Electric implement with operation stick

Abstract

To facilitate safety measure control, etc. for electrically detecting a posture of a working part on an operation stick tip side in an electric implement with an operation stick for transmitting power of an electric motor provided on a base end side of the operation stick to the working part on an operation stick tip side through a transmission shaft passing inside the operation stick.SOLUTION: An electric implement with an operation stick transmits power of an electric motor provided on a base end side of an operation stick to a working part provided on a tip side of the operation stick through a transmission shaft passing inside the operation stick. The working part is pivotally supported at the tip part of the operation stick to enable a cutting part to take a storage posture along the operation stick. A detection switch for detecting the storage posture of the working part is provided at the tip of the operation stick. A control part for controlling the drive of the electric motor is provided at the base end part of the operation stick. A lead wire for transmitting a detection signal of the detection switch to the control part is provided inside the operation stick. When the detection switch detects the storage posture of the working part, the control part prohibits the operation of the electric motor.SELECTED DRAWING: Figure 1

Description

[Technical field]

[0001] The present invention relates to an electric working machine with an operating stick. [Background technology]

[0002] Working machines such as brush cutters and hedge trimmers are equipped with an operating rod that extends in one axial direction, with a working unit having a cutting blade and the like disposed at the tip end of the operating rod, and an operating unit such as an operating handle provided at the base end (the side opposite to the tip end) of the operating rod. In recent years, electric-powered working machines with such operating rods have become popular because they produce less noise and vibration than engine-powered machines.

[0003] Conventionally, in an electric work machine with a control stick (electric work machine with a control stick), a heavy battery is mounted on the base end of the control stick or worn by the operator, and an electric motor that drives the working part is mounted on the tip end of the control stick, with the power supply cable connecting the electric motor and the battery routed through the inside of the control stick (see Patent Document 1 below). [Prior art documents] [Patent documents]

[0004] [Patent Document 1] JP 2016-202122 A Summary of the Invention [Problem to be solved by the invention]

[0005] In the conventional electric working machine with a control stick described above, the weight of the tip of the control stick is large because the electric motor is located at the tip of the control stick, and this causes a problem that the workload on the worker's arms increases when working while swinging the working part from side to side, such as when cutting grass. One possible solution to this problem is to provide an electric motor together with a battery at the base end of the control stick, and transmit power to the working part at the tip of the control stick via a transmission shaft that passes through the inside of the control stick.

[0006] However, if the power of the electric motor mounted on the base end of the operating stick is transmitted to the working unit at the tip end of the operating stick via a transmission shaft passing through the inside of the operating stick, the electrical components of the electric work machine with the operating stick are concentrated on the base end side of the operating stick, which creates the problem that it becomes difficult to perform safety control that electrically detects the posture of the working unit mounted on the tip end of the operating stick or the operation of the front handle mounted on the operating stick to stop the electric motor.

[0007] The present invention has been proposed to address such problems. That is, the objective of the present invention is to facilitate safety control that electrically detects the attitude of the working part at the tip of the operating stick in an electric working machine with an operating stick, in which the power of an electric motor provided on the base end side of the operating stick is transmitted to the working part at the tip of the operating stick via a transmission shaft that passes through the inside of the operating stick. [Means for solving the problem]

[0008] In order to solve such problems, the present invention has the following configuration. An electric work machine with an operating stick in which the power of an electric motor provided on the base end side of the operating stick is transmitted to a working unit provided on the tip side of the operating stick via a transmission shaft passing through the inside of the operating stick, the working unit is journalled to the tip of the operating stick so that it can be placed in a stored position with a blade unit aligned with the operating stick, a detection switch is provided at the tip of the operating stick for detecting the stored position, a control unit is provided at the base end of the operating stick for controlling the drive of the electric motor, a lead wire is provided inside the operating stick for transmitting a detection signal from the detection switch to the control unit, and the control unit prohibits operation of the electric motor when the detection switch detects the stored position of the working unit. Effect of the Invention

[0009] According to the present invention, which has such characteristics, in an electric work machine with a control stick, in which the power of an electric motor provided on the base end of the control stick is transmitted to the working part on the tip side of the control stick via a transmission shaft passing through the inside of the control stick, it becomes easier to perform safety control such as electrically detecting the posture of the working part on the tip side of the control stick. [Brief description of the drawings]

