JP2022082223A - Impact tool - Google Patents

Abstract

To provide an impact tool which is excellent in handleability and enables improvement of efficiency of driving work.SOLUTION: An electric hammer 50 includes: a housing 50a which houses a motor 54 and has a handle part 58; a battery pack 66 which is detachably attached to the housing 50a; and a striking mechanism 53 which is operated by driving the motor 54. The electric hammer 50 includes an adapter 1 for driving a drift pin (a drift pin driving mechanism) comprising: a shaft 2 which is disposed in front of the striking mechanism 53 and to which an impact is transmitted by the striking mechanism 53; a sleeve 3 which is installed on the shaft 2 so as to be movable relative to the shaft 2 in an anteroposterior direction with predetermined strokes and in which a rear end 101 of a drift pin 100 may be inserted into a front end; and a coil spring 4 which biases the sleeve 3 to an advance position located at a front end of the stroke.SELECTED DRAWING: Figure 1

Description

The present invention relates to a striking tool used to drive a drift pin into a wood joint or the like.

In wooden construction, there is known a method of joining woods to each other by attaching metal fittings to one piece of wood and driving a drift pin into the other piece of wood to penetrate the metal fittings. The operator uses a mallet to drive the drift pin, but if the number of pins is large, it takes time and the burden on the operator is large. Therefore, Patent Document 1 discloses an invention of a driving machine in which an adapter having a driving tip structure of a drift pin is attached to an air hammer. This adapter has a snap (shaft) attached to the air hammer, a guide (sleeve) that is attached to the snap and can move a predetermined stroke relative to each other, and a spring that is attached to the snap and the guide to urge the guide to the forward position. It is equipped with (coil spring).
Here, when the air hammer is driven with the rear end of the drift pin inserted into the tip of the guide protruding from the snap, the snap is continuously hit by the piston of the air hammer, and the drift pin is driven into the wood. When the snap advances by the stroke, the front end surface becomes the same surface as the front end surface of the guide, and the drift pin can be completely driven into the inside of the wood.

Japanese Unexamined Patent Publication No. 2008-161908

In the above-mentioned conventional driving machine, since an air hammer is used, it is necessary to prepare a compressor and a hose in addition to the air hammer. Therefore, it is troublesome to install and remove, and since it is connected to the hose, the maneuverability is deteriorated and the efficiency of the driving work may be lowered.

Therefore, it is an object of the present invention to provide a striking tool which is excellent in maneuverability and can improve the efficiency of driving work.

In order to achieve the above object, the present invention comprises a striking tool, a housing accommodating a motor and having a handle portion, and a housing.
A battery that can be attached to and detached from the housing,
The striking mechanism operated by the drive of the motor and
The shaft is located in front of the striking mechanism, and the striking mechanism transmits the striking. The sleeve is provided with a drift pin driving mechanism including a sleeve and a coil spring for urging the sleeve to a forward position which is a front end of the stroke.
Another aspect of the present invention is characterized in that, in the above configuration, at least a part of the handle portion is located behind the striking mechanism and on the axis of the shaft.
Another aspect of the present invention is characterized in that, in the above configuration, a driving end detecting means for detecting the completion of driving the drift pin into the material to be driven is provided.
In another aspect of the present invention, in the above configuration, the hitting end detecting means includes a sensor that non-contactly measures the distance between the driven material and the housing that advances with the driving of the drift pin. It is characterized by.
Another aspect of the present invention is characterized in that, in the above configuration, when the driving completion of the drift pin is detected by the driving end detecting means, the driving of the motor is stopped.
In another aspect of the present invention, in the above configuration, the housing is connected to the drive side housing including the striking mechanism and the drift pin driving mechanism so as to be relatively movable with respect to the drive side housing with a predetermined front-rear stroke. An elastic means having a handle-side housing including the handle portion and urging the handle-side housing to a retracted position at the rear end of the front-rear stroke between the drive-side housing and the handle-side housing. It is characterized by being provided.
Another aspect of the present invention is characterized in that, in the above configuration, when the driving of the drift pin is started, the rotation speed of the rising edge of the motor gradually increases from a low state.
Another aspect of the present invention is characterized in that, in the above configuration, the motor is driven at a rotation speed including a plurality of constant rotation states that gradually increase.
Another aspect of the present invention is characterized in that, in the above configuration, a speed change mechanism capable of arbitrarily changing the rotation speed of the motor is provided.
Another aspect of the present invention is characterized in that, in the above configuration, the drift pin driving mechanism is a detachable adapter.

According to the present invention, by using a battery as a drive unit, it is possible to improve the maneuverability and improve the efficiency of driving work.
According to another aspect in which at least a part of the handle portion is located behind the striking mechanism and on the axis of the shaft, the drift pin can be easily pushed in, and the pressing force from the handle portion can be efficiently transmitted to the drift pin.
According to another embodiment provided with a driving end detecting means for detecting the completion of driving of the drift pin into the material to be driven, it is possible to quickly take measures such as stopping the driving of the motor when the driving is completed.
According to another aspect in which the end-of-striking means includes a sensor that non-contactly measures the distance between the material to be driven and the housing that advances with the driving of the drift pin, even if the end-of-striking means is provided, the work can be performed. It doesn't get in the way.
According to another aspect in which the drive of the motor is stopped when the driving completion of the drift pin is detected by the driving end detecting means, the driving is stopped after the driving is completed, which leads to the protection of the material to be driven.
The housing has a drive-side housing including a striking mechanism and a drift pin driving mechanism, and a handle-side housing that is movably connected to the drive-side housing with a predetermined front-rear stroke and includes a handle portion. According to another aspect in which an elastic means for urging the handle-side housing to a retracted position at the rear end of the front-rear stroke is provided between the handle-side housing and the handle-side housing, vibration generated by the striking mechanism and the drift pin driving mechanism is generated. It becomes difficult to transmit to the handle part, and the usability during work becomes good.
According to another aspect in which the rotation speed at the start of the motor is controlled to gradually increase from a low state when the driving of the drift pin is started, the impact at the start of driving is reduced.
According to another embodiment including a speed change mechanism capable of arbitrarily changing the rotation speed of the motor, the number of hits that is easy to work with can be selected, and the usability is improved.
According to another aspect in which the drift pin driving mechanism is a detachable adapter, the adapter can be easily maintained or replaced.

