Power tool

Abstract

To provide an electric tool having a structure excellent in safety, which can easily align the workpiece by clamping the workpiece with a constant force and can process the aligned workpiece, thereby reducing the burden on a worker. [Solution] The power tool 1 comprises a main body 2 having an electric motor 7a, a feed screw 8a, a slide portion 9 and a control unit 19, and a tool head 3 connected to the main body 2 and having a first jaw portion 11 and a second jaw portion 12 that are rotatably connected to each other, the slide portion 9 having a first roller 9a and a second roller 9b arranged thereon, and the control unit 19 is configured to control the slide portion 9 to move backward to a position where the workpiece can be machined, to machine the workpiece, and then to move the slide portion 9 forward to a position where the machined workpiece can be removed.

Description

[Technical field]

[0001] The present invention relates to a power tool for machining a workpiece. [Background technology]

[0002] Conventionally, there is known an electric tool that combines a crank-type gripping lever and an electric motor (Patent Document 1: European Patent Specification No. 2872293). In the electric tool of Patent Document 1, the tip side of the tool head is open in the initial state, and the tip side of the tool head is closed by the gripping force of the operator gripping the gripping lever to clamp the workpiece. When the gripping force exceeds a specified value, the electric motor is operated, and the tip side of the tool head is closed to process the workpiece. [Prior art documents] [Patent documents]

[0003] [Patent Document 1] European Patent No. 2872293 Summary of the Invention [Problem to be solved by the invention]

[0004] When crimping a crimp terminal to an electric wire at a work site, it is necessary to align the crimp terminal with the electric wire. Also, when compressing a crimp sleeve to join electric wires at a work site, it is necessary to align the compression sleeve with each electric wire.

[0005] However, the electric power tool of Patent Document 1 requires the operator to align the crimp terminal and the electric wire and the compression sleeve and the electric wire while holding the gripping lever with a gripping force that does not exceed a specified value, which places a heavy burden on the operator. In other words, when the gripping force of the gripping lever by the operator falls below a specified value, the tip side of the tool head opens, causing the workpiece, such as the compression terminal or the crimping sleeve, to fall off. On the other hand, when the gripping force of the gripping lever by the operator exceeds a specified value, the electric motor starts to operate and the workpiece is processed, so that the tip side of the tool head closes before the workpiece is aligned, causing the compression terminal or the crimping sleeve to be poorly processed. In addition, the tip side of the tool head of the electric power tool of Patent Document 1 is open in the initial state, so the operator must handle the tool carefully when starting work to avoid accidentally injuring his or her hands. [Means for solving the problem]

[0006] The present invention has been made in consideration of the above-mentioned circumstances, and aims to provide an electric tool having a configuration that allows the workpiece to be easily aligned by clamping it with a constant force, and that enables the workpiece to be processed in an aligned state, thereby reducing the burden on the operator and providing an excellent structure for safety.

[0007] In one embodiment, the above problem is solved by the solution disclosed below.

[0008] The electric tool according to the present invention comprises a main body having an electric motor, a feed screw operated by the electric motor, a slide unit moved by the feed screw, and a control unit, and a tool head connected to the main body and having a first jaw unit and a second jaw unit rotatably connected to each other, the tool head is provided with a spring that biases the tip side of the first jaw unit and the tip side of the second jaw unit in a direction to bring them closer to each other, and is configured to machine a workpiece by a first shaped portion on the tip side of the first jaw unit and a second shaped portion on the tip side of the second jaw unit, the slide unit has a first roller arranged at a position slidable on the rear end side of the first jaw unit and a second roller arranged at a position slidable on the rear end side of the second jaw unit, and the control unit is configured to control the slide unit to move backward to a position where the workpiece can be machined, machine the workpiece, and then move the slide unit forward to a position where the machined workpiece can be removed. The main body has a trigger switch, a control switch, and an intermediate switch that is actuated by the movement of the slide portion to an intermediate position, and when the intermediate switch is in an ON state, an operator operates the control switch, whereby the control unit controls switching between an automatic mode in which the workpiece is repeatedly machined from a state in which the tip side of the first jaw and the tip side of the second jaw are open, and a manual mode in which the workpiece is machined one at a time from a state in which the tip side of the first jaw and the tip side of the second jaw are closed. It is characterized by the above.

