TWI682711B - Foreign body detection mechanism of electric shear - Google Patents

Abstract

Provided is a foreign body detection mechanism of an electric shear. The foreign body detection mechanism of an electric shear can prevent the wire from being erroneously cut even if a dedicated sensor or circuit is not provided.

The electric shear 10 includes a blade portion 18 and 19 linked to the rotation of the motor 12, and a foreign object detection mechanism for detecting the electric shear 10 with a foreign object inserted, which includes a foreign object detection means for detecting the foreign object caught in the blade portion 18 and 19 ; The foreign object detection by the foreign object detection means is performed according to the torque information of the motor 12.

Description

Foreign body detection mechanism of electric shear

The invention relates to an electric shear used for opening and closing a blade portion by electric power.

Electric shears are used for pruning trees, etc. The electric shears are made to open and close a pair of blades by the driving force of a motor, so that cutting objects such as branches can be cut.

On the other hand, in fruit tree cultivation and the like, an iron wire (metal wire) is provided on a pillar to form a fruit tree scaffold. In such fruit tree cultivation using fruit tree scaffolding for pruning work, the operator may cut the wire by mistake. If the wire is cut, the wire may be redrawn. In addition, even if the iron wire is not cut, the blade part of the electric shear may collapse due to the insertion of the hard iron wire. When the electric shear continues to be used in a state where the blade collapses, the blade eventually becomes damaged or the object cannot be cut normally.

As a technology related to this problem, for example, Patent Document 1 discloses an electric shear. The electric shear is provided with a dedicated conductive sensor and a dedicated circuit on the blade. If an electrical contact is detected on the blade, it is made Interrupt the closing of the blade. The technology described in this Patent Document 1 uses special gloves to prevent injury, but if this technology is applied, by detecting the metal wire at the blade portion, it is possible to prevent the wire from being erroneously cut.

【Advanced Patent Literature】 【Patent Literature】

[Patent Document 1] French Patent No. 2838998

However, the technique described in Patent Document 1 requires a dedicated conductive sensor and a dedicated circuit to be provided in the blade portion, so there is a problem that the manufacturing cost becomes expensive. In addition, it has a problem that the machine becomes larger, the blade becomes thicker and the cutting performance is reduced, the maintenance of the blade becomes difficult, and there is a false detection of the sensor when the sap or moisture adheres to the blade. Problems of possibility etc.

Therefore, the object of the present invention is to provide a foreign object detection mechanism of an electric shear. The foreign object detection mechanism of the electric shear does not provide a dedicated sensor or circuit, and can also prevent erroneous cutting of the wire.

The present invention was developed to solve the above-mentioned problems and has the following features.

For example, the invention of claim 1 in the patent scope is an electric shear that includes a blade that is linked to the rotation of the motor, and a foreign object detection mechanism that detects an electric shear that is caught in a foreign object. Foreign object detection means; the foreign object detection by the foreign object detection means is performed based on the torque information of the motor: as the torque information of the motor, the rate of change of the torque of the motor is used; if the torque of the motor changes If the rate is less than the predetermined threshold, it is judged that the branch is cut, and if the rate of change of the torque of the motor is above the predetermined threshold, it is judged that foreign objects are caught.

For example, the invention of claim 2 is characterized by not only the feature points of the invention as claimed in item 1, but also the feature: the foreign object detection means is based on the closing angle of the blade and is preset from The threshold value data selects the threshold value and compares the threshold value with the torque information of the motor to perform foreign object detection.

For example, the invention of the third patent application is characterized by not only the feature points of the invention of the first patent application, but also that the torque information of the motor is based on the current value, voltage value or speed of the motor. A speculation.

For example, the invention of the fourth patent application is characterized by not only the feature points of the invention of any one of the first to third patent applications, but also the feature: the detection of foreign objects by the foreign object detection means is to It is judged that the blade portion is closed to a predetermined angle is invalid, and becomes effective after it is judged that the blade portion is closed to a predetermined angle.

For example, the invention of claim 5 is characterized by not only the feature points of the invention as described in any of items 1 to 3 of the patent application, but also features: a foreign object detection mode that performs detection of foreign objects, and Continuous execution mode that does not perform detection of foreign objects; includes switching means to switch between these two modes.

For example, the invention of the sixth patent application is characterized by not only the feature points of the invention of any one of the first to third patent applications, but also the feature: when the foreign object detection means detects a foreign object, The motor stops.

For example, the invention of the seventh patent application is characterized by not only the feature points of the invention of any one of the first to third patent applications, but also the feature: when the foreign object detection means detects a foreign object, The motor reverses.

If the invention of the 8th patent application is characterized by not only The feature point of the invention of any one of the items 1 to 3 of the patent application scope, and the feature is: when the foreign object detection means detects a foreign object, the user is notified of the abnormality.

For example, the invention of claim 9 is characterized by not only the feature points of the invention as described in any of items 1 to 3 of the patent application, but also: when the foreign object detection means detects a foreign object, The power path is physically cut so that the power of the motor is not transmitted to the blade.

For example, the invention of claim 10 is characterized by not only the feature points of the invention as described in any of items 1 to 3 of the patent application, but also features: including adjustment of the torque of the motor transmitted to the blade Clutch mechanism; when the foreign object detection means detects a foreign object, the clutch mechanism becomes effective.

The invention as claimed in item 1 of the patent application scope is as described above, and includes foreign object detection means for detecting foreign objects caught in the blade portion; foreign object detection by the foreign object detection means is performed according to the torque information of the motor . According to this configuration, without the provision of a dedicated sensor or circuit, the object to be cut, such as a tree, can be surely cut, and foreign objects can be detected when the thin and hard wire or the like is to be cut.

For example, when comparing an object to be cut such as a tree with an iron wire, the object to be cut is relatively thick and soft, and the iron wire is thin and hard. Therefore, when the torsion force generated when the blade part is to be closed is different from the usual value, foreign objects can be detected because of the possibility of cutting the wire.

In addition, in the detection of foreign objects, the torque value of the motor can also be used directly, or the slope of the torque value of the motor (variation of torque in a fixed time) can also be used.

In addition, if the invention of the first item of patent application is as shown above, As the torque information of the motor, the rate of change of the torque of the motor is used. According to this configuration, since it is possible to grasp the rise of the torque when starting to cut off foreign objects, it is possible to immediately detect the insertion of foreign objects.

That is, since the object to be cut, such as a tree, is thick and soft, when cutting the object to be cut, after the blade part penetrates the epidermis, the torsional torque value near the center of the object to be cut is cut It becomes the largest, and then, as the blade portion gradually closes, the torque value gradually decreases. That is, when the object to be cut is cut, the torsional force tends to increase slowly.

On the other hand, since the foreign material such as an iron wire is relatively thin and hard, when cutting the foreign material such as an iron wire, the torsion force increases rapidly immediately after the iron wire comes into contact with the blade portion.

If the slope of the torque value using the motor is used in this way, because the rise of the torque when starting to cut off foreign objects can be grasped, the inclusion of foreign objects can be detected immediately.

Also, if the invention of the first item of the patent application scope is as described above, because if the rate of change of the torque of the motor is less than the predetermined threshold, the branch is judged to be cut, and if the rate of change of the torque of the motor is the predetermined Above the threshold, it is judged that a foreign object is caught, so it is possible to perform a control to judge that the branch is cut when the torque rise is slow, and when the rapid rise is caused.

In addition, if the invention of the second item of the patent application scope is as described above, the foreign object detection means selects the threshold value from the preset threshold data according to the closing angle of the blade, and compares the threshold The limit value and the torque information of the motor are used to detect foreign objects. According to this configuration, the thick branch and the thin wire can be distinguished from the angle of the blade portion, and the thin branch and the wire can be distinguished from the torque of the motor, so foreign objects can be reliably detected.