It is a central vertical sectional view of the electric hammer equipped with the drift pin driving adapter of Embodiment 1. FIG. It is an enlarged view of the adapter part for driving a drift pin. It is explanatory drawing which shows the driving completion state of a drift pin. In the explanatory view of the modified example in which the holding mechanism (magnet) of the drift pin is adopted, (A) shows the cross section of the magnet portion, and (B) shows the central vertical cross section. It is explanatory drawing of the modification example which adopted the holding mechanism (O-ring) of a drift pin. It is explanatory drawing of the change example which adopted the muffling mechanism. It is explanatory drawing of the modification which provided the protection part in the sleeve. It is explanatory drawing which shows the modification example of a stopper mechanism. In the explanatory view showing the modification example of the stopper mechanism, (A) shows the cross section of the detent pin portion, and (B) shows the side surface. It is explanatory drawing which shows the driving completion state of the drift pin in the modification example of a stopper mechanism. It is a central vertical sectional view (initial position) of the drift pin driving machine of the second form. It is an enlarged view (initial position) of the driving mechanism part. It is an enlarged view (hit position) of the driving mechanism part. It is an enlarged view of the driving mechanism part (the driving completed state).

Hereinafter, embodiments of the present invention will be described with reference to the drawings.
[Form 1]
FIG. 1 is a central vertical sectional view showing an example of a drift pin driving adapter (hereinafter referred to as “adapter”) 1 and an electric hammer 50 which is an example of a striking tool equipped with the adapter 1. FIG. 2 is an enlarged view of a portion of the adapter 1. Here, the left side will be described as the front.

(Explanation of the drift pin driving adapter)
The adapter 1 includes a shaft 2, a sleeve 3, and a coil spring 4.
The shaft 2 is made of metal having a circular cross section, and includes a front portion 5, an intermediate portion 6, and a rear portion 7. The front portion 5 and the rear portion 7 have the same diameter, and the intermediate portion 6 is formed to have a larger diameter than the front portion 5 and the rear portion 7. The front end surface 5a of the front portion 5 is a spherical surface that bulges forward. A flange 8 having a diameter larger than that of the intermediate portion 6 is formed between the front portion 5 and the intermediate portion 6. A detent pin 9 is driven into the intermediate portion 6 in the radial direction. A disk-shaped stopper 10 having a diameter larger than that of the flange 8 is externally mounted on the rear portion 7. The stopper 10 is axially fixed by a circlip 11 that engages with the rear portion 7 at a position where it abuts on the rear end of the intermediate portion 6. On the outer periphery of the rear end of the rear portion 7, a pair of grooves 12 and 12 extending forward from the rear end surface and a pair of recesses 13 and 13 extending in the front-rear direction are aligned with each other by 90 °. It is formed at a point-symmetrical position centered on L.

The sleeve 3 is a metal cylinder into which the shaft 2 is loosely inserted, and a small diameter hole 15 is coaxially formed in the front portion and a large diameter hole 16 is coaxially formed in the rear portion. In the middle portion of the small diameter hole 15, a narrower diameter portion 17 into which the front portion 5 of the shaft 2 is loosely inserted is formed in a ring shape. The small diameter hole 15 on the front side of the throttle portion 17 is a tapered hole portion 18 whose diameter increases toward the front.
The large diameter hole 16 has a diameter that allows the flange 8 of the shaft 2 to be loosely inserted. A metal inner sleeve 19 is press-fitted from the rear into the large-diameter hole 16 behind the flange 8 to prevent the flange 8 from coming off. The inner sleeve 19 has a flange portion 20 at the rear end that abuts on the rear surface of the sleeve 3 in a press-fitted state. On the inner circumference of the inner sleeve 19, an engaging groove 21 with which the detent pin 9 provided in the intermediate portion 6 is engaged is formed over the entire length in the axial direction. By engaging the detent pin 9 with the engaging groove 21, the shaft 2 and the sleeve 3 are restricted from rotating with each other. Further, the sleeve 3 has a stroke between the forward position where the inner sleeve 19 abuts on the flange 8 and the retracted position where the step portion 22 formed between the small diameter hole 15 and the large diameter hole 16 abuts on the flange 8. Then, it becomes possible to move relative to the shaft 2 back and forth.

The coil spring 4 is exteriorized on the front portion 5 inside the sleeve 3. The front end of the coil spring 4 is in contact with the throttle portion 17, and the rear end of the coil spring 4 is in contact with the flange 8.
Therefore, the sleeve 3 is normally urged by the coil spring 4 to the forward position where the inner sleeve 19 abuts on the flange 8. At this forward position, the front end surface 5a of the front portion 5 of the shaft 2 is located in front of the throttle portion 17 and protrudes into the tapered hole portion 18.
At the forward position of the sleeve 3 shown in FIG. 2, the axial distance D1 between the front end surface of the stopper 10 and the rear end surface of the inner sleeve 19 is the axial distance between the front end surface 5a of the shaft 2 and the front end surface of the sleeve 3. It is equal to D2. Further, the distance D1 is also equal to the axial distance D3 between the step portion 22 and the front end surface of the flange 8.

