JP7718108B2 - power tools - Google Patents

Description

The present invention relates to a power tool.

At construction sites, for example, after concrete has been poured into a mold made of plates known as concrete panels, nail removal may be required when separating the panels from the frame. In such cases, mechanized, power-driven nail pullers, such as air-operated, hydraulic-operated, or electric-operated, are sometimes used. Conventional nail pullers used in such situations generally have a threaded hook that catches the nail, and are designed to move the hook up and down by transmitting rotation from a motor to pull out the nail (see, for example, Patent Documents 1 and 2).

Japanese Utility Model Application Publication No. 5-5376 Japanese Patent Application Publication No. 11-48161

However, in reality, when using a nail puller to remove nails, it is not always possible to hook the nail head and pull it out smoothly; it is often necessary to use force, such as driving a crowbar next to the embedded nail and slightly pulling it out, or inserting the tip of the crowbar between the nailed board (such as a concrete panel) and the frame (such as a batten) and then hitting it hard with a hammer to separate them. Taking these circumstances into consideration, it would be convenient if a nail puller was designed with these situations in mind.

The present invention aims to provide a power tool with a structure that is more suitable for actual work such as pulling nails on-site.

One aspect of the present invention is a power tool used for work such as nail removal,
a main body;
an engaging member provided on the main body portion side and having an engaging portion that engages with a part of a work object;
a sliding member that moves in and out of the main body portion to move a part of the sliding member toward and away from the engaging member;
a drive source for operating the sliding member;
It is equipped with
This is a power tool in which a tapered pointed portion is formed on a part of the sliding member.

With a power tool like the one described above, the tapered pointed portion formed on part of the sliding member can be used to insert the sliding member, for example, into the gap between a board and a frame, or between a board and a nail head that is barely floating. Operating the sliding member in this inserted state makes it possible to separate the board and the frame, or to remove nails that are difficult to remove, improving the ease and efficiency of work.

In the above-described power tool, the pointed portion may have a tapered shape that faces away from the drive shaft that passes through the sliding member and extends in the sliding direction of the sliding member.

In the above-mentioned power tool, the pointed portion may have a tapered shape that faces in a direction perpendicular to the drive shaft.

In the above-described power tool, the pointed portion may be formed in a shape such that its tip is positioned outside the engaging portion of the engaging member relative to the drive shaft.

In the above-mentioned power tool, the pointed portion may be formed larger than the engaging member.

In the above-described power tool, the pointed portion may have a shape in which its outline is laid out outside the outline of the engaging member.

In the above-mentioned power tool, multiple pointed portions may be formed, and these pointed portions may be spaced apart so that the engaging portion can fit within them.

In the above-described power tool, the multiple pointed portions may be formed symmetrically about a plane including the drive shaft.

In the above-mentioned power tool, the pointed portion may be formed on a detachable attachment that forms part of the slider.

In the above-described power tool, the attachment may have a striking portion formed on the side opposite the pointed portion.

In the above-described power tool, the striking portion may be formed in a shape that protrudes toward the side opposite the pointed portion.

In the above-mentioned power tools, the attachment may be made of metal.

In the above-mentioned power tool, the attachment may be rotatable around the drive shaft.

The power tool of the present invention can be designed to be more suitable for actual work such as pulling out nails on-site.

FIG. 1 is a perspective view showing a state in which a rechargeable nail puller, which is an example of a power tool, is placed. FIG. 10 is a front view of the cordless nail puller in a position where the hook member faces directly downward (in use). FIG. 3 is a right side view of the rechargeable nail puller shown in FIG. 2 . FIG. 4 is a top view of the rechargeable nail puller shown in FIG. 3 . FIG. 4 is a view of the rechargeable nail puller shown in FIG. 3 as seen from below. FIG. 6 is a cross-sectional view of the rechargeable nail puller taken along line VI-VI in FIG. 4 . 6B is a cross-sectional view of the cordless nail puller in the same cross section as FIG. 6A, with the slider slid. FIG. FIG. 1 is an oblique view of a cordless nail puller with the tip of the slider against a concrete panel. 7B is an enlarged view of the periphery of the tip of the slider in FIG. 7A. FIG. FIG. 7B is a perspective view of the cordless nail puller with the slider slid to the position shown in FIG. 7A. 8B is an enlarged view of the hook member and its surroundings in FIG. 8A. FIG. FIG. 2 is a diagram showing the internal configuration of the mechanism, such as the hook member and slider, as viewed from the front. 9B is a cross-sectional view of the hook member, slider, ball screw, etc. taken along line IXB-IXB in FIG. 9A. FIG. 10 is a side view of the hook member, slider, ball screw, etc., with the slide member slid partway with the hook hooked on the nail. FIG. 10B is a longitudinal cross-sectional view of the hook member, slider, ball screw, etc. shown in FIG. 10A. 10 is a perspective view of the hook member, slider, ball screw, etc., seen from below in a state where the slider has been slid partway with the hook hooked on the nail. FIG. FIG. 12 is a perspective view of the hook member, slider, ball screw, etc. in FIG. 11 (excluding the cover around the ball screw). FIG. 13 is a perspective view showing a part of the hook member, slider, ball screw, etc. shown in FIG. 12 . FIG. 14 is a perspective view showing a hook member and a main frame among the members shown in FIG. 13 . FIG. 14 is a perspective view showing a slider and a ball screw among the members shown in FIG. 13 . 1A is a diagram illustrating a comparison between a rechargeable nail puller according to an embodiment of the present invention and a conventional rechargeable nail puller, in order to explain miniaturization, which is one of the advantages of the present invention. FIG. 1A and 1B are diagrams illustrating the rechargeable nail puller in a state before the slider is slid and the rechargeable nail puller in a state after the slider is slid, which are used to explain the miniaturization that is one of the advantages of the present invention. FIG. 10 is a front view of the hook member, slider, etc. of a conventional nail puller with the hook hooked on a nail driven at an angle. FIG. 17B is a cross-sectional view of a hook member, a slider, etc., taken along line XVIIB-XVIIB in FIG. 17A of the conventional nail puller. FIG. 10 is a perspective view showing a hook member, a slider, etc., in a state where the hook is hooked on a nail that has been driven obliquely into the nail puller of the related art. 1 is a front view of the hook member, slider, etc. of a conventional nail puller in a state where the slider has been slid to remove a nail that has been driven obliquely. 18B is a cross-sectional view of a hook member, a slider, etc., taken along line XVIIIB-XVIIIB in FIG. 18A of the conventional nail puller. FIG. 10 is a longitudinal cross-sectional view illustrating a hook member in which a hook portion is disposed at a position offset from a drive shaft. FIG. 10 is a vertical cross-sectional view illustrating how a nail is pulled out by a hook member having a hook portion disposed at a position offset from the drive shaft. FIG. 1 is a perspective view showing the cordless nail puller without the cover, with the tip of the slider against a concrete panel. FIG. 20B is a perspective view of the cordless nail puller with the slider slid to the position shown in FIG. 20A . This is a perspective view showing the cordless nail puller with the hook turned around and the tip of the slider facing the concrete panel. FIG. 21B is a perspective view of the cordless nail puller with the slider slid to the position shown in FIG. 21A . FIG. 1 is a perspective view of a rechargeable nail puller capable of changing the direction of the hook, viewed from the tip of the slider. FIG. 22B is a perspective view showing the state in which the orientation of the hook in the rechargeable nail puller shown in FIG. 22A is changed. FIG. 10 is a right side view showing the cordless nail puller with the tip of the slider against a concrete panel. FIG. 23B is a vertical cross-sectional view of the rechargeable nail puller shown in FIG. 23A. FIG. 23B is a right side view showing the cordless nail puller with the slider slid to the position shown in FIG. 23A . FIG. 24B is a vertical cross-sectional view of the rechargeable nail puller shown in FIG. 24A. FIG. 2 is a longitudinal cross-sectional view of the cordless nail puller as viewed from the front. This figure shows how the pointed part of the attachment is inserted between a concrete panel (plate material) and a crosspiece (frame material) and the part to be struck is struck with a hammer. This is an enlarged view of the attachment portion of the rechargeable nail puller with the pointed portion inserted between a concrete panel (board material) and a crosspiece (frame material). FIG. 1 is an enlarged longitudinal cross-sectional view showing the attachment portion of the rechargeable nail puller with the pointed portion inserted between a concrete panel (plate material) and a crosspiece (frame material). This is an oblique view showing the state in which the pointed part of the attachment is inserted between a concrete panel (plate material) and a crosspiece (frame material) and the part to be struck is struck with a hammer. This figure shows the state in which the pointed portion is inserted between the concrete panel (plate material) and the crosspiece (frame material) and then the slider is slid to separate the concrete panel and the crosspiece. FIG. 27B is a perspective view of the state shown in FIG. 27A as seen from a different angle. 27B is a view (side view) of the state shown in FIG. 27A viewed from yet another angle. This is a side view showing how the nail foot of a nail that is still stuck in a concrete panel is pushed down using a hook and a slider, thereby lifting the nail from the concrete panel. FIG. 28B is a diagram showing a vertical cross section of the rechargeable nail puller shown in FIG. 28A. This is a perspective view from a different angle showing how the nail foot, which is still stuck in a concrete panel (board material), is pushed down using a hook and slider, thereby lifting the nail out of the concrete panel. FIG. 28D is an enlarged view of the rechargeable nail puller shown in FIG. 28C. The figures show, in order from (a) to (d), the process of pushing down the nail foot of a nail stuck in a concrete panel using a hook and a slider, lifting the nail from the concrete panel, and then removing it. This is a perspective view showing how a frame material (batten) is clamped using the hook and slider of the rechargeable nail puller. This is a view from a different angle showing how the frame material (battens) is clamped using the hook and slider of the rechargeable nail puller. FIG. 10 is a perspective view showing, for reference, the relevant portion of a conventional battery-operated nail puller in which a hook is disposed at a position directly below a ball screw. FIG. 10 is a side view showing, for reference, a portion of a conventional battery-powered nail puller in which a hook is disposed directly below a ball screw. FIG. 2 is a block diagram showing an example of the configuration of a control device, an origin sensor, etc. FIG. 10 is a flowchart showing an operation flow of initial position detection (in the case of sensorless). FIG. 10 is a diagram illustrating an outline of an operation (pattern 1) of initial position detection (in the case of sensorless). FIG. 10 is a diagram illustrating an outline of an operation (pattern 2) of initial position detection (in the case of sensorless). FIG. 10 is a diagram illustrating an outline of an operation (pattern 3) of initial position detection (in the case of sensorless). FIG. 10 is a flowchart showing an operation flow of initial position detection (when a sensor is used). FIG. 10 is a diagram showing an outline of the operation (pattern 1) of initial position detection (when a sensor is present). FIG. 10 is a diagram showing an outline of the operation (pattern 2) of initial position detection (when a sensor is present). FIG. 10 is a diagram showing an outline of the operation (pattern 3) of initial position detection (when a sensor is present). FIG. 10 is a flowchart of a portion of the nail puller operation flow corresponding to a "nail puller mode." FIG. 10 is a flowchart of a portion of the nail pulling operation flow corresponding to a "nail pulling one cycle mode." FIG. 10 is a flowchart of the nail puller+clamp operation flow corresponding to the "nail puller mode." FIG. 10 is a flowchart of a portion of the nail puller+clamping operation flow corresponding to a "nail puller one cycle mode." FIG. 10 is a flowchart of the nail puller+clamp operation flow corresponding to the "clamp mode." 10 is a graph showing an example of a current waveform during reverse driving in a clamp mode. FIG. 10 is a flowchart of the portion of the operation flow of nail puller+initial position detection+clamp corresponding to the "nail puller mode." FIG. 10 is a flowchart of a portion of the operation flow of nail pulling + initial position detection + clamping that corresponds to the "nail pulling one cycle mode." FIG. 10 is a flowchart of the portion of the operation flow of nail removal + initial position detection + clamping corresponding to the "clamp mode."

