an overcurrent has accumulated in the motor 17, the vibro hammer 10 can be automatically stopped, preventing the motor 17 from burning out in such cases. Based on temperature data obtained through real-time temperature monitoring, the vibro hammer 10 is reliably protected from burnout of the electric motor 17 due to heat generation.

[0026] The system may have an indicator light 8 (see FIG. 1) so that a worker at the work site can visually check the state of the electric motor 10 and therefore whether the vibro hammer 10 is ready to operate. The system may have only one indicator light that emits multiple colors, or may have as many indicator lights as required that emit specific colors as shown in FIG. 1.

[0027] For example, the indicator light may be lit blue to indicate that the vibro hammer 10 is in operation or ready to operate, and red to indicate that the vibro hammer 10 is in an inoperable state.

[0028] A decrease in radio wave strength in wireless communication between the temperature measuring device 2 and the temperature control device 6 may cause the system to not operate properly, and may result in inadequate protection against burnout of the motor 17. Therefore, to let workers at the work site know of the decrease in radio wave strength, it can be made visually identifiable, for example, by turning on a yellow indicator light.

[0029] The indicator light 8 is electrically connected to the temperature control device 6, and the temperature control device 6 controls the on / off of the indicator light 8. The indicator light 8 is controlled in conjunction with the temperature monitoring performed by the temperature control device 6.

[0030] The temperature control device 6 is a computer that executes a program to realize the functions of this system. Figure 3 shows a schematic diagram of the functions provided on the board of the temperature control device 6. The temperature control device 6 has three main functions: a processing unit 31, a storage unit 32, and a communication unit 36. The communication unit 36 ​​performs wireless communication to receive temperature data measured by the temperature measuring device 2. The storage unit 32 writes and records the temperature data acquired by the processing unit 31 via the communication unit 36 ​​in a storage medium such as a hard disk or flash memory, and manages the temperature data. The recorded temperature data can be read by the processing unit 31.

[0031] The processing unit 31 mainly comprises an indicator light control unit 33, a temperature monitoring unit 34, and a control panel control unit 35. The temperature monitoring unit 34 compares the temperature data with the above-mentioned upper and lower limit values, and notifies the control panel control unit 35 when the temperature data exceeds the upper limit value, or when the temperature data subsequently falls below the lower limit value. Based on the comparison result, the control panel control unit 35 controls the application of voltage to the operating coil of an electromagnetic relay provided in an operation control circuit provided in the control panel 5, and indirectly controls the electric motor of the vibro hammer 10. Based on the comparison result, the indicator light control unit 33 controls the color of the light that is lit by the indicator light control unit 33. The communication unit 36 ​​also provides a function for wireless communication with the information processing terminal J via a network.

[0032] Figure 4 shows a state transition diagram regarding the operable / unoperable state of the vibro hammer 10 corresponding to the temperature data and the display of the indicator light 8 when the temperature control device 6 compares the temperature data with upper and lower limit values, automatically stops the vibro hammer 10 via the control panel 5, and controls the on / off of the indicator light 8.

[0033] When the system according to the present invention is started up by supplying power to the temperature control device 6 and the control panel 5 (S1), the system enters an operable state (S2) in which power can be supplied to the vibro hammer 10. At that time, the temperature control device 6 instructs the indicator light 8 to light up blue (S3). Since the actual start of operation of the vibro hammer 10 is performed manually by an operator, this operable state (S2) means that the operator can start operation of the vibro hammer 10.

[0034] The temperature control device 6 refers to the temperature data continuously sent from the temperature measuring device 2 in real time, monitors whether the temperature T exceeds the upper limit value (S4), and maintains an operable state (state in which power can be supplied) (L1) regardless of whether the vibro hammer 10 is actually operating or not, as long as the upper limit value is not exceeded. When it detects that the temperature T has exceeded the upper limit value, it stops the power supply to the vibro hammer 10 via the control panel 5 (S5) and instructs the indicator light 8 to light up red (S6).

[0035] Next, the temperature control device 6 maintains the vibro hammer 10 in an inoperable state (power supply disabled state) (L2) until the temperature T falls below the lower limit (S7), and during this time the indicator light 8 continues to light up red. As the operation of the electric motor 17 continues to be stopped, the temperature drops, and when the temperature control device 6 detects that the temperature T has fallen below the lower limit, it transitions to an operable state (a state in which power can be supplied) (S8) and instructs the indicator light 8 to light up blue (S9). When the transition to this state occurs, the operator can manually restart the operation of the vibro hammer.

[0036] After the transition to the operable state (power supply possible state), the state transitions again to a state (S4) in which it is determined whether the temperature T exceeds the upper limit (L3).

[0037] During this state transition, the temperature control device 6, for example, checks the radio wave strength at regular intervals, and when it detects that the radio wave strength has weakened, it instructs the indicator light 8 to turn yellow (not shown). This check of the radio wave strength may be done at regular intervals, or may be done at a point where a loop (L1, L2, L3) occurs, or the process may be interrupted when the radio wave strength decreases, causing the indicator light 8 to turn yellow.