(Explanation of electric hammer)
The electric hammer 50 includes a main body housing 51 and a motor housing 52 as the housing 50a. The main body housing 51 accommodates the striking mechanism 53 and extends in the front-rear direction, which is the striking axis direction. The motor housing 52 is integrally coupled to the lower side of the main body housing 51 and houses a brushless motor 54 with the output shaft 55 facing upward. The output shaft 55 projects into the main body housing 51.
Further, the electric hammer 50 further includes an outer housing 56 and a handle housing 57 as the housing 50a. The outer housing 56 extends in the front-rear direction and covers the outside of the main body housing 51. The handle housing 57 is integrally coupled to the rear side of the outer housing 56, and is provided from the rear of the outer housing 56 to the lower side of the motor housing 52.

The handle housing 57 includes a handle portion 58, a battery mounting portion 59, and a controller accommodating portion 60. The handle portion 58 extends in the vertical direction and has a connecting portion 61 on the front side which is connected to the rear end of the outer housing 56 and covers the rear portion of the main body housing 51 from the rear. The handle portion 58 includes a switch 62 and a switch lever 63. The battery mounting portion 59 is formed at the lower end of the handle portion 58. The controller accommodating portion 60 is formed so as to be continuous with the front side of the battery mounting portion 59 and wrap around to the lower side of the motor housing 52. A locking portion 64 is formed rearward at the upper end of the front surface of the controller accommodating portion 60. A locking recess 65 for locking the locking portion 64 from the front is formed at the lower end of the front surface of the motor housing 52.
A battery pack 66, which is a power source, can be slidably mounted on the battery mounting portion 59 from the rear. The battery mounting portion 59 is provided with a terminal block 67 to which the battery pack 66 is electrically connected.
In the controller accommodating portion 60, the controller 68 provided with the control circuit board is accommodated in an inclined posture in which the front portion is lower than the rear portion.

The striking mechanism 53 includes a cylindrical tool holder 70 and a cylinder 71. The tool holder 70 is held on the front side of the main body housing 51 and extends in the front-rear direction. The cylinder 71 is held on the rear side of the main body housing 51 and extends coaxially with the tool holder 70 in the front-rear direction.
A crank shaft 72 is supported in the vertical direction on the rear side of the cylinder 71 in the main body housing 51. An eccentric pin 73 is provided upward on the upper portion of the crank shaft 72, and a gear 74 is provided on the lower portion of the crank shaft 72. The gear 74 meshes with a pinion 75 provided at the upper end of the output shaft 55.
A piston 76 is housed in the cylinder 71 so as to be movable back and forth. The piston 76 is connected to the eccentric pin 73 via a connecting rod 77. In the cylinder 71, in front of the piston 76, the striker 79 is accommodated so as to be movable back and forth via the air chamber 78. An impact bolt 80 is provided in the tool holder 70 in front of the striker 79. At the front end of the tool holder 70, a pair of balls 81, 81 that engage with the recesses 13, 13 provided in the rear portion 7 of the adapter 1 are provided. The front end of the tool holder 70 is provided with an operation sleeve 82 that is urged forward to maintain the engagement state of the balls 81 and 81 with the recesses 13 and 13.

The outer housing 56 and the handle housing 57 are provided so as to be relatively movable back and forth with respect to the main body housing 51 and the motor housing 52.
A first coil spring 83 is provided in the front-rear direction between the main body housing 51 and the handle portion 58. Both ends of the first coil spring 83 are exteriorized in the connecting portion 61 so as to straddle the front boss 84 and the rear boss 85 provided on the rear surface of the main body housing 51 and the front surface of the handle portion 58, respectively. The first coil spring 83 may be one, or a plurality of first coil springs 83 may be arranged side by side in the left-right direction.
A second coil spring 86 is also provided between the motor housing 52 and the controller housing portion 60. On the lower surface of the motor housing 52, a protruding piece 87 that projects downward into the controller housing portion 60 is provided. In the controller accommodating portion 60, a receiving rib 88 erected behind the projecting piece 87 is provided. The second coil spring 86 is held in the front-rear direction between the projecting piece 87 and the receiving rib 88.
The outer housing 56 and the handle housing 57 are normally retracted in FIG. 1 in which the locking portion 64 of the controller accommodating portion 60 abuts on the locking recess 65 of the motor housing 52 due to the urging of the first and second coil springs 83 and 86. It is elastically urged to the position.

A speed change dial 89 is provided behind the motor 54 and below the motor housing 52. The controller 68 drives the motor 54 at a rotation speed (number of hits) selected by the rotation operation of the speed change dial 89.
A sensor 90 is provided forward in front of the motor 54 and above the motor housing 52. The sensor 90 irradiates the laser beam forward, receives the reflected light, and measures the distance to the object. The measurement signal is input to the controller 68.
A light 91 that illuminates the front of the tool holder 70 is provided below the motor housing 52 and in front of the controller housing 60.

(Drift pin driving)
In the adapter 1 and the electric hammer 50 configured as described above, the operation sleeve 82 is retracted at the front end of the tool holder 70 to release the pressing of the balls 81 and 81. In this state, the rear portion 7 of the shaft 2 of the adapter 1 is inserted into the front end of the tool holder 70 instead of the bit. At this time, if a pair of ridges (not shown) is formed on the inner peripheral surface of the tool holder 70, the grooves 12 and 12 of the rear portion 7 are inserted in the phase of the ridges. Then, the recesses 13 and 13 are located inside the balls 81 and 81, respectively, and when the operation sleeve 82 is released from the retreat and advanced, the operation sleeve 82 presses the balls 81 and 81 toward the axial center of the tool holder 70. .. Therefore, the balls 81 and 81 are fitted in the recesses 13 and 13 and the shaft 2 is mounted in a state where the shaft 2 is prevented from coming off and rotating. However, the shaft 2 can move back and forth with a stroke in which the balls 81 and 81 move relative to each other in the recesses 13 and 13.