For example, the threshold value after the blade portion is closed to a predetermined angle may be set to be lower than the threshold value before the blade portion is closed to a predetermined angle (or, it may be made as a threshold value before the blade portion is closed to a predetermined angle) It is not set, and the threshold is not checked if no threshold is set). In this way, if the torque value of the motor rises before the blade is closed to a predetermined angle, because there is a high possibility of cutting thick trees, it is not detected as a foreign object. On the other hand, after the blade is closed to a predetermined angle When the torque value of the motor rises, there is a high possibility of cutting relatively thin and hard foreign objects such as wire, so it can be detected as a foreign object.

In addition, as the invention of claim 3 of the patent application is as described above, the torque information of the motor is estimated based on any one of the current value, voltage value, or rotation speed of the motor. According to this configuration, without using a special sensor, etc., it is also possible to detect the increase of the torque, that is, the inclusion of foreign objects.

In addition, if the invention of claim 4 of the patent application is as described above, the detection of the foreign object by the foreign object detection means is invalid to judge that the blade is closed to a predetermined angle, and it is determined that the blade is closed to the predetermined The angle becomes effective afterwards. According to this configuration, since the blade portion is closed to a predetermined angle, even if the torque value of the motor increases, foreign objects are not detected. Therefore, erroneous detection of foreign objects does not occur when cutting objects such as trees. In addition, when the torque value of the motor rises after the blade is closed to a predetermined angle, it is possible to detect relatively thin and hard foreign objects such as wire, so it can be detected as a foreign object.

Also, as the invention of claim 5 in the patent application scope is as described above, it has a foreign object detection mode that performs foreign object detection, and a continuous execution mode that does not perform foreign object detection; including the two modes for switching Switching means. According to this configuration, it is possible to switch to continuous execution when cutting thin and hard branches, for example Line mode, so you can avoid the problem of misdetection of foreign objects.

Moreover, as the invention of claim 6 of the patent application scope is shown above, when the foreign object detection means detects a foreign object, the motor is stopped. According to this configuration, since the cutting operation is not further performed when a foreign object is detected, it is possible to avoid the problem of cutting the wire or cutting the blade.

Also, as the invention of claim 7 of the patent application scope is as described above, when the foreign object detection detects a foreign object, the motor is reversed. According to this configuration, not only will the cutting operation not be further performed when a foreign object is detected, but also the foreign object caught in the blade portion will be released, so that the problem of cutting the wire or the blade collapse of the blade portion can be avoided.

In addition, if the invention of claim 8 of the patent application is as described above, when the foreign object detection means detects a foreign object, the user is notified of the abnormality. According to this configuration, the user can immediately recognize and deal with foreign object detection. For example, in the case of using an electric shear that does not stop the cutting action when a foreign object is detected, the user himself can choose whether to continue the cutting action.

Moreover, as the invention of claim 9 of the patent application scope is as described above, when the foreign object detection means detects a foreign object, the power path is physically cut so that the power of the motor will not be transmitted to the blade. According to this configuration, since the cutting operation is not further performed when a foreign object is detected, it is possible to avoid the problem of cutting the wire or cutting the blade.

Also, as the invention of claim 10 in the patent application scope is shown above, it includes a clutch mechanism that adjusts the torque of the motor transmitted to the blade portion; when the foreign object detection means detects a foreign object, the clutch mechanism becomes effective. According to this configuration, because the upper limit of the torque is reduced when a foreign object is detected, it is not There will be a torque that cuts the wire or causes a blade collapse at the blade.

10‧‧‧Electric scissors

11‧‧‧Cable connection

12‧‧‧Motor (power source)

13‧‧‧Ball screw mechanism

14‧‧‧Reduction mechanism

15‧‧‧Link mechanism

15a‧‧‧Drive shaft

15b‧‧‧1st link

15c‧‧‧ 2nd link

16‧‧‧Supporting member

16a‧‧‧Guide groove

17‧‧‧Housing

17a‧‧‧Link cover part

17b‧‧‧Operation member protection department

17c‧‧‧handle

17d‧‧‧ Rear

17e‧‧‧ Rear face

18‧‧‧1st blade

18a‧‧‧Cut off

18b‧‧‧Root

18c‧‧‧Connecting shaft

19‧‧‧ 2nd blade

19a‧‧‧Cut off

19b‧‧‧Root

19c‧‧‧Connecting shaft

20‧‧‧ Blade shaft

22‧‧‧operating member

22a‧‧‧axis

22b‧‧‧First operation section

22c‧‧‧roll

22d‧‧‧ 2nd operation section

23‧‧‧swing member

23a‧‧‧swing axis

23b‧‧‧ Pushing Department

24‧‧‧Micro switch

24a‧‧‧Contact Department

25‧‧‧Sensor

26‧‧‧Rotation Detection Department

30‧‧‧cable

31‧‧‧Core

32‧‧‧Connecting terminal

33‧‧‧Division

34A~34N‧‧‧ Mother pin

35A~35D‧‧‧core wire

40‧‧‧Power supply device

41‧‧‧horn

42‧‧‧LED

43‧‧‧Cable connection

44‧‧‧Secondary battery

100‧‧‧Control board (foreign object detection method)

110‧‧‧Rotation judgment unit

120‧‧‧Current Detection Department

130‧‧‧Current Change Calculation Department

140‧‧‧ Current Judgment Department

Figure 1 is the right side view of the electric shear.

Figure 2 is a right side view showing the internal structure of the electric shear.

Figure 3 is a left side view showing the internal structure of the electric shear.

Fig. 4 is an explanatory diagram showing the cutting operation, Fig. 4 (a) is a diagram showing a state where the blade is opened, and Fig. 4 (b) is a diagram showing a state where the blade is closed.

Fig. 5 is an explanatory diagram showing the operation of the operating member, Fig. 5 (a) is a diagram of a state where the operating member is not operated, and Fig. 5 (b) is a diagram of a state where the first operating part has been operated, Fig. 5 (c) is a view of the state in which the second operation unit has been operated.

FIG. 6 is a block diagram showing the structure of the foreign object detection mechanism of the electric shear.

The seventh series is a flowchart showing the cutting operation of the electric shear.

Fig. 8 is a waveform diagram showing the change in current value when the object or foreign object to be cut is cut.

Fig. 9 (a) is a cross-sectional view of the connection terminal of the cable, and Fig. 9 (b) is a cross-sectional view of the connection terminal of the cable according to a modification.

Figure 10 is a front view of the cable connection terminals.

Fig. 11 is a flowchart showing the cutting operation of the electric shear according to the modification.

With reference to the drawings, an embodiment of the present invention will be described.

The electric shears 10 of the present embodiment are used, for example, for pruning trees, etc., and a pair of blades 18, 19 are opened and closed by a driving force of a motor 12 as a power source, and cutting objects such as branches are cut.

This electric shear 10 is shown in FIGS. 1 to 3 and includes: a housing 17; a cable connection portion 11 provided at the rear end of the housing 17; a motor 12; a ball screw mechanism 13 used to connect the motor 12 The rotary motion of the machine is converted into a linear motion; the support member 16 guides the linear motion of the ball screw mechanism 13; the link mechanism 15 is used to convert the linear motion of the ball screw mechanism 13 into the opening and closing of the two blades 18, 19 Action; the first blade portion 18 and the second blade portion 19 are operated by the link mechanism 15; the operating member 22 is provided as an operating portion for controlling the motor 12; the swing member 23 is used to track the operating member 22 The micro switch 24 is used to push the contact by the swing member 23; the sensor 25 is used to detect the rotation angle of the operation member 22; and the rotation detection unit 26 is used to detect the rotation of the motor 12.

The housing 17 is not specifically shown, and is composed of two divided pieces. The operating mechanism is housed inside and covers almost the entire machine. In addition, the housing 17 includes: a link cover portion 17a, which covers the link mechanism 15; an operating member protection portion 17b, which forms a ring so as to cover the periphery of the operating member 22; and a handle portion 17c, which can be gripped by the user It is formed in the way of entering; and the rear end portion 17d is provided at the rear portion of the handle portion 17c.

The link cover portion 17a accommodates the link mechanism 15 provided at the front end portion of the housing 17, and protrudes the first blade portion 18 and the second blade portion 19 from the front end portion.