Embodiments of the power tool according to the present invention will be described below with reference to the drawings.

[First embodiment]
As a first embodiment of the present invention, a power tool used as a rechargeable nail puller will be described (see FIG. 1 , etc.). The rechargeable nail puller 1 is a type of rechargeable power tool used for nail removal tasks such as removing a nail P that has penetrated a board or frame material such as a concrete panel Q or a batten R. The rechargeable nail puller 1 of this embodiment is a tool including a main body 10, a hook member 20, a slider 30, a cover 50, a motor 60, etc. (see FIGS. 1 to 19B , etc.). The hook member 20 fixed to the main body 10 is hooked onto a nail head Ph, and in this state, the slider 30 is extended from the main body 10 along the drive shaft DA, thereby performing a nail removal operation (see FIG. 19B , etc.). Below, the configuration of the rechargeable nail puller 1 will be described first, followed by a description of the operation of the rechargeable nail puller 1.

The main body 10 is the part that makes up the main body of the rechargeable nail puller 1, and in this specification refers to the part excluding the drive parts (slider 30, etc.). In this embodiment, the main body 10 mainly consists of a mechanism 11 that houses the motor 60, a grip 12 that is held by the user U (only the hand holding the rechargeable nail puller 1 is shown in Figures 7A and 8A) during use, and a battery housing 13 that houses the battery 66, etc. (See Figures 3 to 5, etc.).

The mechanical unit 11 houses the motor 60 as well as a drive mechanism 70 (e.g., a reducer 71, a screw shaft 72, etc., described below) for transmitting the driving force of the motor 60 to the slider 30 (see Figure 6B, etc.). This mechanical unit 11 is further provided with a main frame 14, a cover 50, a hook member 20, etc. (see Figure 6A, etc.).

The grip portion 12 is shaped to connect the relatively heavy and bulky battery storage portion 13 and the mechanical portion 11, excluding the area extending from the drive axis DA. The entire structure is designed to ensure good weight balance and ease of handling when a user grasps the grip portion 12 to lift and operate the cordless nail puller 1 (see Figures 4, 5, etc.). In this embodiment, the grip portion 12 is formed to extend perpendicular to the drive axis DA, but it may also be formed to extend slightly diagonally to facilitate nail pulling and other operations. A finger-operable trigger switch 122 is provided on the portion of the grip portion 12 closer to the mechanical portion 11 (see Figure 3, etc.). While not described in detail here, the grip portion 12 is shaped and sized to be easy to grip, and its surface is treated to be non-slip and easy to grip, such as by arranging a flexible material.

The battery housing 13 houses the rechargeable battery 66 and other components, and is the part of the main body 10 that tends to be heavy. In this embodiment, the battery housing 13 is configured as a roughly rectangular parallelepiped housing, with a shape and size that can easily accommodate a large battery 66 (see Figure 6A, etc.). The rechargeable nail puller 1 of this embodiment, which incorporates the rechargeable battery 66, can be used as a cordless hand tool to perform nail pulling operations without a cord. The surface of the battery housing 13 opposite the grip portion 12 is flat, and a rubber pad (not shown) or the like may be attached as needed. This surface serves as a resting surface 13S for when the tool is placed stably on the ground or floor when not in use (resting state) (see Figures 1, 3, etc.). The battery housing 13 of this embodiment is also provided with a strap 132 and a belt hook 134 (see Figure 2, etc.).

Here, we will discuss the relationship between the description in the drawings and the position of the rechargeable nail puller 1. The position (orientation of the rechargeable nail puller 1) of the rechargeable nail puller 1 of this embodiment when actually used for nail removal (in-use state) is not particularly limited. For example, to horizontally pull out a nail P that has penetrated a wall, the hook member 20 and slider 30 (described in detail later) can be used in a horizontal position, as in the placed state. To pull out a nail P that has penetrated a ceiling directly downward, the hook member 20 and slider 30 can be used in a position facing directly upward. However, in light of actual use situations, it is assumed that the action of pulling out a nail P directly upward from a board or frame material such as a concrete panel Q or batten R placed at the feet will be commonly performed. In this specification and drawings, assuming such a typical scenario, the state in which the hook member 20 and slider 30 are used in a downward-facing position will be referred to as the "in-use state" as a representative example of a typical use (see Figure 2, etc.). For convenience, the upper side in use (the direction upward along the drive axis DA) will be referred to as the "upper side," the lower side as the "lower side," the side where the mechanical unit 11 is located as seen from the user as the "front," and the side where the battery storage unit 13 is located as the "rear" (see Figure 7A, etc.).

The hook member 20 functions as a member that engages with part of the work object (in this embodiment, the head (nail head Ph) of the nail P to be pulled from a batten or the like), and has a hook (engagement portion) 22 formed at its tip. The shape of the hook 22 is not particularly limited as long as it can engage with the nail head Ph. In this embodiment, the hook 22 is formed by a pair of symmetrical claws that gradually narrow toward the front when viewed from below, like the tip of a typical nail puller (crowbar) (see Figure 5, etc.). Furthermore, if the hook 22 has a wedge shape that gradually narrows toward the front when viewed from the side (the left-right direction perpendicular to the front-to-back direction when in use), it will be easier to hook onto the nail head Ph (see Figure 6B, etc.). The hook member 20 with the hook 22 formed thereon is fixed to the main frame 14 of the mechanism unit 11 (see Figure 11, etc.). In this embodiment, the hook member 20 is formed in a cylindrical shape (see Figure 14A, etc.), and also functions as a guide member that guides the rod portion 32 of the slider 30 (described below) as it slides up and down (see Figure 13, etc.).