If there is no protrusion on the inner peripheral surface of the tool holder 70, even if the rear portion 7 of the shaft 2 is inserted into the tool holder 70 and the operation sleeve 82 is advanced, the phases of the balls 81 and 81 and the recesses 13 and 13 are matched. May not be. In this case, if the adapter 1 is rotated, the pressed balls 81, 81 will be fitted into the recesses 13, 13. Here, since the shaft 2 is integrated with the sleeve 3 in the rotation direction via the detent pin 9 and the inner sleeve 19, if the sleeve 3 is gripped and rotated, the shaft 2 also follows and rotates. Therefore, the balls 81 and 81 can be easily fitted into the recesses 13 and 13 by rotating the shaft 2 by operating the sleeve 3 without directly gripping the shaft 2.

In this way, the handle portion 58 of the electric hammer 50 with the adapter 1 attached to the tool holder 70 is gripped, and the tapered hole portion 18 of the sleeve 3 is provided with the front end at the driving position of the material W to be driven, as shown in FIGS. It covers the rear end 101 of the drift pin 100 inserted shallowly. Then, the rear end 101 of the drift pin 100 is accommodated in the tapered hole portion 18 and abuts on the front end surface 5a of the shaft 2, and the shaft 2 is aligned substantially linearly with the drift pin 100. Here, when the electric hammer 50 is pushed forward by the hand gripping the handle portion 58, the shaft 2 moves relative to the rear in the tool holder 70, and the balls 81 and 81 are engaged with the front ends of the recesses 13 and 13 while being engaged with each other. The rear portion 7 comes into contact with the impact bolt 80. Subsequently, the outer housing 56 and the handle housing 57 advance against the urging force of the first and second coil springs 83 and 86.

Then, when the switch lever 63 is pushed in to turn on the switch 62, the controller 68 drives the motor 54. However, the controller 68 does not drive the motor 54 at the rotation speed set by the speed change dial 89 from the start, and executes a soft start in which the rotation speed is gradually increased from a low rotation speed for a predetermined time at the start-up. The motor 54 is driven at the set rotation speed.
A lock-on button 92 for holding the switch lever 63 at the pushed position is provided on the upper portion of the handle portion 58. Therefore, if the lock-on button 92 is pushed in while the switch lever 63 is pushed in, the motor 54 continues to be driven even if the switch lever 63 is not kept pushed.

When the output shaft 55 of the motor 54 rotates, the crank shaft 72 rotates via the pinion 75 and the gear 74. Therefore, the piston 76 moves back and forth via the connecting rod 77. As a result, the striker 79 moves back and forth in conjunction with each other via the air chamber 78. The striker 79 moves back and forth to hit the impact bolt 80 and indirectly hit the shaft 2. Therefore, the drift pin 100 is driven into the material W to be driven. At this time, since the spherical front end surface 5a of the shaft 2 abuts on the rear end 101 of the drift pin 100, the impact is always transmitted to the axial center of the drift pin 100. Further, even if the adapter 1 is shaken, the deviation from the drift pin 100 can be absorbed in the tapered hole portion 18, so that the impact on the drift pin 100 is efficiently transmitted.
At the time of driving, the hand gripping the handle portion 58 is located rearward on the axis L of the shaft 2 (the axis of the tool holder 70). Therefore, the forward pressing force by the operator is transmitted to the shaft 2 without loss. Further, the outer housing 56 and the handle housing 57 advance against the urging force of the first and second coil springs 83 and 86 and do not come into contact with the main body housing 51 and the motor housing 52. Therefore, the vibration transmitted to the outer housing 56 and the handle housing 57 at the time of driving is suppressed, and the vibration transmitted to the hand holding the handle portion 58 is reduced.

When the electric hammer 50 and the adapter 1 move forward as the driving progresses, the front end of the sleeve 3 comes into contact with the surface of the material W to be driven. Then, the sleeve 3 remains as it is, and the shaft 2 advances while continuing to drive. Therefore, as shown in FIG. 3, the stopper 10 comes into contact with the flange portion 20 of the inner sleeve 19. At this time, the flange 8 also comes into contact with the step portion 22, and the front end surface 5a is in the same front-rear position as the front end surface of the sleeve 3. In this way, the rear end surface of the drift pin 100 becomes flush with the surface of the material to be driven W, and is in a state of being completely driven into the material W to be driven.
When the operator visually observes that the stopper 10 has come into contact with the flange portion 20 of the inner sleeve 19 and releases the pushing of the electric hammer 50, the driving work is completed.
However, instead of visual inspection by the stopper 10, the controller 68 is made to monitor the measurement signal by the sensor 90, and it is determined from the measurement signal that the distance from the material to be driven W has reached the driving completion distance of the drift pin 100. , The controller 68 may determine that the driving is completed and stop the driving of the motor 54.
During the driving operation, the operator can support the adapter 1 with the other hand, but since the coil spring 4 is inside the sleeve 3 and the entire sleeve 3 is exposed, it is easy to grip the sleeve 3. Can be supported. In addition, there is less possibility that foreign matter such as wood chips generated from the material W to be driven enters the inside.

(Effect of the invention relating to the adapter and the electric hammer equipped with the adapter)
The adapter 1 and the electric hammer 50 of the above embodiment 1 are externally mounted so as to be relatively movable in the front-rear direction with respect to the shaft 2 capable of hitting the drift pin 100 and the shaft 2 with a predetermined stroke, and the rear end of the drift pin 100 is at the front end. It includes a sleeve 3 into which the 101 can be inserted, and a coil spring 4 that urges the sleeve 3 to a forward position which is the front end of the stroke. The coil spring 4 is arranged inside the sleeve 3.
With this configuration, foreign matter does not get caught and hinder the relative movement of the sleeve 3, and the coil spring 4 is not damaged by an external impact, so that good operability and durability can be maintained. Further, since the sleeve 3 can be reliably gripped, it is also excellent in usability.