[0010] [Figure 1] 1 is an explanatory diagram showing the overall configuration (working posture) of an electric working machine with a control stick according to an embodiment of the present invention; [Diagram 2] 1 is an explanatory diagram showing the overall configuration (storage position) of an electric working machine with an operating stick according to an embodiment of the present invention; [Diagram 3] FIG. 1 is an explanatory diagram showing a schematic configuration of a power unit of an electric working machine with a control stick according to an embodiment of the present invention. [Figure 4] FIG. 2 is an explanatory diagram showing the structure of the tip side of the operating stick (without the cover member) in the electric working machine with the operating stick according to the embodiment of the present invention. [Diagram 5] FIG. 2 is an explanatory diagram showing the structure of the tip side of the operating stick (with a cover member) in the electric working machine with an operating stick according to the embodiment of the present invention. [Figure 6] FIG. 2 is an explanatory diagram showing an example of a wiring state of lead wires in an electric operating machine with a control stick according to an embodiment of the present invention. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0011] Hereinafter, an embodiment of the present invention will be described with reference to the drawings. In the following description, the same reference numerals in different drawings indicate parts having the same function, and duplicated descriptions in each drawing will be omitted as appropriate.

[0012] 1 and 2, an electric work machine with a control stick (hereinafter, work machine) 1 includes a control stick 2, a power unit 3 provided on the base end side of the control stick 2, and a working unit 4 provided on the tip end side of the control stick 2. The X direction of the illustrated arrow indicates the longitudinal direction of the control stick 2, and the Y and Z directions of the illustrated arrow indicate two directions that are perpendicular to the X direction and perpendicular to each other.

[0013] The control stick 2 is a hollow tubular member extending in one axial direction (the X direction in the figure), and a rear handle 7 and a front handle 8 are provided on the outer periphery of the control stick 2. The rear handle 7 is provided on the base end side of the control stick 2 and is the part that is held by one of the operator's hands, and an operation panel 7A and an operation lever 7B for starting and stopping the power unit 3 are provided nearby.

[0014] The front handle 8 is provided at an intermediate position of the control stick 2, and is the part that is held by the operator's other hand. If necessary, the front handle 8 can also be provided with an operating mechanism for starting and stopping the operating unit 3 and a detection switch for safety purposes, which will be described later (see the example shown in FIG. 6). The position of the front handle 8 is determined at a position where, when one hand of the operator is holding the rear handle 7, the other hand of the operator can easily hold the front handle 8. Therefore, in the case of a work machine 1 in which the length of the control stick 2 is short, the position of the front handle 8 is close to the tip of the control stick 2.

[0015] 3 shows a schematic configuration of the power unit 3. The power unit 3 has a power case 3A on the base end side of the operating stick 2, and an internal housing 3A1 to which the base end side of the operating stick 2 is fixed is provided inside the power case 3A. An electric motor 3B and a control unit 3C are provided inside the internal housing 3A1. A replaceable battery 3D for supplying power is provided outside the internal housing 3A1. The electric motor 3B, the control unit 3C, and the battery 3D are connected to each other by wiring (not shown), and the electric motor 3B is controlled by an output signal from the control unit 3C, and the battery 3D supplies power to the electric motor 3B and the control unit 3C.

[0016] The working unit 4 is pivotally supported on the tip of the operating stick 2 and can rotate around the Y-axis with respect to the tip of the operating stick 2 between the working posture shown in FIG. 1 and the stored posture shown in FIG. 2. In the illustrated example, the working unit 4 has a blade 4A for performing brush cutting work and the like. In the working posture shown in FIG. 1, the blade 4A is arranged along an extension line of the operating stick 2 or along a line at a predetermined angle with respect to the longitudinal direction of the operating stick 2. In addition, the stored posture shown in FIG. 2 is a posture in which the blade 4A is aligned with the operating stick 2 and the tip of the blade 4A faces the base end side of the operating stick 2. In addition, the stored posture is a posture in which the longitudinal direction of the blade 4 is within a set angle range with respect to the longitudinal axis (X-axis in the figure) with the tip of the blade 4A facing the base end side of the operating stick 2.

[0017] The power transmission system of the working machine 1 will be described. As shown in Fig. 3, a transmission shaft 5 is arranged inside the operating stick 2 along one axial direction. The transmission shaft 5 is supported by a plurality of shaft support members 6 provided inside the operating stick 2. The working machine 1 uses an electric motor 3B provided in the power unit 3 as a drive source, and the power of the electric motor 3B is transmitted to the working unit 4 provided on the tip side of the operating stick 2 via the transmission shaft 5 passing through the inside of the operating stick 2. The connection between the electric motor 3B and the transmission shaft 5 is such that the output shaft of the electric motor 3B is directly connected to the base end side of the transmission shaft 5.

