Electric lubricant dispenser, and method for dispensing lubricant from an electric lubricant dispenser.

Abstract

This invention provides a technology that can properly detect the presence of gas in the pump of an electric lubricant dispenser. [Solution] One aspect of the present disclosure provides an electric lubricant dispenser comprising a motor, a pump, a drive circuit, and a control circuit. The pump comprises a housing for containing lubricant and a reciprocating member. The control circuit performs predetermined processing based on the actual operating amount meeting predetermined requirements. The actual operating amount has a magnitude corresponding to the magnitude of a specific load applied to the motor. The specific load includes a first load based on pressure from the lubricant and does not include at least a portion of a second load based on the reciprocating motion of the reciprocating member itself.

Description

Technical Field

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[0003] , , , , The present disclosure relates to an electric lubricant supplier.

Background Art

[0002] Patent Document 1 discloses a grease discharge device including a pump. In this grease discharge device, the pump receives grease from a tank and discharges the grease.

Prior Art Documents

Patent Documents

Patent Document 1

Summary of the Invention

Problems to be Solved by the Invention

[0004] In a grease discharge device, air may be mixed into the grease in the pump. When air is mixed into the pump, appropriate discharge of the grease by the pump may be inhibited by the air. For example, the discharge amount of the grease may temporarily decrease or the grease may temporarily stop being discharged.

[0005] One aspect of the present disclosure aims to provide a technique capable of appropriately detecting that gas is mixed into a pump

Means for Solving the Problems

[0006] In the present disclosure, terms such as "first" and "second" are merely intended to distinguish elements from each other and are not intended to limit the order or number of the elements. Therefore, the first element may be referred to as the second element, and similarly, the second element may be referred to as the first element. In addition, the first element may be provided without the second element, and similarly, the second element may be provided without the first element. ​​​​​​

[0007] One aspect of this disclosure is the provision of an electric lubricant dispenser comprising a motor, a pump, a drive circuit, and a control circuit. The pump comprises a housing and a reciprocating member. The housing is configured to house a lubricant. The reciprocating member is configured to (i) be at least partially located within the housing, (i) repeatedly reciprocate in a first direction and a second direction in the opposite direction in response to the rotation of a motor, and (iii) discharge the lubricant from within the housing as the reciprocating member moves in the first direction.

[0008] The drive circuit is configured to drive the motor. The control circuit controls the drive circuit to rotate the motor. While the motor is running, the control circuit performs predetermined processing based on whether the actual operating amount meets predetermined requirements. The actual operating amount has a magnitude corresponding to the magnitude of a specific load. The specific load is included in the motor load, and the motor load is the load applied to the motor. The predetermined requirement indicates that gas is mixed in the housing.

[0009] The specified load includes the first load but does not include at least a portion of the second load. The first load is applied from the reciprocating member by the pressure the reciprocating member receives from the lubricant. The second load is applied from the reciprocating member by the reciprocating motion of the reciprocating member itself, independently of the aforementioned pressure.

[0010] An electric lubricant dispenser configured in this way can properly detect if gas is mixed into the containment section (i.e., inside the pump). Another aspect of this disclosure is a method for dispensing lubricant from an electric lubricant dispenser, The motor moves a reciprocating member back and forth to discharge the lubricant from the housing, During motor operation, a predetermined process is performed based on the fact that the actual operating amount, which is a certain amount corresponding to the magnitude of a specific load among the motor loads applied to the motor, satisfies predetermined requirements indicating that gas is mixed into the housing. This provides a method for providing this.

[0011] The specific load includes a first load applied by the reciprocating member as the reciprocating member receives pressure from the lubricant, and does not include at least a portion of a second load applied by the reciprocating member as a result of the reciprocating member moving back and forth independently of the pressure.

[0012] This method allows for the proper detection of gas contamination in the storage compartment of an electric lubricant dispenser. [Brief explanation of the drawing]

[0013] [Figure 1] This is a perspective view of the electric lubricant dispenser according to the first embodiment. [Figure 2] This is a central longitudinal cross-section of an electric lubricant dispenser. [Figure 3] This is an explanatory diagram illustrating how a plunger moves up and down due to the rotation of a motor. [Figure 4] This is a plan view of the control panel for an electric lubricant dispenser. [Figure 5] This is a circuit diagram showing the electrical configuration of an electric lubricant dispenser. [Figure 6] This is a functional block diagram of the control circuit in an electric lubricant dispenser. [Figure 7] This is an explanatory diagram for schematically illustrating the load and torque applied to a motor. [Figure 8] This is an explanatory diagram to schematically illustrate that the motor load includes the first to third loads. [Figure 9] This is an explanatory diagram showing an example of the operation of an electric lubricant dispenser under normal conditions and in a low-temperature environment. [Figure 10] This is an explanatory diagram showing an example of the operation of an electric lubricant dispenser under normal conditions and in a high-temperature environment. [Figure 11] This is an explanatory diagram showing an example of the operation of an electric lubricant dispenser under conditions of air entrapment and low temperature. [Figure 12] This is an explanatory diagram showing an example of the operation of an electric lubricant dispenser under conditions of air entrapment and high temperature. [Figure 13]It is an explanatory diagram illustrating the moving average of the load physical quantity in the air biting state and in a low-temperature environment. [Figure 14] It is an explanatory diagram illustrating the moving average of the load physical quantity in the normal state and in a high-temperature environment. [Figure 15] It is an explanatory diagram showing an example of setting the first current threshold. [Figure 16] It is a flowchart of the main process. [Figure 17] It is a flowchart of the process during stop. [Figure 18] It is a flowchart of the process during operation. [[ID=1�]] [Figure 19] It is a flowchart of the air biting detection process of the first embodiment. [Figure 20] It is a flowchart of the continuation determination process. [Figure 21] It is a flowchart of the air biting detection process of the second embodiment. [Figure 22] It is a flowchart of the air biting detection process of the third embodiment. [Figure 23] It is an explanatory diagram illustrating the first level and the second level of the load physical quantity in the air biting state and in a low-temperature environment. [Figure 24] It is an explanatory diagram illustrating the first level and the second level of the load physical quantity in the normal state and in a high-temperature environment. [Figure 25] It is a partial flowchart of the air biting detection process of the fourth embodiment. [Figure 26] It is a flowchart of the other part (continuation of FIG. 25) of the air biting detection process of the fourth embodiment. [Figure 27] It is a partial flowchart of the air biting detection process of the fifth embodiment. [Figure 28] It is a flowchart of the other part (continuation of FIG. 25) of the air biting detection process of the fifth embodiment. [Figure 29] It is a partial flowchart of the air biting detection process of the sixth embodiment. [Figure 30] It is a flowchart of the other part (continuation of FIG. 25) of the air biting detection process of the sixth embodiment. [Modes for carrying out the invention]

[0014] [1. Summary of Embodiments] One embodiment may provide an electric lubricant dispenser comprising at least one of the following: Feature 1: Motor. • Feature 2: Pump Feature 3: The pump has a housing. Feature 4: The storage compartment is configured to hold lubricant. Feature 5: The pump is equipped with a reciprocating member. Feature 6: The reciprocating member is located at least partially within the housing. Feature 7: The reciprocating member is configured to repeatedly reciprocate in a first direction and a second direction in the opposite direction in response to the rotation of the motor. Feature 8: The reciprocating member is configured to discharge lubricant from the housing as the reciprocating member moves in the first direction. Feature 9: Drive circuit. Feature 10: The drive circuit is configured to drive the motor. Feature 11: Control circuit. Feature 12: The control circuit is configured to control the drive circuit to rotate the motor (in other words, to perform the first action). Feature 13: The control circuit is configured to perform predetermined processing (in other words, execute a second operation) based on whether the actual operating amount meets predetermined requirements while the motor is running. Feature 14: The actual operating volume has a magnitude that corresponds to the size of the specific load. Feature 15: A specific load is part of the motor load. In other words, a specific load is included in the motor load. Feature 16: Motor load is the load applied to the motor. Feature 17: The specified requirement indicates that gas (or bubbles) is present in the containment area. Feature 18: The specific load includes the first load. Feature 19: The first load is applied from the reciprocating member by the reciprocating member receiving pressure from the lubricant. Feature 20: The specific load does not include at least a portion of the second load. Feature 21: The second load is applied from the reciprocating member by the reciprocating motion of the reciprocating member itself, regardless of the aforementioned pressure.

[0015] An electric lubricant dispenser having at least features 1 to 21 can properly detect the presence of gas in the containment. The motor is in the form of an electric motor. The motor may be configured to generate a driving force (or rotational driving force or driving torque). The reciprocating member directly receives the driving force of the motor. Alternatively, it may be configured to receive the power indirectly and be driven by that driving force.

[0016] The motor may be configured to (i) rotate in response to an electric current and (ii) output a drive torque corresponding to the current. The motor may receive an electric current from a drive circuit.

[0017] Examples of motors include DC motors, AC motors, and stepping motors. Examples of DC motors include brushless motors (or brushless DC motors) and brushed DC motors.

[0018] Examples of lubricants include liquid lubricants and semi-solid lubricants. Examples of liquid lubricants include lubricating oils. Examples of semi-solid lubricants include greases. That is, an example of an electric lubricant dispenser includes an electric grease gun.

[0019] Motor load is the load applied to the motor from outside the motor. Specific load is a part of the motor load. Motor load includes loads generated from reciprocating members and applied to the motor (hereinafter referred to as "pump load"). Pump load includes the first load and the second load. Specific load is a part of the pump load. Specific load may be defined as the pump load with at least a portion of the second load omitted. Almost all or all of the specific load may be the first load.

[0020] The first load may have a magnitude corresponding to the pressure. The first load may be applied by the reciprocating member by receiving pressure from the lubricant when the reciprocating member moves in the first direction (i.e., when discharging).

[0021] The second load is a load that arises independently of the pressure applied to the reciprocating member by the lubricant. The second load may also be defined as the load applied to the motor by the reciprocating member when the housing is open and there is no lubricant. Even simply moving the reciprocating member back and forth in the absence of lubricant in the housing requires torque from the motor due to mechanical factors (e.g., sliding resistance) of the reciprocating member and / or its surroundings. The load corresponding to that torque can be said to be the second load. Sliding resistance can arise from friction between the reciprocating member and other members in contact with it. Other members may include the inner wall of the housing that faces the reciprocating member.

[0022] The reciprocating member may be configured to reciprocate within a predetermined range of motion. The reciprocating member may be configured to move linearly (i.e., reciprocate along a straight line). The electric lubricant dispenser may include a converter that converts rotational motion into linear motion. The converter (i) is directly or indirectly connected to the motor and the reciprocating member, (ii) receives the rotation of the motor, and (iii) converts that rotation into the reciprocating motion of the reciprocating member. The converter may be one of several components that make up the pump.

[0023] The pump may be configured to supply lubricant to the housing as the reciprocating member moves in a second direction. The pump may have a discharge port that communicates with the housing. The lubricant may be discharged from the discharge port to the outside of the housing (and consequently to the outside of the pump, and further to the outside of the electric lubricant dispenser) as the reciprocating member moves in a first direction.

[0024] The lubricant may be contained (or filled) within the containment in any way. The containment may have an inlet for receiving the lubricant from outside the pump. The lubricant may flow into the containment through the inlet by pressure being applied to the inlet outside the pump. The containment may (i) have negative pressure in the containment as the reciprocating member moves in a second direction. (ii) The pump may be configured such that a negative pressure is generated, and the lubricant flows (i.e., is drawn) into the housing from outside the pump through the inlet.

[0025] A pump can include any form capable of discharging a lubricant by the reciprocating motion of a reciprocating member. A pump may be configured such that the volume within a housing changes due to the reciprocating motion of a reciprocating member, thereby discharging the lubricant. Examples of pumps include positive displacement pumps (more specifically, reciprocating pumps). Examples of reciprocating pumps include plunger pumps, piston pumps, and diaphragm pumps. Examples of reciprocating members include plungers, pistons, and diaphragms.

[0026] An example of a housing includes a chamber and a cylinder. In a diaphragm pump, the diaphragm constitutes part of the chamber. The drive circuit may include multiple switching elements connected to the motor. Examples of drive circuits include full-bridge and half-bridge circuits.

[0027] A full-bridge circuit may be connected to a three-phase motor. A three-phase motor has (i) three terminals configured to receive power, and (ii) is configured to rotate by the power received. The aforementioned brushless motor is a three-phase motor.

[0028] A full-bridge circuit may have six switching elements. Examples of the six switching elements include semiconductor switches and mechanical relays. Examples of semiconductor switches include field-effect transistors (FETs), bipolar transistors, insulated-gate bipolar transistors (IGBTs), thyristors, and solid-state relays (SSRs).

[0029] The six switching elements may include three high-side switches and three low-side switches. The three high-side switches are electrically connected to the positive terminal of the power supply and to the three terminals of the motor, respectively. The three low-side switches are electrically connected to the negative terminal of the power supply and to the three terminals of the motor, respectively. The three high-side switches may be arranged to conduct or interrupt the three positive-side current paths, respectively. The three positive-side current paths electrically connect the three terminals of the motor to the positive terminal of the power supply, respectively. The three low-side switches may be arranged to conduct or interrupt the three negative-side current paths, respectively. The three negative-side current paths electrically connect the three terminals of the motor to the negative terminal of the power supply, respectively.

[0030] Here, the state in which the containment is filled with lubricant and no gas is present is referred to as the normal state, and the state in which gas is present in the containment is referred to as the contaminated state. Under normal conditions, the first load increases significantly when the reciprocating member moves in the first direction, and decreases significantly or becomes zero when it moves in the second direction. On the other hand, under the contaminated condition, the first load when the reciprocating member moves in the first direction is lower than under normal conditions. In other words, the first load increases and decreases with each reciprocating movement of the reciprocating member. That is, the first load fluctuates periodically with one reciprocating movement of the reciprocating member as one cycle. Furthermore, the magnitude of this increase and decrease is smaller under the contaminated condition than under normal conditions.

[0031] Therefore, if the motor load does not include a second load, it is possible to determine whether or not gas is present in the housing based on the motor load (or the physical load quantity). This is because, in this case, the motor load can generally be largely, almost entirely, or entirely the first load. In other words, fluctuations in the motor load in this case can be considered as fluctuations in the first load.

[0032] However, in reality, torque is required just to move the reciprocating member back and forth, so the motor load includes a second load. Moreover, this second load can also fluctuate depending on the reciprocating movement of the member.

[0033] The second load is independent of the pressure from the lubricant. Therefore, the second load can fluctuate, for example, with each one-way movement of the reciprocating member. In other words, the second load can fluctuate periodically with one-way movement of the reciprocating member as one cycle. One-way movement means that the reciprocating member moves from the first end to the second end of its movement path, and that the reciprocating member moves from the second end to the first end. The first end is the end in the first direction of the movement path, and the second end is the end in the second direction of the movement path.

[0034] Therefore, determining whether or not gas is present in the containment based on the motor load is not easy, difficult, or impossible. In contrast, the control circuit equipped with the above feature 13 performs predetermined processing based on the fact that the actual operating amount satisfies predetermined requirements. The actual operating amount indicates the operating state of the electric lubricant dispenser and may include the amplitude of the filtered physical quantity described later, and the round-trip difference. The specific load includes the first load, while some or all of the second load is excluded. Therefore, the control circuit can appropriately determine the state of gas contamination in the containment section and operate appropriately according to the contamination state.

[0035] The specified requirements may indicate that there is a possibility of gas being present in the containment. That is, the actual operating amount satisfying the specified requirements may correspond to the presence of gas in the containment, or the possibility of gas being present in the containment. Alternatively, the statement "there is gas present in the containment" may itself encompass the meaning of "there is a possibility of gas being present in the containment."

[0036] The presence of gas in the containment may include (i) gas being present in the lubricant within the containment, (ii) gas being present in the discharge material that is about to be discharged by the reciprocating member, and / or (iii) gas being present in the containment without any lubricant.

[0037] The prescribed treatment may be any treatment that corresponds to the presence of gas in the containment. The prescribed treatment may also be a treatment that should be performed or is preferable to be performed when gas is present in the containment. When gas is present in the containment, the lubricant may not be discharged properly. Specifically, the amount of lubricant discharged may decrease or the lubricant may not be discharged at all. Therefore, the prescribed treatment may be a treatment that corresponds to a state in which the lubricant may not be discharged properly, that is, a treatment that should be performed or is preferable to be performed in that state. Examples of the prescribed treatment are described later.

[0038] In one embodiment, the control circuit may be integrated into a single electronic unit, a single electronic device, or a single circuit board. In one embodiment, the control circuit may be a combination of two or more electronic circuits, two or more electronic units, or two or more electronic devices, individually provided on or within the electric lubricant dispenser.

[0039] In one embodiment, the control circuit may comprise a microcomputer (or microcontroller or microprocessor), wired logic, application-specific integrated circuits (ASICs), application-specific general-purpose products (ASSPs), programmable logic devices (PLDs) (such as field-programmable gate arrays (FPGAs)), discrete electronic components, and / or a combination thereof.

[0040] In one embodiment, the electric lubricant dispenser may be handheld (in other words, portable). That is, the electric lubricant dispenser may have a grip configured to be held by the user of the electric lubricant dispenser. The electric lubricant dispenser may be used while the grip is held by the user.

[0041] One embodiment may include, in addition to or instead of, at least one of the features 1 to 21 described above, at least one of the following: Feature 22: The pump is equipped with a guide. Feature 23: The guide supports the reciprocating member so that it can move back and forth. Feature 24: The reciprocating member is configured to move along the guide.

[0042] The second load may include sliding loads. Sliding loads can arise from sliding resistance (or frictional resistance) between the reciprocating member and the guide. More than half, most, or all of the second load may consist of sliding loads. The greater the sliding resistance, the larger the proportion of the second load to the motor load. Therefore, it becomes difficult to detect gas contamination based on the motor load.

[0043] Furthermore, the reciprocating member and / or guide may be coated with a lubricant to reduce friction between them. In other words, the reciprocating member may be in contact with the guide via the lubricant. Note that the lubricant referred to here is different from a lubricant.

[0044] In this case, the second load (more specifically, the sliding load) can change with temperature. This is because, generally, the viscosity of lubricating oil changes with temperature. Specifically, the viscosity of lubricating oil generally decreases (i.e., softens) as the temperature rises and increases (i.e., hardens) as the temperature falls. Therefore, the second load decreases as the temperature rises and increases as the temperature falls. In other words, the proportion of the second load to the motor load changes with temperature. For this reason, it is difficult to accurately detect the presence of gas in the housing over a wide temperature range based on the motor load.

[0045] In contrast, since the specific load does not include at least a portion of the second load, the influence of the second load on the specific load (and consequently the actual operating amount) is reduced or eliminated. Therefore, an electric lubricant dispenser having at least features 1 to 24 can appropriately detect the presence of gas in the containment over a wide temperature range, even if sliding resistance occurs between the reciprocating member and the guide. In one embodiment, the reciprocating member may have a protrusion and the guide may have a groove. The protrusion may be fitted into the groove and be movable along the groove together with the reciprocating member in a first and second direction. Conversely, the guide may have a protrusion and the reciprocating member may have a groove.

[0046] One embodiment may include, in addition to or instead of, at least one of the features 1 to 24 described above, at least one of the following: Feature 25: The reciprocating member is equipped with a plunger. Feature 26: The plunger is housed in the containment section, at least partially. Feature 27: The reciprocating member is equipped with a slider. Feature 28: The slider is mechanically connected to the plunger. Feature 29: The slider is configured to move integrally with the plunger along the guide.