[0009] According to this configuration, the tip side of the tool head is closed when the slide part is in the intermediate position in the initial state, which provides excellent safety. Furthermore, the control unit drives and controls the electric motor to move the slide part with the feed screw to clamp the workpiece, which makes it easy to align the workpiece. The workpiece is then processed accurately and reliably by moving the slide part. This reduces the burden on the operator compared to conventional products, resulting in a structure with excellent safety.

[0010] The tool head is configured such that a spring is disposed to bias the tip side of the first jaw portion and the tip side of the second jaw portion in a direction to approach each other. With this configuration, the workpiece can be securely clamped with a constant force while having a simpler configuration than a crank or link.

[0011] The second jaw is preferably configured to have an operation part that, when the slide part is in the intermediate position, allows the operator to move the first shaped part and the second shaped part away from each other to make the workpiece removable. According to this configuration, when the slide part is in the intermediate position, the operator presses the operation part in the second jaw, so that the tip side of the second jaw moves away from the tip side of the first jaw, making it easy to attach and align the workpiece. This makes the configuration easy to use. As an example, the main body has a cover part, and the operation part in the second jaw has a guide plate attached at a position where the operator presses the guide plate, which has a shape corresponding to the operator's finger. The cover part can be a resin molded product, or a metal pressed product with an insulating treatment applied to the inner wall.

[0012] The main body is preferably configured to include a trigger switch that operates in conjunction with a trigger lever operated by the operator so that the control unit drives the electric motor, and a control switch that is operated by the operator so that the control unit activates the trigger switch. The intermediate switch is preferably configured to be operated by the movement of the slide unit to an intermediate position so that the control unit stops the electric motor, and when the slide unit is in the intermediate position, the rear end side of the first jaw is separated from the first roller, and the rear end side of the second jaw is separated from the second roller. With this configuration, the simple configuration of a control switch and a trigger switch is combined, and the operator can easily perform a series of required operations with one hand while taking safety into consideration. This configuration is therefore easy to use. It is preferable that the main body has a trigger switch, a control switch, and an intermediate switch that is actuated by the movement of the slide part to an intermediate position, and when the intermediate switch is in an ON state, an operator operates the control switch to control the control unit to switch between an automatic mode in which the workpiece is repeatedly machined from a state in which the tip side of the first jaw and the tip side of the second jaw are open, and a manual mode in which the workpiece is machined once each from a state in which the tip side of the first jaw and the tip side of the second jaw are closed. It is also preferable that the operator operates the trigger switch to cause the control unit to drive and control the electric motor, so that the workpiece can be machined when the trigger switch is in an ON state, and that the control unit stops the electric motor when the intermediate switch is activated, so that the machined workpiece can be removed when the electric motor is stopped.

[0013] The main body is preferably configured to include an upper limit switch that is activated by the movement of the slide part to the upper limit position so that the control unit stops the electric motor, an intermediate switch that is activated by the movement of the slide part to the intermediate position so that the control unit stops the electric motor, and a lower limit switch that is activated by the movement of the slide part to the lower limit position so that the control unit stops the electric motor. With this configuration, it is possible to prevent a load greater than necessary from being applied to the tool head, and to easily perform desired control accurately and reliably, even with a simple configuration in which multiple switches are arranged. The main body is preferably configured to include a lower limit switch that is activated by the movement of the slide part to the lower limit position and an upper limit switch that is activated by the movement of the slide part to the upper limit position, and is configured to be in a state in which the workpiece is machined when the lower limit switch is in an ON state, and is configured to be able to remove the machined workpiece when the upper limit switch is in an ON state after the workpiece is machined.

[0014] As an example, the feed screw is supported by a bearing and connected to the electric motor via a reducer. With this configuration, rotational friction caused by a thrust load received when the feed screw moves the slide part can be reduced. As an example, the slide part is connected to a nut that converts the rotational motion of the feed screw into linear motion, or the slide part is integral with the nut. The feed screw may be a ball screw. The bearing is a thrust bearing, and as an example, a thrust ball bearing or a thrust roller bearing may be used. Furthermore, by connecting the feed screw to the electric motor via a reducer, it is possible to easily generate high torque with a small electric motor. As an example, the reducer is a gear box composed of multiple gears. The electric motor may be an integral geared motor combined with a reducer.