The adapter 1 is provided with a detent pin 9 and an engagement groove 21 (detent mechanism) that regulate the relative rotation of the shaft 2 and the sleeve 3 with each other. Therefore, the sleeve 3 can be held and the shaft 2 can be rotated when the electric hammer 50 is attached to and detached from the electric hammer 50, and the phase matching can be easily performed.
The front end of the sleeve 3 into which the rear end 101 of the drift pin 100 is inserted is formed with a tapered hole portion 18 having a tapered shape whose diameter increases toward the front. Therefore, the runout of the adapter 1 at the time of driving can be tolerated, and the rear end 101 of the drift pin 100 can be smoothly guided into the sleeve 3.
A stopper 10 and an inner sleeve 19 (stopper mechanism) for restricting the advancement of the shaft 2 when the drift pin 100 has been driven into the material W to be driven are visually provided. Therefore, the operator can easily confirm that the drift pin 100 has been driven.

In the invention relating to the adapter and the electric hammer to which the adapter is attached, the detent mechanism between the shaft and the sleeve may be formed between the shaft and the sleeve by omitting the inner sleeve. For example, it is conceivable to form a key on one of the shaft and the sleeve and a keyway on the other, or to spline the other.
The stopper mechanism can be changed as appropriate, and the shape of the stopper itself can be changed, and the position of the stopper can be changed in the axial direction of the shaft.
In addition, the orientation and arrangement of the motor, the type of motor, the position of the controller, the position and number of battery packs, etc. may be changed. The striking tool is not limited to a DC tool using a battery pack as a power source, and may be an AC tool using a commercial power source or an air tool. A hammer drill can be used instead of an electric hammer.

(Effect of the invention relating to an electric hammer using a battery pack)
The electric hammer 50 of the first embodiment includes a housing 50a that houses the motor 54 and has a handle portion 58, a battery pack 66 (battery) that can be attached to and detached from the housing 50a, and a striking mechanism 53 that is operated by driving the motor 54. I have. Further, the electric hammer 50 is arranged in front of the striking mechanism 53, and is exteriorized so as to be relatively movable in the front-rear direction with respect to the shaft 2 to which the striking is transmitted by the striking mechanism 53 and the shaft 2 with a predetermined stroke, and at the front end. An adapter 1 (drift pin driving mechanism) including a sleeve 3 into which the rear end 101 of the drift pin 100 can be inserted and a coil spring 4 for urging the sleeve 3 to a forward position which is the front end of the stroke is provided.
By using the battery pack 66 as the drive unit in this way, it is possible to improve the maneuverability and improve the efficiency of the driving work.

Since the upper portion of the handle portion 58 is located behind the striking mechanism 53 on the axis L of the shaft 2, it is easy to push the drift pin 100, and the pushing pressure from the handle portion 58 is efficiently transmitted to the drift pin 100. Can be done.
It is provided with a sensor 90 and a controller 68 (means for detecting the end of driving) for detecting the completion of driving the drift pin 100 into the material W to be driven. Therefore, it is possible to quickly take measures such as stopping the driving of the motor 54 when the driving is completed.
The driving end detecting means includes a sensor 90 that non-contactly measures the distance between the material W to be driven and the housing 50a that moves forward with the driving of the drift pin 100. Therefore, even if the hitting end detecting means is provided, it does not interfere with the work.
When the driving completion of the drift pin 100 is detected by the driving end detecting means, the driving of the motor 54 is stopped. Therefore, it is not hit after the driving is completed, which leads to the protection of the material W to be driven.

The housing 50a is connected to the main body housing 51 and the motor housing 52 (driving side housing) including the striking mechanism 53 and the adapter 1 so as to be relatively movable with a predetermined front-rear stroke to the main body housing 51 and the motor housing 52. It has an outer housing 56 including 58 and a handle housing 57 (handle side housing). Then, between the main body housing 51 and the motor housing 52, and the outer housing 56 and the handle housing 57, the outer housing 56 and the handle housing 57 are urged to the retracted position which is the rear end of the front-rear stroke. 83,86 (elastic means) are provided.
Therefore, the vibration generated by the striking mechanism 53 and the adapter 1 is less likely to be transmitted to the handle portion 58, and the usability during work is improved.

When the driving of the drift pin 100 is started, the rotation speed of the rising edge of the motor 54 is controlled so as to gradually increase from a low state. Therefore, the impact at the start of driving is reduced.
It is equipped with a speed change dial 89 and a controller 68 (speed change mechanism) that can arbitrarily change the rotation speed of the motor 54. Therefore, it is possible to select the number of hits that is easy to work with, and the usability is good.
The drift pin driving mechanism is a detachable adapter 1. Therefore, maintenance and replacement of the adapter 1 can be easily performed.

In the invention relating to the electric hammer using the battery pack, not only the non-contact type sensor but also a contact type sensor can be used as the hitting end detecting means. For example, if a stopper pole protruding forward is attached to the housing, the driving is completed at the timing when the stopper pole abuts on the surface of the material to be driven. It is desirable that the stopper pole can change the amount of protrusion to the front.
When the driving is completed, the control is not limited to the control of stopping the drive of the motor, but the control of lowering the rotation speed of the motor may be performed.
The control of the motor from the start of driving is not limited to the soft start, and may be performed at a constant rotation from the beginning, or may be driven at a rotation speed including a plurality of constant rotation states that gradually increase. .. Further, the number of revolutions may be increased according to the load on the motor and the vibration at the time of impact.
The control of these motors may be set in the controller as the driving mode and can be selected by the operator on the operation panel or the like.