[0047] An electric lubricant dispenser possessing at least features 1 to 29 can properly detect the presence of gas in the containment even if sliding resistance occurs between the slider and the guide. The plunger may have a rod-shaped (or cylindrical) form. At least a portion of the plunger, including one end (hereinafter referred to as the "insertion portion"), may be inserted into the housing portion and configured to reciprocate within the housing portion. The insertion portion may be configured to apply pressure to the lubricant as it moves in a first direction, thereby discharging the lubricant.

[0048] The plunger and slider may be in the form of separate parts, or they may be integrated into a single unit. Some or all of the aforementioned sliding resistance may include the resistance that occurs between the slider and the guide. The aforementioned lubricant may be applied to the slider and / or the guide. The aforementioned protrusions or grooves may be provided on the slider.

[0049] One embodiment may include, in addition to or instead of, at least one of the features 1 to 29 described above, at least one of the following: Feature 30: Actual operating quantity includes the amplitude of filtered physical quantities. Feature 31: Filtered physical quantities are those obtained by reducing or removing components attributable to the second load from the load physical quantities. Feature 32: Load physical quantities are physical quantities that change according to the magnitude of the motor load.

[0050] An electric lubricant dispenser having at least features 1-21, 30-32 can appropriately detect the presence of gas in the containment based on a physical quantity that reflects the motor load. The control circuit may be configured to acquire or detect a physical load quantity. The electric lubricant dispenser may include a detector configured to detect a physical load quantity and output a detection signal indicating that physical load quantity. The control circuit may acquire the physical load quantity based on the detection signal from the detector.

[0051] The amplitude of a filtered physical quantity may be defined as the difference between the maximum and minimum values ​​of the filtered physical quantity as it changes over time. This amplitude may also be the amplitude over a predetermined drive period. The predetermined drive period may be any period during the operation of the motor. For example, the predetermined drive period may be the period of one reciprocating motion of a reciprocating member.

[0052] The control circuit may be configured to perform a first calculation process to calculate a filtered physical quantity from a load physical quantity. The control circuit may perform a predetermined process based on whether the calculated filtered physical quantity satisfies predetermined requirements. An example of the first calculation process includes any process that can reduce or remove a component attributable to a second load from the load physical quantity. The first calculation process may be provided, for example, in the form of a digital low-pass filter. The cutoff frequency of the digital low-pass filter may be, for example, the reciprocal of the time required for one-way movement of a reciprocating member.

[0053] One embodiment may include, in addition to or instead of, at least one of the features 1 to 32 described above, at least one of the following: Feature 33: The control circuit is configured to calculate the moving average of the load physical quantities. Feature 34: The filtered physical quantity is the moving average mentioned above.

[0054] The moving average of the load physical quantity corresponds to the load physical quantity with the component attributable to the second load reduced or removed (i.e., the filtered physical quantity). Therefore, the actual working quantity in this case is the amplitude of the moving average.

[0055] Therefore, an electric lubricant dispenser having at least features 1-21, 30-34 can easily detect the presence of gas in the containment based on a moving average. The aforementioned first calculation process may include a process for calculating the moving average of the load physical quantities. Examples of moving averages include simple moving averages, weighted moving averages, and exponential moving averages.

[0056] The control circuit may calculate a moving average at each recurring calculation timing. The calculation timing may occur in any way. The calculation timing may occur periodically or aperiodically.

[0057] In one embodiment, the electric lubricant dispenser may be equipped with a transmission mechanism (in other words, a speed reducer) configured to (i) be connected to a motor and (ii) reduce the rotation of the motor and transmit it to a pump. In this case, the specific load may further include a third load which is a load caused by mechanical losses such as friction in the transmission mechanism.

[0058] When a specific load includes a third load, the moving average of the load's physical quantities contains many components from the first and third loads, while the component from the second load is absent or minimal. Due to the general structure of a transmission mechanism whose primary function is deceleration, the third load is constant or approximately constant, or can be considered constant, at least within the time period over which the moving average is calculated. If the third load is constant or approximately constant, the amplitude of the moving average of the load's physical quantities is close to, approximately equal to, or equal to the amplitude of the first load.

[0059] One embodiment may include, in addition to or instead of, at least one of the features 1 to 34 described above, at least one of the following: Feature 35: The moving average is the average of the load physical quantity over the calculation period. Feature 36: The calculation time is half the round-trip time required for the reciprocating member to complete one round trip.

[0060] An electric lubricant dispenser having at least features 1-21, 30-36 can easily and accurately detect the presence of gas in the containment based on a moving average. The load physical quantity may be acquired any number of times (i.e., how many times) within the calculation time, and at any timing. The load physical quantity may be acquired repeatedly, for example, periodically. The load physical quantity may be acquired at each of the above-mentioned calculation timings.

[0061] The control circuit may calculate a moving average of the load physical quantity between the first and second timings for each calculation timing. The first timing is a timing that is calculated time earlier than the second timing. The second timing may be the calculation timing, or it may be a specified time earlier than the calculation timing.

[0062] Since the second load is independent of the pressure from the lubricant, the fluctuations in the second load while the reciprocating member moves from the first end to the second end, and the fluctuations in the second load while the reciprocating member moves from the second end to the first end, are expected to be similar or nearly equal. In other words, the second load is expected to fluctuate repeatedly in a similar (or nearly equal) manner, with the one-way movement of the reciprocating member forming one period. Therefore, by calculating a moving average of half the round-trip time (i.e., the time required for one-way movement), the component attributable to the second load can be reduced or removed from the physical load quantity.

[0063] "Half of the round-trip travel time" may include a specified length of time that includes half of the round-trip travel time. The specified length of time may be, for example, less than 1 / 4 (or 1 / 8 or 1 / 16) of the round-trip travel time.

[0064] One embodiment may include, in addition to or instead of, at least one of the features 1 to 36 described above, at least one of the following: Feature 37: The control circuit sets the target rotational speed, which is the target value of the motor's rotational speed. It is composed of. Feature 38: The control circuit is configured to control the drive circuit so that the actual rotational speed of the motor matches the target rotational speed. Feature 39: The control circuit is configured to obtain the calculation time based on the set target rotational speed. Feature 40: The control circuit is configured to calculate a moving average based on the acquired calculation time.

[0065] An electric lubricant dispenser having at least features 1-21, 30-40 can easily and more accurately detect the presence of gas in the containment based on a moving average. Actual rotational speed is the actual rotational speed of the motor. Actual rotational speed may also be defined as a scalar quantity for which the direction of rotation is not taken into account.

[0066] The round-trip time may be shorter as the target rotational speed (or actual rotational speed) increases, and longer as the target rotational speed (or actual rotational speed) decreases. A first correspondence between the target rotational speed (or actual rotational speed) and the round-trip time, or a second correspondence between the target rotational speed (or actual rotational speed) and the calculation time, can be known in advance, either theoretically or experimentally. Therefore, the round-trip time can be calculated (in other words, estimated) based on the target rotational speed (or actual rotational speed) and the first correspondence described above, and the calculation time can be calculated based on that round-trip time. Alternatively, the calculation time can be calculated based on the target rotational speed (or actual rotational speed) and the second correspondence described above.

[0067] The control circuit may calculate the calculation time for each calculation timing and then calculate a moving average based on that calculated calculation time. One embodiment may include, in addition to or instead of, at least one of the above-described features 1 to 40: Feature 41: The predetermined requirement includes the condition that the maximum amplitude of the filtered physical quantity within a predetermined drive period is less than or equal to the first threshold. In other words, the predetermined requirement is satisfied in accordance with the condition that the maximum amplitude of the filtered physical quantity within a predetermined drive period is less than or equal to the first threshold.

[0068] An electric lubricant dispenser having at least features 1-21, 30-32, and 41 can appropriately and easily detect the presence of gas in the containment based on a physical quantity that reflects the motor load.

[0069] The first threshold can be determined in any way. The first threshold may be appropriately determined within a range that is smaller than the minimum amplitude of the filtered physical quantity that can occur under normal conditions (e.g., obtained theoretically or experimentally) and larger than the maximum amplitude of the filtered physical quantity that can occur under contaminated conditions.

[0070] One embodiment may include, in addition to or instead of, at least one of the above-described features 1 to 41: Feature 42: The control circuit is configured to change the first threshold value according to the operating state of the electric lubricant dispenser.

[0071] An electric lubricant dispenser having at least features 1-21, 30-32, 41, 42 is The presence of gas within the containment can be accurately detected based on a physical quantity that reflects the motor load.

[0072] The operating state can include any state that affects the physical load quantity. In other words, the operating state is such that the physical load quantity changes in response to the change in the operating state (and consequently, the filtered physical quantity changes). This can include any possible state. Examples of operating states are given below.

[0073] One embodiment may include, in addition to or instead of, at least one of the features 1 to 42 described above, at least one of the following: Feature 43: The drive circuit is configured to supply current to the motor and rotate it. Feature 44: The physical load quantity includes the magnitude of the current supplied from the drive circuit to the motor (hereinafter referred to as "motor current").

[0074] The magnitude of the motor current (e.g., the motor current value) changes depending on the motor load. Specifically, the motor current may increase as the motor load increases and decrease as the motor load decreases. The fluctuation in motor current may include a component based on fluctuations in the second load.

[0075] In contrast, the filtered physical quantity based on the motor current is one in which the component based on fluctuations in the second load has been reduced or removed, based on the magnitude of the motor current. Therefore, the control circuit can perform appropriate processing according to the gas contamination status in the containment section based on the amplitude of the filtered physical quantity.

[0076] Therefore, an electric lubricant dispenser having at least features 1-21, 30-32, 43, and 44 can appropriately detect the presence of gas in the containment based on the motor current. The electric lubricant dispenser may include a current detector configured to output a current detection signal corresponding to the magnitude of the motor current. The control circuit may acquire the current detection signal and determine the magnitude of the motor current based on the acquired current detection signal.

[0077] One embodiment may include, in addition to or instead of, at least one of the above-described features 1 to 44: Feature 45: The physical load quantity includes the actual rotational speed of the motor.

[0078] The actual rotational speed varies depending on the motor load. Specifically, the actual rotational speed may decrease as the motor load increases and increase as the motor load decreases. The fluctuation in the actual rotational speed may include a component based on fluctuations in the second load.

[0079] In contrast, the filtered physical quantity based on the actual rotational speed is the actual rotational speed with components based on fluctuations in the second load reduced or removed. Therefore, the control circuit can perform appropriate processing according to the gas contamination status in the containment section based on the amplitude of the filtered physical quantity.

[0080] Therefore, an electric lubricant dispenser having at least features 1-21, 30-32, and 45 can appropriately detect the presence of gas in the containment based on the actual rotational speed. The electric lubricant dispenser may include a rotation detector configured to output a rotation detection signal corresponding to the actual rotational speed. The control circuit may acquire the rotation detection signal and obtain the actual rotational speed based on the acquired rotation detection signal.

[0081] One embodiment may include, in addition to or instead of, at least one of the above-described features 1 to 45: Feature 46: Load physical quantities include load torque, which is the torque applied to the motor from the outside.

[0082] The load torque changes in response to the motor load. Specifically, the load torque may increase as the motor load increases and decrease as the motor load decreases. The variation in load torque may include a component based on the variation in the second load.

[0083] In contrast, the filtered physical quantity based on load torque is obtained by reducing or removing components based on fluctuations in the second load from the load torque. Therefore, the control circuit can perform appropriate processing according to the gas contamination status in the containment section based on the amplitude of the filtered physical quantity.

[0084] Therefore, an electric lubricant dispenser having at least features 1-21, 30-32, and 46 can appropriately detect the presence of gas in the containment based on the load torque. The control circuit may obtain (e.g., calculate) the load torque in any way. The control circuit may calculate (i.e., estimate) the load torque based on, for example, equation (1) below.

[0085]

number

[0086] In equation (1) above, the motor current value is the value of the current supplied from the drive circuit to the motor, the motor torque coefficient is the torque coefficient of the motor, the moment of inertia is the moment of inertia of the motor, and the motor acceleration is the acceleration of the motor (more specifically, the acceleration in the rotational direction of the motor's rotating shaft; in other words, angular acceleration). The torque coefficient is also called the torque constant.

[0087] One embodiment may include, in addition to or instead of, at least one of the features 1 to 46 described above, at least one of the following: Feature 47: The actual operating amount includes the reciprocating difference based on the load physical quantity during one reciprocating period when the reciprocating member makes one reciprocating motion. The load physical quantity is a physical quantity that changes according to the magnitude of the motor load. Feature 48: The reciprocating difference is the difference between the first level and the second level. The first level indicates the magnitude of the load physical quantity in the first period, and the second level indicates the magnitude of the load physical quantity in the second period. Feature 49: The first period is the time during which the reciprocating member moves in the first direction within one reciprocating period. The second period is the time during which the reciprocating member moves in the second direction within one reciprocating period.

[0088] The second load is generated independently of the pressure from the lubricant, as it occurs with the reciprocating movement of the reciprocating member. Therefore, the second load may occur periodically with each one-way movement of the reciprocating member (i.e., half a reciprocating movement).

[0089] Furthermore, it can be presumed that the magnitude and fluctuation patterns of the second load in the first period and the magnitude and fluctuation patterns of the second load in the second period are similar to or equal to each other without significant differences.

[0090] Therefore, by taking the difference between the first and second levels, the influence of the second load on the actual operating volume can be reduced or eliminated. If the magnitude and fluctuation pattern of the second load in the first period and the magnitude and fluctuation pattern of the second load in the second period are exactly the same, the round-trip difference will be one in which the influence of the second load has been completely eliminated. Thus, based on the round-trip difference, it is possible to appropriately determine whether or not gas is mixed into the containment.

[0091] Furthermore, even when the motor load includes the aforementioned third load, since the third load can generally be considered constant or nearly constant, the reciprocal difference will have the influence of the third load largely or completely eliminated.

[0092] Therefore, an electric lubricant dispenser having at least features 1-21, 47-49 can appropriately detect the presence of gas in the containment based on the reciprocating difference. The first level can be expressed in any way (e.g., a value, a quantity, etc.) that indicates the magnitude (or level) of the load physical quantity during the first period. The first level can be expressed in a way that allows for comparison (in other words, a significant difference) of the magnitude of the load physical quantity during the first period with at least the second level. The second level can be expressed in a way that allows for comparison (in other words, a significant difference) of the magnitude of the load physical quantity during the second period with at least the first level.

[0093] The control circuit may be configured to perform a second calculation process to calculate the round-trip difference from the physical load quantity. The second calculation process may include a process to calculate the first level, a process to calculate the second level, and a process to calculate the round-trip difference based on the calculated first and second levels. The control circuit may perform a predetermined process based on whether the calculated round-trip difference satisfies predetermined requirements.

[0094] One embodiment may include, in addition to or instead of, at least one of the above-described features 1 to 49: Feature 50: The specified requirements include the round-trip difference being less than or equal to the second threshold. In other words, the specified requirements are satisfied insofar as the round-trip difference is less than or equal to the second threshold.

[0095] An electric lubricant dispenser having at least features 1-21, 47-50 can appropriately and easily detect the presence of gas in the containment based on the reciprocating difference. The second threshold can be determined in any way. For example, the second threshold may be determined appropriately within a range that is smaller than the minimum round-trip difference that can occur under normal conditions and larger than the maximum round-trip difference that can occur under contaminated conditions.

[0096] One embodiment may include, in addition to or instead of, at least one of the above-described features 1 to 50: Feature 51: The control circuit is configured to change the second threshold value according to the operating state of the electric lubricant dispenser.

[0097] An electric lubricant dispenser possessing at least features 1-21, 47-51 can accurately detect the presence of gas in the containment based on the reciprocating difference. One embodiment may include, in addition to or instead of, at least one of the features 1 to 51 described above, at least one of the following: Feature 52: The first level is the average or maximum value of the motor current during the first period. Feature 53: The second level is the average or maximum value of the motor current during the second period.

[0098] As mentioned above, the magnitude of the motor current changes depending on the motor load. By taking the difference between the first level (corresponding to the motor current level during the first period) and the second level (corresponding to the motor current level during the second period), the current component caused by the second load can be reduced or removed from the motor current. Therefore, based on the round-trip difference, it is possible to determine whether or not gas is mixed into the housing.

[0099] Therefore, an electric lubricant dispenser having at least features 1-21, 43, 44, 47-49, 52, and 53 can appropriately detect the presence of gas in the containment based on the motor current.

[0100] One embodiment may include, in addition to or instead of, at least one of the features 1 to 53 described above, at least one of the following: Feature 54: The first level is the average or minimum value of the actual rotational speed during the first period. Feature 55: The second level is the average or minimum value of the actual rotational speed during the second period.

[0101] As mentioned above, the actual rotational speed changes depending on the motor load. By taking the difference between the first level (corresponding to the actual rotational speed level during the first period) and the second level (corresponding to the actual rotational speed level during the second period), the rotational speed component caused by the second load can be reduced or removed from the actual rotational speed. Therefore, it is possible to determine whether or not gas is mixed into the housing based on the reciprocating difference.

[0102] Therefore, an electric lubricant dispenser having at least features 1-21, 45, 47-49, 54, and 55 can appropriately detect the presence of gas in the containment based on the actual rotational speed.

[0103] One embodiment may include, in addition to or instead of, at least one of the features 1 to 55 described above, at least one of the following: Feature 56: The first level is the average or maximum value of the load torque during the first period. Feature 57: The second level is the average or maximum value of the load torque during the second period.

[0104] Load torque may be defined as the torque applied by the motor load. As mentioned above, load torque changes depending on the motor load. By taking the difference between the first level (corresponding to the load torque level in the first period) and the second level (corresponding to the load torque level in the second period), the torque component caused by the second load can be reduced or removed from the load torque. Therefore, it is possible to determine whether or not gas is mixed into the housing based on the reciprocating difference.

[0105] Therefore, an electric lubricant dispenser having at least features 1-21, 46, 47-49, 56, and 57 can appropriately detect the presence of gas in the containment based on the load torque.

[0106] One embodiment may include, in addition to or instead of, at least one of the features 1 to 57 described above, at least one of the following: Feature 58: A position detector configured to output a position signal corresponding to the position of a reciprocating member. Feature 59: The control circuit is configured to receive the position signal. Feature 60: The control circuit is configured to calculate the round-trip difference based on the first level in the first period and the second level in the second period. The first and second periods are determined based on the position signal.

[0107] An electric lubricant dispenser having at least features 1-21, 47-49, 58-60 is, The first and second periods can be easily and accurately identified, thereby enabling accurate calculation of the round-trip difference.

[0108] The position detector may be configured to output a position signal when, for example, the reciprocating member reaches a specific position along its movement path. The specific position may be, for example, the first end of the movement path or the second end of the movement path.

[0109] The control circuit may determine (or decide) the first and second periods based on the position signal. For example, the control circuit may determine the first and second periods based on the timing of receiving the position signal and the target or actual rotational speed of the motor.

[0110] If a specific position is, for example, the first end, the control circuit may estimate the time it takes to reach the second end based on the target rotational speed or actual rotational speed, in response to receiving a position signal. The period from the time the position signal is received until the estimated time has elapsed may be defined as the first period, and the period from the end of the first period until the next position signal is received may be defined as the second period.

[0111] Alternatively, the position detector may be capable of detecting when the reciprocating member reaches the first end and the second end, respectively. Specifically, the position detector may be configured to (i) output a first position signal in response to the reciprocating member reaching the first end, and (ii) output a second position signal in response to the reciprocating member reaching the second end. In this case, the control circuit may determine the period from receiving the second position signal to receiving the first position signal as the first period, and the period from receiving the first position signal to receiving the second position signal as the second period.

