Electric tool

Abstract

The present invention addresses the problem of providing an electric tool having a small size and excellent workability and capable of achieving automatic backflow. As a solution, an electric tool (1) is provided with a hydraulic pump (6) for conveying hydraulic oil (4a) to a cylinder part (3), a motor (7), a secondary battery (9), a flow path part (5), a first link fitting (11) for connecting a trigger rod (21) and a start switch (2b), a second link fitting (12) for connecting the trigger rod (21) and a return switch (22), and a spring (23) for biasing the trigger rod (21) in the direction in which the trigger rod (21) is returned. The flow path part (5) is provided with a pressure increasing flow path (5a), a backflow flow path (5b), a one-way valve (25) for opening and closing the backflow flow path (5b), and a backflow pin (24) for opening the backflow flow path (5b) by pressing the one-way valve (25). The trigger lever (21) is configured so as to be disposed on the opposite side from the side on which the backflow switch (22) is disposed with respect to the axis (P1).

Description

Technical Field

[0001] The invention relates to a hydraulic electric tool. Background Art

[0002] Conventionally, a hydraulic cutting tool having the following structure has been proposed: one end side of a start switch rod (synonymous with a trigger rod) is brought into contact with a power switch (synonymous with a start switch) and the other end side of the start switch rod is brought into contact with an actuating rod of a return valve (synonymous with a check valve) to supply hydraulic oil (Patent Document 1: Japanese Patent Application Laid-Open No. 2001-009630). In addition, a hydraulic crimping tool having the following structure has been proposed: a sliding release button for operating a release valve (synonymous with a check valve) via a rod is arranged near a power switch (synonymous with a start switch) having a switch handle (synonymous with a trigger rod) to restrict the operation of the switch handle, and hydraulic oil is supplied and released by operating the switch handle (Patent Document 2: Japanese Patent Application Laid-Open No. 2000-343448, Patent Document 3: Japanese Patent Application Laid-Open No. 2000-343452). In addition, a compression tool or a cutting tool is proposed, which is equipped with a reset device and a switch, the reset device having a control substrate, a servo motor, a cam and a rod that engages with an opener of the return valve (synonymous with the check valve) to delay the opening of the return valve (synonymous with the check valve), and the switch controls the servo motor in a manner such that if a drive button (synonymous with the start switch) is released, the rod is aligned with the position in which the return valve is kept in an open state, and if the drive button is driven, the rod is aligned with the position in which the return valve (synonymous with the check valve) is closed (Patent Document 4: Japanese Patent Gazette No. 2017-213671).

[0003] Prior art literature

[0004] Patent Literature

[0005] Patent Document 1: Japanese Patent Application Publication No. 2001-009630

[0006] Patent Document 2: Japanese Patent Application Publication No. 2000-343448

[0007] Patent Document 3: Japanese Patent Application Publication No. 2000-343452

[0008] Patent Document 4: Japanese Patent Application Publication No. 2017-213671 Summary of the invention

[0009] Problem that the invention aims to solve

[0010] The electric tools described in Patent Documents 1 to 3 are limited to pistol-shaped bodies due to the proximity of the trigger rod and the start switch, and the proximity of the trigger rod and the actuating rod of the one-way valve, and cannot be applied to a linear body. The electric tool described in Patent Document 4 is a complex structure in which a servo motor is specially provided for closing the one-way valve, which is large in scale and will waste component costs, making it difficult to achieve miniaturization.

[0011] Solutions for solving problems

[0012] The present invention has been made in view of the above circumstances, and an object of the present invention is to provide an electric power tool that can realize automatic reflow and has a compact structure with excellent workability.

[0013] As one embodiment, the above-mentioned problem is solved by the solution disclosed below.