The operation member protection portion 17b is provided below the rear portion of the link cover portion 17a, and is provided at the boundary (between) of the link cover portion 17a and the handle portion 17c. The operation member protection portion 17b is formed in a ring shape, and when the user grips the handle portion 17c, it is arranged to hook the index finger into the ring-shaped operation member protection portion 17b. On the inner side of the operating member protection portion 17b, the operating member 22 is exposed to be operable Make. The details will be described later. The first operating portion 22b (trigger) of the operating member 22 is exposed to be operable at the front (handle portion 17c side), and the second operating portion 22d of the operating member 22 is exposed at the front (side of the link cover portion 17a) Into operable.

The handle portion 17c is formed to be thinner than the link cover portion 17a and slightly thinner than the rear end portion 17d, so that the user can easily grasp it. A ball screw mechanism 13 is built into this handle portion 17c.

The rear end portion 17d accommodates the motor 12 provided at the rear end of the housing 17, and the cable connection portion 11 is provided at the rear end surface 17e.

The cable connection portion 11 is a portion for connecting the cable 30 and includes a terminal for connecting a power line or a signal line. The cable 30 connected to the cable connection portion 11 is connected to the power supply device 40 (see FIG. 6 ). The power switch is installed in the power supply device 40 or the cable 30, and by switching on the power switch, electric power is supplied from the power supply device 40 to the electric scissors 10 via the cable 30.

The motor 12 is a power source that causes the first blade portion 18 and the second blade portion 19 to perform the closing operation, and operates by the electric power supplied from the power supply device 40. The output shaft of the motor 12 is connected to a ball screw mechanism 13 described later. In addition, the speed reduction mechanism 14 or the like may be provided between the output shaft of the motor 12 and the ball screw mechanism 13, or the output shaft of the motor 12 may be directly connected to the ball screw mechanism 13.

The ball screw mechanism 13 converts the rotation motion of the motor 12 into a linear motion motion. The ball screw mechanism 13 is not specifically shown, and includes: a screw shaft that receives the rotational force of the motor 12 to rotate; and a nut portion that engages with the screw groove of the screw shaft. Accordingly, when the screw shaft is rotationally driven by the driving force of the motor 12, the nut portion moves linearly along the screw shaft. At this nut portion, a drive shaft 15a of a link mechanism 15 described later is connected, and this drive shaft 15a is It is formed so as to linearly move back and forth integrally with the nut portion.

The support member 16 is used to guide the linear movement of the ball screw mechanism 13. A guide groove 16a extending in the guide direction is provided on the support member 16, and the drive shaft 15a of the link mechanism 15 is engaged with the guide groove 16a. Therefore, the nut portion and the drive shaft 15a move along the extending direction of the guide groove 16a.

The link mechanism 15 converts the linear motion of the drive shaft 15a into opening and closing operations of the first blade portion 18 and the second blade portion 19. This link mechanism 15 includes a first link 15b and a second link 15c that are rotatably connected by a drive shaft 15a. The first link 15b has one end connected to the drive shaft 15a, and the other end connected to the first blade portion 18 via a connection shaft 18c. In addition, the second link 15c is connected at one end to the drive shaft 15a, and at the other end to the second blade portion 19 via the connection shaft 19c.

The first blade portion 18 and the second blade portion 19 are supported so as to be rotatable about the blade shaft 20 as a fulcrum, and are combined to branch on the blade shaft 20. The first blade portion 18 is a cutting portion 18a formed with a blade at the tip end side of the blade shaft 20, and the root portion 18b closer to the root side than the blade shaft 20 is rotatably connected to the first link 15b via a connecting shaft 18c. Similarly, the second blade portion 19 is a cutting portion 19a formed on the tip side of the blade shaft 20, and the root portion 19b on the root side of the blade shaft 20 is connected to the second link 15c via a connecting shaft 19c. Turnable.

The link mechanism 15, the first blade portion 18, and the second blade portion 19 described above are operated by the linear motion of the ball screw mechanism 13 as shown in FIG.

Specifically, when the drive shaft 15a moves in the direction approaching the blade shaft 20, the first link 15b and the second link 15c move in the opening direction. As a result, the root portions 18b, 19b of the first blade portion 18 and the second blade portion 19 are displaced away from each other, and the cutting portions 18a, 19a of the first blade portion 18 and the second blade portion 19 are Turn in the direction of closing each other to perform the cutting operation.

On the other hand, when the drive shaft 15a moves away from the blade shaft 20, the first link 15b and the second link 15c move in the closing direction. By this, the root portions 18b, 19b of the first blade portion 18 and the second blade portion 19 are displaced in the direction of approaching each other, and the cutting portions 18a, 19a of the first blade portion 18 and the second blade portion 19 are in the direction of opening to each other Turn.

The operation member 22 of this embodiment is attached so as to be rotatable about the shaft 22a. The operating member 22 has a substantially L-shape in a side view as shown in FIG. 2 and the like, and includes a first operating portion 22b and a second operating portion 22d that extend in different directions from the position where the shaft 22a is provided. The first operating portion 22b is an operating portion for controlling the operation of the motor 12, and by controlling the operation of the motor 12, an opening (closing) operation by the first blade portion 18 and the second blade portion 19 is performed (controlled). The second operation unit 22d is used to perform auxiliary operations (for example, switching of operation modes). The first operation portion 22b and the second operation portion 22d are arranged to face each other, and are exposed to be operable inside the operation member protection portion 17b. Therefore, when a finger is inserted between the first operation portion 22b and the second operation portion 22d, as shown in FIG. 5(b), when the finger is moved to the rear of the shaft 22a (handle portion 17c side), the first operation can be operated As shown in FIG. 5(c), the portion 22b can operate the second operation portion 22d when the finger is moved forward with respect to the shaft 22a (the link cover portion 17a side). When the first operation portion 22b or the second operation portion 22d is operated, the operation member 22 rotates about the shaft 22a. In this way, when the electric scissors 10 pulls the first operation portion 22b to approach the handle portion 17c, the opening and closing operations of the first blade portion 18 and the second blade portion 19 are performed, and the second operation portion 22d is operated When the push operation is performed away from the handle portion 17c, an auxiliary operation is performed. In addition, the first operation portion 22b and the second operation portion 22d are provided such that Cannot move relative to each other. When the first operation portion 22b is operated, the second operation portion 22d also moves in the same direction as the first operation portion 22b in conjunction with the first operation portion 22b. When the second operating portion 22d is operated, the first operating portion 22b also moves in the same direction as the second operating portion 22d in conjunction with the second operating portion 22d. Therefore, the first operating portion 22b and the second operating portion 22d cannot be operated simultaneously, but are operated separately. When the first operating portion 22b is operated and when the second operating portion 22d is operated, the operating member 22 rotates in a different direction .

In addition, the roller 22c shown in FIG. 4 is provided inside the first operation portion 22b. The roller 22c is used to push the swing member 23 described later.

When the first operating portion 22b of the operating member 22 is operated, the swinging member 23 tracks the rotation of the operating member 22 and swings. The swing member 23 can swing about the swing shaft 23a, and when the operation member 22 rotates, it is forced to swing by the roller 22c. The swinging member 23 includes a pressing portion 23b configured to face a contact portion 24a of a micro switch 24 described later. When the roller 22c is forced to swing, the pressing portion 23b is pushed into the contact portion 24a of the micro switch 24.

The micro switch 24 detects that the first operating portion 22b of the operating member 22 is operated. As described above, when the first operating portion 22b configured as the operating member 22 is operated, the swing member 23 turns the micro switch 24 on, and by detecting whether the micro switch 24 is conducting or not, it can be determined whether the operating member 22 The first operation portion 22b is operated.

The sensor 25 is used to detect the rotation angle of the operating member 22. As the sensor 25, as long as the operator can detect the operation member 22, regardless of the type, for example, a potentiometer connected to the shaft 22a can be used. In the case of using a potentiometer, the operation amount of the operation member 22 can be grasped carefully.