[0112] One embodiment may include, in addition to or instead of, at least one of the above-described features 1 to 60: Feature 61: The operating state includes the target rotational speed.

[0113] An electric lubricant dispenser having at least features 1-21, 30-32, 37, 38, 41, 42, and 61, and an electric lubricant dispenser having at least features 1-21, 47-51, and 61, can more accurately detect the presence of gas in the containment.

[0114] One embodiment may include, in addition to or instead of, at least one of the features 1 to 61 described above, at least one of the following: Feature 62: The control circuit is configured to control the drive circuit by outputting a pulse-width modulated signal with a duty cycle to the drive circuit. Feature 63: The drive circuit is configured to receive a pulse width modulated signal and drive the motor according to the received pulse width modulated signal. Feature 64: Operating conditions include duty cycle.

[0115] An electric lubricant dispenser having at least features 1-21, 30-32, 41, 42, and 62-64, and an electric lubricant dispenser having at least features 1-21, 47-51, and 62-64, can more accurately detect the presence of gas in the containment.

[0116] The drive circuit may be configured to drive the motor by supplying motor current (or power) to the motor in accordance with the duty cycle. Specifically, the drive circuit may be configured to increase the motor current as the duty cycle increases. The duty cycle may increase as the target rotational speed increases.

[0117] If the drive circuit includes the aforementioned plurality of switch elements, at least one of the plurality of switch elements may be configured to (i) receive a pulse width modulated signal and (ii) turn on or off (and thereby conduct or interrupt the corresponding current path) according to its duty cycle. That is, the larger the duty cycle, the longer the period during which it is turned on (i.e., the corresponding current path is conducted), and as a result the power supplied to the motor (and thus the motor output and / or actual rotational speed) may increase.

[0118] One embodiment may include, in addition to or instead of, at least one of the above-described features 1 to: Feature 65: The operating state includes the actual rotational speed of the motor.

[0119] An electric lubricant dispenser having at least features 1-21, 30-32, 41, 42, and 65, and an electric lubricant dispenser having at least features 1-21, 47-51, and 65, can more accurately detect the presence of gas in the containment.

[0120] The control circuit may set the threshold to be set (i.e., the first threshold or the second threshold) in any way depending on the operating state. The control circuit may set the threshold according to a pre-prepared function that takes the operating state as a variable. The control circuit may set the threshold by referring to a pre-prepared table or similar database that associates operating states with thresholds. The control circuit may increase the threshold as the target rotational speed increases. The control circuit may increase the threshold as the duty cycle increases.

[0121] One embodiment may include, in addition to or instead of, at least one of the features 1 to 65 described above, at least one of the following: Feature 66: The control circuit is configured to obtain the temperature of the electric lubricant dispenser. Feature 67: The operating state includes the aforementioned temperature.

[0122] An electric lubricant dispenser having at least features 1-21, 30-32, 41, 42, 66, and 67, and an electric lubricant dispenser having at least features 1-21, 47-51, 66, and 67, can more accurately detect the presence of gas in the containment.

[0123] The control circuit may acquire the temperature of any (where) the electric lubricant dispenser. The temperature may be the temperature of the lubricant, or a temperature that can be considered to be the temperature of the lubricant (or a change in the lubricant).

[0124] In one embodiment, the electric lubricant dispenser may include a temperature sensor configured and positioned to directly or indirectly detect the temperature of the lubricant. The control circuit may vary a threshold in response to the temperature detected by the temperature sensor. The temperature sensor may be positioned in direct contact with the lubricant, in which case it can directly detect the temperature of the lubricant. Alternatively, the temperature sensor may be positioned at a distance from the lubricant. The temperature sensor may be in any form capable of detecting temperature. Examples of temperature sensors include positive temperature coefficient (PTC) thermistors, negative temperature coefficient (NTC) thermistors, and critical temperature resistor (CTR) thermistors.

[0125] The control circuit may be configured to decrease a first or second threshold as the acquired temperature increases. The aforementioned operating conditions may include factors other than the target rotational speed, duty cycle, actual rotational speed, and temperature described above. Examples of the aforementioned operating conditions include the magnitude of the voltage applied from the drive circuit to the motor, or physical quantities that indirectly indicate the magnitude of that voltage. If the drive circuit is configured to apply the voltage of a power source (e.g., a battery) to the motor, the aforementioned operating conditions include the battery voltage. This is possible. In this case, as the battery voltage decreases, the voltage applied to the motor also decreases. Therefore, the first threshold may be set so that the first threshold decreases as the battery voltage decreases. The same applies to the second threshold. One embodiment may include a voltage detector configured to detect the battery voltage. The voltage detector may be configured to (i) receive the battery voltage and (ii) output a voltage detection signal to a control circuit corresponding to the magnitude of that voltage. The control circuit may (i) obtain the magnitude of the battery voltage based on the voltage detection signal from the voltage detector and (ii) set a first threshold (or second threshold) based on the obtained magnitude.

[0126] One embodiment may include, in addition to or instead of, at least one of the features 1 to 67 described above, at least one of the following: Feature 68: A notification unit configured to notify information indicating that gas is present in the containment compartment. Feature 69: The prescribed process includes broadcasting information via the notification unit.

[0127] In electric lubricant dispensers possessing at least features 1-21, 68, and 69, the user of the electric lubricant dispenser can easily determine if gas is present (or potentially present) in the containment.

[0128] The notification unit may notify the information in any way. The notification unit may be configured to display the information in a visible manner, for example. The notification unit may be configured to output the information by sound in a manner that is recognizable at an angle, for example.

[0129] One embodiment may include, in addition to or instead of, at least one of the features 1 to 69 described above, at least one of the following: Feature 70: The control circuit is configured to accumulate the actual number of reciprocating movements of the reciprocating member while the motor is running. The actual number of reciprocating movements is the actual number of times the reciprocating member moves back and forth. Feature 71: The control circuit is configured to stop the motor based on the actual number of round trips reaching the target number of round trips. Feature 72: The prescribed process includes temporarily suspending the accumulation of the actual number of round trips.

[0130] An electric lubricant dispenser having at least features 1-21, 70-72 can suppress or prevent the actual amount of lubricant dispensed until the motor stops from being less than the amount corresponding to the target number of reciprocating cycles.

[0131] One embodiment may include, in addition to or instead of, at least one of the above-described features 1 to 72: Feature 73: The control circuit is configured to temporarily stop accumulating the actual number of round trips, and then resume accumulating the actual number of round trips based on the fact that the actual operating amount no longer meets a predetermined requirement.

[0132] An electric lubricant dispenser possessing at least features 1-21 and 70-73 can accurately dispense an amount of lubricant corresponding to the target number of reciprocating cycles, even if gas is temporarily mixed into the storage compartment while the motor is running.

[0133] One embodiment may include, in addition to or instead of, at least one of the above-described features 1 to 73: Feature 74: The control circuit is configured to stop the motor when the actual operating amount has remained in a state that meets predetermined requirements for a predetermined period of time while the motor is running.

[0134] An electric lubricant dispenser having at least features 1 to 21, 74 allows the user to take appropriate action in response to a prolonged state of gas contamination (or potential gas contamination). In one embodiment, the motor may be stopped without waiting for a predetermined period of time to pass once certain requirements are met.

[0135] One embodiment may include, in addition to or instead of, at least one of the above-described features 1 to 74: Feature 75: The control circuit is configured to detect when certain requirements are met while the motor is running, that gas is mixed into the housing and / or that the pump is about to discharge the gas.

[0136] Electric lubricant dispensers possessing at least features 1-21 and 75 allow for various responses to gas contamination. In some embodiments, the lubricant may be in a semi-solid form. In some embodiments, the lubricant may contain grease. In some embodiments, the lubricant may be in a liquid or solid form.

[0137] One embodiment may provide a method for dispensing lubricant from an electric lubricant dispenser, comprising at least one of the following: Feature 76: The motor reciprocates the reciprocating member to discharge the lubricant from the housing. Feature 77: Perform a predetermined process based on the fact that the actual operating amount satisfies a predetermined requirement while the motor is running. The actual operating amount may have a magnitude corresponding to the magnitude of a specific load. The specific load may be a part of the motor load. The motor load may be a load applied to the motor from the outside. The predetermined requirement may indicate that gas is mixed in the housing. The specific load may include a first load. The first load may be a load applied from the reciprocating member by the reciprocating member receiving pressure from the lubricant. The specific load may not include at least a part of the second load. The second load may be a load applied from the reciprocating member by the reciprocating member itself, regardless of the pressure.

[0138] A method having at least features 76 and 77 can adequately detect the presence of gas in the containment. In one embodiment, the above features 1 to 77 may be combined in any combination.

[0139] In one embodiment, any of the above features 1 to 77 may be excluded. [2. Specific exemplary embodiments] The following exemplary embodiment provides an electric lubricant dispenser 1 shown in Figure 1. The electric lubricant dispenser 1 is configured to dispense lubricant. Specifically, the electric lubricant dispenser 1 of this embodiment is an electric grease gun configured to dispense grease.

[0140] For the sake of clarity, the directions of the electric lubricant dispenser 1 are defined as shown in Figure 1 and subsequent figures. Specifically, "up" (upward direction), "down" (downward direction), "right" (rightward direction), "left" (leftward direction), "forward" (forward direction), and "backward" (backward direction) are defined. These directions are used merely to facilitate an easy understanding of the structure of the electric lubricant dispenser 1 and are not intended to limit the orientation of the electric lubricant dispenser 1. The electric lubricant dispenser 1 can be oriented in any direction.

[0141] [2-1. First Embodiment] (2-1-1) Mechanical configuration of electric lubricant dispenser As shown in Figures 1 and 2, the electric lubricant dispenser 1 of this first embodiment includes a housing 2. The housing 2 comprises a first split housing 2a and a second split housing 2b that are joined together.

[0142] The housing 2 has a motor housing 4 in its center in the height direction. The height direction corresponds to the direction from the bottom to the top or from the top to the bottom of the housing 2. In this first embodiment, the motor housing 4 is cylindrical and extends in the length direction. The length direction corresponds to the direction from the front to the rear or from the rear to the front of the housing 2. The motor housing 4 houses a motor 20. The motor 20 is an electric motor.

[0143] The housing 2 is equipped with a grip 5 on its upper part. In this first embodiment, the grip 5 extends in the longitudinal direction and is bent downward. The motor housing 4 is provided with a front coupling portion 6 at its front end. The front coupling portion 6 is coupled to the front end of the grip 5. The motor housing 4 is provided with a rear coupling portion 7 at its rear end. The rear coupling portion 7 is coupled to the rear end of the grip 5. In this first embodiment, the rear coupling portion 7 rises upward so as to form a space between the motor housing 4 and the grip 5.

[0144] The electric lubricant dispenser 1 is equipped with a trigger switch 8 housed within the grip 5. The electric lubricant dispenser 1 is also equipped with a trigger 9 for the user of the electric lubricant dispenser 1 to manually operate the trigger switch 8.

[0145] Trigger 9 is pulled by the user to drive the motor 20 (i.e., to dispense grease). Trigger 9 is configured to be displaceable between an initial position and a maximum position. When trigger 9 is not manually operated, it is in the initial position. In response to manual operation, trigger 9 moves from the initial position towards the maximum position.

[0146] When the trigger 9 is located between the initial position and the minimum position, the trigger switch 8 is off and the motor 20 is stopped. The minimum position is located between the initial position and the maximum position. When the trigger 9 is located between the minimum position and the maximum position, the trigger switch 8 is on and the motor 20 is rotatable. In this first embodiment, the trigger 9 protrudes downward from the grip 5.

[0147] The grip 5 is equipped with a light 10 on its front surface. In this first embodiment, the light 10 is equipped with a light-emitting diode (LED), which is not shown, as a light source. The grip 5 is equipped with an operation panel 70 on its front upper surface. The operation panel 70 is configured to be manually operated by the user to turn the light 10 on or off, or to change the settings of the electric lubricant dispenser 1.

[0148] The grip 5 is equipped with a first lock button 12 in front of the trigger 9. The first lock button 12 is configured to be pressed by the user to lock the trigger 9 in its maximum position. The grip 5 is equipped with a second lock button 13 below the first lock button 12. The second lock button 13 is configured to be pressed by the user to lock the trigger 9 in its initial position (i.e., unpulled position).

[0149] The rear coupling portion 7 is provided with a battery holding portion 14 at its rear end. The battery holding portion 14 is configured so that the battery pack 15 can be detachably attached to it. In this first embodiment, the battery holding portion 14 is configured such that the battery pack 15 is attached to the battery holding portion 14 by sliding the battery pack 15 from above to below at its rear end.

[0150] The battery pack 15 includes a battery (not shown) inside. In this first embodiment, the battery has a rated voltage of 36 volts. The battery pack 15 supplies power from the battery to the electric lubricant dispenser 1 via the battery holder 14.

[0151] The battery holder 14 includes a terminal block 16 inside. The terminal block 16 is configured to be electrically connected to the battery pack 15 mounted in the battery holder 14. In this first embodiment, the terminal block 16 extends in the height direction.

[0152] The battery holder 14 houses the control unit 17 in front of the terminal block 16. In this first embodiment, the control unit 17 extends in the height direction. The control unit 17 includes a control circuit board 18.

[0153] In this first embodiment, the motor 20 is an inner rotor type brushless motor (more specifically, a three-phase brushless DC motor). In another embodiment, the motor 20 may be any other type of motor (for example, a brushed DC motor).

[0154] The motor 20 includes a stator 21. The stator 21 has three lead wires 27 (Figure 2 shows only one lead wire 27). The stator 21 has a first insulator 23A at its front end. The stator 21 has a second insulator 23B at its rear end.

[0155] The stator 21 comprises three coils 24 wound around a first insulator 23A and a second insulator 23B. The second insulator 23B has six terminals (not shown) fused to the ends of the wires of these coils 24.

[0156] The second insulator 23B includes a short-circuit member 25. The short-circuit member 25 comprises three insert-molded short-circuit fittings 26 (Figure 2 shows only two short-circuit fittings 26). These short-circuit fittings 26 electrically connect the terminals of the second insulator 23B so that the coil 24 described above forms a delta configuration (or delta connection). The coil 24 described above may also form a star configuration (or star connection).

[0157] The stator 21 includes a sensor circuit board 28 between the second insulator 23B and the short-circuit member 25. The sensor circuit board 28 includes first to third rotational position sensors 28A to 28C (see Figure 6). In this first embodiment, the first to third rotational position sensors 28A to 28C are Hall sensors, but are not limited to Hall sensors. The first to third rotational position sensors 28A to 28C are connected to three signal lines 29 (Figure 2 shows only one signal line 29). The lead wires 27 and signal lines 29 are connected to the control circuit board 18 of the control unit 17.

[0158] The motor 20 has a rotor 22 inside a stator 21. The rotor 22 has a rotating shaft 30 at its center. The rotating shaft 30 has two or more permanent magnets 31 embedded in its outer circumferential wall.

[0159] The first to third rotational position sensors 28A to 28C (i) are arranged around the rotor 22 and (ii) each output first to third rotational signals corresponding to the rotational position of the rotational axis 30 (and consequently the rotational position of the rotor 22).

[0160] The rotating shaft 30 is equipped with a fan 32 attached to its front end. In this first embodiment, the fan 32 extends perpendicular to the rotating shaft 30. The rear coupling portion 7 houses the first bearing 35 behind the short-circuiting member 25. The first bearing 35 rotatably supports the rear end of the rotating shaft 30.

[0161] The motor housing 4 includes a gear housing 40 in front of the motor 20. In this first embodiment, the gear housing 40 is cylindrical. The gear housing 40 has an opening at its rear end. The gear housing 40 includes a bracket plate 41 attached to this opening. The rotating shaft 30 protrudes into the gear housing 40 through the bracket plate 41. The bracket plate 41 holds a second bearing 42. The second bearing 42 rotatably supports the front end of the rotating shaft 30.

[0162] The gear housing 40 is equipped with a spindle 44 at its front end. The gear housing 40 houses a transmission mechanism 43. The transmission mechanism 43 is connected to the rotating shaft 30 and transmits the rotation of the rotating shaft 30 to the pump 60 described later via the spindle 44. The transmission mechanism 43 is configured to (i) receive the rotation of the rotating shaft 30 and (ii) rotate the spindle 44 at a rotational speed lower than the rotational speed of the rotating shaft 30. In other words, the transmission mechanism 43 reduces the rotational speed of the rotating shaft 30 and transmits it to the spindle 44. The transmission mechanism 43 may be equipped with planetary gears.

[0163] Housing 2 includes a crank housing 45 at the front end of the gear housing 40. In this first embodiment, the crank housing 45 extends in the height direction. The spindle 44 protrudes from the gear housing 40 into the crank housing 45.

[0164] The crank housing 45 houses a crank disc 46 located at the front end of the spindle 44. The crank disc 46 is equipped with an eccentric pin 47 that protrudes forward. The crank housing 45 is equipped with a slider 48 in front of the crank disc 46. The slider 48 has an elongated hole 48A that extends in the width direction. The width direction corresponds to the direction from right to left or left to right of the housing 2. An eccentric pin 47 is inserted into the elongated hole 48A. The slider 48 is connected to a plunger 50 at the center of its lower end. The plunger 50 has an upper end connected to the slider 48 and extends downward.

[0165] The crank housing 45 includes a slider guide 49 that supports the slider 48 so that it can move up and down. The slider 48 and slider guide 49 are also shown in Figure 3. The slider 48 is movable in the height direction along the slider guide 49.

[0166] In this first embodiment, the slider 48 and the slider guide 49 are coated with a lubricant to reduce friction between them. Note that the lubricant referred to here is different from grease. The slider guide 49 is an example of a guide in the overall embodiment.

[0167] In the crank housing 45 configured in this way, when the crank disc 46 rotates together with the spindle 44, the eccentric pin 47 undergoes eccentric motion. The vertical stroke of the eccentric pin 47 causes the slider 48 to reciprocate integrally with the plunger 50 in a first and second direction. In other words, the crank disc 46 and slider 48 convert the rotational motion of the motor 20 into linear reciprocating motion. The first direction corresponds to the downward direction, and the second direction corresponds to the upward direction. Hereinafter, the lowest position in the reciprocating range of the slider 48 and plunger 50 (i.e., the end in the first direction) will be referred to as the lowest end, and the highest position in the reciprocating range (i.e., the end in the second direction) will be referred to as the uppermost end.

[0168] The electric lubricant dispenser 1 is equipped with a position detector 95 (see Figure 5) in front of the slider guide 49. The position detector 95 is configured to output first and second slider position signals corresponding to the position of the slider 48.

[0169] The position detector 95 includes a first detector 96A, a second detector 96B, and a magnet 97, as shown in Figure 2. The magnet 97 is also shown in Figure 3. The magnet 97 is arranged to move integrally with the slider 48. Specifically, in this first embodiment, the magnet 97 is attached to the front end surface of the slider 48. The first and second detectors 96A and 96B are spaced a certain distance forward of the magnet 97 in the front-rear direction. In this first embodiment, each of the first and second detectors 96A and 96B is equipped with a Hall sensor.

[0170] The first detector 96A faces the magnet 97 in the front-to-back direction when the slider 48 is at its lowest position. The first detector 96A outputs a first slider position signal when the slider 48 is at its lowest position. The second detector 96B faces the magnet 97 in the front-to-back direction when the slider 48 is at its highest position. The second detector 96B outputs a second slider position signal when the slider 48 is at its highest position.