[0014] The electric tool of the present invention is characterized in that it comprises: a main body, which is provided with a cylinder part; and a working attachment, which is connected to the main body and works by utilizing the hydraulic pressure of the cylinder part, wherein the main body has: an oil tank; a hydraulic pump, which delivers the working oil in the oil tank to the cylinder part; a motor, which drives the hydraulic pump; a secondary battery, which supplies power to the motor; a flow path part, which allows the working oil to flow; a trigger rod; a first connecting rod accessory, which connects the trigger rod and the start switch; and a second connecting rod accessory, which connects the trigger rod and the reflux switch. and a spring that applies force to the trigger rod in a direction to return the trigger rod, the flow path portion comprising: a boost flow path that is connected from the oil tank to the cylinder portion to transport the working oil; a return flow path that is connected from the cylinder portion to the oil tank to return the working oil; a one-way valve that opens and closes the return flow path; and a return pin that presses the one-way valve to open the return flow path, the trigger rod being configured to be arranged on the opposite side of the side on which the return switch is arranged relative to the axis passing through the cylinder portion.

[0015] According to this structure, by connecting the start switch and the trigger lever by the first connecting rod fitting and connecting the return switch and the trigger lever by the second connecting rod fitting, a simple structure and a straight-line main body can be achieved. Furthermore, by combining the start switch, the first connecting rod fitting, the trigger lever and the second connecting rod fitting, a series of actions from the boosting action to the return action can be performed by operating the trigger lever, and an electric tool with a small structure and excellent operability that can realize automatic return can be achieved.

[0016] Preferably, the first link fitting has: a first contact portion that contacts the start switch; a rod-shaped portion that is arranged along the axis; and a second contact portion that contacts the trigger lever, and the second link fitting has: a third contact portion that is locked to the reflux switch; an annular portion that is arranged in a direction intersecting the axis; and a support portion that is supported by the trigger lever. According to this structure, both the first link fitting and the second link fitting can be easily operated by operating the trigger lever alone, and can be a structure suitable for a linear body.

[0017] As an example, the main body has: a controller that controls the motor; and a switch that limits the range of motion of the trigger rod, the motor, the start switch, and the controller are sequentially arranged along the axis, and the switch is arranged close to the trigger rod. According to this structure, by providing a switch, it is possible to further improve the safety. And, as needed, it is possible to easily switch between the automatic reflux action and the holding action to perform the operation.

[0018] As an example, the flow path has a pressure limiting valve for limiting the pressure on the high-pressure side, and the pressure limiting valve is arranged at a position closer to the cylinder than the one-way valve. According to this structure, it is possible to avoid interference with the second connecting rod accessory and connect the pressure limiting valve at a position close to the cylinder in the return flow path, thereby achieving a reasonable flow path structure.

[0019] As an example, the electric tool is configured to have: a boost mode, in which the trigger lever is pressed in to turn on the start switch to deliver the working oil to the cylinder; a hold mode, in which the trigger lever is returned halfway, the start switch is turned off with the one-way valve closed, and the working oil delivered to the cylinder is maintained; and a reflux mode, in which the trigger lever is returned to an initial position, the one-way valve is opened, and the working oil is returned to the oil tank. According to this configuration, the automatic reflux action and the hold action can be switched only by the operation of the trigger lever.

[0020] Effects of the Invention

[0021] According to the present invention, a linear electric tool having a compact structure and excellent operability that can realize automatic reflow can be realized by a simple structure using the first link fitting and the second link fitting. BRIEF DESCRIPTION OF THE DRAWINGS

[0022] [ Figure 1 ] Figure 1 It is a schematic perspective view showing an example of an electric power tool according to an embodiment of the present invention.

[0023] [ Figure 2 ] Figure 2 A is Figure 1 A schematic front view of the power tool shown, Figure 2 B is Figure 1 A schematic right side view of the power tool shown, Figure 2 C is Figure 1 A schematic rear view of the power tool is shown. Figure 2 D is Figure 1 A schematic left side elevation view of the power tool is shown.

[0024] [ Figure 3 ] Figure 3 A is a schematic diagram of the internal structure of the main unit in boost mode as seen from the back. Figure 3 B is Figure 3 A is a schematic longitudinal cross-sectional view.

[0025] [ Figure 4 ] Figure 4 A is a schematic diagram of the internal structure of the main body when viewed from the back in the holding mode. Figure 4 B is Figure 4 A is a schematic longitudinal cross-sectional view.