[0015] As an example, the main body has a battery that supplies power to the electric motor, and the electric motor is driven by the power from the battery to compress, crimp, or cut the workpiece. With this configuration, a power cord is no longer necessary, and the working range can be expanded. Therefore, a compact and easy-to-use structure can be achieved. As an example, the cover part of the main body is shaped like a handle that can be held by an operator in a direction away from the tool head. An adapter is provided below the handle-shaped cover part. As an example, the battery is connected to the adapter in the main body in the form of a battery pack. Effect of the Invention

[0016] According to the present invention, the workpiece can be easily aligned by clamping it with a constant force, and the aligned workpiece can be easily processed. Moreover, since the tip side of the tool head is closed in the initial state where the sliding part is in the intermediate position, a power tool with a structure that reduces the burden on the operator and is superior in safety compared to conventional products can be realized. [Brief description of the drawings]

[0017] [Figure 1] FIG. 1 is a schematic perspective view showing an example of a power tool according to an embodiment of the present invention. [Diagram 2] 2A is a rear view of the power tool shown in FIG. 1, FIG. 2B is a right side view of the power tool shown in FIG. 1, FIG. 2C is a front view of the power tool shown in FIG. 1, and FIG. 2D is a left side view of the power tool shown in FIG. 1. [Diagram 3] 3A is a schematic structural diagram showing the power tool of FIG. 1 with a cover removed, and FIG. 3B is a structural diagram showing the relationship between a trigger lever and a switch board in the power tool of FIG. [Figure 4] 4A is a front view of the tool head of the power tool shown in FIG. 1, and FIG. 4B is a left side view of the tool head of the power tool shown in FIG. [Diagram 5] FIG. 5 is an example of a schematic circuit diagram of the power tool of this embodiment. [Figure 6]6A is a schematic structural diagram showing the initial state when using the power tool shown in FIG. 1, FIG. 6B is a schematic structural diagram showing the state when a workpiece is attached when using the power tool shown in FIG. 1, FIG. 6C is a schematic structural diagram showing the state when the workpiece is compressed or crimped when using the power tool shown in FIG. 1, and FIG. 6D is a schematic structural diagram showing the state when the workpiece is removed when using the power tool shown in FIG. 1. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0018] Hereinafter, an embodiment of the present invention will be described in detail with reference to the drawings. The power tool 1 of this embodiment is configured to compress, crimp, or cut a workpiece 90 by driving an electric motor 7a with power from a battery 5. As an example, the power tool 1 is used when crimping a crimp terminal and an electric wire at a work site, or when compressing a crimp sleeve at a work site to join electric wires. In addition, in all the drawings for explaining the embodiment, members having the same function are given the same reference numerals, and repeated explanations of them may be omitted.

[0019] 1, 2A, 2B, 2C, and 2D are schematic diagrams showing an example of a power tool 1 according to the present embodiment. The power tool 1 is a cordless type tool that includes a main body 2 having an electric motor 7a, a feed screw 8a, a slide portion 9, a control portion 19, and a control switch 21, a tool head 3 having a first jaw portion 11 and a second jaw portion 12 connected to the main body 2 and rotatably connected to each other, and a battery 5, and is used by a worker at a work site. The slide portion 9 reciprocates along an axis P1 of the feed screw 8a. The slide portion 9 advances to an upper limit position in the direction of the Z direction arrow in the figure, and retreats to a lower limit position in the opposite direction to the Z direction arrow in the figure. In the initial state where the slide portion 9 is in an intermediate position, the tip side of the tool head 3 is closed. The example in FIG. 1 is a multi-function power tool 1 in which the tool head 3 can be replaced. Here, in order to easily explain the positional relationship of each part of the power tool 1, the directions are indicated by X, Y, and Z arrows in the figure. The power tool 1 operates normally in either orientation.