[0171] The crank housing 45 is equipped with a front holder 51 at its lower part. The housing 2 is equipped with a rear holder 52 behind the front holder 51 and below the motor housing 4. The rear holder 52 is equipped with two legs 53 that protrude downward at its front and rear ends.

[0172] The electric lubricant dispenser 1 comprises a tank 54 supported by a front holder 51 and a rear holder 52. The tank 54 has an open front end. The tank 54 reaches the rear surface of the front holder 51 through the rear holder 52. The front end of the tank 54 is screwed into the rear surface of the front holder 51. In other words, the tank 54 extends longitudinally below the motor housing 4.

[0173] The tank 54 houses a rod 55. The rod 55 extends from the rear end of the tank 54 to the front end of the tank 54. The rod 55 holds the piston 56 so that it can move along the rod 55. The rod 55 has a rear end that protrudes from the tank 54. The tank 54 has a handle 57 attached to the rear end of the rod 55. The tank 54 houses a coil spring 58. The coil spring 58 is located behind the piston 56 and biases the piston 56 forward. The tank 54 houses a grease-filled cartridge (not shown) in front of the piston 56. This cartridge is pressed against the piston 56, supplying grease into the front holder 51.

[0174] The front holder 51 is equipped with a pump 60. The pump 60 is equipped with the plunger 50 described above. The pump 60 is equipped with an upper cylindrical portion 60A and a lower cylindrical portion 60B. The upper cylindrical portion 60A and the lower cylindrical portion 60B form a chamber 63. The plunger 50 is located inside the chamber 63. The chamber 63 is an example of a housing in the overall embodiment.

[0175] Chamber 63 has an inlet hole 63A between the upper cylindrical portion 60A and the lower cylindrical portion 60B. Chamber 63 communicates with tank 54 through the inlet hole 63A. Grease is supplied from the cartridge into chamber 63 through the inlet hole 63A.

[0176] The upper cylinder portion 60A is equipped with a seal ring 61A at its top. The plunger 50 passes through the seal ring 61A. The seal ring 61A prevents or suppresses grease in the chamber 63 from leaking out of the upper cylinder portion 60A upward.

[0177] The lower cylinder portion 60B is provided with a discharge passage 66. The discharge passage 66 (i) communicates with the chamber 63 via a check valve 64, which will be described later, and (ii) extends in the longitudinal direction. The front holder 51 is provided with a front cylinder portion 60C at its front end. The front cylinder portion 60C protrudes forward from the front holder 51. The discharge passage 66 passes through the center of the front cylinder portion 60C. The discharge passage 66 discharges at its front end. It is equipped with an outlet 66A. The front cylinder section 60C is connected to a hose 68. Grease is discharged from the outlet 66A through the hose 68 to the outside of the electric lubricant dispenser 1.

[0178] The pump 60 is equipped with the aforementioned check valve 64 at the bottom of the chamber 63. The check valve 64 allows grease to flow out of the chamber 63 into the discharge passage 66, while suppressing or preventing backflow of grease from the discharge passage 66 into the chamber 63.

[0179] The front cylinder portion 60C is equipped with a relief valve 69 on its right side. The relief valve 69 is configured to release the grease in the discharge passage 66 to the outside of the electric lubricant supply unit 1 when the pressure of the grease in the discharge passage 66 exceeds a predetermined pressure.

[0180] The front holder 51 is equipped with an air drain valve 67 at its front end. The air drain valve 67 is provided to release gas (e.g., air) inside the chamber 63 (more specifically near the inlet hole 63A) to the outside of the electric lubricant dispenser 1. When the air drain valve 67 is tightened, the chamber 63 is isolated from the outside of the electric lubricant dispenser 1. The electric lubricant dispenser 1 is normally used with the air drain valve 67 tightened. When the air drain valve 67 is loosened, the chamber 63 communicates with the outside of the electric lubricant dispenser 1. If gas is present in the chamber 63 at this time, that gas can be released to the outside of the electric lubricant dispenser 1 via the air drain valve 67.

[0181] (2-1-2) Mechanical operation of the electric lubricant dispenser In the electric lubricant dispenser 1 configured as described above, when the user pulls the trigger 9, the motor 20 rotates, and consequently, the rotating shaft 30 rotates.

[0182] The rotation of the rotating shaft 30 is transmitted to the spindle 44 via the transmission mechanism 43, and the crankcase 46 rotates together with the spindle 44. This causes the eccentric pin 47 to perform eccentric motion. In response to the eccentric motion of the eccentric pin 47, (i) the slider 48 moves up and down along the slider guide 49 within a reciprocating range (in other words, a movement path), and (ii) the plunger 50 reciprocates up and down (i.e., in the first and second directions) integrally with the slider 48. The slider 48 and the plunger 50 are examples of reciprocating members in the overall embodiment.

[0183] More specifically, as shown in Figure 3, the plunger 50 moves up and down through the first to fourth states in this order. Figure 3 schematically shows the position of the inlet hole 63A. The first state is the state in which the slider 48 is in the process of moving in the second direction. More specifically, the first state is the state in which the slider 48 is in an intermediate position within its reciprocating range. Figure 2 shows the electric lubricant dispenser 1 in the first state. In the first state, as is clear from Figures 2 and 3, the plunger 50 is inserted into the lower cylinder portion 60B. When the motor 20 rotates further from the first state, the slider 48 and plunger 50 move in the second direction, and the system transitions to the second state.

[0184] The second state is when the slider 48 has reached its uppermost position. Before the slider 48 reaches its uppermost position, the lower end of the plunger 50 disengages from the lower cylinder 60B, allowing grease to flow from the tank 54 into the chamber 63. In the second state, the lower end of the plunger 50 is either fully retracted into the upper cylinder 60A or slightly protruding downward from the upper cylinder 60A. In the second state, the second slider position signal is output from the second detector 96B. If the motor 20 rotates further from the second state, the slider 48 moves in the first direction and transitions to the third state.

[0185] The third state is when the slider 48 is in the process of moving in the first direction. More specifically, the third state is when the slider 48 is in an intermediate position within its reciprocating range. In the third state, the plunger 50 is inserted into the lower cylinder portion 60B, similar to the first state. When the motor 20 rotates further from the third state, it transitions to the fourth state.

[0186] The fourth state is when the slider 48 has reached its lowest point. In the fourth state, the lower end of the plunger 50 has reached near the lower end of the chamber 63. In the fourth state, the first slider position signal is output from the first detector 96A. If the motor 20 rotates further from the fourth state, the slider 48 moves in the second direction and transitions to the first state.

[0187] Between the second and fourth states, the plunger 50 moves in the first direction. During this time, the grease in the chamber 63 is pressed against the bottom surface of the plunger 50 (i.e., the lower end surface; hereinafter referred to as the "plunger lower end surface"). As a result, the grease flows into the hose 68 via the check valve 64, the discharge passage 66, and the discharge port 66A, and is discharged from the hose 68 to the outside of the electric lubricant supply unit 1.

[0188] Thus, while the motor 20 is rotating, the slider 48 (and consequently the plunger 50) moves back and forth repeatedly, causing grease to be continuously discharged (or may be discharged) from the discharge port 66A. Grease is discharged each time the plunger 50 makes one back-and-forth motion. Therefore, one back-and-forth motion of the plunger 50 can be rephrased as one grease discharge operation.

[0189] Note that the motor 20 may rotate in the opposite direction to the operation example in Figure 3. In this case, the plunger 50 moves up and down through the fourth to first states in that order, thereby discharging grease in the same way as the operation example in Figure 3.

[0190] (2-1-3) Details of the control panel As shown in Figure 4, the control panel 70 includes a first switch 71. In this first embodiment, the first switch 71 and the second and third switches 72 and 73, which will be described later, are push-button switches. In another embodiment, the first to third switches 71 to 73 may be other types of manual switches.

[0191] Each time the first switch 71 is briefly pressed, the rotational speed level of the motor 20 is sequentially switched to one of several rotational speed levels (for example, four levels: levels 1 to 4). For each rotational speed level, the maximum rotational speed of the motor 20 is set. The maximum rotational speed increases in the order of, for example, level 1, level 2, level 3, and level 4.

[0192] The motor 20 is rotated up to the maximum rotational speed corresponding to the set rotational speed level. Specifically, for example, the target rotational speed is set up to the maximum rotational speed, depending on the operating mode and / or the amount (i.e., position) of the trigger 9, as described later. The motor 20 is controlled to maintain a constant rotational speed (in other words, speed feedback control) so that its rotational speed (more specifically, the actual rotational speed; hereinafter referred to as "actual rotational speed") matches the target rotational speed.

[0193] When the first switch 71 is pressed and held, the light 10 turns on. After the light 10 turns on, the light 10 may turn off, for example, if (i) a predetermined time has elapsed or (ii) the first switch 71 is pressed and held again. A short press corresponds to an operation in which the switch is released before a certain period of time has elapsed since it was pressed. A long press corresponds to an operation in which the switch is pressed and held continuously for a certain period of time or longer before being released.

[0194] The control panel 70 is equipped with a first display screen 74. The first display screen 74 displays information indicating the set rotation speed level (for example, a number from "1" to "4"). "1" to "4" indicate the first to fourth levels, respectively. In this first embodiment, the first display screen 74 and the second and third display screens 75A and 75B, described later, are each 7-segment displays. In another embodiment, each of the first to third display screens 74, 75A, and 75B may be other types of display screens, including liquid crystal displays (LCDs).

[0195] The control panel 70 includes the aforementioned second switch 72 and third switch 73. Each time the second and third switches 72 and 73 are pressed simultaneously, the operating mode of the electric lubricant dispenser 1 is switched. In this first embodiment, the operating modes include a continuous discharge mode and an automatic discharge mode (or a quantitative discharge mode). In this first embodiment, each time the second and third switches 72 and 73 are pressed simultaneously, the operating mode alternately switches between the continuous discharge mode and the automatic discharge mode.

[0196] In continuous discharge mode, the motor 20 rotates continuously while the trigger 9 is pulled. In this first embodiment, the target rotational speed in continuous discharge mode changes depending on the position of the trigger 9. Specifically, the target rotational speed increases continuously or in steps as the trigger 9 moves from the minimum position to the target arrival position. More specifically, the target rotational speed increases from a predetermined minimum value (e.g., zero) towards a maximum rotational speed corresponding to a set rotational speed level. The target arrival position may be located between the minimum and maximum positions, or it may coincide with the maximum position. When the trigger 9 reaches the target arrival position, the target rotational speed reaches the maximum rotational speed corresponding to the set rotational speed level. If the trigger 9 is located between the target arrival position and the maximum position, the target rotational speed is maintained at the maximum rotational speed.

[0197] In addition, the target rotational speed in continuous discharge mode may be maintained at a constant rotational speed (for example, the maximum rotational speed corresponding to the set rotational speed level) regardless of the position of the trigger 9.

[0198] In automatic dispensing mode, the motor 20 starts rotating when the trigger 9 is pulled. After rotation begins, when the plunger 50 (in other words, the slider 48) has reciprocated a target number of times (in other words, when the predetermined dispensing operation has been performed a target number of times, or to put it another way, when an amount of grease corresponding to the target number of reciprocations has been dispensed), the motor 20 automatically stops, even if the trigger 9 is still pulled. The target number of reciprocations can be set to any value by the user.

[0199] In automatic dispensing mode, the target rotational speed is set to a constant rotational speed (for example, the maximum rotational speed corresponding to the set rotational speed mode) regardless of the position of trigger 9. However, the target rotational speed in automatic dispensing mode may change depending on the position of trigger 9, similar to continuous dispensing mode.

[0200] The control panel 70 is equipped with a setting count display screen 75. The setting count display screen 75 (i) comprises the aforementioned second display screen 75A and third display screen 75B, and (ii) is capable of displaying a two-digit number. When the operating mode is set to automatic discharge mode, the target number of round trips is displayed on the setting count display screen 75.

[0201] In this first embodiment, in automatic dispensing mode, any target number of round trips can be set, up to a predetermined maximum set number of 99 or less. The user can set the target number of round trips to any value by operating the second switch 72 or the third switch 73. Specifically, in automatic dispensing mode, each time the second switch 72 is pressed, the target number of round trips increases by one, and the increased target number of round trips is set as the new target number of round trips and displayed on the set number display screen 75. Conversely, in automatic dispensing mode, each time the third switch 73 is pressed, the target number of round trips decreases by one, and the decreased target number of round trips is The new target number of round trips is set and displayed on the setting count display screen 75. The maximum number of round trips can be determined in any way and may be set to 100 or more.

[0202] (2-1-4) Electrical configuration of the electric lubricant dispenser Referring to Figure 5, the electrical configuration of the electric lubricant dispenser 1 will be described. The electric lubricant dispenser 1 includes a control circuit board 18 with a ground. The electric lubricant dispenser 1 includes a power line Lp extending from the positive terminal of the battery pack 15 mounted in the battery holder 14 to the control circuit board 18. The electric lubricant dispenser 1 includes a ground line Ln extending from the negative terminal of the battery pack 15 mounted in the battery holder 14 to the ground on the control circuit board 18. The battery pack 15 applies its rated voltage between the power line Lp and the ground line Ln.

[0203] The electric lubricant dispenser 1 includes a power supply circuit 84. In this first embodiment, the power supply circuit 84 is located on the control circuit board 18. The power supply circuit 84 is connected to the power line Lp and to ground. The power supply circuit 84 generates a fixed DC voltage (hereinafter referred to as "power supply voltage") Vc based on the battery voltage supplied from the battery pack 15.

[0204] The electric lubricant dispenser 1 is equipped with a control circuit 80. The control circuit 80 is located on a control circuit board 18 and operates in response to a power supply voltage Vc. The control circuit 80 is a microcomputer comprising a CPU 80A and a semiconductor memory 80B. The semiconductor memory 80B includes ROM, RAM, and rewritable non-volatile memory. Non-volatile memory includes, for example, EEPROM, flash memory, ReRAM, FeRAM, etc. The various functions of the control circuit 80 are realized by the CPU 80A executing a program stored in the semiconductor memory 80B. When the CPU 80A executes this program, the method corresponding to this program is executed.

[0205] In another embodiment, the control circuit 80 may include an additional microcomputer. In yet another embodiment, some or all of the functions achieved by the CPU 80A may be achieved by one or more electronic components (e.g., integrated circuits). In yet another embodiment, the control circuit 80 may be a logic circuit (or wired logic connection) including two or more electronic components. In yet another embodiment, the control circuit 80 may include an ASIC and / or ASSP. In yet another embodiment, the control circuit 80 may include a programmable logic device on which a reconfigurable logic circuit can be constructed. An example of a programmable logic device is an FPGA.

[0206] The electric lubricant dispenser 1 includes a drive circuit 82 configured to drive the motor 20 by supplying current (hereinafter referred to as "motor current") to the motor 20. The drive circuit 82 is electrically connected to the power line Lp and the ground line Ln. The drive circuit 82 (i) receives the battery voltage and (ii) generates a three-phase voltage (i.e., generates three-phase power) from the battery voltage and supplies it to the motor 20. In this first embodiment, the drive circuit 82 is located on the control circuit board 18.

[0207] The drive circuit 82 is a three-phase full-bridge circuit, but is not limited to a three-phase full-bridge circuit. The drive circuit 82 includes first to third switches Q1 to Q3 located on the high side and fourth to sixth switches Q4 to Q6 located on the low side. The first to third switches Q1 to Q3 are connected to the power line Lp and the corresponding lead wires 27 of the motor 20, respectively, and function as so-called high-side switches. The fourth to sixth switches Q4 to Q6 are connected to the corresponding lead wires 27 and ground, respectively, and function as so-called low-side switches.

[0208] The first to sixth switches Q1 to Q6 each receive the first to sixth drive control signals from the control circuit 80 and turn on or off according to the respective drive control signals they receive. In this first embodiment, the first to sixth drive control signals may be pulse width modulated signals. The first to sixth switches Q1 to Q6 are semiconductor switches. Examples of semiconductor switches include field-effect transistors (FETs), bipolar transistors, and insulated-gate bipolar transistors (IGBTs).

[0209] When the motor 20 is driven, basically one of the high-side switches and one of the low-side switches are turned on. As a result, motor current flows from the positive terminal of the battery through the high-side switch, the motor 20, and the low-side switch to the negative terminal of the battery, causing the motor 20 to rotate.

[0210] The electric lubricant dispenser 1 is equipped with a current detector 93. The current detector 93 is located on the current path connecting the drive circuit 82 to the negative terminal of the battery. The current detector 93 outputs a current detection signal to the control circuit 80 that corresponds to the magnitude of the motor current flowing through this current path.

[0211] The electric lubricant dispenser 1 includes a sliding resistor 81 having a lever 81A. The lever 81A has a displaceable first end and a second end connected to the control circuit 80. The sliding resistor 81 has a resistance value that changes depending on the position of the first end of the lever 81A. The second end of the lever 81A outputs a voltage (hereinafter referred to as "trigger voltage") of a magnitude corresponding to the resistance value to the control circuit 80. The first end of the lever 81A is displaced according to the position of the trigger 9 in the range from the initial position to the maximum position. For example, the resistance value of the sliding resistor 81 is minimum when the trigger 9 is in the initial position and increases as the trigger 9 approaches the maximum position from the initial position.

[0212] The electric lubricant dispenser 1 is equipped with first to fourth pull-up resistors R1 to R4. In this first embodiment, the first to fourth pull-up resistors R1 to R4 are located on the control circuit board 18. Each of the first to fourth pull-up resistors R1 to R4 has a first terminal connected to the power supply circuit 84 to receive the power supply voltage Vc from the power supply circuit 84. The first pull-up resistor R1 has a first terminal connected to the trigger switch 8 and a second terminal connected to the control circuit 80. The second pull-up resistor R2 has a first terminal connected to the first switch 71 and a second terminal connected to the control circuit 80. The third pull-up resistor R3 has a first terminal connected to the second switch 72 and a second terminal connected to the control circuit 80. The fourth pull-up resistor R4 has a first terminal connected to the third switch 73 and a second terminal connected to the control circuit 80. Each of the trigger switch 8, the first switch 71, the second switch 72, and the third switch 73 has a second terminal connected to ground on the control circuit board 18.

[0213] When the trigger switch 8, the first switch 71, the second switch 72, and the third switch 73 are off, the second terminals of the first to fourth pull-up resistors R1 to R4 have a voltage at the same level as the power supply voltage Vc (i.e., a high level). When the trigger switch 8, the first switch 71, the second switch 72, and the third switch 73 are on, the second terminals of the first to fourth pull-up resistors R1 to R4 have a voltage at the same level as ground (i.e., a low level). The first to fourth pull-up resistors R1 to R4 may have the same resistance value or may have different resistance values.

[0214] The control circuit 80 can detect whether the trigger 9, the first switch 71, the second switch 72, and the third switch 73 are manually operated based on the voltages at the second terminals of the first to fourth pull-up resistors R1 to R4. Specifically, if the voltages at the second terminals of the first to fourth pull-up resistors R1 to R4 are high, the control circuit 80 detects that the trigger 9, the first switch 71, the second switch 72, and the third switch 73 are not manually operated. If the voltage across the second terminals of the four pull-up resistors R1 to R4 is low, the control circuit 80 detects that the trigger 9, the first switch 71, the second switch 72, and the third switch 73 are being operated manually.