The rotation detection unit 26 is used to detect the rotation of the motor 12 and is composed of, for example, a Hall IC. When the Hall IC is used to configure the rotation detection unit 26, the magnet is mounted on the rotating part of the shaft, wheel, or the like of the motor 12, and the presence or absence of the magnet is detected by the Hall IC, thereby detecting the rotation of the motor 12. The rotation of the motor 12 detected by the rotation detection unit 26 is transmitted to the power supply device 40 via the cable 30 and used.

The operation of the electric shear 10 is controlled by the control device built in the electric shear 10 or the power supply device 40. In the control device, when the first operating portion 22b of the operating member 22 is operated to detect that the micro switch 24 is turned on, the rotation angle of the operating member 22 is detected by the sensor 25. Then, according to the detected angle, the motor 12 is rotated forward, and the two blade portions 18, 19 are operated in the closing direction, and when the first operating portion 22b of the operating member 22 is operated to the limit, the two blade portions 18, 19 become Completely closed. In addition, when the first operating portion 22b is released, the operating member 22 is returned to the initial position by a spring (not shown). When the sensor 25 detects that the operation member 22 returns to the starting position, the sensor 25 transmits a control signal to the control device. The control device that receives this control signal reverses the motor 12 and operates the two blade portions 18 and 19 to the maximum opening angle. Return to the starting position with 12 blades 18,19. At the same time, because the micro switch 24 becomes non-conductive when the operating member 22 returns to the initial position, the two blade portions 18, 19 can be maintained at the maximum opening angle to stop.

As shown in FIG. 6, the power supply device 40 that supplies power to the electric shear 10 described above includes a cable connection portion 43, a secondary battery 44, a control board 100, a speaker 41, and an LED 42.

The cable connection portion 43 is a portion for connecting the cable 30 and includes Includes terminals for connecting power lines or signal lines. That is, the cable connecting portion 43 is used to connect the electric shear 10 and the power supply device 40 using the cable 30.

The secondary battery 44 is used to store the power supplied to the electric scissors 10. The secondary battery 44 is also used to drive the power supply device 40.

The control board 100 is used to control the operation of the electric scissors 10, and has a CPU or a memory and a control circuit. In the present embodiment, the control substrate 100 constitutes a foreign object detection means for detecting foreign objects between the two blade portions 18 and 19. In addition, the control board 100 has various functions in addition to the foreign object detection means, but description of these functions is omitted.

The control board 100 includes the rotation determination unit 110, the current detection unit 120, the current change amount calculation unit 130, and the current determination unit 140 to constitute the above-described foreign object detection means.

The rotation determination unit 110 obtains the rotation signal of the motor 12 transmitted from the rotation detection unit 26 of the electric shear 10, and checks whether the rotation amount of the motor 12 (the number of rotations of the motor 12) reaches a predetermined rotation amount. The rotation of the motor 12 is reset to zero when the two blade portions 18 and 19 are at the starting position, and then, every time the rotation signal of the motor 12 is obtained from the rotation detection portion 26, it is gradually counted up to thereby measure. The rotation determination unit 110 determines that the two blade portions 18 and 19 are closed to a predetermined angle when the rotation amount of the motor 12 reaches a predetermined rotation amount.

The current detection unit 120 detects the current value supplied to the electric shear 10 by measuring the current value supplied to the electric shear 10. The current value measured by the current detection unit 120 is used to calculate the torque value of the motor 12, in other words, to detect foreign objects.

The current variation calculation unit 130 is based on the current detection unit 120 The detected current value calculates the amount of change in the current value within a fixed time (for example, 1ms). From this, the slope of the torque value of the motor 12 within a fixed time is estimated (the amount of change in the torque in a predetermined time, that is, the rate of change of the torque).

The current determination unit 140 obtains information on the rotation amount of the motor 12 from the rotation determination unit 110, and also obtains information on the torque of the motor 12 from the current change amount calculation unit 130 (in this embodiment, the rate of change of the torque). Then, based on the information, determine the possibility of foreign objects being caught. Specifically, after estimating the closing angles of the two blade portions 18 and 19 based on the information obtained from the rotation judging section 110, the current judging section 140 selects a specific clinical position corresponding to the closing angle from the preset threshold data Limit. Then, this specific threshold value is compared with the torque information of the motor 12 obtained from the current change amount calculation unit 130. In addition, when the change amount of the current value calculated by the current change amount calculation unit 130 exceeds this specific threshold value, it is judged that a foreign object is caught, and a predetermined error process is executed.

In addition, the threshold data used for comparison with the torque information of the motor 12 is preset in the machine according to the purpose of use of the electric shear 10 and the like. The threshold value included in the threshold value data is managed in relation to the closing angle of the blade portions 18 and 19 (the amount of rotation of the motor 12). The threshold value is used for switching at least two different threshold values. For example, the threshold A is used in the range where the motor 12 rotates less than 60 turns, and the threshold B is used in the range where the motor 12 rotates more than 60 turns, depending on the closing angle of the blades 18 and 19 (motor 12) The amount of rotation) is used for switching.

In addition, when it is desired that the closing angle of the blades 18 and 19 (the amount of rotation of the motor 12) is within a fixed range and foreign object detection is not performed, the fixed range may also be regarded as "no threshold". For example, instead of setting the threshold value before the blades 18 and 19 are closed to a predetermined angle, only the blades 18 and 19 are set The threshold value after closing to a predetermined angle may be such that the threshold value of the current judgment unit 140 is not checked when the threshold value data is not set. In this way, in the case where the torque value of the motor 12 rises before the blades 18 and 19 are closed to a predetermined angle, the possibility of cutting thick branches is high, so it is detected as not a foreign body. 19 When the torque value of the motor 12 rises after closing to a predetermined angle, it may be detected as a foreign object because of the possibility of cutting off relatively thin and hard foreign objects such as wire.

The speaker 41 is used to output a buzzing sound when the power is turned on, or a buzzing sound when an error is made.

LED42 is used to display the action mode or error display of electric shear 10.

Next, referring to FIG. 7, the cutting operation and the foreign object detection operation of the electric shear 10 will be described.

First, in step S100 shown in FIG. 7, the operation member 22 is operated, and the motor 12 starts driving.

In step S101, the rotation determination unit 110 obtains the rotation amount of the motor 12. Then, it moves to step S102.

In step S102, at regular intervals, the current detection unit 120 measures the current value, and based on the current value, the current variation calculation unit 130 calculates the variation of the current value within a fixed time. Then, it moves to step S103.

In step S103, the current determination unit 140 obtains information on the rotation amount of the motor 12 from the rotation determination unit 110, and estimates the closing angle of the two blade portions 18, 19. Then, according to this closing angle, the threshold value is selected from the preset threshold value data. Also, the torque of the motor 12 is obtained from the current change calculation unit 130 Information (the amount of change in current value within a fixed time). Next, check whether the amount of change in this current value exceeds the threshold. When the amount of change in the current value exceeds the threshold value, it is determined that a foreign object is caught, and the process moves to step S106. On the other hand, when the amount of change in the current value does not exceed the threshold, the process moves to step S104.

When moving to step S104, it is checked whether the two blade parts 18 and 19 are fully closed. If it is detected that the two blade portions 18 and 19 are completely closed, the process moves to step S105. On the other hand, if the two blade portions 18 and 19 are not fully closed, the process returns to step S101.

When the process moves to step S105, the motor 12 is stopped, and the process is ended.

When the process moves to step S106, that is, when it is judged that a foreign object is caught in step S103, predetermined error processing is performed. The error processing of this embodiment is a process of stopping the motor 12 and reversing the motor 12. By performing this process, even when a foreign object such as an iron wire is caught, the blade portions 18 and 19 are opened before the foreign object is cut.

As described above, the foreign object detection mechanism of the electric shear 10 of the present embodiment performs the detection of foreign objects by monitoring the angle information of the blade portions 18 and 19 and the torque information of the motor 12. The structure of this detection is based on the focus shown below.