[0018] 4, the tip side of the transmission shaft 5 is connected to an input gear in a fixed gear case 2A provided on the tip side of the operating rod 2, and an output gear in the fixed gear case 2A is connected to an input gear in a movable gear case 4B on the working unit 4 side. The movable gear case 4B is equipped with a transmission mechanism that converts the rotation of the input gear into reciprocating motion, and the reciprocating blade of the cutting unit 4A is driven by the converted reciprocating motion.

[0019] Inside the operating stick 2, lead wires 9 are arranged along the longitudinal direction of the transmission shaft 5. The operating stick 2 has a wiring space 2B for arranging the lead wires 9 around the transmission shaft 5. The wiring space 2B is formed passing through multiple shaft support members 6 and is configured so that the rotation of the transmission shaft 5 inside the operating stick 2 does not interfere with the lead wires 9. Specifically, when there are multiple lead wires 9, configurations can be adopted in which these are bundled together with a protective tube or the like, or the spaces formed between the shaft support members 6 and the inner surface of the operating stick 2 are linearly aligned and the lead wires 9 are passed through therein.

[0020] The operating rod 2 is provided with a plurality of pull-out holes 20 for pulling out a connection terminal 10 on one end of the lead wire 9 and a connection terminal 11 on the other end to the outside of the operating rod 2. Here, the connection terminal 10 is connected to a connection terminal 12A of a wiring 12 for connecting to a control unit 3C inside a power case 3A of the power unit 3, as shown in Fig. 3, and the connection terminal 11 is connected to a connection terminal 14A of a wiring 14 for connecting to a detection switch 13 provided on the tip side of the operating rod 2, as shown in Fig. 4.

[0021] 3 and 4, a lead hole 20 for drawing out the connection terminal 10 on one end of the lead wire 9 and the connection terminal 11 on the other end of the lead wire 9 to the outside of the operating stick 2 is provided in communication with the wiring space 2B. The lead hole 20 can be provided at any position near the electrical component that needs to be connected to the lead wire 9. For example, when a detection switch or the like is provided on the front handle 8 attached to the intermediate position of the operating stick 2, the lead hole 20 is formed in the intermediate position of the operating stick 2 and the lead wire 9 is drawn out from there.

[0022] In the illustrated example, a grommet 20G is attached to the pull-out hole 20 to protect the lead wire 9. The size of the connection terminals 10, 11 of the lead wire 9 is set to a size that allows them to pass through the inner diameter d of the pull-out hole 20 when the grommet 20G is removed. In other words, the inner diameter d of the pull-out hole 20 is set to a size that allows the connection terminals 10, 11 of the lead wire 9 to pass through. In this way, by adjusting the size of the connection terminals 10, 11 and the inner diameter of the pull-out hole 20, smooth wiring of the lead wire 9 to the operating rod 2 is possible.

[0023] The lead wire 9 (pullout lead wire 9A) pulled out from the operating stick 2 through the pullout hole 20 is covered with a cover member so as not to be exposed to the outside. At the base end side of the operating stick 2, the power case 3A and the rear handle 7 serve as cover members for the pullout lead wire 9A pulled out from the pullout hole 20.

[0024] 5, at the tip side of the operating rod 2, the lead wire 9A drawn out from the lead hole 20 is covered with a cover member 21. In addition, the connection terminal 11 of the lead wire 9A, the connection terminal 14A and the wiring 14 connected thereto, and the detection switch 13 are covered with another cover member 22.

[0025] The working unit 4 is provided with a position-changing handle 4C integral with the movable gear case 4B. By operating the position-changing handle 4C while performing the release operation of the lock release lever 4D, the entire working unit 4 can be rotated around the axis O (see FIG. 4) to change its position. In the working position shown in FIG. 1, the longitudinal direction of the blade 4A can be changed within a predetermined angle range from the extension line of the operating rod 2. At this time, the position of the working unit 4 is fixed by engaging the engaging claw 4D1 of the lock release lever 4D with a predetermined position of the engaged claw 4E provided around the axis O.