[0215] The control circuit board 18 is connected to the first to third display screens 74, 75A, and 75B of the operation panel 70. The first to third display screens 74, 75A, and 75B operate by receiving a power supply voltage Vc from the control circuit board 18. In addition, the first to third display screens 74, 75A, and 75B each receive the first to third display control signals from the control circuit 80 and display information.

[0216] The control circuit board 18 is connected to the sensor circuit board 28. The first to third rotational position sensors 28A to 28C on the sensor circuit board 28 operate by receiving a power supply voltage Vc from the control circuit board 18. The first to third rotational position sensors 28A to 28C are connected to the control circuit 80 via a signal line 29 and output the first to third rotational signals to the control circuit 80. The first to third rotational signals are associated with each of the three phases of the motor 20 (i.e., U phase, V phase, and W phase). The first to third rotational signals are, for example, sinusoidal signals. The voltage of each of the first to third rotational signals reverses from positive to negative or negative to positive each time the rotor 22 rotates 180 degrees in electrical angle. The first to third rotational signals have a phase difference of 120 degrees in electrical angle from each other.

[0217] In another embodiment, the sensor circuit board 28 may be configured to output a single rotation detection signal (e.g., a pulse signal) to the control circuit 80 instead of the first to third rotation signals. The rotation detection signal changes each time the rotor 22 rotates by 60 degrees in electrical angle.

[0218] The electric lubricant dispenser 1 includes a temperature sensor 100 connected to a control circuit 80. The temperature sensor 100 is provided to detect the temperature of the electric lubricant dispenser 1. More specifically, the temperature sensor 100 is provided to directly or indirectly detect the temperature of the grease. The temperature sensor 100 outputs a temperature detection signal indicating the detected temperature to the control circuit 80. The temperature sensor 100 may be in any form capable of detecting temperature. The temperature sensor 100 may include, for example, a positive temperature coefficient (PTC) thermistor, a negative temperature coefficient (NTC) thermistor, or a critical temperature resistor (CTR) thermistor.

[0219] The temperature sensor 100 may be positioned in any location that allows it to directly or indirectly detect the temperature (or level) of the grease. For example, the temperature sensor 100 may be positioned in a location that allows it to directly contact the grease. More specifically, the temperature sensor 100 may be positioned, for example, at the inlet of the pump 60 (e.g., the inlet hole 63A).

[0220] Alternatively, the temperature sensor 100 may be positioned in a location that does not come into contact with the grease. Specifically, the temperature sensor 100 may be positioned, for example, on the surface or inside the grip 5, around the front holder 51, or near the tank 54 in the housing 2.

[0221] The control circuit board 18 is connected to the position detector 95. The first and second detectors 96A and 96B in the position detector 95 operate by receiving a power supply voltage Vc from the control circuit board 18. The first and second detectors 96A and 96B output the first and second slider position signals to the control circuit 80.

[0222] The position detector 95 is basically used in the fourth to sixth embodiments described later, but not in this first embodiment or the second and third embodiments described later. Therefore, the position detector 95 may be omitted in the first to third embodiments. However, even in the first to third embodiments, various processes may be performed based on the first and second slider position signals from the position detector 95.

[0223] (2-1-5) Functional configuration of an electric lubricant dispenser Referring to Figure 6, the functions of the control circuit 80 will be explained. The control circuit 80 includes the functions of a pull amount detection unit 77, a switch detection unit 78, a round trip count setting unit 83, a round trip count calculation unit 79, a display control unit 85, a speed setting unit 86, an operation mode setting unit 87, a timing unit 88, a plunger-related detection unit 89, an air entrapment detection unit 90, an operation control unit 91, and a motor drive control unit 92. In this first embodiment, these functions are incorporated into the control circuit 80 by software. In other words, these functions are realized by the CPU 80A executing the corresponding program (specifically, the main processing described later).

[0224] In another embodiment, at least one of the functions of the pull amount detection unit 77, switch detection unit 78, reciprocation count setting unit 83, reciprocation count calculation unit 79, display control unit 85, speed setting unit 86, operation mode setting unit 87, timing unit 88, plunger-related detection unit 89, air lock detection unit 90, operation control unit 91, and motor drive control unit 92 may be incorporated into the control circuit 80 by hardware (electronic circuit) rather than software. In yet another embodiment, at least one of the functions of the pull amount detection unit 77, switch detection unit 78, reciprocation count setting unit 83, reciprocation count calculation unit 79, display control unit 85, speed setting unit 86, operation mode setting unit 87, timing unit 88, plunger-related detection unit 89, air lock detection unit 90, operation control unit 91, and motor drive control unit 92 may be omitted.

[0225] The pull amount detection unit 77 receives a trigger voltage from the sliding resistor 81. Based on the trigger voltage, the pull amount detection unit 77 detects the actual pull amount of the trigger 9. The actual pull amount is the actual pull amount (i.e., the actual position). If the magnitude of the trigger voltage corresponds to the initial position of the trigger 9, the pull amount detection unit 77 detects an actual pull amount of zero. If the magnitude of the trigger voltage corresponds to the maximum position of the trigger 9, the pull amount detection unit 77 detects an actual pull amount of the maximum value. If the magnitude of the trigger voltage corresponds to an intermediate position of the trigger 9, the pull amount detection unit 77 detects an actual pull amount between zero and the maximum value. The intermediate position is between the initial position and the maximum position. The pull amount detection unit 77 outputs the detected actual pull amount to the speed setting unit 86.

[0226] The switch detection unit 78 detects the change from off to on and from on to off for each of the trigger switch 8, the first switch 71, the second switch 72, and the third switch 73. When the trigger switch 8 changes from off to on, the switch detection unit 78 outputs a first signal to the operation control unit 91 and the round-trip count calculation unit 79. The first signal indicates that the trigger switch 8 has changed from off to on. When the trigger switch 8 changes from on to off, the switch detection unit 78 outputs a second signal to the operation control unit 91 and the round-trip count calculation unit 79. The second signal indicates that the trigger switch 8 has changed from on to off. When the first switch 71 changes from off to on, the switch detection unit 78 outputs a third signal to the operation mode setting unit 87. The third signal indicates that the first switch 71 has changed from off to on. When the second switch 72 and the third switch 73 are simultaneously turned on, the switch detection unit 78 outputs a fourth signal to the operation mode setting unit 87. Simultaneous on means that the switches change from off to on at the same time or approximately at the same time. The fourth signal indicates that the second switch 72 and the third switch 73 have been turned on simultaneously.

[0227] While the third switch 73 is off, the switch detection unit 78 outputs a fifth signal to the reciprocation number setting unit 83 in response to the second switch 72 changing from off to on. The fifth signal indicates that the second switch 72 has changed from off to on. While the second switch 72 is off, the switch detection unit 78 outputs a sixth signal to the reciprocation number setting unit 83 in response to the third switch 73 changing from off to on. The sixth signal indicates that the third switch 73 has changed from off to on.

[0228] The operation mode setting unit 87 sets the rotation speed level of the motor 20 according to the input third signal. Specifically, each time the third signal is input, the operation mode setting unit 87 changes the rotation speed level in the order of first level → second level → third level → fourth level → first level ···.

[0229] The operation mode setting unit 87 sets the operation mode of the electric lubricant supplier 1 to the continuous discharge mode or the fixed quantity discharge mode according to the input fourth signal. Specifically, each time the fourth signal is input, the operation mode setting unit 87 alternately switches the operation mode between the continuous discharge mode and the fixed quantity discharge mode.

[0230] The operation mode setting unit 87 outputs the set operation mode to the speed setting unit 86, the reciprocation number setting unit 83, the reciprocation number calculation unit 79, and the operation control unit 91. In FIG. 6, the arrows from the operation mode setting unit 87 to the reciprocation number setting unit 83 and the reciprocation number calculation unit 79 are omitted. The operation mode setting unit 87 outputs the set rotation speed level to the speed setting unit 86 and the display control unit 85. In FIG. 6, the arrow from the operation mode setting unit 87 to the display control unit 85 is omitted.

[0231] The speed setting unit 86 sets the target rotational speed of the motor 20 based on the input actual drawing amount, rotational speed level, and operation mode. Then, it notifies the set target rotational speed to the operation control unit 91 and the air bite detection unit 90. The rotational speed of the motor 20 is proportional to the discharge speed. The discharge speed is the speed at which the grease is discharged from the discharge port 66A, in other words, the discharge amount of grease per unit time. Therefore, setting the target rotational speed is equivalent to setting the target value of the discharge speed.

[0232] Specifically, when the operation mode is the continuous discharge mode, the speed setting unit 86 sets the target rotational speed to a value corresponding to the actual drawing amount within the setable range. The setable range is from the minimum value (for example, zero) to the maximum rotational speed corresponding to the rotational speed level. On the other hand, when the operation mode is the fixed amount discharge mode, the speed setting unit 86 maintains the target rotational speed at a constant speed (for example, the maximum rotational speed corresponding to the rotational speed level).

[0233] In the first embodiment, when the motor 20 is started, the target rotational speed is not immediately set to a predetermined set value but gradually increases toward the predetermined set value. The predetermined set value is the target rotational speed corresponding to the position of the trigger 9 in the continuous discharge mode and the aforementioned constant target rotational speed in the automatic discharge mode. However, the target rotational speed may be immediately set to the predetermined set value when the motor 20 is started.

[0234] The reciprocating count setting unit 83 sets the target number of reciprocating motions of the plunger 50 (in other words, the target number of dispensing operations) based on the input fifth and sixth signals when the operating mode is quantitative dispensing mode. Specifically, each time the fifth signal is input, the reciprocating count setting unit 83 increases the target number of reciprocating motions by one from the current value. Each time the sixth signal is input, the reciprocating count setting unit 83 decreases the target number of reciprocating motions by one from the current value. The target number of reciprocating motions may always be maintained at the latest value. Alternatively, it may be set to an initial value (e.g., zero) each time the battery pack 15 is attached to the electric lubricant dispenser 1 (i.e., each time the control circuit 80 is started). In this first embodiment, the target number of reciprocating motions is set to, for example, one of 0 to 99. The reciprocating count setting unit 83 outputs the set target number of reciprocating motions to the reciprocating count calculation unit 79. The target number of reciprocating motions is an example of the target number of dispensing operations in the summary of the embodiment.

[0235] The plunger-related detection unit 89 receives first to third rotation signals from first to third rotation position sensors 28A to 28C. Based on the first to third rotation signals, the plunger-related detection unit 89 counts the number of rotations of the motor 20. Based on the number of rotations and the reduction ratio of the transmission mechanism 43, it is determined whether the plunger 50 has completed one reciprocation (i.e., whether one discharge operation has been performed). Each time the plunger-related detection unit 89 determines that the plunger 50 has completed one reciprocation (i.e., one discharge operation has been performed), it outputs a reciprocation determination signal to the reciprocation count calculation unit 79 and the air entrapment detection unit 90.

[0236] The plunger-related detection unit 89 may receive first and second slider position signals from the position detector 95 in place of or in addition to the first to third rotation signals. Based on the first and second slider position signals, the plunger-related detection unit 89 may determine whether the plunger 50 has completed one round trip. For example, each time the first slider position signal is received, or each time the second slider position signal is received, the unit may determine that the plunger 50 has completed one round trip and output a round trip determination signal.

[0237] The air lock detection unit 90 detects air lock when the operating mode is set to quantitative discharge mode. However, the air lock detection unit 90 may also detect air lock when the operating mode is set to continuous discharge mode. Due to various factors, gas (e.g., air or its bubbles) may enter the chamber 63. Gas may enter, for example, when attaching or detaching the cartridge. Alternatively, gas may be present in the cartridge from the beginning along with the grease.

[0238] If gas enters the chamber 63, the gas will expand and compress repeatedly as the plunger 50 moves back and forth. As a result, the check valve 64 may not open (or may not open easily) when the plunger 50 descends, and grease may not be discharged (or may not be discharged easily). Air entrapment refers to this situation, and / or the presence of gas in the chamber 63 itself, and / or the state in which the pump 60 is attempting to discharge that gas.

[0239] The air lock detection unit 90 notifies the reciprocation count calculation unit 79, the display control unit 85, the timing unit 88, and the operation control unit 91 of the air lock detection result. Specifically, the air lock detection unit 90 determines whether or not air lock has occurred each time the plunger 50 makes one reciprocation. If it determines that air lock has not occurred, it sets the air lock detection state to "not detected," and if it detects that air lock has occurred, it sets the air lock detection state to "detected." The reciprocation count calculation unit 79, the display control unit 85, the timing unit 88, and the operation control unit 91 can recognize whether or not air lock has occurred based on the set air lock detection state.

[0240] The following describes the air entrapment detection function of the air entrapment detection unit 90. Before that, we will first define the terms "motor load" and "specific load". The "motor load" is the load applied to the motor 20 from the outside. The motor load includes a first load, a second load, and a third load, as schematically shown in Figures 7 and 8. In this first embodiment, the motor load is the sum of the first to third loads.

[0241] The first load is a load generated from the plunger 50 when the plunger 50 receives pressure from the grease and is applied to the motor 20. The second load is a load generated from the slider 48 and / or plunger 50 and applied to the motor 20, independently of the aforementioned pressure, by the reciprocating motion of the slider 48 and plunger 50 itself. The second load is mainly generated by the sliding resistance (i.e., friction) between the slider 48 and the slider guide 49. The sliding resistance is affected by the aforementioned lubricating oil. The viscosity of the lubricating oil changes with temperature. Therefore, the sliding resistance changes according to the temperature of the lubricating oil. In other words, the second load changes according to the temperature of the lubricating oil. The second load may also be generated by the sliding resistance between the plunger 50 and the inner circumferential surface of the chamber 63.

[0242] The first and second loads are loads generated from the pump 60. On the other hand, the third load is a load generated from something other than the pump 60. In this first embodiment, 3. The load is caused by mechanical losses in the transmission mechanism 43 (e.g., gear friction).

[0243] As shown in Figure 8, the first load increases significantly when the plunger 50 is moving in the first direction (i.e., when grease is being discharged), and is very small or zero when the plunger 50 is moving in the second direction. For the sake of simplicity, Figure 8 shows an example where the first load is zero when moving in the second direction. This variation in the first load is repeated each time the plunger 50 completes one reciprocation. In other words, the first load fluctuates approximately periodically, with one reciprocation of the plunger 50 forming one cycle.

[0244] On the other hand, as shown in Figure 8, the second load repeats roughly the same fluctuations each time the slider 48 moves in one direction. "One direction" means from the first end to the second end and from the second end to the first end within the round-trip range. In other words, the second load fluctuates roughly periodically, with the one-way movement of the slider 48 (i.e., the one-way movement of the plunger 50) forming one period.

[0245] The third load is constant or nearly constant, at least for typical continuous discharge times (e.g., a few seconds to tens of seconds, or in some cases, several minutes). During the two-round cycle period shown in Figure 8, the third load is constant.

[0246] The "specific load" is a part of the motor load. The specific load includes the first load but does not include at least a part of the second load. In this first embodiment, the specific load further includes the third load. In this first embodiment, the specific load does not include most of the second load, or does not include the second load at all. The specific load can be said to be the motor load with some or all of the second load removed. Figure 8 shows an example where the third load is larger than the first and second loads, but if the third load is much smaller than the first and second loads, the specific load can be considered to be the first load with some of the second load added, or equal to the first load.

[0247] Air lock can be detected, for example, based on the actual rotational speed itself or the motor current value (hereinafter referred to as "motor current value"). For example, as is clear from comparing Figures 9 and 11, or from comparing Figures 10 and 12, the fluctuations in actual rotational speed and motor current value are smaller in the air lock state than in the normal state. The normal state is a state in which no air lock occurs, and the air lock state is a state in which air lock occurs. Therefore, it is possible to detect the occurrence of air lock based on the magnitude of the fluctuation in actual rotational speed or the magnitude of the fluctuation in motor current value. Note that each of the multiple "plunger one-reciprocation timings" in Figures 9 to 12 is the timing when the plunger 50 reaches a predetermined position (e.g., the highest position) in its one reciprocation. The same applies to the "plunger one-reciprocation timings" in Figures 13, 14, 23, and 24.

[0248] However, the actual rotational speed and motor current values ​​include components caused by the second load. Moreover, as mentioned above, this second load can fluctuate with temperature. Therefore, it is not easy to accurately detect air lock based on the actual rotational speed or motor current value itself over a wide temperature range. For example, as illustrated in Figure 10, even under normal conditions, fluctuations decrease at higher temperatures. On the other hand, as illustrated in Figure 11, even under air lock conditions, fluctuations increase at lower temperatures. As a result, the difference between the magnitude of fluctuation under normal conditions and high temperatures (see Figure 10) and the magnitude of fluctuation under air lock conditions and low temperatures (see Figure 11) becomes small. Therefore, there is a possibility of mistakenly identifying air lock conditions under normal conditions and high temperatures, and a possibility of mistakenly identifying normal conditions under air lock conditions and low temperatures.

[0249] Therefore, in this first embodiment, the control circuit 80 (air lock detection unit 90) detects air lock based on the actual operating amount of the electric lubricant dispenser 1. The actual operating amount depends on the magnitude of a specific load. It has a certain size. As mentioned above, the specific load includes the first load but does not include at least a part of the second load. In other words, in the specific load, the component of the second load is reduced or eliminated. Therefore, based on the actual operating amount, it is possible to perform accurate air lock detection with reduced or eliminated influence of the second load. Accordingly, the air lock detection unit 90 determines that air lock has occurred when the actual operating amount meets predetermined requirements while the motor 20 is being driven.

[0250] The actual operation amount is specifically the amplitude of the filtered physical quantity. The filtered physical quantity is obtained by reducing or removing the component caused by the second load from the load physical quantity. The load physical quantity is a physical quantity that changes according to the magnitude of the motor load. The amplitude of the filtered physical quantity has a magnitude corresponding to the magnitude of the specific load. Therefore, based on the amplitude of the filtered physical quantity, the occurrence of air biting can be detected. Since the third load is constant or almost constant, the amplitude of the filtered physical quantity is obtained by further significantly reducing or removing the component caused by the third load from the load physical quantity. Therefore, the amplitude of the filtered physical quantity is equal to or almost equal to the amplitude of the first load.

[0251] The filtered physical quantity can be calculated by various methods capable of reducing or removing the component caused by the second load from the load physical quantity. In the first embodiment, the moving average (or moving average value) of the load physical quantity is calculated as the filtered physical quantity. The load physical quantity itself includes the component caused by the second load. As described above, the second load varies periodically every one-way movement of the slider 48. Therefore, by calculating the moving average of the load physical quantity, the component caused by the second load can be significantly reduced or removed.

[0252] The operation target time for the moving average is half of the round-trip required time. The round-trip required time is the time required for the plunger 50 to make one round-trip. By calculating the average of a plurality of load physical quantities acquired during such an operation target time, the filtered physical quantity can be obtained.

[0253] The air biting detection unit 90 stores the load physical quantity every control cycle. The air lock detection unit 90 further calculates a moving average of the load physical quantities for each control cycle. Specifically, for each control cycle, it calculates the calculation time from the target rotational speed set at that time. More specifically, the air lock detection unit 90 assumes that the plunger 50 was rotating at a constant speed at the current target rotational speed. The reduction ratio from the motor 20 to the slider 48 is known. Therefore, the amount of movement of the plunger 50 per revolution of the motor 20 is known, and consequently, the amount of rotation of the motor 20 required for the plunger 50 to move half of the round-trip distance is also known. Thus, the air lock detection unit 90 can calculate the calculation time from the target rotational speed.