That is, when the thick branches are cut as shown in FIG. 8, the torque of the motor 12 begins to increase at the timing when the blades 18 and 19 start to close, and the torque of the motor 12 becomes maximum near a predetermined angle (see FIG. The motor rotation amount of X is the waveform near "50"). On the other hand, when cutting foreign objects such as wire, the torque of the motor 12 rapidly increases immediately before the blades 18 and 19 are fully closed, and becomes the maximum value equivalent to X when cutting a thick branch (refer to FIG. 8 The amount of motor rotation in Y (The waveform near "70").

In addition, when the general thin branches are cut as shown by the waveform Z, the timing of the increase in the torque of the motor 12 is near the same amount of motor rotation "70" when the wire is cut, but the torque is not so large.

As shown by the experimental results, even when the thin and hard iron wire is cut and the thin live tree is cut, even if the timing of the torque variation of the motor 12 is the same, the maximum torque is different.

In addition, in the case of cutting a relatively thick and soft live tree and the case of cutting a thin and hard iron wire, even if the maximum value of the torque of the motor 12 is equal, the timing of torque change varies.

The present inventors focused on the difference in the torque value or the variation timing that differs for each cutting object, and created a threshold value for determining the torque of the foreign body in response to the angle switching of the blade portions 18 and 19.

In this embodiment, the motor rotation amount at which the torque is the largest when cutting a thick branch is near "50", and the motor rotation amount at which the torque value is the largest when cutting the wire is near "70", and different settings are set respectively. Limit. Therefore, when the thick branches are cut, the torque value increases, and the operation stops due to erroneous detection of foreign objects. In addition, because the foreign objects are reliably detected, the wire or the shear will not be damaged.

In addition, the timing of closing the blades 18 and 19 to a predetermined angle can also be used as a reference to switch the effective and invalid of the foreign object detection action, or a maximum value can be set for the threshold value above the predetermined angle to the blade 18. The timing of closing from 19 to a predetermined angle essentially makes the foreign object detection action invalid in advance.

For example, the rotation amount to the motor 12 may be set to a predetermined rotation The amount (for example, "60") does not set a threshold value, but the threshold value is set when the rotation amount of the motor 12 becomes a predetermined rotation amount (for example, "60"). In this way, the timing of increasing the torque when cutting the thick branches (the rotation amount of the motor 12 is near "50"), because the threshold is not set, the detection of foreign objects is not actually performed, and the false detection of foreign objects The measurement system will not happen. On the other hand, at the timing of increasing the torque when the wire is cut (the rotation amount of the motor 12 is near "70"), since the detection of foreign objects is performed, foreign objects can be reliably detected.

In addition, by not monitoring the torque value of the motor 12, but monitoring the amount of change in the torque, the effect of foreign object detection can be improved. That is, when the branch is cut as shown in FIG. 8, the blade part surely penetrates the branch with the closing operation of the blade parts 18 and 19, so the torque of the motor 12 starts to increase relatively slowly, but when cutting the wire, etc. In the case of foreign matter, since the blade portions 18 and 19 do not penetrate, the twist is rapidly increased. By focusing on the rate of change of the torque value that is different for each cutting object, the accuracy of foreign object detection can be improved. In addition, since the judgment is based on the method of increasing the torque when the blades 18 and 19 come into contact with the object to be cut, the effect on the electric shear 10 or the wire can be minimized.

At this time, as long as the rate of change of the torque of the motor 12 is less than the predetermined threshold, it is judged that the branch is cut, and if the rate of change of the torque of the motor 12 is above the predetermined threshold, it is sufficient to judge that a foreign object is caught. The predetermined threshold value compared with the rate of change of torque can also be a fixed value or an upper limit waveform (or lower limit waveform). When the predetermined threshold value is a fixed value, it is sufficient to compare this fixed value with the change amount of the torque of the motor 12 within a fixed time. When the predetermined threshold value is the upper limit waveform (or lower limit waveform), it is sufficient to compare this with the upper limit waveform (or lower limit waveform) and the change waveform of the torque of the motor 12.

In addition, as shown by the waveform Z, when the general thin branches are cut, since the torque of the motor 12 does not become so large, the erroneous detection of foreign objects does not occur.

However, according to the types of branches, it is impossible to conclude that when the thin and hard branches are cut, there is no possibility that the thin and hard branches are judged as foreign objects such as iron wires. Therefore, the electric shear 10 of the present embodiment has a foreign object detection mode that performs foreign object detection and a continuous execution mode that does not perform foreign object detection. In the continuous execution mode, step S102, step S103, and step S106 of the flowchart are not executed, and foreign object detection is not executed even after the blade portions 18, 19 are closed to a predetermined angle. Therefore, in the case of cutting thin and hard branches, by switching to the continuous execution mode, the false detection of foreign objects can be avoided.

When the above mode is switched, the operating member 22 is operated in a direction different from that during the cutting operation. That is, the second operating portion 22d of the operating member 22 is operated. When the second operating portion 22d of the operating member 22 is operated, this operation is detected by the sensor 25. When the sensor 25 detects that the second operation unit 22d is operated, the sensor 25 transmits a control signal to the control device. The control device receiving this control signal changes the operation mode. Specifically, if it is in the foreign object detection mode, it shifts to the continuous execution mode, and if it is the continuous execution mode, it shifts to the foreign object detection mode. The selected mode is held by the second operating part 22d of the operating member 22 and is operated again, and the selected mode is applied to the subsequent operation.

In addition, the operation mode is also restored after the power of the electric shear 10 is lost. That is, when the power of the electric shear 10 is lost in the state of the foreign object detection mode, the electric shear 10 is started in the state of the foreign object detection mode when the power is turned on next time. In addition, when the power supply of the electric shear 10 is lost in the continuous execution mode, the following When the power is turned on for the second time, the electric shear 10 is started in the state of continuous execution mode.

In the present embodiment, the operation mode is switched by the second operating portion 22d of the operating member 22, but the operation mode is not limited to this, and the operation mode may be switched by other operation means. It can also be changed to another mode by restarting after losing power.

In addition, the cable 30 used in the electric shear 10 includes the connection terminal 32 shown in FIG. 9. The connection terminal 32 of the cable 30 includes a plurality of female pins 34A to 34N, and the female pins 34A to 34N are connected to the cable connection portion 11 of the electric shear 10 and the cable connection portion 43 of the power supply device 40.

A plurality of core wires 31 pass through the inside of the cable 30 and are used as signal lines or power lines, respectively. The core wire 31 of this embodiment is shown in FIG. 9(a), at least one of the core wires 31 is branched into two near the connection terminal 32, and a branching portion 33 is formed. The bifurcated core wires 31 are electrically connected to other female pins, respectively. Therefore, in the example shown in FIG. 9(a), the female pin 34A and the female pin 34K are used to transmit the same signal or power, and the female pin 34M and the female pin 34F are used to transmit the same signal or power. In this way, by providing a plurality of female pins on one signal line or power line, even if poor contact occurs in the terminal part (mother pin, male pin), other terminal parts (mother pin, male pin) can be used to maintain the function . In addition, by increasing the number of terminals that transmit the same signal or power, contact resistance can be reduced and malfunctions can be prevented.

In addition, in the above example, the core wire 31 is made to bifurcate, but alternatively, as shown in FIG. 9(b), a plurality of core wires 35A to 35D may be provided for one signal line or power line. That is, in the example shown in FIG. 9(b), the female pin 34A and the female pin 34K are used to transmit the same signal or power, and the corresponding core wire 35A and core wire 35B are used to transmit the same signal or power. Also, the mother pin 34M and The female pin 34F is used to transmit the same signal or power, and the corresponding core wire 35C and core wire 35D are used to transmit the same signal or power. In the case of this configuration, the same effect as the example shown in FIG. 9(a) can also be obtained.

In addition, the examples shown in FIGS. 9(a) and 9(b) may be substituted, or the resistance to contact resistance may be considered together with the examples shown in FIGS. 9(a) and 9(b), Change the configuration of parent pins 34A~34N. That is, since the resistance value of the resistor connected to each signal line or power line differs in circuit configuration, the resistance of each signal line or power line to contact resistance differs. Can also consider the resistance to contact resistance, set the configuration of the female pins 34A~34N.