The main frame 14 is a frame formed in the mechanical unit 11 of the main body 10 so as to extend in the vertical direction (from top to bottom) along the drive axis DA (see Figure 12, etc.). In this embodiment, the main frame 14 is a pair of left and right plate-shaped members arranged symmetrically on either side of the drive axis DA (see Figures 9A and 9B, etc.). The upper end of the main frame 14 is attached and fixed to the frame base 15 (see Figure 13, etc.). A hook member 20 is fastened to the distal end (lower portion) of the main frame 14, for example, with fastening screws 24 on both sides (see Figure 14A, etc.). When fixed to the main frame 14, the hook member 20 does not change its relative position in the vertical direction (along the drive axis DA) within the mechanical unit 11. In addition to holding the hook member 20 thus fixed, the main frame 14 also serves as a guide member that guides the slider 30 as it slides in the vertical direction.

The slider (sliding member) 30 is a movable member that functions like a leg (pusher or push rod), sliding up and down to retract and retract relative to the main body 10, with a portion of it (tip 31) moving toward and away from the hook 22 of the hook member 20. By extending the slider 30 while the hook 22 of the hook member 20 is engaged with the nail head Ph, the hook 22 of the hook member 20, which is fixed to the main body 10, and the tip 31 of the slider 30 are moved away from each other, allowing the nail P to be pulled out (see Figures 7B, 8B, etc.). The slider 30 of the rechargeable nail puller 1 of this embodiment, configured in this manner, can be said to function like a tension rod when pushing the main body 10 together with the hook 22 against a nailed concrete panel Q, batten R, etc. (see Figure 16, etc.).

The specific configuration of the slider 30 is not particularly limited as long as it functions as described above, but in the present embodiment, which is a preferred example, the slider 30 is configured to have an integrated tip portion 31, rod portion 32, and side cover portion 33 that slide vertically along the main frame 14 provided on the main body portion 10 (see Figure 14B, etc.). The driving force of the motor 60 is transmitted to the slider 30 via a drive mechanism 70 including a screw shaft 72, and the slider 30 moves linearly along the drive axis DA.

The tip portion 31 is formed at the bottom of the slider 30 and consists of, for example, a substantially circular plate-like member. It acts as a tensioning part that abuts against a concrete panel Q, a crosspiece R, etc., and pushes up the main body portion 10 relative to the concrete panel Q or a crosspiece R (see Figures 7A, 8A, etc.).

The rod portion 32 is a rod-shaped member extending along the drive axis DA, and its lower tip is integrated with the tip portion 31 (see Figure 14B, etc.). The rod portion 32 is cylindrical, allowing the threaded shaft 72 to pass through its interior (see Figure 6A, etc.). A sleeve portion 32c with an internal thread 32b that threads onto the threaded shaft 72 is provided on the inner periphery of a portion of the rod portion 32, such as the upper flange portion 32a. As the threaded shaft 72 rotates, the rod portion 32, and thus the entire slider 30, moves linearly along the drive axis DA (see Figure 6B, etc.). The threaded shaft 72, the internal thread 32b, and the steel ball (not shown) interposed between the threaded shaft 72 and the internal thread 32b constitute a drive mechanism 70 for linearly moving the slider 30, such as a ball screw (indicated by the reference symbol 73 in Figure 9A, etc.) as in this embodiment. The rod portion 32 is formed so that its outer diameter is smaller than the inner diameter of the hook member 20, is positioned inside the hook member 20, and is guided by the inner surface of the hook member 20 as it slides (linearly moves) (see Figures 10B, 13, etc.). The rod portion 32 is fastened to the side cover portion 33 at its lower end with screws (such as flat head cap bolts) 39, forming an integrated unit (see Figures 10B, 11, etc.).

The side cover portion 33 is made of a member that forms the peripheral portion of the slider 30 (see Figure 14B, etc.). In this embodiment, the side cover portion 33 is provided to surround the main frame 14, and both sides of the side cover portion 33 are formed so that their cross-sectional shapes are channel-shaped, and the main frame 14 is sandwiched between the grooves (see Figures 9A, 9B, etc.). The side cover portion 33 formed in this manner slides (linearly moves) along the drive axis DA together with the tip portion 31 and rod portion 32, while being guided by the main frame 14 (see Figure 12, etc.). A cover 50 is provided around the side cover portion 33.

The cover 50 is a cylindrical member attached to the mechanism unit 11 so as to cover the periphery of the side cover unit 33 (see Figure 6A, etc.). In this embodiment, the cover 50 is arranged so as to hide the entire slider 30 except for the tip 31 when the slider 30 is in the retracted state (initial position) retracted into the main body unit 10 (see Figure 7B, etc.).

The motor 60 serves as a power source for driving (linearly moving) the slider 30, which is the movable part, via the drive mechanism 70. In this embodiment, the motor 60 is located in an upper position within the mechanism part 11 in the main body part 10 (see Figure 6A, etc.).

The drive mechanism 70 is configured to transmit the power of the motor 60 to drive (linearly move) the slider 30, which is the movable part. In this embodiment, the drive mechanism 70 includes a reducer 71 and a ball screw 73 (see Figure 6A, etc.). Although not shown in detail, the reducer 71 includes a gear train that appropriately reduces the rotation speed of the motor 60 and transmits it to the screw shaft 72 of the ball screw 73. The screw shaft 72 is arranged along the drive axis DA and rotates to drive (linearly move) the slider 30.

The control device (controller) 90 is built into the main body 10 and controls the motor 60. In this embodiment, the control device 90 is connected to the motor 60 for two-way communication, allowing it to send and receive control signals, and is also connected to the origin sensor 80, trigger switch 122, mode operation/display unit 92, and battery storage unit 13 (the battery 66 stored therein) (see Figure 31). The control device 90 also includes a communication circuit, converter circuit, inverter circuit, and an MPU for controlling the communication circuit for communicating with these components, although these are not specifically shown.

As described above, in this embodiment, the screw shaft 72 is provided along the drive axis DA, and the reducer 71 is provided above the screw shaft 72, on an extension of the drive axis DA. Furthermore, the motor 60 is provided above the reducer 71, on an extension of the drive axis DA (see Figure 6A, etc.). As a result, in the battery-powered nail puller 1 of this embodiment, the motor 60 and drive mechanism 70 (reduction gear 71, ball screw 73 and its screw shaft 72) are arranged in series and coaxially. This configuration, combined with the ability to reduce the overall height of the battery-powered nail puller 1, contributes to improved maneuverability and ease of aiming.

First, in a rechargeable nail puller 1 such as this embodiment, in which the hook member 20 is fixed rather than stroked as in conventional methods, and the hook member 20 is moved relatively by stroking the slider 30 instead, there is no need to provide space inside the main body 10 for stroking the hook member 20. With this configuration, the overall height (the length of the mechanism 11 along the drive axis DA) of the rechargeable nail puller 1 in the usage state (however, in the retracted state in which the slider 30 is retracted into the main body 10 and in its initial position) can be reduced by the length L1 (approximately equal to the stroke amount of the hook member 20) corresponding to the internal space required for the stroke of the hook member that would have been provided inside the main body 10 (see Figures 15 and 16, etc. In Figure 15(B), the reference numeral 1' indicates a conventional rechargeable nail puller for comparison). The height of the mechanism 11 in the initial position (retracted state) (the length from the tip 31 to the top of the mechanism 11 along the drive axis DA) is indicated by the symbol L2 (see Figure 16).

Second, the low overall height described above makes it easier to position the motor 60 on the drive axis DA (or an extension thereof). For example, while the motor 60 previously had to be offset within the handgrip 12 to avoid excessively high overall height, the present embodiment, which achieves a low overall height, allows it to be positioned on the drive axis DA (or an extension thereof). In this case, the handgrip 12 can be configured closer to the mechanism 11 and hook 22. Positioning the handgrip 12 closer to the mechanism 11 and hook 22 in this manner contributes to easier handling and aiming during actual nail removal operations, particularly the ability to hook the hook 22 onto the nail head Ph. Furthermore, because the force acting on the screw shaft 72 acts directly below (coaxially with) the screw shaft 72 regardless of the position or orientation of the nail P, there is no need to position the hook 22 directly below the drive axis DA, which also contributes to resolving the issue of "difficulty aiming at the nail."

In addition, arranging the motor 60, reducer 71, and screw shaft 72 in close proximity on a straight line means that the conventional power transmission mechanism (such as a bevel gear) that was previously arranged between them can be omitted, resulting in a simpler structure and contributing to smaller size and weight. Furthermore, this type of battery-powered nail puller 1 is conveniently easy to use in tight spaces.

Furthermore, when using a nail puller that strikes the nail foot Pt to remove the nail P, the force of the strike can cause the removed nail P to scatter. However, with the rechargeable nail puller 1 of this embodiment, as described above, it is possible to remove nails without scattering them.

Furthermore, when the main body 10 itself is structured to stroke and move in conjunction with the nail pulling operation (i.e., it moves together with the hook 22 to move away from the concrete panel Q, crosspiece R, etc.) as in the rechargeable nail puller 1 of this embodiment (see Figures 7A to 8B, etc.), there is also the advantage that it is easier for the user to experience the nail pulling operation. In other words, with a conventional structure in which the hook slides within the main body, a user working while holding the rechargeable nail puller in their hand can only confirm the nail pulling operation by seeing it with their eyes or hearing the sound of it operating, whereas with the rechargeable nail puller 1 of this embodiment, the user can directly feel the main body 10 itself stroke (rise) in conjunction with the nail pulling operation, making it easier for them to realize that the nail pulling operation has been completed.