[0020] 4A and 4B show an example of a tool head 3 for compression. The first jaw 11 and the second jaw 12 are supported by a first shaft member 17a, and are rotatably connected to each other by a connecting plate 17. The first shape portion 11a at the tip side of the first jaw 11 has inwardly facing convex portions formed at a predetermined interval, and the second shape portion 12a at the tip side of the second jaw 12 has inwardly facing concave portions formed in one-to-one correspondence with the convex portions. The first shape portion 11a at the tip side of the first jaw 11 and the second shape portion 12a at the tip side of the second jaw 12 approach each other to compress or crimp a compression terminal or a crimp sleeve as a workpiece 90. The spring 18 is a torsion coil spring made of metal. The coil portion of the spring 18 is rotatably attached to a support portion 11e provided on the first jaw 11. An end of the spring 18 abuts against the connecting plate 17. Then, the restoring force of the spring 18 biases the first shaped portion 11a on the tip side of the first jaw 11 and the second shaped portion 12a on the tip side of the second jaw 12 in directions toward each other.

[0021] Fig. 3A is a schematic structural diagram showing the power tool 1 with the cover 2a of the main body 2 removed, and Fig. 3B is a structural diagram showing the relationship between the trigger lever 27 and the switch board 20a in the power tool 1. As an example, the control switch 21 is a push switch. The trigger lever 27 is rotatably supported by a second shaft member provided in the main body 2, and the trigger switch 22 operates in conjunction with the trigger lever 27. The trigger switch 22 is a microswitch. The switch board 20a is mounted with a plurality of microswitches capable of detecting the position of the sliding portion 9. As an example, the position of the sliding portion 9 is detected when a pin arranged on the sliding portion 9 comes into contact with the microswitch.

[0022] The tool head 3 processes the workpiece 90 by applying the principle of leverage. The first jaw 11 has a first sliding surface 11d on which the first roller 9a slides formed at the rear end side of the first jaw 11, and a first curved portion 11c from the protruding portion 11b of the first jaw 11 to the first sliding surface 11d is carved out so as to be separated from the first roller 9a. The second jaw 12 has a second sliding surface 12d on which the second roller 9b slides formed at the rear end side of the second jaw 12, and a second curved portion 12c from an inner edge portion close to the location where the first shaft member is disposed to the second sliding surface 12d is carved out so as to be separated from the second roller 9b.

[0023] The feed screw 8a is journaled by a bearing 8b and is connected to an electric motor 7a via a reducer 6. The main body 2 has a battery 5 that supplies power to the electric motor 7a, and the electric motor 7a is driven by power from the battery 5 to compress, crimp, or cut the workpiece 90. The cover portion 2a of the main body 2 is shaped like a handle that can be held by an operator in a direction away from the tool head 3. An adapter 4 is provided on the lower end side of the cover portion 2a, and the battery 5 is connected to the adapter 4 of the main body 2 in the form of a battery pack.

[0024] 5 is an example of a circuit diagram of the power tool 1. The control unit 19 has a CPU 19a, which is a one-chip microcomputer, for example. The control unit 19 and the switch board 20a and display board 20b that constitute the peripheral circuits will now be described.

[0025] As an example, the battery 5 is a lithium ion battery, the power supply voltage is 7 to 42 [V], and the battery capacity is 1 to 10 [Ah]. The voltage of the battery 5 is stepped down via a regulator 19c and supplied to the CPU 19a. The CPU 19a is configured to check and monitor the remaining charge of the battery 5, and also functions as a timer. As an example, the CPU 19a sends a PWM signal to a driver 19b, supplies power to the electric motor 7a via a driving element such as a power MOSFET, and controls the driving of the electric motor 7a.

[0026] As an example, the control unit 19, the switch board 20a, and the display board 20b are signal-connected by wiring. The switch board 20a is equipped with a trigger switch 22 that is actuated by operating a trigger lever 27, an upper limit switch 23 that is actuated when the sliding part 9 moves to an upper limit position, an intermediate switch 24 that is actuated when the sliding part 9 moves to an intermediate position, and a lower limit switch 25 that is actuated when the sliding part 9 moves to a lower limit position. The actuation signals of each switch are input to the CPU 19a, which controls the driving of the electric motor 7a.