Specifically, as shown in FIG. 10, when there are 10 female pins 34A to 34J arranged on the outer side and four female pins 34K to 34N arranged on the inner side, the one with greater resistance to contact resistance is arranged On the outer side, the one with less resistance to contact resistance is arranged on the inner side. By arranging in this way, it is possible to make a structure in which poor contact or malfunction is difficult to occur. That is, when a load acts on the connection terminal 32 of the cable 30, the female pins 34A to 34J on the outer side are easily subjected to the load. By connecting signal lines or power lines with high resistance to contact resistance to the female pins 34A to 34J outside the load-bearing side in this way, the effects of sliding wear and the like can be minimized.

As a specific configuration, a method of sequentially assigning inner female pins 34K to 34N from signal lines or power lines with low resistance to contact resistance, and allocating the remaining signal lines or electric power lines to outer female pins 34A to 34J.

As another arrangement, a method of allocating a signal line with low resistance to contact resistance to the inner female pins 34K to 34N, and allocating the remaining signal lines or power lines to the outer female pins 34A to 34J. In this configuration, the power line is arranged on the outside, because the corrosion of the power line due to sliding friction is Signal lines are more difficult to accumulate, so the contact resistance is more difficult to increase than signal lines.

In addition, as shown in FIGS. 9(a) and 9(b), when a plurality of female pins correspond to one signal line or power line, it is preferable to arrange at least one female pin on the inner side. By arranging the two female pins on the inside as much as possible, the failure can be effectively prevented.

As shown in the above description, according to the present embodiment, by comparing the torque information of the motor 12 with the threshold set according to the angle of the blades 18, 19, foreign objects are detected. According to this configuration, objects to be cut such as trees can be surely cut, and foreign objects can be detected when a thin and hard wire or the like is to be cut.

That is, when the object to be cut, such as a tree, is cut, because the object to be cut, such as a tree, is relatively thick, the torsion force becomes maximum before the blades 18 and 19 are completely closed. Furthermore, as the blade portions 18 and 19 are gradually closed, the torque gradually decreases. On the other hand, when a thin and hard foreign object such as an iron wire is cut, the torque becomes maximum immediately before the blade is completely closed.

Furthermore, the present inventors focused on the difference in the torque variation of each cutting object, and made the timing of closing the blade portions 18 and 19 to a predetermined angle as a reference to switch the effectiveness and ineffectiveness of the foreign object detection operation. In this way, the foreign object detection method is that the maximum torque when cutting the object to be cut is not detected, but the maximum torque when cutting foreign objects such as wire is detected, so by detecting the abnormal increase in torque, it can be Detection of foreign objects caught.

Moreover, such a foreign object can be detected without providing a dedicated sensor or circuit.

Also, it has a foreign object detection mode for performing foreign object detection Continuous execution mode for detecting foreign objects, and includes switching means for switching between these two modes. According to this configuration, for example, when the thin and hard branches are cut, the continuous execution mode can be switched, so that the problem of erroneous detection of the insertion of foreign objects can be avoided.

In addition, when the foreign object detection means detects a foreign object, the motor 12 is stopped. According to this configuration, since the cutting operation is not further performed when a foreign object is detected, it is possible to avoid the problem of cutting the wire, or the blade collapse of the blade portions 18 and 19.

In addition, when the foreign object detection means detects a foreign object, the motor 12 is reversed. According to this configuration, since it is not only that the cutting operation is not further performed when the foreign object is detected, but the foreign object sandwiched by the blade portions 18 and 19 is released, it is possible to avoid cutting the wire or cutting the blade The problem.

In addition, in the above embodiment, the current value of the motor 12 is used to estimate the slope of the torque value of the motor 12 (the amount of change in the torque within a predetermined time), thereby detecting foreign objects. However, the embodiment of the present invention is not limited to this, and the torque value of the motor 12 may be estimated based on the voltage value of the motor 12 or the rotation speed of the motor 12 not based on the current value of the motor 12. In addition, when detecting a foreign object, the slope of the torque value of the motor 12 is not calculated, and the torque value of the motor 12 (the current value detected by the current detection unit 120) is directly used to detect the foreign object. However, if the slope of the torque value of the motor 12 is used, since the rise of the torque when starting to cut off foreign objects can be grasped, the inclusion of foreign objects can be detected immediately.

Moreover, in the above-mentioned embodiment, as a method of determining that the blades 18 and 19 are closed to a predetermined angle, a method of measuring the rotation amount of the motor 12 is used. However, the embodiment of the present invention is not limited to this. For example, it can also be made to measure the operating time of the motor 12, when the operating time of the motor 12 reaches a fixed time After that, it is judged that the blade portions 18, 19 have been closed to a predetermined angle. Alternatively, the position of the drive shaft 15a of the link mechanism 15 may be detected, and after the drive shaft 15a of the link mechanism 15 moves to a predetermined position, it may be judged that the blade portions 18, 19 have been closed to a predetermined angle.

In addition, in the above-described embodiment, as an error process when a foreign object is detected, the motor 12 is stopped and the motor 12 is reversed. However, the embodiment of the present invention is not limited to this, and it is also possible to just stop the motor 12. In addition, the speaker 41 or the LED 42 may be used to notify the user of the abnormality. If the user is notified of the abnormality, the user can immediately recognize and deal with the detection of foreign objects. For example, the user can choose whether to continue the cutting operation.

In addition, in the above-mentioned embodiment, as a method of stopping the cutting operation in error processing, the motor 12 is controlled to stop the cutting operation. However, the embodiment of the present invention is not limited to this.

For example, when the foreign object detection means detects a foreign object, the power path may be physically cut so that the power of the motor 12 will not be transmitted to the two blade portions 18 and 19. In the case configured in this manner, since the cutting operation is not further performed when a foreign object is detected, it is possible to avoid the problem of cutting the wire or cutting the blade. The cutting off of the power path may be done by, for example, disengaging the gears.

As another method, a clutch mechanism including adjusting the torque of the motor 12 transmitted to the two blade portions 18 and 19 may be made to make the clutch mechanism effective when the foreign object detection means detects a foreign object. In the case configured in this way, since the upper limit value of the torque is lowered when a foreign object is detected, it can be a problem that the torque at a level where the blade collapses does not occur. As the clutch mechanism, for example, a well-known spring clutch may be used. As long as it is made in clutch When the torque mechanism is invalid, the torque is completely transmitted, but when the clutch mechanism is valid, the torque that exceeds the allowable amount of torque transmission is not transmitted.

In addition, the electric shear 10 of the above-mentioned embodiment is a double-blade movable type in which both blades 18 and 19 are movable, but it is not limited to this. It is a single blade in which one blade is fixed and the other blade is moved. The movable electric shear 10 can also be applied to the present invention in the same manner.

(About modified example of foreign object detection motion)

In the above embodiment, the foreign object detection operation is performed based on the closing angles of the two blade portions 18 and 19 and the amount of change in the current value within a fixed time, but instead, the foreign object detection operation is performed by the method shown below , You can get the same effect.

(First modification)

In this modification, foreign object detection is performed based on whether the current value is above a predetermined threshold.

That is, as shown in FIG. 11, in step S200, the operating member 22 is operated, and the motor 12 starts driving.

In step S202, at regular intervals, the current detection unit 120 measures the current value. This current value is obtained and used as the torque information of the motor 12 used in foreign object detection. Then, it moves to step S203.

In step S203, the foreign object detection means checks whether the current value obtained in step S202 exceeds the preset threshold. When the current value exceeds the threshold, it is judged that a foreign object is caught, and the process moves to step S206. On the other hand, when the current value does not exceed the threshold, the process moves to step S204.

When moving to step S204, check whether the two blades 18, 19 are Fully closed. If it is detected that the two blade portions 18 and 19 are completely closed, the process moves to step S205. On the other hand, if the two blade portions 18 and 19 are not fully closed, the process returns to step S202.

When the process moves to step S205, the motor 12 is stopped, and the process is ended.

In the case of moving to step S206, that is, in the case where it is judged in step S203 that a foreign substance is caught, predetermined error processing is performed. For example, the motor 12 is stopped, and the motor 12 is reversed.