[0254] The air-inclusion detection unit 90 calculates the average of multiple load physical quantities stored from a time before the calculation target time up to the present, as a moving average. The air lock detection unit 90 may calculate a moving average of any load physical quantity. Examples of load physical quantities include motor current value, actual rotational speed, and load torque. In this first embodiment, the load physical quantity is, as an example, the motor current value. In other words, the air lock detection unit 90 of this first embodiment calculates a moving average of the motor current value based on the current detection signal.

[0255] The air lock detection unit 90 then determines that air lock has occurred if its moving average satisfies predetermined requirements. In this first embodiment, the predetermined requirements include that the maximum value of the amplitude of the moving average repeatedly calculated within a predetermined drive period is less than or equal to a first current threshold.

[0256] The predetermined drive period may be any period during the operation of the motor 20. In this first embodiment, the predetermined drive period is the period of one cycle of the plunger 50. During the period of one cycle, Multiple moving averages are calculated. The difference between the maximum and minimum values ​​of these multiple moving averages is the maximum amplitude. The air lock detection unit 90 determines whether or not air lock has occurred each time a predetermined driving period has elapsed (i.e., each time the plunger 50 makes one return cycle) based on the maximum amplitude of the moving average calculated during that cycle and the first current threshold.

[0257] As illustrated in Figure 13, under air-locked conditions and in a low-temperature environment, the fluctuation of the motor current value becomes large despite the presence of air lock, and the difference from the fluctuation under normal conditions becomes small. However, the moving average of the motor current value is greatly affected by the second load, and therefore its fluctuation is very small. The same applies to the actual rotational speed. That is, in a low-temperature environment, even with air lock, the fluctuation of the actual rotational speed becomes large, and the difference from the fluctuation under normal conditions becomes small. However, the moving average of the actual rotational speed is greatly affected by the second load, and therefore its fluctuation is very small.

[0258] On the other hand, under normal conditions and in a high-temperature environment, as illustrated in Figure 14, both the moving average of the motor current value and the moving average of the actual rotational speed exhibit fluctuations of a certain magnitude corresponding to the pressure from the grease. As is clear from a comparison with Figure 13, these fluctuations are considerably larger than those under air-entrained conditions and in a low-temperature environment.

[0259] Although not shown in the diagram, the load torque applied to the motor 20 also includes a component due to the second load, but the moving average of the load torque significantly reduces the influence of the second load. Therefore, the fluctuation of the load torque, like the fluctuation of the motor current value, is considerably larger in the normal state than in the air-locked state.

[0260] Therefore, by using a moving average of the motor current value, air lock can be detected accurately over a wide temperature range. Similarly, detection can be performed with high accuracy using a moving average of the actual rotational speed and a moving average of the load torque. In the second embodiment described later, air lock detection based on a moving average of the actual rotational speed is exemplified, and in the third embodiment described later, air lock detection based on a moving average of the load torque is exemplified.

[0261] The first current threshold may be determined to be smaller than the range of the moving average of the motor current values ​​expected under normal conditions (e.g., its minimum value) and larger than the range of the same moving average expected under air entrapment conditions (e.g., its maximum value). The first current threshold may be determined in any way.

[0262] The first current threshold may be a constant value, or it may be set to a variable value depending on the operating state of the electric lubricant dispenser 1. In this first embodiment, the first current threshold is set to a variable value depending on the operating state.

[0263] In this first embodiment, the operating state includes the target rotational speed. That is, the air entrapment detection unit 90 sets a first current threshold according to the current target rotational speed notified by the speed setting unit 86.

[0264] As the target rotational speed changes, the moving average of the motor current value also changes accordingly. The moving average of the motor current value tends to increase as the target rotational speed increases. Also, the lower the target rotational speed, the more the fluctuation of the actual rotational speed is suppressed by the speed feedback control, and this reduces the fluctuation of the motor current value. However, in the high-speed range, the inertial force of the pump 60 becomes large. Therefore, in the high-speed range, the fluctuation of the motor current value actually decreases as the actual rotational speed increases.

[0265] Therefore, the first current threshold is, for example, (i) in the low to medium speed range, when the target rotational speed is high (ii) The first current threshold may be set to increase as the target rotational speed increases, and (ii) in the high-speed range, the first current threshold may be set to decrease as the target rotational speed increases. More specifically, the first current threshold may be set according to the target rotational speed, as illustrated in Figure 15.

[0266] The operating state may include the actual rotational speed. In other words, the first current threshold may be set according to the actual rotational speed itself. In that case, the first current threshold may be set in the same way as the setting method according to the target rotational speed. For example, the horizontal axis in Figure 15 may be interpreted as the actual rotational speed.

[0267] Furthermore, the operating state may include the duty cycle described above. In other words, the first current threshold may be set according to the duty cycle. The first current threshold may change in any way according to the duty cycle. For example, the first current threshold may be set so that it increases as the duty cycle increases. Alternatively, for example, the first current threshold may be set in a manner similar to the setting method according to the target rotational speed. For example, the horizontal axis in Figure 15 may be interpreted as the duty cycle.

[0268] Furthermore, the operating state may include the equipment temperature. In other words, the first current threshold may be set according to the equipment temperature. The equipment temperature is the temperature of the electric lubricant dispenser 1. Specifically, the equipment temperature may be the temperature of the grease, or a temperature that indirectly indicates the temperature of the grease.

[0269] The viscosity of the grease changes with temperature. For example, as the temperature of the grease increases, the viscosity of the grease decreases. When the viscosity of the grease decreases, the first load decreases (and consequently the motor load decreases), and the amplitude of the moving average of the motor current value decreases. For this reason, the first current threshold may be set such that, for example, the first current threshold decreases as the temperature of the grease increases. The air entrapment detection unit 90 may set the first current threshold according to the temperature detected by the temperature sensor 100.

[0270] The timing unit 88 measures the duration of air lock when air lock occurs. The duration of air lock is the time during which air lock persists. Specifically, the timing unit 88 starts measuring the duration of air lock when the air lock detection state changes from "not detected" to "detected". Specifically, it accumulates (cumulatively) one count value at a time for each control cycle, and when the duration of air lock reaches a predetermined time (i.e., when the count value reaches a predetermined value), it notifies the operation control unit 91 that air lock has persisted for a predetermined time. Specifically, the timing unit 88 sets the air lock persistence state to "detected".

[0271] The reciprocating count calculation unit 79 calculates the actual number of reciprocating motions of the plunger 50 when the operating mode is the quantitative discharge mode. However, the reciprocating count calculation unit 79 may also calculate the actual number of reciprocating motions when the operating mode is the continuous discharge mode. The actual number of reciprocating motions is the actual number of times the plunger 50 has reciprocated. In other words, the actual number of reciprocating motions is the number of times the discharge operation has actually been performed. Therefore, the actual number of reciprocating motions can be rephrased as the actual number of discharges. The actual number of reciprocating motions is an example of the actual number of discharges in the summary of the embodiment.

[0272] The round trip count calculation unit 79 accumulates the actual number of round trips each time it receives a round trip determination signal from the plunger-related detection unit 89 (i.e., each time the plunger 50 makes one round trip). Specifically, each time the round trip count calculation unit 79 receives a round trip determination signal, it updates the actual number of round trips to a value that is "1" higher than the current value.

[0273] However, the round trip count calculation unit 79 does not update the actual round trip count while air entrapment is detected by the air entrapment detection unit 90 (i.e., while the air entrapment detection state is set to "detected"). In other words, the accumulation of the actual number of round trips is temporarily stopped. Then, when the air lock is resolved and the air lock detection status is set to "not detected", the accumulation of the actual number of round trips is resumed from the value at the time of the pause.

[0274] The round-trip count calculation unit 79 notifies the display control unit 85 of the current actual number of round trips. Furthermore, the round-trip count calculation unit 79 outputs the remaining number of round trips to the operation control unit 91. The remaining number of round trips is the difference between the target number of round trips and the current actual number of round trips.

[0275] In continuous discharge mode, the operation control unit 91 commands the motor drive control unit 92 to drive the motor 20 while the trigger switch 8 is ON. Specifically, the operation control unit 91 outputs a drive command to the motor drive control unit 92 and notifies it of the current target rotational speed. The drive command requests that the motor 20 be driven.

[0276] In quantitative dispensing mode, the motion control unit 91 commands the motor drive control unit 92 to drive the motor 20 while the trigger switch 8 is ON. Specifically, the motion control unit 91 outputs a drive command to the motor drive control unit 92 and notifies it of the current target rotational speed. When the remaining number of reciprocations notified by the reciprocation count calculation unit 79 reaches zero, the motion control unit 91 stops outputting the drive command and stops the motor 20.

[0277] When operating in quantitative discharge mode, if the timing unit 88 detects a continuous air lock condition (i.e., if air lock occurs for a predetermined period of time), the operation control unit 91 stops the output of the drive command and stops the motor 20, even if the trigger switch 8 is ON and the remaining number of reciprocations has not yet reached zero.

[0278] The motor drive control unit 92 calculates the rotational position (specifically the electrical angle) and actual rotational speed of the motor 20 based on the first to third rotational signals from the first to third rotational position sensors 28A to 28C.

[0279] The motor drive control unit 92 performs speed feedback control when it receives a drive command and a target rotational speed from the motion control unit 91. Specifically, the motor drive control unit 92 calculates the speed deviation, which is the difference between the target rotational speed and the actual rotational speed. The motor drive control unit 92 then calculates the duty cycle required to make the speed deviation zero (i.e., to make the actual rotational speed match the target rotational speed). It then outputs a drive control signal to each of the two target switches to turn on. The target switches are two of the first to sixth switches Q1 to Q6, corresponding to the rotational position. At least one of the drive control signals to the target switches is a pulse width modulated signal with the calculated duty cycle. Therefore, the higher the duty cycle, the greater the power supplied to the motor 20.

[0280] The display control unit 85 displays the rotation speed level input from the operation mode setting unit 87 on the first display screen 74. The display control unit 85 displays the actual number of reciprocations input from the reciprocation count calculation unit 79 on the set reciprocation count display screen 75. The display control unit 85 executes notification processing when it is notified that air lock has occurred. The notification processing notifies the user that air lock has occurred. The notification processing may be performed in any way. The notification processing may be performed in a way that allows the user to visually and / or audibly recognize that air lock has occurred. In the first embodiment, air lock is notified by flashing the second display screen 75A and the third display screen 75B. Alternatively, the display control unit 85 may notify air lock by displaying a preset number, symbol, character, etc. on the second display screen 75A and the third display screen 75B. The display control unit 85 is an example of a notification unit in the summary of the embodiment.

[0281] (2-1-6) Main Processing The main processing performed by the control circuit 80 (more specifically, the CPU 80A) to realize various functions in quantitative dispensing mode will be explained with reference to Figure 16. When the control circuit 80 is set to quantitative dispensing mode, it performs the main processing shown in Figure 16.

[0282] When the control circuit 80 starts the main process, it determines in S110 whether the trigger switch 8 is ON or OFF. If the trigger switch 8 is OFF, the process proceeds to S120. In S120, the control circuit 80 executes the stop-down process. Details of the stop-down process are shown in Figure 17.

[0283] When the control circuit 80 transitions to the stop processing, it stops the motor 20 in S210. Specifically, the motion control unit 91 stops outputting the drive command. In S220, the control circuit 80 determines whether the current remaining number of reciprocations is zero. If the remaining number of reciprocations is not zero, the process proceeds to S240. In this case, the current remaining number of reciprocations is maintained. If the remaining number of reciprocations is zero, the process proceeds to S230. An example of a case where the remaining number of reciprocations is zero in S220 may include the case where the motor 20 is automatically stopped after the target number of reciprocations of the plunger 50 is completed, and the user then turns off the trigger 9. In S230, the control circuit 80 resets the actual number of reciprocations to an initial value (e.g., zero).

[0284] In S240, the control circuit 80 determines whether or not a change operation has been performed to modify the target number of round trips. The change operation includes turning on the second switch 72 or the third switch 73. If no change operation has been performed, the process proceeds to S270. If a change operation has been performed, the process proceeds to S250.

[0285] In S250, the control circuit 80 resets the actual number of round trips to its initial value. In S260, the control circuit 80 changes the target number of round trips according to the modification operation. In S270, the control circuit 80 determines whether a speed change operation has been performed. The speed change operation includes turning on the first switch 71. If no speed change operation has been performed, the process proceeds to S290. If a speed change operation has been performed, the process proceeds to S280. In S280, the control circuit 80 changes the rotation speed level (i.e., changes the maximum rotation speed) in accordance with the speed change operation.

[0286] In S290, the control circuit 80 sets the air lock persistence state to "not detected". The control circuit 80 further sets (resets) the air lock persistence time to zero. After processing in S290, the process moves on to S140 (Figure 16).

[0287] If the trigger switch 8 is turned on in S110, the process proceeds to S130. In S130, the control circuit 80 executes the in-operation processing. Details of the in-operation processing are shown in Figure 18.

[0288] When the control circuit 80 transitions to the operation process, in S310 it determines whether the air lock-in state is set to "detected". If the air lock-in state is not set to "detected", the process proceeds to S320. In S320, the control circuit 80 determines whether the current remaining number of reciprocations is greater than 0. If the remaining number of reciprocations is 0, the control circuit 80 stops driving the motor 20 in S410, similar to S210. A remaining number of reciprocations of 0 corresponds to the discharge operation having been performed for the target number of reciprocations. After S410, the process proceeds to S420.

[0289] In S320, if the remaining number of circumferences is greater than 0, the process proceeds to S330. A remaining number of circumferences greater than 0 corresponds to the fact that the actual number of circumferences has not yet reached the target number of circumferences. In S330, the control circuit 80 operates at a target rotational speed corresponding to the current rotational speed level. The Ta20 is driven. That is, the aforementioned speed feedback control is performed.

[0290] In S340, the control circuit 80 determines whether the plunger 50 has completed one round trip. In S350, the control circuit 80 performs an air lock detection process. The air lock detection process is a process to detect whether or not an air lock has occurred. Details of the air lock detection process are shown in Figure 19.

[0291] When the control circuit 80 moves to the air entrapment detection process, in S510 it acquires the motor current value and stores it in the semiconductor memory 80B. In S520, the control circuit 80 calculates the time to be used for calculating the moving average (i.e., half of the round trip time) based on the current target rotational speed, for example, using the method described above.

[0292] In S530, the control circuit 80 calculates a moving average of the motor current values ​​based on the calculation time calculated in S520. Specifically, it calculates the average of multiple motor current values ​​acquired and stored from before the calculation time to the present as a moving average. The control circuit 80 further updates the maximum moving average or minimum moving average based on the calculated moving average. The maximum moving average and minimum moving average are (i) reset each time the plunger 50 completes one round trip, and (ii) updated each time S530 is executed after the reset. Specifically, if the latest moving average calculated in this S530 is greater than the currently held maximum moving average, the maximum moving average is updated to the latest moving average. If the latest moving average calculated in this S530 is less than the currently held minimum moving average, the minimum moving average is updated to the latest moving average.

[0293] In S540, the control circuit 80 determines whether the plunger 50 has completed one reciprocal motion based on the result of the determination in S340. If the plunger 50 has not yet completed one reciprocal motion, the process proceeds to S550. In S550, the control circuit 80 maintains the current air entrapment detection state ("detected" or "not detected"). After processing in S550, the process proceeds to S360 (Figure 18).

[0294] In S540, if the plunger 50 completes one round trip, the process proceeds to S560. In S560, the control circuit 80 sets the first current threshold. Specifically, as described above, the control circuit 80 sets the first current threshold based on the target rotational speed, duty cycle, actual rotational speed, or equipment temperature.

[0295] In S570, the control circuit 80 determines whether the maximum amplitude of the moving average of the motor current values ​​(i.e., the maximum value of the moving average amplitude during the previous round trip period) is greater than the first current threshold. The maximum amplitude is the difference between the currently held maximum moving average and minimum moving average. Each time the plunger 50 makes one round trip, S530 obtains the maximum moving average and minimum moving average for that round trip. The difference between these maximum and minimum moving averages is the maximum amplitude.

[0296] If the maximum amplitude is greater than the first current threshold, the process proceeds to S580. In this case, the control circuit 80 determines that no air lock has occurred. Therefore, in S580, the control circuit 80 sets the air lock detection state to "not detected". After processing in S580, the process proceeds to S600.

[0297] If the maximum amplitude is less than or equal to the first current threshold, the process proceeds to S590. In this case, the control circuit 80 determines that air lock has occurred. Therefore, in S590, the control circuit 80 sets the air lock detection state to "detected". After processing in S590, the process proceeds to S600.

[0298] In S600, the control circuit 80 resets the currently held maximum moving average and minimum moving average. The control circuit 80 further resets the determination result in S340 that the plunger 50 has completed one round trip, and restarts the determination of whether or not the plunger 50 has completed one round trip. Therefore, when the plunger 50 completes another round trip from the timing of this restart, S340 will again determine that the plunger 50 has completed one round trip. After processing in S600, this process moves on to S360 (Figure 18).

[0299] In S360, the control circuit 80 determines whether the plunger 50 has completed one round trip based on the determination result in S340. If the plunger 50 has not completed one round trip, the process proceeds to S420. If the plunger 50 has completed one round trip, the process proceeds to S370.

[0300] In S370, the control circuit 80 determines whether the air lock detection state is set to "detected". If the air lock detection state is set to "detected", that is, if air lock has occurred, the process proceeds to S400. In S400, the control circuit 80 starts the notification process described above. That is, it notifies the user that air lock has occurred. After the processing in S400, the process proceeds to S420.

[0301] In S370, if the air lock detection status is not set to "detected," that is, if no air lock has occurred, the process proceeds to S380. In S380, the control circuit 80 increments the actual round trip count. That is, it adds "1" to the current actual round trip count. In S390, if the notification process is being executed, the control circuit 80 terminates that notification process. After the processing in S390, the process proceeds to S420.

[0302] Furthermore, if the air lock detection status in S370 is set to "Detected," the actual number of reciprocations is not incremented, and the current actual number of reciprocations is maintained. In other words, as long as air lock is detected, the actual number of reciprocations does not change even if the plunger 50 makes one reciprocation.

[0303] If the air lock condition is set to "detected" in S310, the process proceeds to S430. In S430, the control circuit 80 stops the motor 20 from running, similar to S210. After the process in S430, the process proceeds to S140 (Figure 16).

[0304] In S420, the control circuit 80 executes a continuation determination process. Details of the continuation determination process are shown in Figure 20. When the control circuit 80 moves to the continuation determination process, in S610 it determines whether the air lock detection state is set to "detected". If the air lock detection state is not set to "detected", that is, if no air lock has occurred, this process moves to S620.

[0305] In S620, the control circuit 80 resets the air-entry duration to zero. After processing in S620, the process proceeds to S140 (Figure 16). In S610, if the air lock detection state is set to "detected," that is, if air lock has occurred, the process proceeds to S630. In S630, the control circuit 80 accumulates the duration of the air lock. In other words, it accumulates (cumulatively) one of the aforementioned count values ​​used for measurement.

[0306] In S640, the control circuit 80 determines whether the duration of air lock is greater than or equal to a predetermined time (i.e., the count value is greater than or equal to a predetermined value). If the duration of air lock is less than the predetermined time, the process proceeds to S140 (Figure 16). If the duration of air lock is greater than or equal to the predetermined time, the process proceeds to S650.