[0026] [ Figure 5 ] Figure 5 A is a schematic diagram of the internal structure of the main unit in the reflow mode when viewed from the back. Figure 5 B is Figure 5 A is a schematic longitudinal cross-sectional view.

[0027] [ Figure 6 ] Figure 6 This is a schematic longitudinal sectional view of the main body as viewed from the left side.

[0028] [ Figure 7 ] Figure 7 yes Figure 6 The VII-VII line sectional view is a schematic cross-sectional view.

[0029] [ Figure 8 ] Figure 8 A is a schematic perspective view of the first link fitting of this embodiment. Figure 8 B is Figure 8 A schematic front view, Figure 8 C is Figure 8 A schematic top view, Figure 8 D is Figure 8 A schematic bottom view.

[0030] [ Fig. 9 ] Fig. 9 A is a schematic front view of the second link fitting of this embodiment. Fig. 9 B is Fig. 9A schematic top view, Fig. 9 C is Fig. 9 A is a schematic bottom view. Fig. 9 D is Fig. 9 A schematic side view.

[0031] [ Fig.10 ] Fig.10 A is a schematic perspective view of a state where the second link fitting of the present embodiment is assembled to the trigger lever. Fig.10 B is Fig.10 A schematic side view.

[0032] [ Fig.11 ] Fig.11 A is a schematic perspective view of a switching switch according to this embodiment. Fig.11 B is a schematic structural diagram showing the arrangement relationship between the switch and the trigger lever in the reflow mode of the present embodiment. Fig.11 C is a schematic structural diagram showing the arrangement relationship between the switch and the trigger lever in the holding mode of the present embodiment. DETAILED DESCRIPTION

[0033] Hereinafter, an embodiment of the present invention will be described in detail with reference to the accompanying drawings. This embodiment is an electric tool 1 including an electric crimping machine, an electric compressor, and an electric cutting machine. In addition, in all the drawings used to illustrate the embodiments, the same reference numerals are marked for components having the same functions, and repeated descriptions of components marked with the same reference numerals are sometimes omitted.

[0034] Figure 1 to Figure 7 1 is a schematic structural diagram showing an example of an electric tool 1 according to the present embodiment. The electric tool 1 comprises: a main body 2, which is provided with a cylinder 3; and an operating attachment 31, which is connected to the main body 2 and operates by utilizing the hydraulic pressure of the cylinder 3. In this example, a processing tool 31a of the operating attachment 31 is mounted on a piston 3a of the cylinder 3. The present embodiment is a cordless tool for an operator to use by hand on site, and is a multifunctional electric tool 1 for replacing the operating attachment 31. Figure 1 The working attachment 31 is an example of being used as an electric crimping machine, and the processing tool 31a is a mold. Here, in order to easily explain the positional relationship of each part of the electric tool 1, the directions are indicated by X, Y, and Z arrows in the figure. In addition, the electric tool 1 works normally regardless of which direction it is in.

[0035] Figure 2 A is a schematic front view of the electric tool 1. Figure 2 B is Figure 2 Right side view of A, Figure 2 C is Figure 2 The rear view of A. Figure 2 D is Figure 2A is a left side view of the main body 2. The main body 2 has a trigger lever 21, a reflux switch 22, and a changeover switch 28. The trigger lever 21 is arranged on the opposite side of the side where the reflux switch 22 is arranged with respect to the axis P1 passing through the length direction of the main body 2. The changeover switch 28 is arranged on the side where the trigger lever 21 is arranged with respect to the axis P1 passing through the length direction of the main body 2. The main body 2 has an adapter 8, and a secondary battery 9 is connected to the adapter 8 as a battery pack.

[0036] Figure 3 A is a schematic diagram of the internal structure of the main body 2 when viewed from the back in the boost mode. Figure 3 B is Figure 3 A is a schematic longitudinal sectional view. When the trigger lever 21 is pushed in and the start switch 2b is turned on, the pressure-increasing mode is set to deliver the hydraulic oil 4a to the cylinder 3. When the main body 2 is in the pressure-increasing mode, as an example, a compression terminal or a crimping sleeve is crimped or compressed.

