JP2011224425A - Apparatus for detecting abnormality - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide an apparatus for detecting abnormality capable of detecting abnormality of an adhesive-coating device caused by malfunction of a pump for supplying hot melt adhesive.SOLUTION: The apparatus 40 for detecting abnormality detects an actuating signal S for ejecting adhesive from a coating gun 3 by an actuating signal-detecting part 81, detects a stroke of a reciprocal pump 10 based on a detecting signal Sa of an approaching sensor 43, specifies the number C of times of ejecting action per stroke from these results as a relationship between the ejecting action of the coating gun 3 and the stroke of the reciprocal pump 10, and determines abnormality by an abnormality-determining part 86 based on the specified number C of times.

Description

  The present invention relates to an abnormality detection device applied to an adhesive application device for applying a hot melt adhesive.

  2. Description of the Related Art An adhesive application device for applying a hot melt adhesive is widely used for bonding a packaging box or the like on a production line for packaging an article such as a product. When an abnormality occurs in such an adhesive application device, there is a problem that no adhesive is applied to a predetermined portion of the packaging box or the application position of the adhesive is shifted. Therefore, in order to reduce or avoid the occurrence of such problems, it is desirable to detect an abnormality in the adhesive application device.

  For example, as an abnormality detection device applied to an adhesive application device, an operation signal for an electromagnetic valve that switches between supply and stop of compressed air that drives an application gun that injects adhesive, and a piston that injects adhesive from the application gun It is known to compare the conduction signal generated by the actual operation of the rod, measure the delay time of the conduction signal from the operation signal of the solenoid valve, and detect the abnormality of the coating gun based on the delay time (Patent Document 1).

Japanese Patent Laid-Open No. 2003-245581

  In general, the adhesive applicator is provided with a reciprocating pump for supplying an adhesive to the application gun in order to eject the adhesive from the application gun. The adhesive application device keeps the supply pressure within a sprayable range by stroking a reciprocating pump when the supply pressure of the adhesive to the application gun is reduced by injection of the adhesive. Therefore, if the pump has a malfunction, the supply pressure of the adhesive is insufficient, resulting in the same problem as when the malfunction occurs in the coating gun. However, the abnormality detection device of Patent Document 1 can detect an abnormal operation of the solenoid valve and the piston rod, which are constituent elements of the application gun, but the adhesive application due to a malfunction of the pump that supplies the adhesive to the application gun. The device abnormality cannot be detected.

  Therefore, an object of the present invention is to provide an abnormality detection device that can detect an abnormality of an adhesive application device caused by a malfunction of a pump that supplies hot melt adhesive.

  The abnormality detection device (40) according to the present invention supplies the adhesive to the injection means by using an injection means (3) capable of injecting a hot melt adhesive (Ad) and a reciprocating pump (10). An adhesive supply device (2) for causing the reciprocating pump to stroke when the supply pressure of the adhesive to the injection device is reduced by a predetermined amount due to the injection of the adhesive. The injection detection means (81) for detecting an injection operation for the injection means to inject the adhesive, the stroke detection means (43) for detecting the stroke of the reciprocating pump, and the injection detection means And an abnormality determining means (86) for determining an abnormality of the adhesive application device based on the correspondence between the jetting operation detected by the stroke and the stroke detected by the stroke detecting means. To solve the more problems described above.

  According to this abnormality detection device, an abnormality is detected based on the correspondence between the injection operation of the injection means and the stroke of the reciprocating pump, so that the reciprocation is performed despite the supply pressure being reduced by a predetermined amount due to the injection of the adhesive. It is possible to detect an abnormality of the adhesive application device due to a malfunction of the reciprocating pump such as the dynamic pump not operating.

  In addition, when a serious malfunction such as the stop of the supply of the adhesive occurs, as a phenomenon that should be said as a sign, for example, the adhesive stickiness increases or the adhesive of the adhesive by the injection means is deteriorated due to deterioration of the pump itself. The correspondence relationship between the injection of the adhesive and the stroke of the pump may change as compared to the normal time, such as the time from the injection to the time when the stroke is performed is delayed from the normal time. According to this abnormality detection device, an abnormality is determined based on the correspondence between the injection of the adhesive and the stroke of the pump. Therefore, by appropriately setting a criterion for this correspondence, before the malfunction becomes serious, It is possible to detect the above sign and determine that it is abnormal. Therefore, it is possible to prevent the occurrence of a problem that the adhesive is not injected due to a serious malfunction of the reciprocating pump.