[0027] The display board 20b is mounted with a control switch 21 operated by an operator, an LED 26a indicating that the power tool 1 is in the automatic mode, an LED 26b indicating that the power tool 1 is in an abnormal state, and an LED 26c indicating that the power tool 1 is in the manual mode. When an actuation signal of the control switch 21 is input to the CPU 19a, the CPU 19a determines that the actuation signal of the trigger switch 22 is a valid signal, and sets the conditions for driving and controlling the electric motor 7a. As an example, the control switch 21 is a push switch, and when the intermediate switch 24 is ON, the control switch 21 is pressed for a predetermined time, for example, for 3 seconds or more, and the mode is switched each time. The automatic mode is used when working continuously, and the LED 26a is turned on by the display control of the CPU 19a, and for example, is displayed in green. The manual mode is used when working once, and the LED 26c is turned on by the display control of the CPU 19a, and for example, is displayed in green.

[0028] When the power tool 1 is in an abnormal state, an abnormality signal is input from an external sensor to the CPU 19a, and the CPU 19a controls the display to turn on or blink the LED 26b, for example, in red. As an example, when the current value of the battery 5 exceeds 20 [A], the LED 26b blinks 10 times at a cycle of 5 Hz. As an example, when the substrate temperature of the control unit 19 reaches 80 [°C], the LED 26b turns on for 3 seconds. As an example, when the temperature of the battery 5 is 90 [°C] or higher, the LED 26b blinks 3 times at a cycle of 1 Hz. As an example, when the voltage of the battery 5 is 7.8 [V] or lower, the LED 26b blinks 10 times at a cycle of 5 Hz. Note that the above values ​​are merely examples and are not limited to the above values.

[0029] As an example, the relationship between the operation of the operator and the operation of the power tool 1 and the operations of the control switch 21, the trigger switch 22, the upper limit switch 23, the intermediate switch 24, and the lower limit switch 25 is shown in Table 1. In Table 1, the first switch is the control switch 21, and the second switch is the trigger switch 22.

[0030] [Table 1]

[0031] As shown in Table 1, the device has a simple configuration combining the control switch 21 and the trigger switch 22 that is linked to the trigger lever 27, yet is easy to use because the operator can easily perform the required series of operations with one hand. Also, it is rational because the power is turned ON when the control switch 21 is activated and the power is turned OFF a predetermined time after the trigger lever 27 is released. As an example, the power is turned OFF 60 seconds after the trigger lever 27 is released.

[0032] 6A to 6D are schematic structural diagrams illustrating the operation of the power tool 1. The operation of the power tool 1 will be described below with reference to FIGS.

[0033] Fig. 6A shows the initial state where the slide portion 9 is in the intermediate position. The intermediate position is a position where the first roller 9a is in contact with or close to the protrusion 11b. When the power is OFF, only the intermediate switch 24 is ON. When the slide portion 9 is in the intermediate position, the tip side of the first jaw portion 11 and the tip side of the second jaw portion 12 are closed by the restoring force of the spring 18. The first crimping operation starts with the slide portion 9 in the initial position shown in Fig. 6A.

[0034] In step S1, when the operator presses and releases the control switch 21, the control switch 21 goes from OFF to ON and then back to OFF, the power is turned ON under the control of the control unit 19, and the operation of the trigger switch 22 becomes effective.

[0035] Following step S1, in step S2, the operator pushes the operating portion 12b of the second jaw 12 toward the first jaw 11, causing the first shaping portion 11a to separate from the second shaping portion 12a, and the operator attaches the workpiece 90. Fig. 6B shows a state in which the workpiece 90 is clamped between the first shaping portion 11a and the second shaping portion 12a.

[0036] Following step S2, in step S3, when the operator grips trigger lever 27, slide portion 9 retreats and moves downward, and first roller 9a slides on first sliding surface 11d while second roller 9b slides on second sliding surface 12d, so that first shaping portion 11a and second shaping portion 12a approach each other and crimp workpiece 90. When slide portion 9 reaches the lower limit position, lower limit switch 25 is actuated and slide portion 9 stops temporarily. Fig. 6C shows the state where workpiece 90 has been crimped.

[0037] Following step S3, in step S4, when the operator releases the trigger lever 27, the slide portion 9 advances and moves upward, and the first roller 9a presses the protruding portion 11b, causing the first shape portion 11a and the second shape portion 12a to move away from each other. When the slide portion 9 reaches the upper limit position, the upper limit switch 23 is activated and the slide portion 9 temporarily stops.