[0307] In S650, the control circuit 80 sets the air lock-in state to "detected". In other words, it determines that the air lock-in has been occurring for a predetermined time or longer. After S650, this process continues in S14. Transition to 0 (Figure 16).

[0308] In S140, the control circuit 80 calculates (i.e., updates) the remaining number of round trips. Specifically, it subtracts the current actual number of round trips from the current target number of round trips. Then, it updates the remaining number of round trips to the result of that subtraction.

[0309] In S150, the control circuit 80 determines whether the current actual number of reciprocations is zero. If the actual number of reciprocations is not zero, the process proceeds to S160. In this case, the plunger 50 has already made at least one reciprocation in quantitative dispensing mode. Therefore, in S160, the control circuit 80 displays the current actual number of reciprocations on the set count display screen 75. This allows the user to recognize how far the grease has been dispensed. After processing in S160, the process proceeds to S110.

[0310] If the actual number of round trips is zero in S150, the process proceeds to S170. In this case, for example, it is possible that trigger 9 has not yet been manually operated, or that trigger 9 has been manually operated but the actual number of round trips has not yet reached one. Therefore, in S170, the control circuit 80 displays the target number of round trips on the set count display screen 75. This allows the user to recognize the target number of round trips. After the processing in S160, the process proceeds to S110.

[0311] Here, we will briefly explain the correspondence between the processes in Figures 16 to 20 and Figure 6. S110, S310, and S320 correspond to the processes performed by the operation control unit 91. S210, S330, S410, and S430 correspond to the processes performed by the operation control unit 91 and the motor drive control unit 92. S140, S220, S230, S250, and S380 correspond to the processes performed by the round-trip count calculation unit 79. S240 and S260 correspond to the processes performed by the round-trip count setting unit 83. S270 and S280 correspond to the processes performed by the operation mode setting unit 87. S290 and S420 correspond to the processes performed by the timing unit 88. S340 and S360 correspond to the processes performed by the plunger-related detection unit 89. S350 corresponds to the processes performed by the air-entanglement detection unit 90. S370 corresponds to the processes performed by the round-trip count calculation unit 79 and the display control unit 85. S150-S170, S390, and S400 correspond to processing by the display control unit 85.

[0312] [2-2. Second Embodiment] Another example of the air entrapment detection process will be described as a second embodiment. The electric lubricant dispenser of this second embodiment is basically configured the same as the electric lubricant dispenser 1 of the first embodiment, except for the air entrapment detection process. In other words, the processes shown in Figures 16 to 18 and Figure 20 are performed in this second embodiment as well. The configurations that differ from the first embodiment will be described below.

[0313] The difference between this second embodiment and the first embodiment lies in the load physical quantity used for calculating the moving average. In the first embodiment, the load physical quantity was the motor current value. In contrast, the load physical quantity in this second embodiment is the actual rotational speed of the motor 20. The actual rotational speed can fluctuate periodically during the operation of the pump 60. In other words, an amplitude of the actual rotational speed occurs during the operation of the pump 60. This amplitude differs between the normal state and the air-entrained state. Furthermore, the amplitude of the actual rotational speed includes a component caused by the second load.

[0314] Therefore, in this second embodiment, the air lock detection unit 90 calculates a moving average of the actual rotational speed. The calculation period for the moving average is the same as in the first embodiment. The air lock detection unit 90 determines that air lock has occurred when the moving average satisfies predetermined requirements. In this second embodiment, the predetermined requirements include that the maximum value of the amplitude of the moving average repeatedly calculated during a predetermined drive period is less than or equal to a first speed threshold. The predetermined drive period is the period of one round trip of the plunger 50, as in the first embodiment.

[0315] The first speed threshold may be determined to be a value smaller than the range of the moving average of the actual rotational speed expected under normal conditions (e.g., its minimum value) and larger than the range of the same moving average expected under air entrapment conditions (e.g., its maximum value).

[0316] The first speed threshold may be a constant value, but in this second embodiment, similar to the first current threshold in the first embodiment, it is set variably according to the operating state of the electric lubricant dispenser 1. Specifically, the first speed threshold may be set according to the target rotational speed. More specifically, the first speed threshold may be set in the same way as the first current threshold. For example, the vertical axis in Figure 15 may be interpreted as the first speed threshold. Alternatively, for example, the first speed threshold may be set in the same manner as the first current threshold, according to various operating conditions such as actual rotational speed, duty cycle, or equipment temperature.

[0317] To achieve this type of air lock detection, in this second embodiment, at S350 in Figure 18, the air lock detection process shown in Figure 21 is executed instead of the air lock detection process shown in Figure 19.

[0318] The air-entry detection process in Figure 21 differs from the air-entry detection process in Figure 19 in the following ways: (i) S511 is executed instead of S510, (ii) S531 is executed instead of S530, (iii) S561 is executed instead of S560, and (iv) S571 is executed instead of S570. Processes that are the same as those in the air-entry detection process in Figure 19 are denoted by the same reference numerals as in Figure 19, and their detailed explanations are omitted.

[0319] In S511, the control circuit 80 calculates the current actual rotational speed and stores it in the semiconductor memory 80B. In S531, the control circuit 80 calculates a moving average of the actual rotational speed based on the calculation time calculated in S520. Specifically, it calculates the average of multiple actual rotational speeds calculated and stored from before the calculation time to the present as a moving average. The control circuit 80 further updates the maximum moving average or the minimum moving average, similar to the first embodiment.

[0320] In S561, the control circuit 80 sets a first speed threshold. Specifically, as described above, the control circuit 80 sets the first speed threshold based on the target rotational speed, duty cycle, actual rotational speed, or equipment temperature.

[0321] In S571, the control circuit 80 determines whether the maximum amplitude of the moving average of the actual rotational speed is greater than the first speed threshold. If the maximum amplitude is greater than the first speed threshold, the process proceeds to S580. In this case, the control circuit 80 determines that no air lock has occurred and sets the air lock detection state to "not detected". If the maximum amplitude is less than or equal to the first speed threshold, the process proceeds to S590. In this case, the control circuit 80 determines that air lock has occurred and sets the air lock detection state to "detected".

[0322] [2-3. Third Embodiment] Another example of the air entrapment detection process will be described as a third embodiment. The electric lubricant dispenser of this third embodiment is basically configured the same as the electric lubricant dispenser 1 of the first embodiment, except for the air entrapment detection process. In other words, the processes shown in Figures 16 to 18 and Figure 20 are performed in this third embodiment as well. The configuration that differs from the first embodiment will be described below.

[0323] The difference between this third embodiment and the first embodiment lies in the load physical quantity used for calculating the moving average. Specifically, the load physical quantity in this third embodiment is the load torque of the motor 20. The load torque is the torque applied to the motor 20 from an external source.

[0324] The load torque may fluctuate periodically during the operation of pump 60. In other words, an amplitude of load torque occurs during the operation of pump 60. This amplitude differs between normal conditions and air-entrained conditions. Furthermore, the amplitude of the load torque includes a component originating from the second load.

[0325] The load torque may be obtained in any way. The air lock detection unit 90 of this third embodiment calculates (i.e., estimates) the load torque based on the above-described equation (1). The air lock detection unit 90 can obtain the motor current value based on the current detection signal and calculate the motor acceleration from the actual rotational speed. Furthermore, the motor torque coefficient and moment of inertia can be identified theoretically or experimentally and are known. Therefore, the load torque can be calculated from equation (1).

[0326] The air lock detection unit 90 calculates the load torque and then calculates a moving average of that load torque. It then determines that air lock has occurred if the moving average satisfies predetermined requirements. In this third embodiment, the predetermined requirements include that the maximum value of the amplitude of the moving average repeatedly calculated during a predetermined drive period is less than or equal to a first torque threshold. The predetermined drive period may be any period during the operation of the motor 20. In this third embodiment, the predetermined drive period is the period of one cycle of the plunger 50, as in the first embodiment.

[0327] The first torque threshold may be determined to be smaller than the range of the moving average of the load torque expected under normal conditions (e.g., its minimum value) and larger than the range of the moving average of the load torque expected under air entrapment conditions (e.g., its maximum value).

[0328] The first torque threshold may be a constant value, but in this third embodiment, similar to the first current threshold in the first embodiment, it is set variably according to the operating state of the electric lubricant dispenser 1. Specifically, the first torque threshold may be set according to the target rotational speed. More specifically, the first torque threshold may be set in the same way as the first current threshold. For example, the vertical axis in Figure 15 may be interpreted as the first torque threshold. Alternatively, the first torque threshold may be set in the same manner as the first current threshold, according to various operating conditions such as actual rotational speed, duty cycle, or equipment temperature.

[0329] To achieve this type of air lock detection, in this third embodiment, at S350 in Figure 18, the air lock detection process shown in Figure 22 is executed instead of the air lock detection process shown in Figure 19.

[0330] The air-entry detection process in Figure 22 differs from the air-entry detection process in Figure 19 in the following ways: (i) S512 and S513 are executed instead of S510; (ii) S501 is executed before S512; (iii) S532 is executed instead of S530; (iv) S562 is executed instead of S560; and (v) S572 is executed instead of S570. Processes that are the same as those in the air-entry detection process in Figure 19 are denoted by the same reference numerals as in Figure 19, and their detailed explanations are omitted.

[0331] In S501, the control circuit 80 calculates the current actual rotational speed and calculates the motor acceleration based on that actual rotational speed. In S512, the control circuit 80 acquires the motor current value based on the current detection signal.

[0332] In S513, the control circuit 80 calculates the load torque based on equation (1) using the motor acceleration and motor current values ​​obtained in S501 and S512. Furthermore, the calculated load torque is stored in the semiconductor memory 80B.

[0333] In S532, the control circuit 80 calculates a moving average of the load torque based on the calculation target time calculated in S520. Specifically, it calculates and records the period from before the calculation target time to the present. The average of the multiple load torques is calculated as a moving average. The control circuit 80 further updates the maximum moving average or the minimum moving average, similar to the first embodiment.

[0334] In S562, the control circuit 80 sets the first torque threshold. Specifically, as described above, the control circuit 80 sets the first torque threshold based on the target rotational speed, duty cycle, actual rotational speed, or equipment temperature.

[0335] In S572, the control circuit 80 determines whether the maximum amplitude of the moving average of the load torque is greater than the first torque threshold. If the maximum amplitude is greater than the first torque threshold, the process proceeds to S580. In this case, the control circuit 80 determines that no air lock has occurred and sets the air lock detection state to "not detected". If the maximum amplitude is less than or equal to the first torque threshold, the process proceeds to S590. In this case, the control circuit 80 determines that air lock has occurred and sets the air lock detection state to "detected".

[0336] [2-4. Fourth Embodiment] Another example of the air-entry detection process will be described as a fourth embodiment. The electric lubricant dispenser of this fourth embodiment is basically configured the same as the electric lubricant dispenser 1 of the first embodiment, except for the air-entry detection process. In other words, the processes shown in Figures 16 to 18 and Figure 20 are performed in this fourth embodiment as well. The configuration that differs from the first embodiment will be described below.

[0337] Prior to explaining the air entrapment detection process, the period during which the plunger 50 moves in one direction (i.e., from the second end to the first end of the movement path) is referred to as the first period, and the period during which it moves in the second direction (i.e., from the first end to the second end of the movement path) is referred to as the second period. Furthermore, the evaluation value indicating the magnitude of the load physical quantity in the first period is referred to as the first level, and the evaluation value indicating the magnitude of the load physical quantity in the second period is referred to as the second level. The first level indicates the level of the load physical quantity during the first period, and the second level indicates the level of the load physical quantity during the second period. The first and second levels may be expressed using any numerical values. In this fourth embodiment, the first and second levels are average or maximum values. That is, the first level is the average or maximum value of the load physical quantity in the first period, and the second level is the average or maximum value of the load physical quantity in the second period.

[0338] In the fourth embodiment as well, the air entrapment detection unit 90 determines that air entrapment has occurred based on the fact that the actual operating amount meets predetermined requirements while the motor 20 is being driven. The fourth embodiment differs from the first to third embodiments in terms of the actual operating amount and predetermined requirements.

[0339] In the first to third embodiments, the actual operating quantity was the amplitude of the filtered physical quantity (specifically, the moving average of the load physical quantity). In contrast, the actual operating amount in this fourth embodiment is the round-trip difference based on the physical load quantity during one round-trip period of the plunger 50. The round-trip difference is the difference between the first level and the second level during one round-trip period.

[0340] The air entrainment detection unit 90 may calculate the round-trip difference based on any load physical quantity. In this fourth embodiment, the load physical quantity is the motor current value, as in the first embodiment. That is, the first level is the average or maximum value of the motor current value during the first period, and the second level is the average or maximum value of the motor current value during the second period. The difference between these first and second levels is the round-trip difference.

[0341] In this fourth embodiment, the air entrapment detection unit 90 calculates the reciprocating difference during each reciprocating cycle of the plunger 50. It then determines that air entrapment has occurred if the reciprocating difference satisfies predetermined requirements. In this fourth embodiment, the predetermined requirements are that the reciprocating difference is This includes the condition that the current threshold is 2 or less.

[0342] As illustrated in Figure 8, the second load fluctuates approximately periodically, with one cycle being the one-way movement of the slider 48. Therefore, calculating the round-trip difference is equivalent to reducing or eliminating the component caused by the second load. Thus, by comparing the round-trip difference with the second current threshold, the influence of the second load can be suppressed or eliminated, and air entrapment can be detected with high accuracy. Furthermore, since the third load is constant or nearly constant, the component caused by the third load is also significantly reduced or eliminated in the round-trip difference.

[0343] The air entrapment detection unit 90 can detect in which direction the plunger 50 is moving (i.e., whether it is currently the first period or the second period) based on the first and second slider position signals from the position detector 95.

[0344] The position detector 95 may be comprised of only one of the first and second detectors 95A and 95B. For example, if only the first detector 95A is provided, the air lock detection unit 90 can determine (i.e. detect) the position of the plunger 50 based on the first slider position signal and the first to third rotation signals. Specifically, upon receiving the first slider position signal, the air lock detection unit 90 determines that the plunger 50 has reached its lowest position (the fourth state described above) at the time of receiving the signal. After receiving the first slider position signal, the air lock detection unit 90 detects the amount of rotation (i.e., rotation angle) of the motor 20 after receiving the first slider position signal, based on the first to third rotation signals. The amount of rotation of the motor 20 required to move from the first end to the second end of the reciprocating movement range is known, for example, N rotations. Therefore, in response to the motor 20 rotating N times after receiving the first slider position signal, the air entrapment detection unit 90 recognizes that the plunger 50 has reached its uppermost position (the second state described above). In this way, the air entrapment detection unit 90 can recognize the timing when the plunger 50 reaches its uppermost and lowermost positions, recognize the first and second periods based on these timings, and calculate the first and second levels based on these first and second periods.

[0345] The air lock detection unit 90 acquires a first level of the motor current value during the first period (or second period), and then acquires a second level of the motor current value during the subsequent second period (or first period). Based on the completion of the second period, it calculates the round-trip difference between the immediately preceding first and second levels, and determines whether or not air lock has occurred based on this round-trip difference. Alternatively, the second period and the subsequent first period may be considered as one round trip of the plunger 50, and the round-trip difference may be calculated for each round trip.

[0346] As illustrated in Figure 23, under air-locked conditions and in a low-temperature environment, the fluctuation in motor current value becomes large despite the presence of air lock, and the difference from the fluctuation under normal conditions becomes small. However, the difference between the first and second levels of the motor current value (i.e., the round-trip difference) is very small. Note that the first and second levels in Figures 23 and 24 represent average values.

[0347] The same applies to the actual rotational speed. That is, in low-temperature environments, even if air is trapped, the fluctuation in the actual rotational speed becomes larger, and the difference in magnitude from the fluctuation under normal conditions becomes smaller. However, the difference between the first and second levels of the actual rotational speed (i.e., the difference between the two rotational speeds) is very small.

[0348] On the other hand, under normal conditions and in a high-temperature environment, as illustrated in Figure 24, both the reciprocal difference in motor current value and the reciprocal difference in actual rotational speed have a certain magnitude corresponding to the pressure from the grease. As is clear from comparing with Figure 23, this magnitude is considerably larger than the fluctuations that occur under air-entrained conditions and in a low-temperature environment.

[0349] Although not shown in the diagram, the load torque applied to the motor 20 also includes components due to the second load (and third load), but the reciprocal difference in load torque is significantly reduced by the influence of the second load (and third load). Therefore, the reciprocal difference in load torque is also sufficiently larger in the normal state than in the air-entrained state.

[0350] Therefore, by using the round-trip difference in motor current value, air entrapment can be detected accurately over a wide temperature range. Similarly, detection can be performed with high accuracy using the round-trip difference in actual rotational speed and the round-trip difference in load torque. In the fifth embodiment described later, air entrapment detection based on the round-trip difference in actual rotational speed is exemplified, and in the sixth embodiment described later, air entrapment detection based on the round-trip difference in load torque is exemplified.

[0351] The second current threshold may be determined to be smaller than the range of round-trip difference expected under normal conditions (e.g., its minimum value) and larger than the range of round-trip difference expected under air entrapment conditions (e.g., its maximum value).

[0352] The second current threshold may be a constant value, but in this fourth embodiment, similar to the first current threshold in the first embodiment, it is variably set according to the operating state of the electric lubricant dispenser 1. Specifically, the second current threshold may be set according to the target rotational speed. More specifically, the second current threshold may be set in the same way as the first current threshold. For example, the vertical axis in Figure 15 may be interpreted as the second current threshold. Alternatively, the second current threshold may be set in the same manner as the first current threshold, according to various operating conditions such as actual rotational speed, duty cycle, or equipment temperature.

[0353] To achieve this type of air lock detection, in this fourth embodiment, at S350 in Figure 18, the air lock detection process shown in Figure 25 is executed instead of the air lock detection process shown in Figure 19.

[0354] When the control circuit 80 proceeds to the air entrapment detection process shown in Figure 25, it acquires the motor current value in S710. In S720, the control circuit 80 determines whether it is currently the first period or the second period. As mentioned above, this determination can be made based on the first slider position signal and the second slider position signal, or based on the first slider position signal or the second slider position signal and the first to third rotation signals.

[0355] If the current state is the first period (i.e., the plunger 50 is moving in the first direction), the control circuit 80 updates the first level (average or maximum value) of the motor current value for that first period in S740. If the first level is the average value, the control circuit 80 calculates the average value for the first period, including the motor current value acquired this time, and replaces (i.e., updates) the currently held average value with that average value. If the first level is the maximum value, and the motor current value acquired this time is greater than the currently held maximum value, the control circuit 80 updates the motor current value acquired this time to the maximum value. After processing in S740, the process moves on to S750 (see Figure 26).

[0356] In S720, if the current time is the second period (i.e., the plunger 50 is moving in the second direction), the control circuit 80 updates the second level (average or maximum value) of the motor current value during the second period in S730 in the same manner as in S740. After processing in S730, the process moves on to S750 (see Figure 26).

[0357] In S750, the control circuit 80 determines whether the plunger 50 has completed one reciprocal motion, similar to S530 in Figure 19. If the plunger 50 has not yet completed one reciprocal motion, the process proceeds to S760. In S760, the control circuit 80 maintains the current air entrapment detection state.

[0358] In S750, if the plunger 50 completes one round trip, the process proceeds to S770. In S770, the control circuit 80 calculates the round-trip difference from the currently held first level and second level.

[0359] In the S780, the control circuit 80 sets a second current threshold. Specifically, as mentioned above, the control circuit 80 sets the second current threshold based on the target rotational speed, duty cycle, actual rotational speed, or equipment temperature.