In addition, in the above-mentioned modification, the current value is obtained as the torque information of the motor 12, but alternatively, the voltage value supplied to the electric shear 10 is measured and the voltage value is obtained as the torque information of the motor 12.

(Second modification)

In this modification, a foreign object detection operation is performed based on whether the amount of change in the current value is above a predetermined threshold.

That is, as shown in FIG. 11, in step S200, the operating member 22 is operated, and the motor 12 starts driving.

In step S202, at regular intervals, the current detection unit 120 measures the current value. Based on this current value, the current change amount calculation unit 130 calculates the change amount of the current value within a fixed time. The amount of change in the current value is obtained and used as the torque information of the motor 12 used in foreign object detection. Then, it moves to step S203.

In step S203, the foreign object detection means checks whether the amount of change in the current value obtained in step S202 exceeds a preset threshold. When the amount of change in the current value exceeds the threshold value, it is determined that a foreign object is caught, and the process moves to step S206. On the other hand, when the amount of change in the current value does not exceed the threshold, the process moves to step S204.

When moving to step S204, check whether the two blades 18, 19 are Fully closed. If it is detected that the two blade portions 18 and 19 are completely closed, the process moves to step S205. On the other hand, if the two blade portions 18 and 19 are not fully closed, the process returns to step S202.

When the process moves to step S205, the motor 12 is stopped, and the process is ended.

In the case of moving to step S206, that is, in the case where it is judged in step S203 that a foreign substance is caught, predetermined error processing is performed. For example, the motor 12 is stopped, and the motor 12 is reversed.

(Third Modification)

In this modification, a foreign object detection operation is performed based on whether the angle change of the two blade portions 18 and 19 is above a predetermined threshold.

That is, as shown in FIG. 11, in step S200, the operating member 22 is operated, and the motor 12 starts driving.

In step S202, based on the information about the amount of rotation of the motor 12 obtained from the rotation determination unit 110, the angular change (angular velocity) of the two blade portions 18, 19 is estimated. For example, the number of rotations of the motor 12 at a fixed time is used as the angular velocity information. The information of this angular velocity is acquired and used as the torque information of the motor 12 used in foreign object detection. Then, it moves to step S203.

In step S203, the foreign object detection means checks whether the angular velocity obtained in step S202 is less than the preset threshold value. When the angular velocity is less than the threshold value, it is determined that a foreign object is caught, and the process moves to step S206. On the other hand, when the angular velocity is equal to or greater than the threshold value, the process moves to step S204.

When moving to step S204, it is checked whether the two blade portions 18 and 19 are completely closed. If it is detected that the two blade portions 18 and 19 are completely closed, the process moves to step S205. On the other hand, if the two blades 18, 19 are not completely closed State, return to step S202.

When the process moves to step S205, the motor 12 is stopped, and the process is ended.

In the case of moving to step S206, that is, in the case where it is judged in step S203 that a foreign substance is caught, predetermined error processing is performed. For example, the motor 12 is stopped, and the motor 12 is reversed.

In this way, in this modification, if the amount of change (angular velocity) of the angle of the two blades 18, 19 is more than a predetermined threshold, it is judged to cut the branch, and if the amount of change (angular velocity) of the angle is less than the predetermined threshold Value, to judge the inclusion of foreign objects. Therefore, it can be judged that the branches are cut when the closing speed of the two blades 18 and 19 is slightly reduced, and foreign objects are caught when the closing speed of the two blades 18 and 19 is greatly reduced.

(Fourth Modification)

In this modified example, a foreign object detection operation is performed based on whether the amount of change in the angular velocity of the two blade portions 18 and 19 is greater than a predetermined threshold.

That is, as shown in FIG. 11, in step S200, the operating member 22 is operated, and the motor 12 starts driving.

In step S202, the amount of change in angular velocity (angular acceleration) of the two blade portions 18, 19 is estimated based on the information about the amount of rotation of the motor 12 obtained from the rotation determination unit 110. For example, the number of rotations of the motor 12 at a fixed time is obtained according to a predetermined period, and then the angular acceleration is calculated based on the difference from the number of rotations of the motor 12 obtained last time. This angular acceleration is obtained and used as the torque information of the motor 12 used in foreign object detection. Then, it moves to step S203.

In step S203, the foreign object detection means checks whether the angular acceleration obtained in step S202 is less than the preset threshold value. When the angular acceleration is less than the threshold value, it is determined that a foreign object is caught, and the process moves to step S206. On the other hand, in the corner When the acceleration is equal to or greater than the threshold value, the process moves to step S204.

When moving to step S204, it is checked whether the two blade portions 18 and 19 are completely closed. If it is detected that the two blade portions 18 and 19 are completely closed, the process moves to step S205. On the other hand, if the two blade portions 18 and 19 are not fully closed, the process returns to step S202.

When the process moves to step S205, the motor 12 is stopped, and the process is ended.

In the case of moving to step S206, that is, in the case where it is judged in step S203 that a foreign substance is caught, predetermined error processing is performed. For example, the motor 12 is stopped, and the motor 12 is reversed.

In this way, in this modification, if the angular acceleration is greater than or equal to the predetermined threshold, it is determined that the branch is cut, and if the angular acceleration is less than the predetermined threshold, it is determined that a foreign object is caught. Therefore, it can be judged that the branch is cut when the closing speed of the two blades 18 and 19 is slowly decreased, and foreign objects are caught when the closing speed of the two blades 18 and 19 is rapidly decreased.

(Fifth Modification)

In this modification, the foreign object detection operation is performed based on the closing angles and current values of the two blade portions 18 and 19.

That is, as shown in FIG. 7, in step S100, the operating member 22 is operated, and the motor 12 starts driving.

In step S101, the rotation determination unit 110 obtains the rotation amount of the motor 12. Then, it moves to step S102.

In step S102, at regular intervals, the current detection unit 120 measures the current value. This current value is obtained and used as the torque information of the motor 12 used in foreign object detection. Then, it moves to step S103.

In step S103, the current determination unit 140 obtains information on the rotation amount of the motor 12 from the rotation determination unit 110, and estimates the closing angle of the two blade portions 18, 19. Then, according to this closing angle, the threshold value is selected from the preset threshold value data. The selected threshold value is compared with the current value obtained in step S102. When the current value exceeds the threshold, it is judged that a foreign object is caught, and the process moves to step S106. On the other hand, when the current value does not exceed the threshold, the process moves to step S104.

When moving to step S104, it is checked whether the two blade parts 18 and 19 are fully closed. If it is detected that the two blade portions 18 and 19 are completely closed, the process moves to step S105. On the other hand, if the two blade portions 18 and 19 are not fully closed, the process returns to step S101.

When the process moves to step S105, the motor 12 is stopped, and the process is ended.

When the process moves to step S106, that is, when it is judged that a foreign object is caught in step S103, predetermined error processing is performed. For example, the motor 12 is stopped, and the motor 12 is reversed.

(Sixth modification)

In this modification, the foreign object detection operation is performed based on the angle change (angular velocity) and current value of the two blade portions 18 and 19.

That is, as shown in FIG. 7, in step S100, the operating member 22 is operated, and the motor 12 starts driving.

In step S101, based on the information about the amount of rotation of the motor 12 obtained from the rotation determination unit 110, the angular change (angular velocity) of the two blade portions 18, 19 is estimated. For example, the number of rotations of the motor 12 at a fixed time is used as the angular velocity information. Then, it moves to step S102.

In step S102, the current detection unit 120 measures the current value at fixed intervals. Then, it moves to step S103.

In step S103, it is checked whether the angular velocity obtained in step S101 is less than the preset threshold value and whether the current value obtained in step S102 is above the preset threshold value. When the angular velocity is less than the threshold value and the current value is greater than the threshold value, it is determined that a foreign object has been caught, and the process moves to step S106. On the other hand, when the angular velocity is equal to or greater than the threshold value or the current value is less than the threshold value, the process moves to step S104.