  In one aspect of the abnormality detection device of the present invention, the abnormality determination means can determine the abnormality by acquiring the number of the injection operations per predetermined number of strokes as the correspondence relationship. The supply pressure of the adhesive decreases as the number of times of injection of the adhesive increases. Accordingly, when a malfunction occurs in the reciprocating pump, the response to the pressure reduction of the supply pressure is deteriorated, so that the number of injection operations per predetermined number of strokes is increased from the normal time. Therefore, an abnormality can be determined by grasping the number of times of the injection operation.

  For example, when the number of injection operations of the injection means detected by the injection detection means is counted and the number of times is stored as a count value, and when the stroke detection means detects the stroke a predetermined number of times Count management means (85) for resetting the count value stored in the counting means, and the abnormality determining means is configured to generate a predetermined number of strokes based on the count value stored in the counting means. The number of times of the injection operation is acquired, and the abnormality can be determined when the count value exceeds a reference value.

  As one aspect of the abnormality detection device of the present invention, the reciprocating pump includes a housing (53) in which a cylinder (52) into which a plunger (51) is reciprocally movable is formed, and an exterior of the housing. Proximity sensor (69b) that is provided in an exposed state and has a movable part (69b) that interlocks with the operation of the plunger, and that can detect the operation of the movable part in a non-contact state as the stroke detecting means. 43) may be provided. According to this aspect, in order to detect the stroke of the reciprocating pump, the movement of the movable portion that operates in conjunction with the plunger is detected by the proximity sensor, so that the stroke can be reliably detected without contacting the reciprocating pump. . In addition, since the movable part is provided in a state exposed to the outside of the housing in which the plunger is accommodated, access to the movable part is easy. Therefore, in order to provide the proximity sensor, it is not necessary to secure a mounting space on the reciprocating pump side or to modify the reciprocating pump. Therefore, the stroke of the reciprocating pump can be reliably detected with a simple configuration and without much effort.

  In addition, in the above description, in order to make an understanding of this invention easy, the reference sign of the accompanying drawing was attached in parenthesis, but this invention is not limited to the form of illustration by it.

  As described above, according to the abnormality detection device of the present invention, an abnormality is detected based on the correspondence between the injection operation of the injection means and the stroke of the reciprocating pump. It is possible to detect abnormality of the adhesive application device.

1 is an overall configuration diagram of an adhesive application device to which an abnormality detection device according to an embodiment of the present invention is applied. The longitudinal cross-sectional view which showed the principal part of the reciprocating pump. The block diagram explaining the function of the calculating part of the abnormality detection apparatus shown by FIG. The figure which showed an example of the correspondence of the injection | pouring operation | movement of an adhesive agent, and a stroke, respectively at the time of normality and abnormality.

  FIG. 1 is an overall configuration diagram of an adhesive application device to which an abnormality detection device according to an embodiment of the present invention is applied. The adhesive application device 1 is a packaging unit that injects a supply unit 2 as an adhesive supply means for supplying a hot melt adhesive (hereinafter referred to as an adhesive) in a liquid state, and an adhesive supplied from the supply unit 2. An applicator gun 3 is provided as spraying means for applying an adhesive to a coating object such as a box. The supply unit 2 and the application gun 3 are connected by a supply hose 4 that can withstand the temperature and pressure of the adhesive supplied by the supply unit 2.

  The supply unit 2 is a pump that heats the adhesive Ad with the heater 8 and stores it in the tank 9 in a liquid state, and a pump that pumps the adhesive Ad against the coating gun 3 using the reciprocating pump 10. And a controller 7 that controls the supply and stop of the compressed air that is the working fluid of the reciprocating pump 10 and controls the operation of the coating gun 3. The holding unit 5 and the pump unit 6 are connected by a connection path 11. The control unit 7 includes a compressor 12 that generates compressed air to be supplied to the reciprocating pump 10, and a control circuit 13 that controls the compressor 12 and the coating gun 3.