[0037] Figure 4 A is a schematic diagram of the internal structure of the main body 2 when it is in the holding mode, as viewed from the back. Figure 4 B is Figure 4 A is a schematic longitudinal sectional view. After the compression operation and crimping operation are completed, the trigger rod 21 is returned to the middle, and the start switch 2b is turned off with the check valve 25 closed, and the holding mode is entered to hold the hydraulic oil 4a supplied to the cylinder 3. By putting the main body 2 in the holding mode, as an example, the crimping or compression operation can be repeated in a short time, and by holding the compression terminal or crimping sleeve, the operator can adjust the connection position with the wire.

[0038] Figure 5 A is a schematic internal structure diagram of the main body 2 in the reflow mode as viewed from the back side. Figure 5 B is Figure 5 A is a schematic longitudinal sectional view of the power tool 1. After a series of operations such as the compression operation and the crimping operation are completed, the trigger lever 21 is returned to the initial position, the one-way valve 25 is opened, and the return mode for returning the working oil 4a to the oil tank 4 is realized. The main body 2 is in the return mode, and the power tool 1 is in the initial state. In addition, as needed, the operator sometimes presses the return switch 22 to press the return pin 24, thereby pressing the one-way valve 25 to open the return flow path 5b, and the working oil 4a is returned to the oil tank 4.

[0039] Figure 6 This is a schematic longitudinal sectional view of the main body 2 as viewed from the left side. Figure 7 yes Figure 6The VII-VII line sectional view is a schematic cross-sectional view. The electric tool 1 has: a swash plate cam 6a, which is connected to the drive shaft 7a of the motor 7 and rotates; and a plurality of plungers 6b, which are arranged in the cylinder part 3 around the axis P1 passing through the drive shaft 7a and reciprocate while contacting the swash plate cam 6a. The oil tank 4 is arranged at a position connecting the cylinder part 3 and the hydraulic pump 6. The oil tank 4 is connected to the hydraulic pump 6 via the suction check valve 6d. In addition, the oil tank 4 is connected to the cylinder part 3 via the discharge check valve 6c.

[0040] The main body 2 has an oil tank 4, a hydraulic pump 6 that delivers the working oil 4a in the oil tank 4 to the cylinder 3, a motor 7 that drives the hydraulic pump 6, a secondary battery 9 that supplies power to the motor 7, a flow path 5 that allows the working oil 4a to flow, and a trigger rod 21 that operates the working attachment 31. In addition, the housing 2a of the main body 2 is provided with a first link fitting 11 that connects the trigger rod 21 and the start switch 2b, a second link fitting 12 that connects the trigger rod 21 and the return switch 22, and a spiral spring 23 that urges the trigger rod 21 in a direction to return the trigger rod 21.

[0041] The cylinder part 3 is provided with a piston 3a in a piston chamber 3b, and a coil spring 3c is provided in a manner aligned with the axis of the piston 3a and along the outer periphery of the piston 3a. The hydraulic pump 6 delivers the working oil 4a stored in the oil tank 4 to the cylinder part 3. In addition, the main body 2 has: a motor 7 connected to the hydraulic pump 6 and driving the hydraulic pump 6; and a controller 27 that controls the driving of the motor 7.

[0042] The flow path unit 5 is formed with a pressure-boosting flow path 5a, which is connected from the oil tank 4 to the cylinder unit 3 to deliver the working oil 4a, and a return flow path 5b, which is connected from the cylinder unit 3 to the oil tank 4 to return the working oil 4a. The return flow path 5b is provided with a check valve 25 on the path, and a return pin 24 that presses the check valve 25 to open the return flow path 5b is provided. In addition, the flow path unit 5 is connected with a pressure limiting valve 26 that limits the pressure on the high-pressure side on the path of the return flow path 5b, and the pressure limiting valve 26 is arranged at a position closer to the cylinder unit 3 than the check valve 25.