The speed change mechanism is not limited to the one using the speed change dial, and may be a speed change mechanism based on the pushing amount of the switch lever.
The position of the handle portion located on the axis of the shaft does not have to be the upper part of the handle portion.
In addition, the orientation and arrangement of the motor, the type of motor, the position of the controller, the position and number of battery packs, etc. may be changed as appropriate. A hammer drill can be used as a striking tool instead of an electric hammer.

(Explanation of adapter change example)
Next, an example of changing the adapter common to each invention will be described.
In FIG. 4, a magnet 25 exposed in the small diameter hole 15 is provided at the front end of the sleeve 3 as a holding mechanism for holding the rear end 101 of the drift pin 100. The rear end 101 of the drift pin 100 inserted into the small diameter hole 15 is attracted to the magnet 25, so that the rear end 101 is held.
In this way, if the magnet 25 capable of holding the rear end 101 of the inserted drift pin 100 is provided at the front end of the sleeve 3, the drift pin 100 is less likely to fall off from the sleeve 3 and the workability is good. Become.
The shape of the magnet is not limited to this, and may be another shape such as a ring shape or a C shape, or a plurality of magnets may be arranged. Further, although the front end of the small diameter hole is not tapered here, it may be tapered as long as the drift pin can be attracted.
FIG. 5 shows an O-ring 26 held on the inner circumference of the tip of the small diameter hole 15 as a holding mechanism. The O-ring 26 holds the rear end 101 of the drift pin 100 inserted into the small diameter hole 15. Therefore, the drift pin 100 is less likely to fall off from the sleeve 3, and workability is improved.
The number of O-rings is not limited to one, and a plurality of O-rings may be arranged side by side in the axial direction. Elastic rings other than O-rings can also be used. It can also be combined with a magnet.

In FIG. 6, a ring groove 27 is formed on the inner peripheral surface of the throttle portion 17 of the sleeve 3 to hold an O-ring 28 that is in sliding contact with the front portion 5. Further, a ring groove 29 is formed on the outer peripheral surface of the flange 8 to hold an O-ring 30 that is in sliding contact with the large-diameter hole 16.
The shaft 2 is elastically supported in the sleeve 3 by the O-rings 28 and 30. Therefore, the shaft 2 is less likely to come into contact with the sleeve 3, and the sound when the drift pin 100 is driven can be reduced.
The number of O-rings is not limited to one, and a plurality of O-rings may be arranged side by side in the axial direction. Elastic rings other than O-rings can also be used.
In FIG. 6, at the same time, the sleeve 3 is made of resin, and the outer circumference of the sleeve 3 is covered with a sound absorbing sponge 31. Therefore, even if the shaft 2 comes into contact with the sleeve 3, the generated sound is reduced, and the generated sound is also absorbed by the sound absorbing sponge 31 and reduced.

If such a muffling mechanism is provided, the sound at the time of driving is effectively reduced. However, it is not necessary to apply all of the elastic support of the shaft, the resin molding of the sleeve, and the sound absorbing sponge at the same time, and only one of them may be applied, or only two of them may be applied. .. Other muffling mechanisms can also be adopted.

FIG. 7 shows an example in which a resin or rubber protective portion 32 is provided on the front end surface of the sleeve 3. The protective portion 32 can protect the surface of the material to be driven W when the sleeve 3 comes into contact with the sleeve 3.
The shape of the protective portion can be changed as appropriate, and materials having different types and physical characteristics may be laminated in the front-rear direction. Even when the entire sleeve 3 is made of resin as shown in FIG. 6, the front end surface serves as a protective portion.

8 and 9 show an example in which the stopper 10A has a cylindrical shape including a rear cylinder 33 and a front cylinder 34 that expands from the rear cylinder 33 and opens forward. The rear cylinder 33 is connected to the rear portion 7 of the shaft 2 by a pin 35. The front cylinder 34 has a structure that is externally attached to the rear end of the sleeve 3 from the rear. On the outer peripheral surface of the sleeve 3, a stopper portion 36 that the front cylinder 34 comes into contact with when the distance D1 advances is provided around the outer peripheral surface.
The inner sleeve 19 does not have a flange portion, and the entire sleeve 3 is press-fitted into the sleeve 3 so that both ends of the detent pin 37 penetrating the intermediate portion 6 of the shaft 2 are engaged with the pair of engaging grooves 21 and 21. I'm letting you. Therefore, the shaft 2 and the sleeve 3 are restricted from rotating with each other.
In this case, when the driving of the drift pin 100 is completed, as shown in FIG. 10, the front cylinder 34 of the stopper 10A covers the rear end of the sleeve 3 from the outside and comes into contact with the stopper portion 36. Therefore, the operator can visually check the completion of driving. At this time, the rear end surface of the sleeve 3 comes into contact with the front surface of the rear cylinder 33 in the front cylinder 34.
In this way, the stopper mechanism is integrally attached to the shaft 2 so as to be movable back and forth, and is used as a stopper 10A (stopper member) that comes into contact with the rear end of the sleeve 3 when the driving is completed. It has a tubular shape that covers the outer circumference and overlaps in the radial direction. Therefore, the space between the sleeve 3 and the stopper 10A is blocked, and the possibility that foreign matter such as wood chips intrudes into the adapter 1 is reduced.