When moving to step S104, it is checked whether the two blade parts 18 and 19 are fully closed. If it is detected that the two blade portions 18 and 19 are completely closed, the process moves to step S105. On the other hand, if the two blade portions 18 and 19 are not fully closed, the process returns to step S101.

When the process moves to step S105, the motor 12 is stopped, and the process is ended.

When the process moves to step S106, that is, when it is judged that a foreign substance is caught in step S103, predetermined error processing is performed. For example, the motor 12 is stopped, and the motor 12 is reversed.

(Seventh Modification)

In this modification, the foreign object detection operation is performed based on the angle change (angular velocity) of the two blade portions 18 and 19 and the amount of change in the current value.

That is, as shown in FIG. 7, in step S100, the operating member 22 is operated, and the motor 12 starts driving.

In step S101, based on the information about the amount of rotation of the motor 12 obtained from the rotation determination unit 110, the angular change (angular velocity) of the two blade portions 18, 19 is estimated. For example, taking the number of rotations of the motor 12 at a fixed time as the angular velocity News. Then, it moves to step S102.

In step S102, the current detection unit 120 measures the current value at fixed intervals. Based on this current value, the current change amount calculation unit 130 calculates the change amount of the current value within a fixed time. Then, it moves to step S103.

In step S103, it is checked whether the angular velocity obtained in step S101 is less than the preset threshold, and whether the amount of change in the current value obtained in step S102 is greater than the preset threshold. When the angular velocity is less than the threshold value and the amount of change in the current value is greater than the threshold value, it is determined that a foreign object has been caught, and the process moves to step S106. On the other hand, when the angular velocity is equal to or greater than the threshold, or the amount of change in the current value is less than the threshold, the process moves to step S104.

When moving to step S104, it is checked whether the two blade parts 18 and 19 are fully closed. If it is detected that the two blade portions 18 and 19 are completely closed, the process moves to step S105. On the other hand, if the two blade portions 18 and 19 are not fully closed, the process returns to step S101.

When the process moves to step S105, the motor 12 is stopped, and the process is ended.

When the process moves to step S106, that is, when it is judged that a foreign substance is caught in step S103, predetermined error processing is performed. For example, the motor 12 is stopped, and the motor 12 is reversed.

(8th modification)

In this modification, the foreign object detection operation is performed based on the output duty ratio of the motor 12 and the amount of change in the current value.

That is, as shown in FIG. 11, in step S200, the operating member 22 is operated, and the motor 12 starts driving.

In step S202, at regular intervals, the current detection unit 120 measures the current value. This current value is obtained and used as the torque information of the motor 12 used in foreign object detection. Then, it moves to step S203.

In step S203, a threshold value is selected from preset threshold data according to the output duty ratio of the motor 12. This threshold value is set to be proportional to the output task ratio, and becomes higher stepwise or steplessly. Furthermore, it is checked whether the current value obtained in step S202 exceeds the selected threshold value. When the current value exceeds the threshold, it is judged that a foreign object is caught, and the process moves to step S206. On the other hand, when the current value does not exceed the threshold, the process moves to step S204.

When moving to step S204, it is checked whether the two blade portions 18 and 19 are completely closed. If it is detected that the two blade portions 18 and 19 are completely closed, the process moves to step S205. On the other hand, if the two blade portions 18 and 19 are not fully closed, the process returns to step S202.

When the process moves to step S205, the motor 12 is stopped, and the process is ended.

In the case of moving to step S206, that is, in the case where it is judged in step S203 that a foreign substance is caught, predetermined error processing is performed. For example, the motor 12 is stopped, and the motor 12 is reversed.

If the threshold value is determined by referring to the output task ratio of the motor 12 in this way, the accuracy of foreign object detection can be improved more than when only the current value is referenced. That is, even if the current values are the same, if the output task ratio is different, the output of the motor 12 is different, so by referring to both the current value and the output task ratio, the accuracy of foreign object detection can be improved.

(Ninth Modification)

In this modification, foreign object detection is performed based on the current value and voltage value.

That is, as shown in FIG. 11, in step S200, the operation member 22 is operated, and The motor 12 starts to drive.

In step S202, the current value and the voltage value are measured at fixed intervals, and the power value (current value×voltage value) is calculated. This electric power value is obtained and used as the torque information of the motor 12 used for foreign object detection. Then, it moves to step S203.

In step S203, the foreign object detection means checks whether the power value obtained in step S202 exceeds the preset threshold value. When the electric power value exceeds the threshold value, it is judged that a foreign object is caught, and the process moves to step S206. On the other hand, when the power value does not exceed the threshold, the process moves to step S204.

When moving to step S204, it is checked whether the two blade portions 18 and 19 are completely closed. If it is detected that the two blade portions 18 and 19 are completely closed, the process moves to step S205. On the other hand, if the two blade portions 18 and 19 are not fully closed, the process returns to step S202.

When the process moves to step S205, the motor 12 is stopped, and the process is ended.

In the case of moving to step S206, that is, in the case where it is judged in step S203 that a foreign substance is caught, predetermined error processing is performed. For example, the motor 12 is stopped, and the motor 12 is reversed.

If foreign objects are detected in accordance with the current value and the voltage value in this way, even the machinery whose voltage value changes according to the use situation (such as the rechargeable tool of this embodiment), because the output of the motor can be accurately grasped (Cut off the load), so it can improve the accuracy of foreign object detection.

S100‧‧‧trigger operation detected, motor driven

S101‧‧‧Get the motor rotation

S102‧‧‧Get torque information of motor

S103‧‧‧ Has a foreign object been detected?

S104‧‧‧ Has the closed position been detected?

S105‧‧‧stop the motor

S106‧‧‧Error handling

Claims (10)

A foreign object detection mechanism of an electric shear is an electric shear including a blade portion linked with the rotation of a motor, and a foreign object detection mechanism that detects an electric shear caught in a foreign object, and is characterized by including: Foreign object detection means; the detection of foreign objects by the foreign object detection means is performed based on the angle information of the blade and the torque information of the motor; as the torque information of the motor, the rate of change of the torque of the motor is used; If the rate of change of the torque of the motor is less than the predetermined threshold, the branch is judged to be cut, and if the rate of change of the torque of the motor is above the predetermined threshold, it is judged that a foreign object is caught. For example, the foreign body detection mechanism of the electric shear in item 1 of the patent scope, wherein the foreign body detection means selects the threshold value from the preset threshold value data according to the closing angle of the blade, and compares the threshold value Value and torque information of the motor to detect foreign objects. For example, the foreign object detection mechanism of the electric shear in item 1 of the patent scope, wherein the torque information of the motor is estimated based on any one of the current value, voltage value or rotation speed of the motor. For example, the foreign object detection mechanism of the electric shear according to any one of the items 1 to 3 of the patent application range, wherein the detection of the foreign object by the foreign object detection means is to judge that the blade portion is closed to a predetermined angle is invalid, after the judgment has been It becomes effective after the blade is closed to a predetermined angle. Foreign object detection such as electric shears according to any of items 1 to 3 of the patent application The mechanism has a foreign object detection mode that performs foreign object detection and a continuous execution mode that does not perform foreign object detection; including a switching method for switching between these two modes. For example, the foreign object detection mechanism of the electric shear according to any one of the items 1 to 3 of the patent application scope, wherein when the foreign object detection means detects a foreign object, the motor is stopped. The foreign object detection mechanism of an electric shear according to any one of the items 1 to 3 of the patent application scope, wherein when the foreign object detection means detects a foreign object, the motor is reversed. For example, the foreign object detection mechanism of the electric shear according to any one of the items 1 to 3 of the patent application scope, wherein when the foreign object detection means detects the foreign object, the user is notified of the abnormality. For example, the foreign object detection mechanism of the electric shear according to any one of the items 1 to 3 of the patent application scope, wherein when the foreign object detection means detects a foreign object, the power path is physically cut off to the power of the motor. To the blade. For example, the foreign object detection mechanism of the electric shear according to any one of the items 1 to 3 of the patent application scope includes a clutch mechanism for adjusting the torque of the motor transmitted to the blade; when the foreign object detection means detects a foreign object, Make this clutch mechanism effective.

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