[0026] The detection switch 13 is disposed on the outside of the fixed gear case 2A at the tip side of the operating stick 2, and detects the posture state of the working unit 4. In the illustrated example, the detection switch 13 detects the stored posture of the working unit 4 and transmits a detection signal to the control unit 3C via the lead wire 9. When the detection switch 13 detects the stored posture of the working unit 4, the control unit 3C outputs a control signal to inhibit the operation of the electric motor 3B. Because the detection switch 13 is attached to the tip (fixed side) of the operating stick 2, the lead wire 9 (drawing lead wire 9A) connected to the detection switch 13 does not affect the rotation of the working unit 4 even when the working unit 4 rotates to change its posture.

[0027] On the other hand, the working unit 4 is provided with a switch operation mechanism that operates the detection switch 13. In the example shown in Fig. 4, the switch operation mechanism is a mechanism that operates the detection switch 13 when the rotation of the working unit 4 around the axis O enters a set range, and the switch operation is performed by a part of the working unit 4 or a member that rotates integrally with the working unit. Specifically, the working unit 4 is provided with an operation member 4F that rotates integrally with the movable gear case 4B around the axis O, and the operation member 4F performs the switch operation of the detection switch 13 directly or via a movable member. The mechanism that rotates the operation member 4F integrally with the movable gear case 4B serves as the switch operation mechanism.

[0028] The combination of the detection switch 13 and the switch operation mechanism is not limited to the above-mentioned example. The detection switch 13 can be any of various switches (or sensors), such as a microswitch that outputs a detection signal by mechanical operation, a proximity sensor that magnetically detects the position change of the working unit 4 without contact, or a rotary position sensor or rotary volume that detects the position change of the working unit 4 by a change in electrical resistance. In addition, the working unit 4 can be equipped with various switch operation mechanisms so that the above-mentioned various switches (or sensors) are activated by the rotation of the working unit 4.

[0029] The detection switch 13, which is responsible for the safety measures of the working machine 1, is not limited to the one provided at the tip of the operating rod 2 as described above. As shown in FIG. 6, when the detection switch 13 (13A, 13B) is provided on the rear handle 7 and the front handle 8, the control unit 3C does not allow the driving of the electric motor (not shown) even if the operating lever 7B is operated unless both the detection switch 13A provided on the rear handle 7 and the detection switch 13B provided on the front handle 8 are simultaneously operated. According to this, the working unit 4 cannot be driven unless the operator is properly holding the handle of the working machine 1 with both hands, so that dangerous work such as one-handed work can be eliminated. In addition, it is possible to provide multiple detection switches and allow the control unit 3C to drive the electric motor only when safety is detected by all the detection switches, thereby enabling more reliable execution of safety measure control.

[0030] At this time, detection switch 13A provided on rear handle 7 and detection switch 13B provided on front handle 8 are disposed on the outside of joystick 2, so that one end of lead wire 9 connecting detection switch 13A and control unit 3C is drawn out from a lead hole provided in joystick 2 near the rear handle 7 and connected to detection switch 13A, and one end of lead wire 9 connecting detection switch 13B and control unit 3C is drawn out from a lead hole provided in joystick 2 near the front handle 8 and connected to detection switch 13B. Then, each lead wire 9 passes through joystick 2 and has the other end drawn out from a lead hole on the base end side of joystick 2 and connected to control unit 3C of power unit 3.

[0031] In this type of work machine 1, the power of the electric motor 3B provided on the base end side of the operating stick 2 is transmitted to the working part 4 provided on the tip side of the operating stick 2 via the transmission shaft 5 passing through the inside of the operating stick 2, thereby making it possible to reduce the weight of the tip part of the operating stick 2 even though it is an electric work machine. This makes it possible to reduce the burden of work that is performed while swinging the tip side of the operating stick 2, such as weeding work.

[0032] In the work machine 1, the working unit 4 is journaled on the tip of the control stick 2 so that it can be placed in a stored position with the blade 4A aligned with the control stick 2, a detection switch 13 for detecting the stored position is provided at the tip of the control stick 2, a control unit 3C for controlling the drive of the electric motor 3B is provided at the base end of the control stick 2, a lead wire 9 for transmitting a detection signal of the detection switch 13 to the control unit 3C is provided inside the control stick 2, and the control unit 3C prohibits the operation of the electric motor 3B when the detection switch 13 detects the stored position of the working unit 4. This enables safety control when the working unit 4 is in the stored position, and makes it possible to prevent a situation in which the blade 4A of the working unit 4 starts to move due to erroneous operation when the working unit 4 is in the stored position.