[Form 2]
In the above embodiment, the separate adapter 1 is attached to the existing electric hammer 50, but it can also be a striking tool dedicated to the drift pin, which is integrally provided at the tip with the function of the adapter as a driving mechanism. .. Hereinafter, a drift pin driving machine (hereinafter referred to as a “driving machine”), which is an example of this striking tool, will be described. However, the same components as those of the adapter 1 and the electric hammer 50 of the first embodiment are designated by the same reference numerals, and duplicate description will be omitted.
(Explanation of the driving machine)
A driving mechanism 1A is provided at the tip of the driving machine 50A shown in FIG. In the driving mechanism 1A, the shaft 2A is loosely inserted in the front end portion 95 of the tool holder 70 extended forward so as to be movable back and forth, as shown in FIG. The shaft 2A includes a front portion 5 in which the front end surface 5a is a spherical surface, and a rear portion 7 having recesses 13 and 13. The front end portion 95 is provided with a pair of engaging pins 96, 96 that are loosely inserted from the outside in the radial direction and whose tip engages with the recesses 13, 13. The outer diameter of the front end portion 95 gradually increases toward the rear so as to be from the tip to the small diameter portion 97, the middle diameter portion 98, and the large diameter portion 99. The engaging pins 96, 96 are arranged in the middle diameter portion 98.

A sleeve 3A is externally attached to the front end portion 95. The sleeve 3A coaxially includes a small diameter hole 40 on the front side that is exteriorized by the small diameter portion 97 and a large diameter hole 41 on the rear side that is exteriorized by the medium diameter portion 98. A tapered hole portion 18 having a larger diameter toward the rear is formed on the front side of the small diameter hole 40, and the rear end of the tapered hole portion 18 is a front stopper 42 having a smaller diameter than the small diameter hole 40.
A pair of slits 43, 43 in the front-rear direction communicating with the large-diameter hole 41 are formed in the rear portion of the sleeve 3A, and the engaging pins 96, 96 are loosely inserted into the slits 43, 43 so as to be relatively movable. An outer sleeve 44 is exteriorized at the rear of the sleeve 3A on the outside of the slits 43 and 43. The outer sleeve 44 is positioned in the front-rear direction between the flange portion 45 formed at the rear end of the sleeve 3A and the locking ring 46 locked to the sleeve 3A. The outer sleeve 44 prevents the engaging pins 96, 96 from coming off radially outward. A ring-shaped rear stopper 47 is formed on the outer peripheral surface of the outer sleeve 44.

The coil spring 4 is externally attached to the small diameter portion 97 inside the sleeve 3A, and the front end abuts on the step portion 48 between the small diameter hole 40 and the large diameter hole 41, and the rear end is on the front surface of the medium diameter portion 98. It is in contact. The coil spring 4 urges the sleeve 3A to a forward position where the engagement pins 96, 96 are located at the rear ends of the slits 43, 43.
The front end of the main body housing 51 of the driving machine 50A is a cylindrical portion 93 exterior to the flange portion 45 at the forward position of the sleeve 3A.
At the forward position of the sleeve 3A, the axial distance D1 between the front end surface of the tubular portion 93 and the rear end surface of the rear stopper 47 of the outer sleeve 44 is the axis between the front end surface of the small diameter portion 97 and the rear end surface of the front stopper 42. It is equal to the distance D2 in the direction. The distance D1 is also equal to the axial distance D3 between the front end surface of the large diameter portion 99 and the rear end surface of the flange portion 45 of the sleeve 3A.

(Drift pin driving)
In the driving machine 50A configured as described above, the handle portion 58 is gripped and the tapered hole portion 18 of the sleeve 3A is shallowly inserted into the driving position of the material W to be driven, as shown in FIGS. 11 and 12. It covers the rear end 101 of the drift pin 100. Then, the rear end 101 of the drift pin 100 is accommodated in the tapered hole portion 18 and abuts on the front end surface 5a of the shaft 2A, and the shaft 2A is aligned substantially linearly with the drift pin 100. Here, when the driving machine 50A is pushed forward by the hand gripping the handle portion 58, the shaft 2A moves rearward in the tool holder 70 and the engaging pins 96 and 96 are moved rearward in the recess 13, as shown in FIG. While engaging with the front end of 13, the rear portion 7 comes into contact with the impact bolt 80. Subsequently, the outer housing 56 and the handle housing 57 advance against the urging force of the first and second coil springs 83 and 86.
Then, when the switch lever 63 is pushed in to turn on the switch 62, the controller 68 drives the motor 54. Here, too, the controller 68 executes a soft start and then drives the motor 54 at a set rotation speed.

When the output shaft 55 of the motor 54 rotates, the crank shaft 72 rotates via the pinion 75 and the gear 74. Therefore, the piston 76 moves back and forth via the connecting rod 77. As a result, the striker 79 moves back and forth in conjunction with each other via the air chamber 78. The striker 79 indirectly hits the shaft 2A via the impact bolt 80, so that the drift pin 100 is driven into the material W to be driven. At this time, since the spherical front end surface 5a of the shaft 2A abuts on the rear end 101 of the drift pin 100, the impact is always transmitted to the axial center of the drift pin 100. Further, since the hand gripping the handle portion 58 is located rearward on the axis L of the shaft 2A (the axis of the tool holder 70), the forward pressing force by the operator is transmitted to the shaft 2 without loss.
During the work, the outer housing 56 and the handle housing 57 advance against the urging force of the first and second coil springs 83 and 86 and do not come into contact with the main body housing 51 and the motor housing 52. Therefore, the vibration transmitted to the first outer housing 56 and the handle housing 57 at the time of driving is suppressed, and the vibration transmitted to the hand holding the handle portion 58 is reduced.