[0360] In S790, the control circuit 80 determines whether the round-trip difference calculated in S770 is greater than the second current threshold. If the round-trip difference is greater than the second current threshold, the process proceeds to S800. In this case, the control circuit 80 determines that no air lock has occurred and sets the air lock detection state to "not detected". If the round-trip difference is less than or equal to the second current threshold, the process proceeds to S810. In this case, the control circuit 80 determines that air lock has occurred and sets the air lock detection state to "detected". After processing in S800 or S810, the process proceeds to S820.

[0361] In S820, the control circuit 80 resets the currently held first and second levels. The control circuit 80 further resets the determination result from S340 that the plunger 50 has completed one round trip, and restarts the determination of whether or not the plunger 50 has completed one round trip.

[0362] [2-5. Fifth Embodiment] Another example of the air entrapment detection process will be described as the fifth embodiment. The electric lubricant dispenser of this fifth embodiment is basically configured the same as the electric lubricant dispenser 1 of the fourth embodiment, except for a part of the air entrapment detection process. In other words, the processes shown in Figures 16 to 18 and 20 are performed in this fifth embodiment as well. The configuration that differs from the fourth embodiment will be described below.

[0363] The fifth embodiment differs from the fourth embodiment in the load physical quantity used to calculate the round-trip difference. In the fourth embodiment, the load physical quantity was the motor current value. In contrast, the load physical quantity in the fifth embodiment is the actual rotational speed of the motor 20, the same as in the second embodiment. That is, in the fifth embodiment, the first level is the average or minimum value of the actual rotational speed during the first period, and the second level is the average or minimum value of the actual rotational speed during the second period. The difference between these first and second levels is the round-trip difference.

[0364] In this fifth embodiment, the air entrapment detection unit 90 calculates the reciprocating difference based on the actual rotational speed during each reciprocating cycle of the plunger 50. It then determines that air entrapment has occurred if the reciprocating difference satisfies predetermined requirements. In this fifth embodiment, the predetermined requirements include that the reciprocating difference is less than or equal to a second speed threshold.

[0365] The second speed threshold may be a constant value. In this fifth embodiment, it is set variably according to the operating state of the electric lubricant dispenser 1 (e.g., target rotational speed, actual rotational speed, duty cycle, or equipment temperature) in the same manner as the first speed threshold in the second embodiment.

[0366] To achieve this type of air lock detection, in this fifth embodiment, at S350 in Figure 18, the air lock detection process shown in Figures 27 to 28 is executed instead of the air lock detection process shown in Figures 25 to 26.

[0367] The air-entry detection process in Figures 27-28 differs from the air-entry detection process in Figures 25-26 in that S711, S731, S741, S781, and S791 are executed instead of S710, S730, S740, S780, and S790, respectively. For processes that are the same as the detection process, the same reference numerals as in Figures 25 and 26 are used, and their detailed explanations are omitted.

[0368] In S711, the control circuit 80 calculates the current actual rotational speed. In S741, the control circuit 80 updates the first level (average or minimum value) of the actual rotational speed during the first period in the same manner as in S740 (Figure 25).

[0369] In S731, the control circuit 80 updates the second level (average or minimum value) of the actual rotational speed during the second period in the same manner as in S730 (Figure 25). In S781, the control circuit 80 sets a second speed threshold. Specifically, as described above, the control circuit 80 sets the second speed threshold based on the target rotational speed, duty cycle, actual rotational speed, or equipment temperature.

[0370] In S791, the control circuit 80 determines whether the round-trip difference calculated in S770 is greater than the second velocity threshold. If the round-trip difference is greater than the second velocity threshold, the process proceeds to S800, where it is determined that no air entrapment has occurred, and the air entrapment detection status is set to "not detected".

[0371] If the round-trip difference is less than or equal to the second velocity threshold, the process proceeds to S810, where it is determined that air has entered the system, and the air entry detection status is set to "detected". [2-6. Sixth Embodiment] Another example of the air entrapment detection process will be described as the sixth embodiment. The electric lubricant dispenser of this sixth embodiment is basically configured the same as the electric lubricant dispenser 1 of the fourth embodiment, except for a part of the air entrapment detection process. In other words, the processes shown in Figures 16 to 18 and 20 are performed in this sixth embodiment as well. The configuration that differs from the fourth embodiment will be described below.

[0372] The difference between this sixth embodiment and the fourth embodiment lies in the load physical quantity used to calculate the round-trip difference. In this sixth embodiment, the load physical quantity is the load torque of the motor 20, the same as in the third embodiment. In other words, in this sixth embodiment, the first level is the average or maximum value of the load torque during the first period, and the second level is the average or maximum value of the load torque during the second period. The difference between these first and second levels is the round-trip difference.

[0373] In this sixth embodiment, the air entrapment detection unit 90 calculates the reciprocating difference based on the load torque for each reciprocating motion of the plunger 50. It then determines that air entrapment has occurred if the reciprocating difference satisfies predetermined requirements. In this sixth embodiment, the predetermined requirements include that the reciprocating difference is less than or equal to a second torque threshold.

[0374] The second torque threshold may be a constant value. In this sixth embodiment, it is set variably according to the operating state of the electric lubricant dispenser 1 (e.g., target rotational speed, actual rotational speed, duty cycle, or equipment temperature) in the same manner as the first torque threshold in the third embodiment.

[0375] To achieve this type of air lock detection, in this sixth embodiment, at S350 in Figure 18, the air lock detection process shown in Figures 29 to 30 is executed instead of the air lock detection process shown in Figures 25 to 26.

[0376] The air-entry detection process shown in Figures 29 to 30 differs from the air-entry detection process shown in Figures 25 to 26 in that (i) S712 to S714 are executed instead of S710, and (ii) S731, S741, S781, and S791 are executed instead of S730, S740, S780, and S790, respectively. Processes that are the same as those in the air-entry detection process shown in Figures 25 to 26 are denoted by the same reference numerals as in Figures 25 to 26, and their detailed explanations are omitted.

[0377] In S712, the control circuit 80 calculates the current actual rotational speed and calculates the motor acceleration based on that actual rotational speed. In S713, the control circuit 80 acquires the motor current value based on the current detection signal.

[0378] In S714, the control circuit 80 calculates the load torque based on equation (1) above, using the motor acceleration and motor current values ​​obtained in S712 and S713. In S742, the control circuit 80 updates the first level (average or maximum value) of the load torque during the first period in the same manner as in S740 (Figure 25).

[0379] In S732, the control circuit 80 updates the second level (average or maximum value) of the load torque during the second period in the same manner as in S730 (Figure 25). In S782, the control circuit 80 sets a second torque threshold. Specifically, as described above, the control circuit 80 sets the second torque threshold based on the target rotational speed, duty cycle, actual rotational speed, or equipment temperature.

[0380] In S792, the control circuit 80 determines whether the round-trip difference calculated in S770 is greater than the second torque threshold. If the round-trip difference is greater than the second torque threshold, the process proceeds to S800, where it is determined that no air has been trapped, and the air trap detection status is set to "not detected".

[0381] If the round-trip difference is less than or equal to the second torque threshold, the process proceeds to S810, where it is determined that air has entered the system, and the air entry detection status is set to "detected". [2-7. Other Embodiments] Although embodiments of this disclosure have been described above, this disclosure is not limited to the embodiments described above and can be implemented in various modified forms.

[0382] (2-7-1) The physical load quantities used for detecting air entrapment may be different from the motor current value, actual rotational speed, and load torque. (2-7-2) The operating conditions referenced in setting each threshold, such as the first current threshold and the first speed threshold, are not limited to the operating conditions exemplified in the above embodiments (target rotational speed, duty cycle, actual rotational speed, or equipment temperature). Each threshold may be set based on any operating condition in the electric lubricant dispenser 1. The operating condition may be any that affects the motor load, that is, any condition in which the motor load may change in response to a change in the operating condition.

[0383] For example, the operating state may be the battery voltage. In other words, each threshold may be set according to the magnitude of the battery voltage. Even if the duty cycle is constant, if the battery voltage decreases, the power supplied to the motor 20 will also decrease, and the output of the motor 20 will decrease. For this reason, each threshold may be set according to the magnitude of the battery voltage. Specifically, each threshold may be set so that each threshold decreases as the battery voltage decreases. To achieve this, the electric lubricant dispenser 1 may be equipped with a voltage detector that detects the battery voltage. The voltage detector may be configured to (i) receive the battery voltage and (ii) output a voltage detection signal to the control circuit 80 according to the magnitude of that voltage. The control circuit 80 may (i) acquire the magnitude of the battery voltage based on the voltage detection signal from the voltage detector and (ii) set each threshold based on the acquired magnitude.

[0384] (2-7-3) In each of the above embodiments, examples of predetermined processes to be performed when air entrapment is detected include notification processing and temporary suspension of the accumulation of the actual number of round trips. However, if air entrapment is detected, other predetermined processes may be performed in addition to or instead of these processes. .

[0385] (2-7-4) The electric lubricant dispenser 1 may be configured to dispense lubricants other than grease. These lubricants may be, for example, semi-solid or liquid. (2-7-5) The rotation speed level, operating mode, and target number of reciprocations may be set in a manner different from that of the above embodiment. For example, a user interface (e.g., a button, dial, lever, touch panel, etc.) of a different form than the second and third switches 72 and 73 of the above embodiment may be provided for setting the operating mode. The operating mode may be switched in response to the operation of the user interface. The same applies to the target number of reciprocations. The rotation speed level may also be switched in response to the operation of a user interface (e.g., a button, dial, lever, touch panel, etc.) of a different form than the first switch 71 of the above embodiment.

[0386] (2-7-6) In the above embodiment, the rotational state of the motor 20 (i.e., rotational position and actual rotational speed) was obtained using the first to third rotational position sensors 28A to 28C. However, the rotational state may be obtained by other means. For example, so-called sensorless control may be employed in the electric lubricant dispenser 1. That is, the rotational state of the motor may be obtained based on the induced voltage generated in each of the three coils 24 of the motor 20.

[0387] [2-6. Supplementary Information] Multiple functions achieved by one component in the above embodiment may be achieved by multiple components, and one function achieved by one component may be achieved by multiple components. Also, multiple functions achieved by multiple components may be achieved by one component, and one function achieved by multiple components may be achieved by one component. Furthermore, some parts of the configuration of the above embodiment may be omitted. Also, at least some parts of the configuration of one embodiment may be added to or replaced with the configuration of another embodiment. [Explanation of Symbols]

[0388] 1...Electric lubricant dispenser, 20...Motor, 48...Slider, 49...Slider guide, 50...Plunger, 54...Tank, 60...Pump, 3...Chamber, 70...Operation panel, 80...Control circuit, 82...Drive circuit, 93...Current detector, 95...Position detector, 100...Temperature sensor, R3...Third pull-up resistor, R4...Fourth pull-up resistor.

Claims

1. Motor and, A pump comprising a housing and a reciprocating member, wherein the housing is configured to house a lubricant, and the reciprocating member is configured to (i) be at least partially located within the housing, (ii) repeatedly reciprocate in a first direction and a second direction in the opposite direction in response to the rotation of the motor, and (iii) discharge the lubricant from the housing as the reciprocating member moves in the first direction, A drive circuit configured to drive the motor, A control circuit, The drive circuit is controlled to rotate the motor, During the operation of the motor, a predetermined process is performed based on the fact that the actual operating amount, which has a magnitude corresponding to the magnitude of a specific load among the motor loads applied to the motor, satisfies a predetermined requirement indicating that gas is mixed into the housing. A control circuit configured as follows, Equipped with, The specified load includes a first load applied by the reciprocating member as the reciprocating member receives pressure from the lubricant, and does not include at least a portion of a second load applied by the reciprocating member as a result of the reciprocating member moving back and forth independently of the pressure. Electric lubricant dispenser.

2. An electric lubricant dispenser according to claim 1, The pump includes a guide that supports the reciprocating member so that it can reciprocate, The reciprocating member is configured to move along the guide. Electric lubricant dispenser.

3. An electric lubricant dispenser according to claim 2, The reciprocating member is A plunger, at least partially housed in the aforementioned housing, A slider is mechanically connected to the plunger and configured to move integrally with the plunger along the guide, An electric lubricant dispenser equipped with the following features.

4. An electric lubricant dispenser according to any one of claims 1 to 3, The actual operating amount is an electric lubricant dispenser, which includes the amplitude of a filtered physical quantity obtained by reducing or removing the component attributable to the second load from a load physical quantity, which is a physical quantity that changes according to the magnitude of the motor load.

5. An electric lubricant dispenser according to claim 4, The control circuit is configured to calculate the moving average of the load physical quantity, The filtered physical quantity is the moving average. Electric lubricant dispenser.

6. An electric lubricant dispenser according to claim 5, The aforementioned moving average is the average of the load physical quantity within the calculation period. The calculation time is half the round-trip time required for the reciprocating member to complete one round trip. Electric lubricant dispenser.

7. An electric lubricant dispenser according to claim 6, The aforementioned control circuit is Set the target rotational speed, which is the target value for the rotational speed of the motor. The drive circuit is controlled so that the actual rotational speed of the motor matches the target rotational speed. The calculation time is obtained based on the set target rotation speed. The moving average is calculated based on the acquired calculation time. An electric lubricant dispenser configured in such a way.

8. An electric lubricant dispenser according to any one of claims 4 to 7, An electric lubricant dispenser, wherein the predetermined requirement includes the condition that the maximum value of the amplitude of the filtered physical quantity within a predetermined driving period is less than or equal to a first threshold.

9. An electric lubricant dispenser according to claim 8, The control circuit is configured to change the first threshold value according to the operating state of the electric lubricant dispenser, in an electric lubricant dispenser.

10. An electric lubricant dispenser according to any one of claims 4 to 9, The drive circuit is configured to supply current to the motor and rotate the motor, The aforementioned physical load quantity includes the magnitude of the current supplied from the drive circuit to the motor. Electric lubricant dispenser.

11. An electric lubricant dispenser according to any one of claims 4 to 9, The aforementioned load physical quantity includes the actual rotational speed of the motor, in an electric lubricant dispenser.

12. An electric lubricant dispenser according to any one of claims 4 to 9, An electric lubricant dispenser, wherein the aforementioned load physical quantity includes load torque, which is torque applied to the motor from the outside.

13. An electric lubricant dispenser according to any one of claims 1 to 3, The actual operating amount includes the reciprocating difference based on the load physical quantity, which is a physical quantity that changes according to the magnitude of the motor load during the reciprocating period in which the reciprocating member makes one reciprocating motion. The aforementioned round-trip difference is the difference between a first level indicating the magnitude of the load physical quantity during the first period in which the reciprocating member is moving in the first direction, and a second level indicating the magnitude of the load physical quantity during the second period in which the reciprocating member is moving in the second direction. Electric lubricant dispenser.

14. An electric lubricant dispenser according to claim 13, The aforementioned predetermined requirement includes the condition that the reciprocating difference is less than or equal to a second threshold, in an electric lubricant dispenser.

15. An electric lubricant dispenser according to claim 14, The control circuit is configured to change the second threshold value according to the operating state of the electric lubricant dispenser, in an electric lubricant dispenser.

16. An electric lubricant dispenser according to any one of claims 13 to 15, The drive circuit is configured to supply current to the motor and rotate the motor, The aforementioned physical load quantity includes the magnitude of the current supplied from the drive circuit to the motor. The first level is the average or maximum value of the magnitude of the current during the first period. The second level is the average or maximum value of the magnitude of the current during the second period. Electric lubricant dispenser.

17. An electric lubricant dispenser according to any one of claims 13 to 15, The aforementioned physical load quantity includes the actual rotational speed of the motor. The first level is the average or minimum value of the actual rotational speed during the first period. The second level is the average or minimum value of the actual rotational speed during the second period. Electric lubricant dispenser.

18. An electric lubricant dispenser according to any one of claims 13 to 15, The aforementioned physical load quantity includes the load torque, which is the torque applied to the motor from the outside. The first level is the average or maximum value of the load torque during the first period. The second level is the average or maximum value of the load torque during the second period. Electric lubricant dispenser.

19. An electric lubricant dispenser according to any one of claims 13 to 18, The system includes a position detector configured to output a position signal corresponding to the position of the reciprocating member, The aforementioned control circuit is Upon receiving the aforementioned position signal, Based on the first level in the first period determined based on the position signal and the second level in the second period determined based on the position signal, the round-trip difference is calculated. An electric lubricant dispenser configured in such a way.

20. An electric lubricant dispenser according to claim 9 or claim 15, The aforementioned control circuit is Set the target rotational speed, which is the target value for the rotational speed of the motor. The drive circuit is controlled so that the actual rotational speed of the motor matches the target rotational speed. It is configured in such a way, The aforementioned operating state includes the aforementioned target rotational speed, Electric lubricant dispenser.

21. An electric lubricant dispenser according to claim 9 or claim 15, The control circuit is configured to control the drive circuit by outputting a pulse-width modulated signal having a duty cycle to the drive circuit. The drive circuit is configured to receive the pulse width modulated signal and drive the motor according to the received pulse width modulated signal. The aforementioned operating state includes the duty cycle, Electric lubricant dispenser.

22. An electric lubricant dispenser according to claim 9 or claim 15, The aforementioned operating state includes the actual rotational speed of the motor, and is an electric lubricant dispenser.

23. An electric lubricant dispenser according to claim 9 or claim 15, The control circuit is configured to acquire the temperature of the electric lubricant dispenser, The aforementioned operating state includes the temperature, Electric lubricant dispenser.

24. An electric lubricant dispenser according to any one of claims 1 to 23, The storage unit is equipped with a notification unit configured to notify information indicating that the gas is mixed in, The predetermined process includes broadcasting the information via the notification unit. Electric lubricant dispenser.

25. An electric lubricant dispenser according to any one of claims 1 to 24, The aforementioned control circuit is While the motor is running, the actual number of reciprocating movements of the reciprocating member is accumulated. The motor is stopped based on the fact that the actual number of round trips has reached the target number of round trips. It is configured in such a way, The predetermined process includes temporarily suspending the accumulation of the actual number of round trips. Electric lubricant dispenser.

26. An electric lubricant dispenser according to claim 25, The control circuit is configured to temporarily suspend the accumulation of the actual number of round trips, and then resume the accumulation of the actual number of round trips based on the fact that the actual amount of operation no longer meets the predetermined requirements. Electric lubricant dispenser.

27. An electric lubricant dispenser according to any one of claims 1 to 26, The control circuit is configured to stop the motor when the actual operating amount satisfies the predetermined requirements for a predetermined period of time while the motor is being driven. Electric lubricant dispenser.

28. An electric lubricant dispenser according to any one of claims 1 to 27, The control circuit is configured to detect, in response to the fulfillment of the predetermined requirements while the motor is in operation, that the gas has entered the housing and / or that the pump is about to discharge the gas. Electric lubricant dispenser.

29. A method for dispensing lubricant from an electric lubricant dispenser, The motor is used to move a reciprocating member back and forth to discharge the lubricant from the housing, During the operation of the motor, a predetermined process is performed based on the fact that the actual operating amount, which has a magnitude corresponding to a specific load among the motor loads applied to the motor, satisfies predetermined requirements indicating that gas is mixed into the housing. Equipped with, The specified load includes a first load applied by the reciprocating member as the reciprocating member receives pressure from the lubricant, and does not include at least a portion of a second load applied by the reciprocating member as a result of the reciprocating member moving back and forth independently of the pressure. method.

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