Second Embodiment
As a second embodiment of the present invention, we will describe further features of the hook member 20 and the hook 22 of the live nail puller 1. Note that the description of other configurations of the live nail puller 1 that are common to those in the first embodiment will not be repeated.

<Structure that suppresses the effects of unbalanced load>
When configuring the above-described battery-powered nail puller 1, it is preferable to consider the problem of "unbalanced load" acting on the drive shaft. In the case of a conventional structure in which the nail P is pulled out by moving the hook 22', if the nail P penetrates straight into the concrete panel Q or the crosspiece R, the force acting on the drive shaft when the nail P is pulled out acts only in the axial direction, so no unbalanced load (unbalanced load) is applied (see FIGS. 17A and 17B). However, in reality, the nail P often penetrates at an angle (see FIG. 17C), and when the nail P is pulled out, the nail pull-out resistance occurs at a position offset from the drive shaft, which causes a lateral load to act on the drive shaft as an unbalanced load (see FIGS. 18A and 18B). In other words, resistance during nail removal occurs at the frictional resistance portion between the nail P and the concrete panel Q or batten R (the nail-driving member), more specifically, the portion of the nail P that penetrates the batten R (the portion marked with small dots in FIG. 18B ). Therefore, the reason why an unbalanced load acts on the nail P driven at an angle as described above can be explained by the fact that the portion that generates such resistance (the penetrating portion of the nail P) is misaligned (offset) with respect to the drive shaft. The unbalanced load causes the screw shaft 72' to tilt, and as the amount of nail P pulled increases, the tilt also increases. As a result, the load acting on the bearing portion of the screw shaft 72' can cause uneven wear and reduce durability. Since an unbalanced load occurs due to misalignment between the drive shaft and the nail, this can be even more likely if the hook 22 is positioned offset from the drive shaft DA, as in this embodiment.
In order to address this issue of uneven load and minimize its effects, one possible configuration is to position the hook that catches the nail head on the drive shaft in a conventional mechanism to prevent uneven load from occurring. However, while this type of positioning is effective in improving durability, it has the disadvantage of making it difficult to see (aim) the tip of the nail. Furthermore, it cannot avoid the uneven load that occurs when extracting a nail that has penetrated at an angle.
In this regard, the present embodiment, which comprehensively takes into consideration various issues, employs a rigid structure that makes it easy to see (aim) the tip of the nail and is less susceptible to the effects of uneven loads.
That is, the hook, which is subjected to an unbalanced load in the diagonal or lateral direction, is supported not by a screw shaft for generating a driving force but by the highly rigid main frame 14. Also, a guide member is provided to guide the sliding of the slider 30, which is the movable part, to prevent unbalanced loads from acting on the female thread 32b.
This eliminates the need to provide the hook 22 directly below (on an extension of) the drive shaft DA, which allows the hook 22 to be offset, thereby solving the problem of "it being difficult to aim the nail."

<Offset hook placement>
The hook 22 of the hook member 20 is positioned offset from the drive axis DA (see FIG. 10A, etc.). In this embodiment, the hook 22 of the hook member 20 is formed to protrude perpendicular to the drive axis DA and faces horizontally when in use (see FIG. 6A, etc.). Furthermore, at least a portion of the hook 22 is located outside the cover 50 so that it can be seen (see FIG. 5, etc.). The advantages of the above configuration are as follows. Some conventional battery-operated nail pullers have the hook 22' positioned directly below the screw shaft 72' of a ball screw or the like (in other words, on an extension of the drive axis DA) (see FIGS. 30A and 30B). However, this makes it difficult to see the hook 22' and determine its position, which can make it difficult to engage the hook 22' on the nail head Ph. In this regard, in the case of the rechargeable nail puller 1 in which the hook 22 is offset as in the present embodiment, the hook 22 is easier for the user to see because it is offset from the drive axis DA, making it easier for the user to hook the hook 22 onto the nail head Ph (see Figures 7A, 7B, etc.).

<Protruding leg at the tip of the slider>
In this embodiment, since the hook 22 is disposed in an offset position as described above, the slider 30, particularly the tip portion 31 thereof, has a structure suitable for the offset positioning of the hook 22. That is,
(1) The tip 31 of the slider 30 is provided with protruding legs 35 that protrude in a direction perpendicular to the drive axis DA (see FIG. 10A, etc.). The protruding legs 35 are formed with a size and shape sufficient to eliminate the effects of external forces (moments) that may act when the offset hook 22 pulls out the nail P. As a preferred example, in this embodiment, a pair of protruding legs 35 that are sufficiently large compared to the hook 22 (see FIG. 19A, etc.) and symmetrically arranged on the left and right are provided on the tip 31 (see FIG. 5, etc.). The length from the drive axis DA to the tip of the hook 22 is L4, and the protruding legs 35 are further forward by a length L5 (see FIG. 19B). The pair of protruding legs 35 are spaced apart at a greater distance than the hook 22 of the hook member 20 so that the hook 22 can be positioned between them (see FIG. 7B, etc.).
(2) The tip 31 of the slider 30 is formed with a flat surface 31f that contacts the concrete panel Q, the crosspiece R, or the like (see FIG. 19A, etc.). This flat surface 31f is sized or shaped to at least eliminate the effects of external forces (moments) that may act when the offset hook 22 pulls out the nail P. In this embodiment, the flat surface 31f extends forward beyond the offset amount L of the hook 22 (which in this specification refers to the distance between the imaginary center axis Pc and the drive axis DA when the nail P hooked on the hook 22 is assumed to be straight). In other words, the length L3 from the drive axis DA to the front end of the flat surface 31f is sufficiently longer than the offset amount L), thereby widening the contact area (ground contact area) with the concrete panel Q, the crosspiece R, or the like (see FIG. 19B, etc.). Needless to say, the lower surface of the protruding leg 35 described above may be entirely or mostly flat.

<Rotating structure of hooks, etc.>
When the hook 22 is offset and protrudes perpendicular to the drive axis DA as described above, it is preferable to make the hook 22 rotatable (pivotable) about the drive axis DA. This reduces operational constraints that would otherwise be imposed on the user of the cordless nail puller 1, such as the need to always use the cordless nail puller in a fixed orientation, and further improves ease of use (see FIGS. 20A, 20B, etc.). In this embodiment, a rotatable portion 21 and an O-ring 26 are provided at the lower tip of the hook member 20, allowing the orientation of the hook 22 formed on the rotatable portion 21 to be changed (see FIGS. 21A, 21B, 22A, etc.). The specific configuration of the rotatable portion 21 is not particularly limited. As an example, in this embodiment, a ring-shaped rotatable portion 21 having a larger diameter than the cylindrical portion 23 is provided at the lower tip portion of the cylindrical portion (indicated by the symbol 23) of the hook member 20, and the orientation of the hook 22 can be changed by manually rotating this rotatable portion 21 around the drive axis DA (see Figures 22A, 23B, etc.).

The O-ring 26 is an annular member made of, for example, rubber, that is provided between the rotatable portion 21 and the cylindrical portion 23 (see Figure 23B, etc.). This O-ring 26 functions as a resistor that applies a predetermined resistance to the rotation of the rotatable portion 21 around the drive axis DA, allowing relative rotation of the rotatable portion 21 while preventing the rotatable portion 21 from accidentally rotating after the orientation of the hook 22 is changed.

In the cordless nail puller 1 of this embodiment, the orientation of not only the hook 22 but also the protruding leg 35 of the slider 30 can be changed. For example, in this embodiment, the rod portion 32 and tip portion 31 of the slider 30 are separated, and a rotatable portion 34 and an O-ring 38 are provided between them to allow relative rotation, allowing the tip portion 31, side cover portion 33, and protruding leg 35 to rotate (pivot) together relative to the rod portion 32 (see Figure 24B, etc.). The rotatable portion 34 can be configured, for example, by a screw that rotatably attaches the tip portion 31 to the lower end of the rod portion 32 (see Figure 24B, etc.).

The O-ring 38 is an annular member made of, for example, rubber, that is provided between the rod portion 32 and the tip portion 31 (see Figure 24B, etc.). This O-ring 38 functions as a resistor that applies a predetermined resistance to the rotation of the tip portion 31 and other components around the drive axis DA, allowing relative rotation of the tip portion 31 and other components while preventing the protruding leg portion 35 and tip portion 31 from accidentally rotating after the orientation of the protruding leg portion 35 is changed.