[0033] More specifically, the working unit 4 is provided with a switch operation mechanism that operates the detection switch 13 when the rotation of the working unit 4 around the axis O enters a set range, and the switch operation mechanism is performed by a part of the working unit 4 or a member (operation member 4F) that rotates integrally with the working unit 4. With this, by fixing the detection switch 13 side to the tip of the operating rod 2, the working unit 4 can be rotated to obtain the stored position without affecting the wiring of the lead wire 9 connected to the detection switch 13, and since the detection switch 13 is operated by a member that rotates integrally with the working unit 4, the stored position of the working unit 4 can be detected with a simple configuration.

[0034] Detection switch 13 is attached to the outside of fixed gear case 2A provided at the tip of operating stick 2, and connection terminal 11 of lead wire 9 is pulled out to the outside of operating stick 2 and connected to detection switch 13. This allows detection switch 13 to be installed without affecting the internal configuration of fixed gear case 2A provided at the tip of operating stick 2, and it can be connected to lead wire 9 arranged inside operating stick 2. At this time, a cover member that covers detection switch 13 is provided on the outside of the tip of operating stick 2, so that detection switch 13 does not come into contact with grass or the like during work, causing problems such as damage to detection switch 13 or disconnection of detection switch 13 from lead wire 9.

[0035] Although the embodiments of the present invention have been described in detail above with reference to the drawings, the specific configuration is not limited to these embodiments, and the present invention includes design changes and the like that do not deviate from the gist of the present invention. In addition, the above-mentioned embodiments can be combined by utilizing each other's technologies as long as there are no particular contradictions or problems in the purpose, configuration, etc. [Explanation of symbols]

[0036] 1: Electric work machine with operating stick (work machine), 2: Operating rod, 2A: Fixed gear case, 2B: Wiring space, 3: Power unit, 3A: Power case, 3A1: Internal housing, 3B: Electric motor, 3C: Control unit, 3D: Battery, 4: Working part, 4A: Blade part, 4B: Movable gear case, 4C: Posture change handle, 4D: unlock lever, 4D1: engaging claw, 4E: engaged claw, 4F: Operating member (switch operating mechanism), 5: Transmission shaft, 6: Shaft support member, 7: Rear handle, 7A: Operation panel, 7B: Operation lever, 8: Front handle, 9: Lead wire, 9A: Pull-out lead wire, 10, 11, 12A, 14A: Connection terminal, 12, 14: Wiring, 13, 13A, 13B: Detection switch, 20: Pull-out hole, 20G: Grommet, 21, 22: Cover member, O: Shaft

Claims

1. In an electric operating machine with an operating rod, the power of an electric motor provided on the base end side of the operating rod is transmitted to a working unit provided on the tip side of the operating rod via a transmission shaft passing through the inside of the operating rod, The working unit is pivotally supported on the tip of the operating rod so that the working unit can be placed in a storage position with the blade unit aligned with the operating rod, A detection switch for detecting the stored position is provided at the tip of the operation stick, A control unit that controls the driving of the electric motor is provided at a base end of the operating rod, A lead wire is provided inside the operation rod to transmit a detection signal of the detection switch to the control unit, The control unit inhibits operation of the electric motor when the detection switch detects that the working unit is in a stored position.

2. 2. The electric work machine with a control rod according to claim 1, wherein the working unit is provided with a switch operating mechanism that operates the detection switch when rotation of the working unit about its axis enters a set range.

3. 3. The electric working machine with an operating rod according to claim 2, wherein the switch operation mechanism is operated by a part of the working unit or a member that rotates integrally with the working unit.

4. 3. The electric working machine with an operating rod according to claim 2, wherein the detection switch is a proximity sensor, and the switch operation mechanism is operated by the approach of a part of the working unit or a member which rotates integrally with the working unit.

5. 2. An electric work machine with an operating rod as described in claim 1, wherein the detection switch is attached to the outside of a fixed gear case provided at the tip of the operating rod, and a connection terminal of the lead wire is pulled out to the outside of the operating rod and connected to the detection switch.

6. On the outside of the tip of the operating stick, 7. The electric operating machine with an operating rod according to claim 6, further comprising a cover member for covering the detection switch.

7. In addition to the detection switch, a plurality of detection switches are provided, 2. The electric operating machine with a control stick according to claim 1, wherein the control unit allows the operation of the electric motor only when safety is detected by all of the detection switches.

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