  The application gun 3 includes a gun body 15 that sprays the adhesive Ad and a drive unit 16 that drives the gun body 15. The gun body 15 is formed with a holding chamber 18 for holding the adhesive Ad. The holding chamber 18 is connected to the outside through the nozzle hole 19 while being connected to the supply hose 4. Adhesive Ad is ejected from the nozzle hole 19 by opening the valve body 20 in the holding chamber 18 through the nozzle hole 19. The valve body 20 is connected to a piston 22 via a connecting rod 21, and the piston 22 is inserted into a cylinder 23 formed in the gun body 15 so as to be able to reciprocate. A return spring 24 that urges the piston 22 in a direction to close the nozzle hole 19 is attached to the cylinder 23. The holding chamber 18 and the cylinder 23 are partitioned by a partition wall 25, and an air chamber 28 is formed in a region surrounded by the partition wall 25, the piston 22 and the cylinder 23. The air chamber 28 is supplied with compressed air and stopped by the drive unit 16. When compressed air is supplied to the air chamber 28, the piston 22 moves against the elastic force of the return spring 24 and the valve body 20 is lifted in a direction to open the nozzle hole 19. On the other hand, when the compressed air is discharged from the air chamber 28, the piston 22 is pushed down by the elastic force of the return spring 24, and the valve body 20 closes the injection hole 19.

  The drive unit 16 has a three-port electromagnetic valve 30, and the port a of the electromagnetic valve 30 is connected to the air chamber 28 via the connection path 31, and the port b is connected to the pressure source 33 via the air supply path 32. The ports c are connected to the exhaust path 34, respectively. An operation signal S for causing the coating gun 3 to perform an injection operation is supplied to the electromagnetic valve 30 from the control circuit 13 of the control unit 7. When the operation signal S is obtained, the solenoid valve 30 opens the port a and the port b and supplies the compressed air to the air chamber 28. As a result, the adhesive Ad is sprayed from the coating gun 3. On the other hand, when the supply of the operation signal S to the electromagnetic valve 30 is stopped, the electromagnetic valve 30 opens the port a and the port c and discharges the compressed air from the air chamber 28. Thereby, the injection of the adhesive Ad from the coating gun 3 is stopped. Accordingly, by examining the state of the operation signal S, it is possible to detect the presence or absence of an injection operation for the application gun 3 to inject the adhesive Ad.

  When the adhesive Ad is sprayed from the application gun 3, the supply pressure of the adhesive Ad (strictly, the pressure of an accumulator (not shown) provided downstream of the reciprocating pump 10) decreases. Therefore, the control unit 7 provided in the supply unit 2 switches the switching valve (not on the compressor 12) so that the reciprocating pump 10 strokes when the supply pressure is reduced by a predetermined amount due to the injection of the adhesive Ad from the coating gun 3. (Shown) is operated to keep the supply pressure within the sprayable range. The predetermined amount is set to a value on the lower limit side of the injectable range. Since the supply pressure is maintained within the sprayable range by such an efficient operation of the reciprocating pump 10, the adhesive application device 1 can stably apply the adhesive Ad.

  The adhesive application device 1 is provided with an abnormality detection device 40 for detecting the presence or absence of the abnormality. The abnormality detection device 40 includes a calculation unit 41 that performs various types of information processing for determining whether there is an abnormality in the adhesive application device 1, and a warning display unit 42 that notifies the occurrence of the abnormality based on the processing result of the calculation unit 41. I have. A computer is provided as the calculation unit 41, and a display device capable of displaying various characters and the like is provided as the warning display unit 42. A signal from the proximity sensor 43 that detects the stroke of the reciprocating pump 10 and an operation signal S supplied to the coating gun 3 are input to the calculation unit 41.

  Here, the configuration of the reciprocating pump 10 will be described with reference to FIG. 2 as a premise for explaining the installation form of the proximity sensor 43. FIG. 2 is a longitudinal sectional view showing a main part of the reciprocating pump 10. The reciprocating pump 10 includes a plunger 51, a housing 53 in which a cylinder 52 into which the plunger 51 can be reciprocated is formed, a drive shaft 54 extending from the plunger 51 so as to protrude from the housing 53, and a drive And a drive mechanism 55 for driving the shaft 54.

  The opening of the cylinder 52 is closed by a cap 56, and a pressurizing chamber 57 is formed in a region surrounded by the cap 56 and the plunger 51. A suction port 58 and a discharge port 59 that open to the pressurizing chamber 57 are formed in the housing 53. The adhesive Ad is guided from the holding portion 5 of the supply unit 2 to the suction port 58. Note that a one-way valve 60 that restricts the flow in the suction port 58 in one direction indicated by an arrow is provided in order to prevent back flow of the adhesive Ad during pressurization by the plunger 51.