[0038] Following step S4, in step S5, the operator removes the workpiece 90. Fig. 6D shows the state after the workpiece 90 has been removed. After a predetermined time has elapsed since the operator released the trigger lever 27, the power is turned off with the tip side of the first jaw 11 and the tip side of the second jaw 12 closed.

[0039] In the automatic mode, the crimping operation is repeated from the state shown in Fig. 6D, whereas in the manual mode, the crimping operation is performed once from the state shown in Fig. 6A.

[0040] According to this embodiment, the workpiece 90 can be easily aligned by clamping the workpiece 90 with a constant force, and the aligned workpiece 90 can be easily processed. Moreover, in the initial state in which the sliding portion 9 is in the intermediate position, the tip side of the tool head 3 is closed, so the electric power tool 1 has a structure that reduces the burden on the operator and is safer than conventional products.

[0041] In the above example, a case where a compression terminal or a crimping sleeve is compressed or crimped as the workpiece 90 has been described, but the present invention is not limited to this example. This embodiment can be applied to electrical installation tools in general, such as cutting electric wires and crimping electric wires together. In addition, in the above example, a configuration in which the battery 5 is detachably attached to the main body 2 in the form of a battery pack has been described, but the present invention is not limited to this example. This embodiment may be configured such that the battery 5 is built into the main body 2, or may be configured to include both a built-in battery and a battery pack.

[0042] The present invention is not limited to the above-described embodiment, and various modifications are possible without departing from the scope of the present invention. [Explanation of symbols]

[0043] 1 Power tools 2 Main body, 2a Cover 3 Tool Head 4 Adapters 5 Battery 6 Reducer 7a electric motor, 7b drive shaft 8a Lead screw, 8b Bearing 9 Slide portion, 9a First roller, 9b Second roller 11 first jaw portion, 11a first shape portion, 11b protrusion portion, 11c first curved portion, 11d first sliding surface, 11e support portion 12 second jaw portion, 12a second shape portion, 12b operating portion, 12c second curved portion, 12d second sliding surface 17 Connection plate, 17a 1st shaft member 18 Spring 19 control unit, 19a CPU (microcomputer), 19b driver 20a switch board, 20b display board 21 Control Switch 22 Trigger Switch 23 Upper limit switch 24 Intermediate switch 25 Lower limit switch 26a, 26b, 26c LEDs 27 trigger lever, 27a second shaft member 90 Workpiece P1 axis

Claims

1. the tool head is provided with a spring for biasing a tip side of the first jaw and a tip side of the second jaw in a direction to bring them closer to each other, and a workpiece is machined by a first shaped portion on the tip side of the first jaw and a second shaped portion on the tip side of the second jaw, the slide portion has a first roller arranged at a position slidable on the rear end side of the first jaw and a second roller arranged at a position slidable on the rear end side of the second jaw, the control portion is configured to control the slide portion to move backward to a position where the workpiece can be machined and then move forward to a position where the machined workpiece can be removed, The main body has a trigger switch, a control switch, and an intermediate switch that is actuated by the movement of the slide portion to an intermediate position, and when the intermediate switch is in an ON state, an operator operates the control switch, whereby the control unit controls switching between an automatic mode in which the workpiece is repeatedly machined from a state in which the tip side of the first jaw and the tip side of the second jaw are open, and a manual mode in which the workpiece is machined one at a time from a state in which the tip side of the first jaw and the tip side of the second jaw are closed. A power tool characterized by:

2. The control unit controls the drive of the electric motor when the operator operates the trigger switch, and when the trigger switch is in the ON state, the workpiece can be processed. The control unit stops the electric motor when the intermediate switch is activated, and when the electric motor is stopped, the processed workpiece can be removed. The power tool according to claim 1 .

3. The main body has a lower limit switch that is actuated by the movement of the slide part to the lower limit position, and an upper limit switch that is actuated by the movement of the slide part to the upper limit position, and is configured so that the workpiece is in a machined state when the lower limit switch is in an ON state, and after the workpiece is machined, the machined workpiece can be removed when the upper limit switch is in an ON state. The power tool according to claim 1 or 2,

4. The main body has a battery that supplies power to the electric motor, and is configured to drive the electric motor with power from the battery to compress, crimp, or cut the workpiece. The power tool according to any one of claims 1 to 3,

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