In addition, in this embodiment, the protruding leg 35 and the hook 22 are configured so that, when the slider 30 is in its initial position retracted into the main body 10, the protruding leg 35 and the hook 22 at least partially overlap with each other in the axial direction of the drive shaft DA (see Figure 23B, etc.). In other words, if the protruding leg 35 is rotated in the retracted state (initial position), it will interfere with the hook 22 during rotation. Therefore, in the cordless nail puller 1 of this embodiment, rotating the protruding leg 35 in the retracted state (initial position) will also rotate the hook 22 by the same amount. For example, if the orientation of the hook 22 needs to be changed depending on the position or shape of the nail P, simply rotating the outer protruding leg 35 will change the orientation of the hook 22 simultaneously, which is convenient (see Figures 22A, 22B, etc.). Furthermore, the fact that the protruding leg 35 and the hook 22 always face in the same direction means that the protruding leg 35 is always located directly below the hook 22 when the nail P is being pulled out (see Figures 24A, 24B, etc.). Therefore, regardless of the direction in which the hook 22 is oriented, the external force (moment) that may act when the offset-positioned hook 22 pulls out the nail P is received by the protruding leg 35 directly below, eliminating its effects.

<Structure that returns the orientation of the hook and protruding leg>
Furthermore, in this embodiment, even if the orientation of the hook 22 and the protruding leg 35 is changed to perform a nail removal operation, a mechanism is in place to return the orientation of the hook 22 and the protruding leg 35 to their original orientation (facing forward in this embodiment) after the operation (see FIGS. 22A, 23A, etc.). Such a mechanism can be configured, for example, as a device including a guide member that guides the slider 30 and the rotatable portion 21 of the hook member 20 and rotates them a predetermined amount so that the hook 22 and the protruding leg 35 face forward during the period from a state in which the slider 30 protrudes most from the main body 10 and has removed the nail P (protruding state) (see FIGS. 24B, 24C, etc.) to a state in which the slider 30 returns to the initial position in which the slider 30 is retracted (see FIG. 23B, etc.) (for example, a device including a combination of a spiral guide and a protrusion guided along the guide, which defines the circumferential position of the protruding leg 35 of the slider 30 and the rotatable portion 21 of the hook member 20 as the slider 30 slides up and returns to the initial position).

<Structure for clamping components>
The main purpose of the cordless nail puller 1 equipped with the hook 22 and protruding leg 35 described above is, of course, to pull nails, but it can also be used as a clamping device for clamping members arranged perpendicular to the drive shaft DA. For example, when clamping the battens of two concrete panels Q together to bring the panels Q into contact with each other without any gaps, the battens R can be sandwiched between the underside of the hook 22 and the upper surface of the protruding leg 35 (see Figures 29A and 29B). When used for such purposes, the hook 22 and the protruding leg 35 can be said to function as a holding part that sandwiches the member to be clamped and holds it in place.

The rechargeable nail puller 1 of this embodiment is a single power tool that can be used for practical purposes other than nail pulling. This also makes it possible to meet the latent demands of on-site workers, who often consider it costly and cumbersome to have different tools for each task.

[Third embodiment]
As a third embodiment of the present invention, a description will be given of a rechargeable nail puller 1 that further improves convenience by enabling it to be used for demolition work of concrete panels Q, battens R, etc. In this rechargeable nail puller 1, a tapered pointed portion is formed on a part of the slider 30, and by striking the slider 30 with a hammer or the like to drive the pointed portion, work such as separating plate materials or frame materials such as concrete panels Q and battens R can be easily performed (see FIG. 25A, etc.).

<Structure suitable for demolition work of boards, etc.>
In this embodiment, a tapered portion 36 is formed on a portion of the protruding leg 35 of the slider 30 (see FIG. 25A, etc.). The tapered portion 36 is a wedge-shaped tapered portion facing away from the drive shaft DA. For example, in this embodiment, the tapered portion 36 is formed on a portion of the cordless nail puller 1 that faces forward in the initial retracted position, facing perpendicular to the drive shaft DA (see FIG. 25A, etc.). The shape of the tapered portion 36 is not particularly limited as long as it is tapered. As in this embodiment, both the upper surface 36t and the lower surface 36b may be inclined (see FIG. 25C, etc.), or only one of the upper and lower surfaces may be inclined and the other surface may be horizontal in use. Furthermore, the upper surface 36t and the lower surface 36b may be flat or gently curved. In short, it is sufficient that the slider 30 has a wedge shape that exerts a force to separate plate materials or frame materials such as concrete panels Q and crosspieces R when the slider 30 is struck to drive the tapered portion 36 into the tapered portion 36.

In this embodiment, the tapered portions 36 are provided at the front ends of the pair of left and right protruding leg portions 35, and are formed symmetrically about an imaginary plane (indicated by symbol VP in Figure 4) including the drive shaft DA.
Furthermore, the left and right tapered portions 36 are spaced apart so that the hook of the hook member 20 fits between them (see FIG. 7B, etc.).

A struck portion 37 is formed on the slider 30 on the side opposite the tapered portion 36 when the drive axis DA is used as the reference (the rear side when in use) (see Figure 25B, etc.). In this embodiment, the struck portion 37 is shaped to protrude toward the side opposite the tapered portion 36 when the drive axis DA is used as the reference, thereby clearly indicating to the user the location to be struck with the hammer 300 and preventing the hammer 300 from striking the cover 50 of the cordless nail puller 1 when striking (see Figure 26, etc.). Taking the latter point into consideration in particular, the slider 30 may be formed so that the struck portion 37 protrudes sufficiently beyond the surface of the cover 50 (see Figure 25C, etc.).

At least the portion of the slider 30 used for the impact operation (including the tapered portion 36 and the impacted portion 37) is made of a material with sufficient rigidity to withstand impacts. This portion may be made of metal, such as a cast iron. Alternatively, this portion may be made of a detachable attachment (indicated by the reference symbol 40 in Figure 25B). If a detachable attachment 40 including the tapered portion 36 and the impacted portion 37 is used, the tapered portion 36 or the impacted portion 37 can be easily replaced even if they are damaged. The entire attachment 40 may be made of metal, such as a cast iron. The attachment 40 may be rotatable around the drive axis DA relative to the rod portion 32 of the slider 30, etc.

In addition, in this embodiment, the tapered portion 36 formed on the slider 30 as described above is sized so that its tip 36a is positioned outside the hook 22 of the hook member 20 (in other words, farther from the drive axis DA), and the outline of the tapered portion 36 is laid out outside the outline of the hook 22 (in other words, the hook 22 is hidden within the projection of the protruding leg 35 or its tapered portion 36 when viewed from the side) (see Figure 25C, etc.). By forming the tapered portion 36 larger than the hook 22 and positioning it further forward in this way, it is possible to avoid the hook 22 acting as a resistance when inserting the tapered portion 36 into the gap between the concrete panel Q and the crosspiece R, for example.

With the rechargeable nail puller 1 described above, the tapered portion 36 can be inserted into the gap between, for example, a concrete panel Q and a batten R, and the striking portion 37 can be struck with the hammer 300 to widen the gap between the concrete panel Q and the batten R using striking force, just like using a crowbar (see Figure 26, etc.). By sliding the slider 30 with the hook 22 and protruding leg 35 deeply inserted in this way, the gap between the concrete panel Q and the batten R can be further widened, making them easier to separate (see Figures 27A, 27B, 27C, etc.). Furthermore, if the nail head Ph is slightly raised from the concrete panel Q or the batten R but firmly penetrates it, making it difficult to hook the hook 22 onto the nail head Ph, the striking portion 37 can be struck with the hammer 300 to gradually push the hook member 20 forward, until the hook 22 is fully engaged with the nail head Ph.

<How to use it to lift nails from boards, etc.>
The rechargeable nail puller 1 configured as described above can also be used to lift nails P that have been stuck into boards or frame materials such as concrete panels Q and crosspieces R (see Figure 28A, etc.).

Nails P driven into formwork panels are often driven with the nail heads Ph raised, considering the dismantling that will be performed after the concrete has hardened. However, there may be cases where the raised width is insufficient and it is difficult to hook the hooks 22. Therefore, it is convenient to raise the nail P even further. In such cases, the rechargeable nail puller 1 can be used to raise the nail P even further. Specifically, for example, if a nail P remains embedded in a concrete panel Q that has been separated from its battens (see Figure 28E(a)), first, a push-down tool 400 is installed between the pair of left and right hooks 22. With the slider 30 slid outward, the protruding leg 35 is placed against the surface of the concrete panel Q (the surface with the nail heads Ph), and the push-down tool 400 is used to press down the nail foot Pt (see Figures 28A, 28B, 28C, 28D, and 28E(b)). When the nail head Ph has lifted off the surface of the concrete panel Q (see Figure 28E(c)), the nail P can be extracted with the rechargeable nail puller 1 (see Figure 28E(d)), which may enable smooth and efficient work. The push-down tool 400 can be anything that can push down the tip of the nail foot Pt, and can be a jig that can be attached and detached to the hook 22, for example.

The cordless nail puller 1 of this embodiment is a single power tool that can be used for practical purposes other than nail pulling. This also makes it possible to meet the potential needs of workers in the field, where having different tools for each task is often considered costly and cumbersome.