  The drive mechanism 55 is configured as a piston engine using compressed air from the compressor 12 (FIG. 1) as a working fluid. The drive mechanism 55 includes a cylinder body 63 in which a cylinder 62 into which the piston 61 is reciprocally inserted is formed, and a control valve 64 mounted along the inner peripheral surface of the cylinder 62. The piston 61 is fixed to the end of the drive shaft 54. The upper and lower openings of the cylinder 62 are closed by two closing members 65 arranged so as to sandwich the piston 61. Thereby, two pressure chambers 66 and 67 partitioned by the piston 61 are formed in the cylinder 62.

  The control valve 64 has five ports a to e, and the port a is connected to the compressor 12 (FIG. 1). The port d opens to the first pressure chamber 66, and the port e opens to the second pressure chamber 67. Each of the ports a to e is opened at a predetermined position of a cylindrical common path 68 extending in parallel with the drive shaft 54. A spool 69 extending in a shaft shape is inserted into the common path 68 so as to be capable of reciprocating.

  A pair of large-diameter portions 69a provided on the spool 69 have diameters that fit together so that the common path 68 can be closed, and the distance between them and the axial dimensions thereof are ports a, d, It is set to have a predetermined positional relationship with each opening position of e. Therefore, when the spool 69 moves in the vertical direction in FIG. 2, the port a and the port d are connected via the common path 68, and the port e and the port c are connected via the common path 68. The first state and the second state in which the port a and the port e are connected via the common path 68 and the port d and the port b are connected via the common path 68 are switched.

  In the first state, the compressed air produced by the compressor 12 is guided to the first pressure chamber 66 through the port a and the port d, and the air in the second pressure chamber 67 passes through the port e and the port c. Discharged outside. As a result, the plunger 51 is pushed downward in FIG. 2 via the drive shaft 54, so that the adhesive Ad in the pressurizing chamber 57 is compressed and discharged from the discharge port 59. On the other hand, in the second state, the compressed air is guided to the second pressure chamber 67 via the ports a and e, and the air in the first pressure chamber 66 is discharged to the outside via the ports d and b. Is done. As a result, the plunger 51 is pulled upward in FIG. 2 via the drive shaft 54 and the pressure in the pressurizing chamber 57 is lowered, so that the adhesive Ad held in the holding portion 5 is connected to the connection path 11 and the suction port 58. Through the pressure chamber 57.

  The spool 69 is moved by a moving mechanism 70 interposed between the drive shaft 54 and the spool 69. The moving mechanism 70 is fixed to the lower end of the spool 69 and extends coaxially with the spool 69, a pair of permanent magnets 72 and 73 fixed to the moving rod 71 at a predetermined interval, and one end thereof A fork member 74 is provided that is fixed to the drive shaft 54 and has the other end divided into two forks, and a fork member 74 disposed so that the movable rod 71 is sandwiched in a non-contact state at the fork part 74a. A permanent magnet 75 is embedded in the forked portion 74 a of the fork member 74.

  The polarities of the permanent magnets 72, 73, and 75 are set so that the permanent magnet 75 and the permanent magnet 72 of the fork member 74 are attracted to each other, and the permanent magnet 75 and the permanent magnet 73 are attracted to each other. ing. Accordingly, when the plunger 51 reaches the top dead center and the fork member 74 is located at the first position P1 indicated by the imaginary line, the moving rod 71 pulls the spool 69 by the attractive force between the permanent magnet 75 and the permanent magnet 72. 2 is moved downward. As a result, the control valve 64 is switched to the first state described above, and the air in the second pressure chamber 67 is discharged while the compressed air is guided to the first pressure chamber 66. For this reason, the plunger 51 strokes from the top dead center toward the bottom dead center. Thereafter, when the plunger 51 reaches the bottom dead center and the fork member 74 is located at the second position P2 indicated by an imaginary line, the moving rod 71 pulls the spool 69 by the attractive force between the permanent magnet 75 and the permanent magnet 73. 2 is moved above. As a result, the control valve 64 is switched to the second state described above, and the air in the first pressure chamber 66 is discharged while the compressed air is guided to the second pressure chamber 67. For this reason, the plunger 51 strokes from the bottom dead center toward the top dead center.