[0038] The system has an indicator light 8, which allows the worker to visually check the temperature state of the motor 17. For example, even if the automatic stop is delayed for some reason even though the temperature of the motor 17 exceeds the upper limit, the worker can stop the vibro operation himself, which may prevent the motor 17 from burning out. In addition, since it is clear at a glance that the temperature of the motor 17 has fallen below the lower limit, it is also easy to determine the timing to restart operation.

[0039] The operator manually restarts the operation of the vibro hammer. This is to prevent accidents caused by an unexpected restart of the vibro hammer 10 by not automatically restarting the operation even if the temperature of the electric motor falls below the lower limit.

[0040] The system may also be configured so that temperature data can be accessed continuously or at will on an information processing terminal J such as a smartphone, tablet, or laptop. The information processing terminal J can access the temperature data received from the thermometer side device 2 in real time by communicating with the temperature monitoring unit 6. The system may also be configured so that past temperature data recorded by the temperature control device 6 can be accessed.

[0041] Furthermore, the administrator may be able to change the settings of the upper and lower limit values ​​from the information processing terminal J. On-site workers may only check the temperature data using the information processing terminal J, and the administrator may also be able to change the settings of the upper and lower limit values ​​according to the on-site conditions.

[0042] Furthermore, this system may be configured so that information relating to the radio wave intensity of wireless communication and the remaining battery level of the transmitter 22 is received from the temperature control device 6 continuously or at any time, and can be referenced by the information processing terminal J.

[0043] 5 shows an example of a display on the screen of the information processing terminal J. In this way, the real-time temperature of the electric motor 17 can be confirmed on the screen of the information processing terminal J, and the set upper and lower limits can also be confirmed. The upper and lower limits can also be reset by entering numbers as appropriate before or during work and tapping Send. The wireless communication signal status may be expressed in three states, for example, "connected," "not connected," and "poor connection." Figure 5 shows the "connected" state, indicating that the signal strength has not decreased.

[0044] This system can be easily introduced into existing equipment, that is, it can be introduced in addition to the conventional system using a thermal relay.

[0045] Each component is provided for convenience of explanation, and the scope of rights is not limited to the configuration shown in the specification or drawings, as long as it is encompassed by the claims. For example, a temperature control device can be placed inside a control panel and realized as an integrated component, in which case the control panel can be considered to realize each function. Even in this case, the system can still be introduced into a conventional configuration. Furthermore, the functions realized by the temperature control device can be realized by either software or circuitry (hardware).

[0046] The present invention has been described above with reference to the drawings showing embodiments of the present invention, but a combination of one or more configurations described in one embodiment with one or more configurations described in another embodiment is also included in one embodiment of the present invention as long as it is in line with the spirit of the present invention. Furthermore, various further modifications are possible as long as they are in line with the spirit of the present invention, and these are also included in embodiments of the present invention. [Explanation of symbols]

[0047] 2 Temperature measuring instruments 5 Control Panel 6 Temperature control equipment 7. Communication Devices 8 Indicator Light 10 Vibro Hammer 11. Housing 12 Vibrator 13. Zipper 14 Damper 15 Hanger 16 Lifting equipment 17 Electric motor 21 Thermocouple (temperature sensor) 22 Transmitter 23 Conductor 31 Processing section 32 Storage section 33 Indicator light control unit 34 Temperature monitoring section 35 Control panel control section 36 Communications Department T temperature J Information processing terminal G Generator

Claims

1. 1. A temperature monitoring and control system for a vibro hammer electric motor, comprising: a control panel for controlling the operation of the vibro hammer; a temperature measuring device including a temperature sensor fixed to a housing of the electric motor and a transmitter for wireless communication; a temperature control device that includes a communication device for wireless communication and controls the control panel while monitoring the temperature data received from the temperature measuring device, The temperature control device controls the control panel to automatically stop operation of the vibro hammer when the temperature data exceeds a given upper limit value, and then maintains the stoppage of operation of the vibro hammer at least until the temperature data falls below a given lower limit value.

2. The upper limit value and the lower limit value can be changed by accessing the temperature control device from an information processing terminal; and 2. The system according to claim 1, wherein the temperature data can be referenced continuously or at any time by accessing the temperature control device from an information processing terminal.

3. 3. The system according to claim 2, wherein the radio wave intensity of the wireless communication and the remaining battery level of the transmitter can be referenced continuously or at any time by accessing the temperature control device from an information processing terminal.

4. the control panel is provided with a vibro hammer operation control circuit having a self-holding circuit with a break contact of an electromagnetic relay, The system described in any one of claims 1 to 3, characterized in that the automatic stopping and the maintenance of the stopped state of the vibro hammer operation are performed by controlling the voltage application to the operating coil of the electromagnetic relay using the temperature control device.

5. the temperature control device includes a delay timer; 5. The system according to claim 4, wherein the voltage application to the operation coil continues until a predetermined time has elapsed since the temperature data fell below the lower limit value.

6. The system of any one of claims 1 to 3, further comprising one or more indicator lights that indicate, by different colors, when the temperature data exceeds the upper limit and falls below the lower limit.

7. 7. The system of claim 6, wherein the indicator light changes color to indicate a decrease in radio wave strength of the wireless communication.

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