[Fourth embodiment]
As a fourth embodiment of the present invention, various operations of the battery-powered nail puller 1 and their control will be described (see Figs. 31, 32A, etc.).

<Control device>
The control device 90 causes the motor (drive source) 60 to cause the slider (sliding member) 30 to perform a predetermined operation in response to a trigger signal input from the outside.

<Origin sensor>
The origin sensor 80 is provided as a means for detecting that the slider 30 is at its initial position. The origin sensor 80 may be an optical sensor that detects the position of the slider 30 on the drive axis DA. Alternatively, the origin sensor 80 may be a sensor that determines the position or amount of movement of the slider 30 based on the amount of rotation of the motor 60. Alternatively, the origin sensor 80 may be a switch that is arranged to detect that the slider 30 is at a predetermined position when it comes into contact with the slider 30.

<Operation mode>
The rechargeable nail puller 1 of this embodiment has a plurality of selectable operating modes for operating the slider 30 depending on the type of work to be performed on the work object. The operating modes are various operating methods that are set so that the user can select one depending on how the rechargeable nail puller 1 moves when pulling out nails, or on the manner or desired operation when used for purposes other than nail pulling. The rechargeable nail puller 1 of this embodiment has a "nail pull mode," a "nail pull one-cycle mode," and a "clamp mode" that the user can select by operating a mode operation/display unit (indicated by reference numeral 92 in FIG. 31 ) for operating the modes.

<Nail removal operation flow>
An example of an operation flow when controlling the nail pulling operation in the rechargeable nail puller 1 will be described (see FIGS. 34 and 35).

After the main power is turned on (step SP301), an operation mode is selected (step SP303). For nail pulling applications, the operation mode is set to "nail pull mode" or "nail pull one-cycle mode," which can be selected by the user by operating a mode selection switch (not shown), so that the user can select how the rechargeable nail puller 1 operates during nail pulling depending on the type of nail pulling to be performed and the desired operation.

<Nail puller operation flow (nail puller mode)>
If the "nail pull mode" is selected in step SP303, the initial position drive operation is first performed (step SP311). As described above, this is a series of automatic operations for detecting the position of the drive unit of the slider 30 and moving the slider 30 to a predetermined initial position. If a mode change is instructed, the slider 30 moves to an initial position that differs for each mode, but if there is no mode change, this step may be skipped.

After the initial position drive operation (step SP311), the movement amount setting is reflected (step SP312). This step is for appropriately setting the movement amount (sliding length) of the slider 30 during the upcoming nail removal operation, and may be configured so that it can be switched by operating a switch (not shown) that can be operated or input by the user. If a switch is used, the switch may be any type, such as a tactile switch or dial switch. Although a detailed explanation will be omitted, options such as "auto," which automatically sets the movement amount, or "standard," which sets a standard movement amount, may be selectable. The movement amount (sliding length) of the slider 30 may be controlled based on the rotation amount of the motor (e.g., stepping motor) 60. In this case, the rotation amount of the motor 60 may be set in advance in the control device.

While the trigger OFF signal is being input, SP303, SP311, SP312, and SP313 are continuously executed, and when the trigger is turned ON, the nail removal operation begins (step SP314).

In the nail removal operation step, the motor 60 is driven in the forward direction to move the slider 30 in the direction protruding from the main body 10 (i.e., the nail removal operation direction described above) (step SP314). When the amount of movement of the slider 30 reaches the preset amount of movement (step SP312) (step SP315), the motor 60 is stopped to stop the drive of the slider 30 (step SP316). After the drive of the slider 30 is stopped, the system waits until the trigger is turned off (step SP317). That is, the system waits until the trigger switch 122 is released from the state in which the user's finger is still pulling the trigger switch 122 (trigger ON state) (or the force pulling the switch is released) and the trigger switch 122 returns to its original state (trigger OFF state). When the trigger signal is turned off (i.e., the trigger is turned off), the motor 60 is rotated in the reverse direction to move the slider 30 back to its initial position (retracted into the main body 10) (step SP318). When the slider 30 returns and reaches its initial position (step SP319), the motor 60 and slider 30 are stopped (step SP320), and the series of operations (nail pull mode) is completed. After the series of operations is completed, the process returns to step SP303 to prepare for the next nail pull operation and performs the same operations as above in response to inputs (see Figure 34). As described above, in the nail pull mode, the slider 30 is caused to perform a predetermined operation in response to an externally input trigger signal, such as sliding the slider 30 a predetermined length when the trigger signal is turned on.

<Nail puller operation flow (nail puller 1 cycle mode)>
The operation flow when the "nail pull one-cycle mode" is selected in step SP303 will be described (see FIG. 35, etc.). In the "nail pull one-cycle mode," the initial position drive operation is performed (step SP321), and then the following operations are performed in sequence (see FIG. 35): setting the movement amount (step SP322), waiting for the trigger to turn ON (step SP323), performing the nail pull operation (step SP324), reaching the set movement amount (step SP325), and stopping the drive (step SP326). The operations up to this point are the same as those in steps SP311 to SP316 in the "nail pull mode" described above (see FIGS. 34 and 35).

After this, in the nail pull one-cycle mode, regardless of the state of the trigger switch 122 (trigger ON or trigger OFF), the motor 60 is rotated in the reverse direction to move the slider 30 back to its initial position (step SP327), and it is not maintained in an extended state. When the slider 30 returns and reaches its initial position (step SP328), the drive of the motor 60 and slider 30 is stopped (step SP329). After the drive is stopped, the system waits until the trigger is turned OFF (step SP330). When the trigger switch 122 returns from the state in which it is being pulled by the user's finger (trigger ON state) to its original state (trigger OFF state), the system returns to step SP303 and prepares for the next nail pull operation (see Figures 34 and 35). As described above, in the nail pull one-cycle mode, when the trigger signal is turned ON, the slider 30 is slid a predetermined distance and then returned to its initial position.

<Nail puller + clamp operation flow>
The rechargeable nail puller 1 may be configured to perform clamping operations in addition to nail pulling operations. An example of an operation flow in this case where both the nail pulling operations and clamping operations can be performed will be described (see FIGS. 36A to 36C).

After the main power is turned on (step SP501), one of the following operating modes is selected (step SP503): "nail pull mode," "nail pull one-cycle mode," or "clamp mode." The operational flow when "nail pull mode" is selected (steps SP511 to SP520, see Figure 36A) is the same as that for the "nail pull mode" (see Figure 34) described above. The operational flow when "nail pull one-cycle mode" is selected (steps SP521 to SP530, see Figure 36B) is the same as that for the "nail pull one-cycle mode" (see Figure 35) described above, so they will not be described here. An example of the operational flow when "clamp mode" is selected is described below (see Figure 36C).

<Clamp operation flow (clamp mode)>
If the "clamp mode" is selected in step SP503, the motor 60 is driven in the forward direction to drive the slider 30 to the position where it is most protruded from the main body 10 (hereinafter also referred to as the "maximum extension position") (step SP531), and the system waits until the trigger switch 122 is pulled and a "trigger ON" signal is transmitted (step SP532). When the trigger is ON, the motor 60 is rotated in the reverse direction to initiate a clamping operation (an operation in which a workpiece, such as a pair of battens of a concrete panel Q, is sandwiched between the hook 22 and the protruding leg 35) (step SP533). If a predetermined load (clamp load) is generated before the slider 30 reaches the initial position after the clamping operation has started (NO in step SP534, YES in step SP535), the system stops driving the motor 60 and slider 30 at that point (step SP536), and the system waits until the trigger is OFF while maintaining the workpiece clamped (step SP537). That is, the system waits until the trigger switch 122 is released from the state where the user's finger is still pulling the trigger switch 122 (trigger ON state) (or the force pulling the switch is released) and the trigger switch 122 returns to its original state (trigger OFF state). Once the trigger switch 122 is in the trigger OFF state, the system waits until the trigger switch 122 is pulled and returns to the trigger ON state (step SP538). Once the trigger switch 122 is in the trigger ON state, the motor 60 is rotated forward again to drive the slider 30 back to the maximum extension position (step SP540). Once the slider 30 reaches the maximum extension position (step SP541), the drive of the motor 60 and the slider 30 is stopped (step SP542). The system then waits until the trigger switch 122 is in the trigger OFF state (step SP543). Once the trigger switch 122 is in the trigger OFF state, the system returns to the step of selecting the operation mode (step SP503).

Also, if the slider 30 reaches the initial position in step SP534 (YES in step SP534), it is determined that the work object or the like was not clamped while the slider 30 moved from the maximum extension position to the initial position, and the process transitions to step SP539, where the drive is stopped (see Figure 36C).