  Thus, since the spool 69 operates in conjunction with the plunger 51 in the reciprocating pump 10, the stroke of the reciprocating pump 10 can be detected by detecting the operation of the spool 69. In this embodiment, since the upper end 69 b of the spool 69 is exposed to the outside of the housing 53, the operation can be observed. Therefore, in order to detect the stroke of the reciprocating pump 10, the proximity sensor 43 is installed in the reciprocating pump 10 via the bracket 78 with its tip end opposed to the end 69 b of the spool 69. The bracket 78 is attached to a predetermined stationary part of the reciprocating pump 10. In this embodiment, the end portion 69b of the spool 69 corresponds to the movable portion according to the present invention. Since the proximity sensor 43 detects the operation of the end 69b of the spool 69 that is easily accessible, a space for installing the proximity sensor 43 is secured, or the reciprocating pump 10 is modified to provide the proximity sensor 43. There is no need to do. Therefore, the stroke of the reciprocating pump 10 can be reliably detected with a simple configuration and without much effort.

  FIG. 3 is a block diagram illustrating the function of the calculation unit 41 of the abnormality detection device 40 shown in FIG. The calculation unit 41 detects the operation signal S supplied to the electromagnetic valve 30 by the operation signal detection unit 81 and sends the detection result to the counting unit 82. The counting unit 82 includes a processing unit 83 and a storage unit 84, and the processing unit 83 counts detection results sent from the operation signal detection unit 81. The processing unit 83 reads the variable C for each count, increments the value of the read variable C by one, substitutes it into the variable C, and stores it in the storage unit 84.

  In addition, the calculation unit 41 receives the detection signal Sa that detects the stroke of the reciprocating pump 10 from the proximity sensor 43 by the management unit 85. Every time the management unit 85 receives the detection signal Sa, the management unit 85 reads the variable C from the storage unit 84 and resets it. That is, 0 is substituted for variable C. Thereby, by referring to the value (count value) of the variable C stored in the storage unit 84, it is possible to grasp the number of times of injection of the adhesive by the application gun 3 per stroke of the reciprocating pump 10.

  Therefore, the calculation unit 41 causes the abnormality determination unit 86 to refer to the value of the variable C. The abnormality determination unit 86 determines that the value is abnormal when the value of the variable C exceeds the reference value, and determines that the value is normal when the value is equal to or less than the reference value. When the abnormality determination unit 86 determines that there is an abnormality, the abnormality occurrence signal Sc is sent to the warning display unit 42. The warning display unit 42 performs a predetermined warning display when the abnormality occurrence signal Sc is received.

  The reference value used for abnormality determination by the abnormality determination unit 86 is determined based on the following concept. As described above, the reciprocating pump 10 operates when the supply pressure is reduced by a predetermined amount due to the injection of the adhesive by the coating gun 3. And the supply pressure of an adhesive agent falls with the increase in the frequency | count of the injection. Therefore, for example, if the adhesive pressure increases or the malfunction of the reciprocating pump 10 occurs due to deterioration of the pump itself, the response to the pressure reduction of the supply pressure deteriorates. The number of times the adhesive is sprayed by the application gun 3 per stroke of the stroke increases from the normal time. In other words, when a malfunction occurs in the reciprocating pump 10, the interval at which the reciprocating pump 10 strokes is longer than normal, and the number of adhesive injections between strokes is greater than normal.

  FIG. 4 shows an example of the correspondence relationship between the adhesive injection operation and the stroke, when normal and when abnormal. The upper part of FIG. 4 shows a normal time, and the lower part shows an abnormal time. The correspondence shown in FIG. 4 is that two coating guns 3 are attached to the adhesive coating device 1, one coating gun 3 is used for seam coating of a packaging box, and the other coating gun 3 is used as a side of the packaging box. The present invention relates to an application system in which the spray timing of the adhesive is shifted for application. In this system at normal time, it has been found through investigation that the number of adhesive injection operations is about 32 to 34 times per stroke of the reciprocating pump 10. Therefore, 36 times is set as a reference value for abnormality determination from the viewpoint of preventing erroneous determination by taking into account variations in the number of injections. Therefore, in this system, if the detection signal Sa can be detected within the range A that is equal to or less than the reference value, it can be determined that the system is normal. In the normal state of FIG. 4, the detection signal Sa is detected with a total of 34 adhesive injection operations by the seam and side application guns 3, and thus the value of the variable C described above is 34. Yes, judged to be normal. On the other hand, in the case of the abnormality in FIG. 4, the detection signal Sa is detected with the number of injections of 38. That is, the stroke of the reciprocating pump 10 is delayed as compared with the normal time. In this case, since the value of the variable C described above is 38 and exceeds the reference value 36, it is determined to be abnormal.