[0043] The main body 2 is provided with an adapter 8, and a secondary battery 9 for supplying power to the motor 7 and the controller 27 is connected to the adapter 8 in a detachable manner as a battery pack. As an example, the secondary battery 9 is a lithium-ion battery, a nickel-metal hydride battery, or other known secondary batteries. With this structure, an electric tool 1 with excellent portability is achieved. As an example, the hydraulic pump 6, the motor 7, the start switch 2b, the adapter 8, and the secondary battery 9 are configured to be arranged in sequence along the axis P1. The start switch 2b for energizing the motor 7 is arranged at a position between the motor 7 and the controller 27. According to this structure, it is possible to achieve a reasonable structure that divides the configuration of electrical components and the configuration of hydraulic components.

[0044] Figure 8 A is a schematic perspective view of the first link fitting 11. Figure 8 B is Figure 8 A schematic front view, Figure 8 C is Figure 8 A schematic top view, Figure 8 D is Figure 8 A is a schematic bottom view. The first link fitting 11 includes a first contact portion 11a that contacts the start switch 2b, a rod-shaped portion 11b that is arranged along the axis P1, and a second contact portion 11c that contacts the trigger lever 21. As an example, the first link fitting 11 is formed by bending a hard metal shaft.

[0045] Fig. 9 A is a schematic front view of the second link fitting 12. Fig. 9 B is Fig. 9 A schematic top view, Fig. 9 C is Fig. 9 A is a schematic bottom view. Fig. 9 D is Fig. 9 A is a schematic side view. The second link fitting 12 includes: a third contact portion 12a engaged with the return switch 22; an annular portion 12b disposed in a direction intersecting the axis P1; and a support portion 12c supported by the trigger lever 21. As an example, the second link fitting 12 is formed by stamping a hard metal plate.

[0046] Fig.10 A is a schematic perspective view of a state where the second link fitting 12 is assembled to the trigger lever 21. Fig.10 B is Fig.10A is a schematic side view of the trigger lever 21. The trigger lever 21 has a fourth contact portion 21a formed on one end side in the longitudinal direction, which contacts the second contact portion 11c of the first link fitting 11. The trigger lever 21 has a spring 23 disposed near the center in the longitudinal direction, and a convex receiving portion 21b is provided on the side opposite to the fourth contact portion 21a with respect to the spring 23. The through hole of the support portion 12c of the second link fitting 12 is engaged with the receiving portion 21b of the trigger lever 21 in a manner that the second link fitting 12 can rotate.

[0047] Fig.11 A is a schematic perspective view of the changeover switch 28 . Fig.11 B is a schematic structural diagram showing the arrangement relationship between the switch 28 and the trigger lever 21 in the reflow mode. Fig.11 C is a schematic structural diagram showing the configuration relationship between the switch 28 and the trigger lever 21 in the hold mode. The trigger lever 21 is pivotally supported by a support pin 29 mounted on the housing 2a of the main body 2. The switch 28 is a plate-like body with an elliptical cross-section, and is mounted on the housing 2a in a direction intersecting the axis P1. The switch 28 has a second limiting surface 28a formed on one end side in the short side direction, which contacts the first limiting surface 21c of the trigger lever 21. In addition, the switch 28 has a fourth limiting surface 28b formed above one end side in the short side direction, which contacts the third limiting surface 21d of the trigger lever 21.

[0048] The switch 28 is disposed close to the trigger rod 21 to limit the range of motion of the trigger rod 21. Fig.11 As shown in B, if the switch 28 is pressed, the trigger rod 21 is not in contact with the switch 28, and the range of motion of the trigger rod 21 is not limited. Therefore, automatic reflow can be achieved. Fig.11 As shown in FIG. 3C, if the toggle switch 28 is pulled out, the trigger rod 21 is returned to the middle and becomes in the holding mode, and the trigger rod 21 is in contact with the toggle switch 28, and the range of motion of the trigger rod 21 is limited. Thus, the holding mode is maintained. Here, if the toggle switch 28 is pressed in halfway, the toggle switch 28 limits the range of motion of the trigger rod 21, and the trigger rod 21 can be prevented from moving from the initial position. By providing the toggle switch 28, a structure that further improves the safety of the operation can be achieved. Moreover, the automatic reflux action and the holding action can be easily switched to perform the operation as needed.