The load acting on the slider 30 and motor 60 during operation of the slider 30 can be detected based on the current value of the motor 60. For reference, an example of the current waveform of the motor 60 when the motor 60 is driven in reverse in clamp mode is shown here (see FIG. 37). The current value when the work object is clamped is greater than the current value when the motor 60 is driven in reverse in nail pull mode (specifically, when the slider 30 is returned to its initial position (step SP518) after the nail pull operation (see FIG. 36A)). Therefore, if a threshold current C1 during reverse drive in nail pull mode is set, by setting a value C2 greater than the current C1 as the threshold current during reverse drive in clamp mode, it is possible to detect the completion of the clamp operation based on the threshold current C2 (see FIG. 37).

<Operation flow for initial position detection (sensorless)>
Next, we will explain the operational flow for positioning the slider 30 and other components to their initial positions in response to a trigger signal from the rechargeable nail puller 1. Here, we will explain three patterns for a sensorless rechargeable nail puller 1, i.e., one that does not have a sensor to detect the position of the slider 30: Pattern 1, in which there is no room for pinching; Pattern 2, in which there is room for pinching and the operation ends normally; and Pattern 3, in which pinching occurs and the operation ends abnormally (see FIGS. 32A to 32D ). The flow diagram for each of the three patterns 1 to 3 is shown in FIG. 32A . In addition, in FIGS. 32B to 32D , a location on the slider 30 is designated as the "operating portion," and the corresponding portion is indicated by a hollow triangle to show the movement and amount of the slider 30. Note that the sliding movement of the slider 30 (toward the bottom of the rechargeable nail puller 1) relative to the main body 10 of the rechargeable nail puller 1 (see FIG. 7B , etc.) is represented in FIGS. 32B to 32D as a movement to the right (the direction of the nail pulling operation) as viewed in the figure. Furthermore, parts that are related between the operations in the flow (see FIG. 32A) and the operations in each pattern (see FIGS. 32B to 32D) are marked with the same numbers in parentheses.

<Operation flow for initial position detection (sensorless) (Pattern 1)>
In the rechargeable nail puller 1, when the main power is turned on (step SP101), this serves as an initial trigger to start the operation flow for detecting the initial position of the slider 30 (see FIGS. 32A and 32B). When the trigger signal is turned on and the flow starts, the motor 60 is first driven in the reverse direction (step SP110), and it is determined whether a high load (a load exceeding a predetermined value) is detected when the slider 30 hits a position where it cannot slide any further (hereinafter referred to as the "reverse limit position") (step SP111). If a high load is detected (YES in step SP111), the motor 60 is driven in the forward direction (step SP141), and it is determined whether the slider 30 has moved a predetermined amount equivalent to the specified amount _X0 for initial positioning (step SP142).

Here, the "specified initial position setting amount _X0 " refers to an amount equivalent to the difference between the "target initial position _W0 " where the slider 30 should be positioned at the beginning of the operation and the above-mentioned "reverse rotation limit position _W1 " (see FIG. 32B). In this embodiment, the slider 30 is first pulled back to the reverse rotation limit position _W1 , and then slid a predetermined length equivalent to the specified initial position setting amount X0 _to position the slider 30 at the target initial position _W0 (to position the slider 30). Specifically, when it is detected that the slider 30 has moved the "specified initial position setting amount _X0 " from the "reverse rotation limit position _W1 " (YES in step SP142), it is determined that the slider 30 has reached the "target initial position _W0 ," and the motor 60 is stopped (step SP143). This completes the series of initial position detection operations (step SP144), and the process transitions to normal control (control associated with operations such as nail pulling) (step SP150).

<Operation flow of initial position detection (sensorless) (pattern 2)>
In the following Pattern 2, an operation flow will be described in which there is a possibility that some member may be caught during the movement of the slider 30 associated with initial position detection (see FIGS. 32A, 32C, etc.).

The process from step SP101 to step SP111 is the same as that of pattern 1 (see FIG. 32A). In step SP111, if "a high load is not detected when the slider 30 hits the reverse rotation limit position _W1" (NO in step SP111), it is determined whether the movable unit has moved a specified amount _X1 (whether it has entered the main body unit 10) (step SP121). The specified amount _X1 here is different from the specified amount _X0 for initial positioning described above. The flow of returning to step SP111 is repeated until the amount of movement of the movable unit reaches this specified amount _X1 (NO in step SP121). When the amount of movement of the movable unit reaches the specified amount _X1 (YES in step SP121), the motor 60 is rotated forward (step SP122), and the slider 30 is moved in the direction protruding from the main body unit 10, and it is determined whether a high load is detected at the forward rotation limit position _W2 (step SP123). The forward rotation limit position _W2 here is a position where the slider 30 cannot slide any further in the protruding direction (see FIG. 32C), and is the end of the possible stroke width of the slider 30. Here, the process waits until a high load exceeding a predetermined value is detected, and if detected, it is determined that the slider 30 has reached the forward rotation limit position _W2 , and the process proceeds to step SP124 (see FIG. 32A).

In step SP124, the motor 60 is rotated in the reverse direction, moving the slider 30 in the direction of being pulled into the main body 10. Thereafter, it is determined whether a high load is detected at the reverse limit position _W1 (step SP125). Here, it waits until a high load exceeding a predetermined value is detected, and if detected, it is determined that the slider 30 has reached the reverse limit position _W1 .

Next, it is determined whether the slider 30 has moved by the abnormality prevention specified amount _Xap or more (step SP126). The abnormality prevention specified amount _Xap is an amount set as an index for determining whether an abnormality such as the slider 30 getting caught on something or a foreign object getting caught during its movement (in this embodiment, from the forward rotation limit position _W2 to the reverse rotation limit position _W1 ) has occurred. For example, the abnormality prevention specified amount Xap is set as an amount that occupies a predetermined percentage of the possible stroke width of the slider 30 (see FIG. 32C). If the slider 30 has moved by the abnormality prevention specified amount Xap _or more in step SP126, it is determined that no abnormality has been found in the series of operations up to this point, and the process proceeds to the above-mentioned step SP141. From step SP141 onwards, the same operations as those in the above-mentioned pattern 1 are performed (steps SP141 to SP144, step SP150). On the other hand, if the slider 30 has not moved by the abnormality prevention specified amount Xap _or more in step SP126, the process proceeds to step SP131 (see FIG. 32A). Step SP131 will be described in the following pattern 3.

<Operation flow for initial position detection (sensorless) (pattern 3)>
In the following Pattern 3, we will mainly explain the flow when the slider 30 does not move by the abnormality prevention specified amount Xap _or more in step SP126 (see Figures 32A, 32D, etc.). If the slider 30 does not move by the abnormality prevention specified amount Xap _or more in step SP126, it is determined that an abnormal lock has occurred due to an event such as the slider 30 getting caught on something or a foreign object getting caught while moving from the forward rotation limit position _W2 to the reverse rotation limit position _W1 (step SP131). In this case, the initial position detection operation flow is terminated. The user may also be notified of the occurrence of the abnormal lock by turning on a lamp or sounding a buzzer provided on the main body 10 of the cordless nail puller 1.

<Operation flow for initial position detection (with sensor)>
Next, another embodiment of the operational flow for positioning the slider 30 and other components at their initial positions in response to a trigger signal in the rechargeable nail puller 1 will be described. Three patterns will be described below for the rechargeable nail puller 1 equipped with a position detection sensor: Pattern 1, in which detection starts when "operating unit position < origin position W _{op ,} " Pattern 2, in which detection starts when "origin position W _op < operating unit position," and Pattern 3, in which detection starts when "operating unit position = origin position W op " (see FIGS. 33A to 33D ). The flow chart representing the operations of each of the three patterns 1 to 3 is shown in FIG. 33A . The "operating unit" is as described in the above embodiment. The "origin position" here refers to the position or range where the "operating unit" should be when the slider 30 is in its initial position. In this embodiment, the position is detected using a sensor (for example, an origin sensor indicated by reference numeral 80 in FIG. 31 ) that detects whether the operating unit is at the origin position W _op . There are no particular limitations on the specific examples that can be used as the detection sensor, but one example is a non-contact Hall IC that detects a magnet attached to the slider 30.

When the main power supply of the rechargeable nail puller 1 is turned on (step SP201), this serves as the initial trigger, starting the operational flow for detecting the initial position of the slider 30 (see Figures 33A and 33B). Once the trigger signal is turned on and the flow starts, the state of the origin sensor is checked to determine whether the origin sensor has detected the moving part of the slider 30 or is not detecting it (step SP203). If the origin sensor is not detecting it, the operational flow first proceeds according to pattern 1 (see Figure 33A).

<Operation flow for initial position detection (with sensor) (Pattern 1)>
In pattern 1, first, the motor 60 is driven in the forward direction (step SP211), and the slider 30 is moved in the direction in which it protrudes from the main body 10 (the direction of the nail-pulling operation) (see FIG. 33A). Then, the process waits to see if the origin sensor detects the operating part (step SP212). If it does, the process proceeds to step SP213. On the other hand, if the operating part of the slider 30 has moved a specified amount without detection, the process proceeds according to the operation flow of pattern 2, which will be described later.