  As described above, the reference value indicates the correspondence between the injection operation by the application gun 3 and the stroke of the reciprocating pump 10 in a normal state, that is, the correspondence between the number of injections by the injection gun 3 and the number of strokes of the reciprocating pump 10. Survey is set based on the survey results. However, since the correspondence relationship between the spraying operation by the application gun 3 and the stroke of the reciprocating pump 10 can vary depending on the number of application guns 3 included in the system, the length of the supply hose 4 and individual differences of each component, etc. The reference value should be set for each system. The value of the reference value can be set as appropriate. For example, by setting the reference value to the strict side (smaller side), it is possible to determine that the sign before the reciprocating pump 10 is seriously malfunctioning is abnormal. As a result, a serious malfunction that can cause the reciprocating pump 10 to become inoperable can be prevented in advance, so that the occurrence of malfunctions caused by such malfunction can be minimized.

  In the present embodiment, the motion detection unit 81 shown in FIG. 3 is an injection detection unit according to the present invention, the proximity sensor 43 is a stroke detection unit according to the present invention, and an abnormality determination unit 86 is an abnormality determination unit according to the present invention. The counting unit 82 corresponds to the counting unit according to the present invention, and the management unit 85 corresponds to the counting management unit according to the present invention. However, the present invention is not limited to the above embodiments, and can be implemented in various forms within the scope of the gist of the present invention. The method for judging abnormality is not limited to the method of the above embodiment. In the above embodiment, the abnormality is determined based on the number of injection operations per stroke of the reciprocating pump 10, but the condition for the management unit 85 to reset is changed to detecting a plurality of detection signals Sa. For example, it is possible to determine abnormality based on the number of injection operations per multiple strokes.

  Further, the correspondence relationship between the stroke of the reciprocating pump, which is a criterion for abnormality determination, and the injection operation of the injection means is not limited to the correspondence relationship of these numbers. For example, it is also possible to determine an abnormality based on the above-described correspondence relationship with respect to the time until the reciprocating pump operates from a specific injection operation of the injection means. In the above embodiment, the operation signal S supplied to the application gun 3 is detected as an injection operation for the application gun 3 to inject the adhesive. For example, the connection rod 21 and the piston 22 of the application gun 3 are detected. By providing detection means such as a lift sensor, it is also possible to detect as an injection operation that the application gun 3 has actually injected.

DESCRIPTION OF SYMBOLS 1 Adhesive application apparatus 2 Supply unit (adhesive supply means)
3 Application gun (spraying means)
10 reciprocating pump 40 abnormality detection device 43 proximity sensor (stroke detection means)
51 Plunger 52 Cylinder 53 Housing 81 Injection detection means 69b End of spool (movable part)
82 Counting unit (counting means)
85 management unit (counting management means)
86 Abnormality determination unit (abnormality determination means)
Ad hot melt adhesive

Claims (4)

A jetting means capable of jetting hot melt adhesive; and an adhesive supply means for feeding the adhesive to the jetting means using a reciprocating pump, and jetting the adhesive to the jetting means. Applied to an adhesive application device that strokes the reciprocating pump when the adhesive supply pressure is reduced by a predetermined amount;
Injection detection means for detecting an injection operation for the injection means to inject the adhesive;
Stroke detecting means for detecting a stroke of the reciprocating pump;
An abnormality determination unit that determines an abnormality of the adhesive application device based on a correspondence relationship between the injection operation detected by the injection detection unit and the stroke detected by the stroke detection unit;
An abnormality detection device characterized by comprising:   2. The abnormality detection device according to claim 1, wherein the abnormality determination unit determines the abnormality by acquiring, as the correspondence relationship, the number of injection operations per predetermined number of strokes. Counting means for counting the number of injection operations of the injection means detected by the injection detection means, and storing the number of times as a count value;
Count management means for resetting the count value stored in the counting means when the stroke detecting means detects the stroke a predetermined number of times, and
The abnormality determination means acquires the number of times of the injection operation per predetermined number of strokes based on the count value stored by the counting means, and determines that the abnormality is present when the count value exceeds a reference value. The abnormality detection device according to claim 2. The reciprocating pump includes a housing formed with a cylinder into which a plunger is inserted in a reciprocating manner, and a movable portion that is provided in a state exposed to the outside of the housing and interlocks with the operation of the plunger. ,
The abnormality detection device according to any one of claims 1 to 3, wherein a proximity sensor capable of detecting an operation of the movable part in a non-contact state with the movable part is provided as the stroke detection means.

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