[0049] In the above example, the push-in type changeover switch 28 is described, but the present invention is not limited to this example. For example, a slide type changeover switch or a dial type changeover switch can be provided instead of the push-in type. In the above example, the second link fitting 12 has a structure with an annular portion 12b, but the present invention is not limited to this example. For example, a second link fitting having an arc-shaped portion or a circular arc-shaped portion can be provided instead of the annular portion 12b.

[0050] In the above example, the electric tool 1 having a linear body is described, but the present invention is not limited to this example. This structure can be applied to a portable electric tool. The present invention is not limited to the above-described embodiment, and various changes can be made without departing from the scope of the present invention.

Claims

1. An electric tool, characterized in that: The electric tool comprises: a main body, which is provided with a cylinder; and a working attachment, which is connected to the main body and operates by utilizing the hydraulic pressure of the cylinder. The main body comprises: an oil tank; a hydraulic pump that delivers the working oil in the oil tank to the cylinder; a motor that drives the hydraulic pump; a secondary battery that supplies power to the motor; a flow path that allows the working oil to flow; a trigger rod; a first connecting rod accessory that connects the trigger rod and a start switch; a second connecting rod accessory that connects the trigger rod and a reflux switch; and a spring that applies force to the trigger rod in a direction that causes the trigger rod to return. The flow path unit includes: a pressure-increasing flow path that communicates from the oil tank to the cylinder unit to deliver the working oil; a return flow path that communicates from the cylinder unit to the oil tank to return the working oil; a check valve that opens and closes the return flow path; and a return pin that presses the check valve to open the return flow path. The trigger lever is configured to be arranged on the opposite side of the axis passing through the cylinder portion from the side on which the backflow switch is arranged.

2. The electric tool according to claim 1, characterized in that: The first connecting rod accessory comprises: a first contact portion that contacts the start switch; a rod-shaped portion that is arranged along the axis; and a second contact portion that contacts the trigger lever. The second link fitting includes: a third contact portion engaged with the reflux switch; an annular portion disposed in a direction intersecting the axis; and a support portion supported by the trigger lever.

3. The electric tool according to claim 1, characterized in that: The main body comprises: a controller for controlling the motor; and a switch for limiting the range of motion of the trigger rod. The motor, the start switch and the controller are sequentially arranged along the axis. The switching switch is arranged close to the trigger rod.

4. The electric tool according to claim 2, characterized in that: The main body comprises: a controller for controlling the motor; and a switch for limiting the range of motion of the trigger rod. The motor, the start switch and the controller are sequentially arranged along the axis. The switching switch is arranged close to the trigger rod.

5. The electric tool according to claim 1, characterized in that: The flow path portion has a pressure limiting valve that limits the pressure on the high-pressure side. The pressure limiting valve is arranged at a position closer to the cylinder portion than the check valve.

6. The electric tool according to claim 2, characterized in that: The flow path portion has a pressure limiting valve that limits the pressure on the high-pressure side. The pressure limiting valve is arranged at a position closer to the cylinder portion than the check valve.

7. The electric tool according to claim 1, characterized in that: The electric tool has: a boost mode, in which the trigger rod is pressed in to turn on the start switch, and the working oil is delivered to the cylinder; a holding mode, in which the trigger rod is returned to the middle, and the start switch is disconnected when the one-way valve is closed, so that the working oil delivered to the cylinder is maintained; and a reflux mode, in which the trigger rod is returned to the initial position, the one-way valve is opened, and the working oil is returned to the oil tank.

8. The electric tool according to claim 2, characterized in that: The electric tool has: a boost mode, in which the trigger rod is pressed in to turn on the start switch, and the working oil is delivered to the cylinder; a holding mode, in which the trigger rod is returned to the middle, and the start switch is disconnected when the one-way valve is closed, so that the working oil delivered to the cylinder is maintained; and a reflux mode, in which the trigger rod is returned to the initial position, the one-way valve is opened, and the working oil is returned to the oil tank.

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