When the origin sensor detects the moving part (step SP212), the system waits until the origin sensor no longer detects the moving part (step SP213). When the slider 30 is moved and no longer detects the moving part, it is determined that the moving part has passed the origin position _W (see FIG. 33B). At this point, the motor 60 is rotated in the reverse direction (step SP214) to move the slider 30 back. When the origin sensor subsequently detects the moving part (step SP215), it is determined that the moving part has passed the origin position _W and returned to the origin position _W. In this embodiment, the motor 60 is stopped (step SP241), and the initial position detection sequence is completed (step SP242), after which the system transitions to normal control (control associated with operations such as nail removal) (step SP250).

<Operation flow for initial position detection (with sensor) (Pattern 2)>
The above-mentioned pattern 1 corresponds to the case where, when the main power is turned on (initial trigger), "operating part position < origin position W _op " (the origin position W _op is located in the direction of the nail pulling out operation more than the operating part)." However, if, during the operation flow, it is discovered that, at the time of the initial trigger, the opposite is actually true, "origin position W _op < operating part position" (the operating part is located in the direction of the nail pulling out operation more than the origin position W _op ), then the operation flow of pattern 2 described below will proceed (see Figures 33A and 33C).

That is, after driving the motor forward (step SP211), in step SP212, which waits to see if the origin sensor detects the operating part, if the operating part of the slider 30 moves a specified amount _X2 without detection (see FIG. 33C), the motor 60 is rotated in the reverse direction (step SP222) to move the slider 30 back. After that, if the origin sensor detects the operating part (step SP223), it is determined that the operating part, which was originally "origin position W _op < operating part position," is now at origin position W _op , and the motor 60 is stopped (step SP241), completing the series of initial position detection operations (step SP242), and the process transitions to normal control (step SP250).

<Operation flow for initial position detection (with sensor) (Pattern 3)>
After the main power is turned on (step SP201), when the origin sensor detects the operating part of the slider 30 ("operating part position = origin position W _op ") (step SP203), the operation flow proceeds according to pattern 3 (see FIGS. 33A and 33D). In pattern 3, the motor 60 is first driven in the forward direction (step SP231), moving the slider 30 in the direction protruding from the main body 10 (the direction of the nail-pulling operation), and the operation waits until the origin sensor becomes non-detecting (step SP232). If the non-detecting state is reached, the motor 60 is rotated in the reverse direction (step SP233), moving the slider 30 in the direction of retraction. The operation then waits until the origin sensor detects the operating part (step SP234). When the origin sensor detects the moving part, it determines that the moving part that has passed the origin position W _op has returned to the origin position W _op , stops the motor 60 (step SP241), and then completes the series of initial position detection operations in that state (step SP242), and transitions to normal control (step SP250).

<Operation flow of nail removal + initial position detection + clamp>
An initial position detection operation after the trigger is turned on may be added to the nail puller and clamping operation described above. An example of the operation flow in this case will be described (see Figures 38A to 38C). Note that the following description will focus on the differences from the nail puller and clamping operation flow described above (see Figures 36A to 36C).

In this operation flow, after the main power is turned on (step SP601), the initial position of the slider 30 is detected (step SP602). For initial position detection, in the sensorless case, the detection operation is performed as described in the "Operation flow for initial position detection (sensorless)" (see Figures 32A to 32D), and in the sensored case, the detection operation is performed as described in the "Operation flow for initial position detection (with sensor)" (see Figures 33A to 33D). Thereafter, the nail removal or clamping operation is performed (see Figures 38A to 38C), similar to the "Operation flow for nail removal + clamping" (see Figures 36A to 36C) described above.

The above-described embodiment is one preferred example of the present invention, but is not limited to this and various modifications are possible without departing from the spirit of the present invention. For example, in the above-described embodiment, a structure was described in which the hook member 20 (the hook 22) is moved relatively by sliding only the slider 30 (a structure in which the hook 22 is fixed relatively to the main body 10), but a structure in which both the slider 30 and the hook member 20 are moved simultaneously may also be used. Although not specifically shown here, for example, a rack-and-pinion mechanism or the like may be used to link the slider 30 and the hook member 20, or a linkage mechanism that links the slider 30 to the protruding movement of the slider 30 may be used to cause the hook member 20 to slide in the opposite direction.

In the above embodiment, a rechargeable nail puller 1 using a motor 60 as its drive source was described (see Figure 6B, etc.), but this is merely one example of a suitable configuration. Although not specifically illustrated, various power-driven nail pullers, such as electric nail pullers that use a motor as their drive source, compressed air nail pullers that use an air motor, and hydraulic nail pullers that use a hydraulic motor, as well as various power tools that use an AC electric motor as their drive source, can be configured. Alternatively, the slider 30 can be driven by an air cylinder, or the drive mechanism 70 can be configured using a trapezoidal screw instead of the ball screw 73. Alternatively, a rack and pinion, worm gear, or the like can be used to convert the rotation of the motor 60 into linear motion.

The present invention is suitable for use in various power tools, including electric nail pullers.

1...Chargeable nail puller (power tool)
10... Main body portion 11... Mechanical portion 12... Hand grip (grip portion)
13... Battery storage section 13S... Placing surface 14... Main frame (guiding member)
15...frame base 20...hook member (engagement member, guide member)
21... Rotatable portion of hook member (rotatable portion of engagement member)
22...Hook (engagement portion)
22'... Hook 23... Cylindrical portion 24... Fastening screw 26... O-ring (resistor)
30...Slider (sliding member)
31...Slider tip (sliding member tip)
31f...flat surface 32...slider rod portion 32a...flange portion 32b...internal thread 32c...sleeve portion 33...slider side cover portion 34...slider rotatable portion (sliding member rotatable portion)
35...Slider protruding leg (holding portion)
36...Tapered portion (pointed portion) of protruding leg of slider
36a...Tip of tapered portion (tip of pointed portion)
36b...lower surface of tapered portion 36t...upper surface of tapered portion 37...striked portion 38...O-ring (resistor)
40: Slider attachment 50: Cover 60: Motor (drive source)
66... Battery 70... Drive mechanism 71... Reducer (part of the drive mechanism)
72...Screw shaft 72'...Screw shaft 73...Ball screw (part of the drive mechanism)
80...Origin sensor (sensor that detects the position of the slider)
90...Control device 92...Mode operation/display unit 122...Trigger switch 132...Strap 134...Belt hook 300...Hammer 400...Press-down tool C1...Threshold current C2 during reverse drive in nail pull mode...Threshold current DA during reverse drive in clamp mode...Drive shaft L1...Length Los corresponding to the internal space required for the stroke of the hook member...Offset amount L2 of hook...Height of mechanism unit in initial position (retracted state) L3...Length L4 from drive shaft DA to the front end of the flat surface...Horizontal length L5 from drive shaft DA to the tip of the hook...Horizontal length P from the tip of the hook to the tip of the protruding leg...Nail (work object)
Pc: Virtual center axis when nail P is assumed to be straight Ph: Nail head Pt: Nail foot Q: Concrete panel (work object)
R... Crosspiece (work object)
U... (user) user VP... virtual plane including the drive shaft W ₀ ... target initial position W ₁ ... reverse limit position W ₂ ... forward limit position W _op ... origin position X ₀ ... initial position setting specified amount X ₁ ... specified amount X ₂ ... specified amount X _ap ... abnormality prevention specified amount

Claims (11)

An electric tool used for work such as nail removal,
a main body;
an engaging member provided on the main body portion side and having an engaging portion that engages with a part of a work object;
a sliding member that moves in and out of the main body portion to move a part of the sliding member toward and away from the engaging member;
a drive source for operating the sliding member;
It is equipped with
a tapered pointed portion is formed on a part of the sliding member, the pointed portion facing in a direction perpendicular to a drive shaft that passes through the sliding member and extends along the sliding direction of the sliding member;
The engaging member has an engaging portion formed thereon that protrudes from the drive shaft in the same direction as the pointed portion of the sliding member ,
The power tool , wherein the engaging member and the pointed portion are rotatable around the drive shaft . The power tool of claim 1, wherein the pointed portion has a tapered shape facing away from the drive shaft. The power tool according to claim 2, wherein the pointed portion is shaped so that its tip is positioned outside the engaging portion of the engaging member relative to the drive shaft. The power tool according to claim 3, wherein the pointed portion is larger than the engaging member. The power tool according to claim 4, wherein the pointed portion has an outline laid out outside the outline of the engaging member. The power tool according to claim 4 or 5, wherein a plurality of pointed portions are formed and spaced apart to accommodate the engaging portion. The power tool according to claim 6, wherein the multiple pointed portions are formed symmetrically about a plane including the drive shaft. The power tool described in any one of claims 1 to 7, wherein the pointed portion is formed on a detachable attachment that forms part of the sliding member. The power tool according to claim 8, wherein a striking portion is formed on the side of the attachment opposite the pointed portion. The power tool according to claim 9, wherein the striking portion is formed in a shape that protrudes toward the side opposite the pointed portion. The power tool described in any one of claims 8 to 10, wherein the attachment is made of metal.