As the driving progresses, the driving machine 50A advances, and the front end of the sleeve 3A comes into contact with the surface of the material W to be driven. Then, the sleeve 3A remains as it is, and the shaft 2A advances while continuing to drive. Therefore, as shown in FIG. 14, the tubular portion 93 abuts on the rear stopper 47 of the outer sleeve 44, and the large diameter portion 99 abuts on the flange portion 45. At this time, the small diameter portion 97 also comes into contact with the front stopper 42, and the front end surface 5a is in the same front-rear position as the front end surface of the sleeve 3A. In this way, the rear end surface of the drift pin 100 becomes flush with the surface of the material to be driven W, and is in a state of being completely driven into the material W to be driven. Therefore, if the operator visually observes that the tubular portion 93 has come into contact with the rear stopper 47 of the outer sleeve 44 and releases the pushing of the driving machine 50A, the driving work is completed. The controller 68 monitors the measurement signal by the sensor 90, and when it is determined that the distance from the material to be driven W has reached the driving completion distance of the drift pin 100, the controller 68 stops driving the motor 54.
During the driving operation, the operator supports the sleeve 3A with the other hand, but since the coil spring 4 is inside the sleeve 3A and substantially the entire sleeve 3A is exposed, it is easy to grip the sleeve 3A. Can be supported by. In addition, there is less possibility that foreign matter such as wood chips generated from the material W to be driven enters the inside.

(Effect of the invention relating to the driving machine)
The driving machine 50A of the second embodiment is externally mounted so as to be relatively movable in the front-rear direction with a predetermined stroke with respect to the shaft 2A capable of striking the drift pin 100, and the rear end 101 of the drift pin 100 is inserted into the front end. A possible sleeve 3A and a coil spring 4 that urges the sleeve 3A to a forward position at the front end of the stroke are included, and the coil spring 4 provides a driving mechanism 1A (drift pin driving mechanism) arranged inside the sleeve 3A. Have at the tip. The driving machine 50A includes a striking mechanism 53 capable of striking the rear end of the shaft 2A, and a motor 54 (driving unit) for operating the striking mechanism 53.
With this configuration, foreign matter does not get caught and hinder the relative movement of the sleeve 3A, and the coil spring 4 is not damaged by an external impact, so that good operability and durability can be maintained. Further, since the sleeve 3A can be reliably gripped, the sleeve 3A is also excellent in usability.

Further, the driving machine 50A includes a housing 50a that houses the motor 54 and has a handle portion 58, a battery pack 66 (battery) that can be attached to and detached from the housing 50a, and a striking mechanism 53 that is operated by driving the motor 54. There is. Further, the driving machine 50A is arranged in front of the striking mechanism 53, and is exteriorized so as to be relatively movable in the front-rear direction with respect to the shaft 2A to which the striking is transmitted by the striking mechanism 53 and the shaft 2A with a predetermined stroke, and at the front end. It is provided with a driving mechanism 1A (drift pin driving mechanism) including a sleeve 3A into which the rear end 101 of the drift pin 100 can be inserted and a coil spring 4 for urging the sleeve 3A to a forward position which is the front end of the stroke.
By using the battery pack 66 as the drive unit in this way, it is possible to improve the maneuverability and improve the efficiency of the driving work.

A cylindrical portion 93 and a rear stopper 47 (stopper mechanism) for restricting the advancement of the shaft 2A when the driving of the drift pin 100 is completed are visually provided. Therefore, the operator can easily confirm that the drift pin 100 has been driven.
The stopper mechanism is integrally attached to the shaft 2A so as to be movable back and forth, and serves as a main body housing 51 (stopper member) that comes into contact with the outer sleeve 44 of the sleeve 3A when the driving is completed, and the front end of the main body housing 51 is the rear end of the sleeve 3A. The tubular portion 93 that overlaps in the radial direction is used. Therefore, the space between the sleeve 3A and the tubular portion 93 is closed, and the possibility that foreign matter such as wood chips invades into the driving mechanism 1A is reduced.
In addition, the same effect can be enjoyed in the second form for the same components as in the first form.

In the second form as well, as in the first form, a magnet, an O-ring, or the like may be provided at the front end of the sleeve to form a drift pin holding mechanism. The shaft can also be elastically supported in the sleeve in the radial direction.
As a sound deadening mechanism, the sleeve may be made of resin, or a sound absorbing sponge may be attached to the outer periphery. It is also possible to provide a protective portion at the front end of the sleeve to protect the surface of the material to be driven.
Further, the structure of the driving machine other than the driving mechanism can be changed in the same manner as the electric hammer of the first embodiment. The orientation and arrangement of the motor, the type of motor, the position of the controller, the position and number of battery packs, etc. may be changed.

1 ... Drift pin driving adapter, 1A ... Driving mechanism, 2,2A ... Shaft, 3,3A ... Sleeve, 4 ... Coil spring, 5 ... Front part, 5a ... Front end face, 6 ... Middle Part, 7 ... Rear, 8 ... Flange, 9,37 ... Anti-rotation pin, 10 ... Stopper, 13 ... Recessed, 14 ... Small diameter hole, 15 ... Large diameter hole, 18 ... Tapered hole , 19 ... Inner sleeve, 20, 45 ... Flange part, 21 ... Engagement groove, 25 ... Magnet, 26, 28, 30 ... O-ring, 31 ... Sound absorbing sponge, 32 ... Protection part, 33・ ・ Rear cylinder, 34 ・ ・ Front cylinder, 36 ・ ・ Stopper part, 40 ・ ・ Small diameter hole, 41 ・ ・ Large diameter hole, 42 ・ ・ Front stopper, 43 ・ ・ Slit, 44 ・ ・ Outer sleeve, 47 ・ ・Rear stopper, 50 ... Electric flange, 50a ... Housing, 50A ... Drift pin driving machine, 51 ... Main body housing, 52 ... Motor housing, 53 ... Impact mechanism, 54 ... Motor, 55 ... Output shaft , 56 ... outer housing, 57 ... handle housing, 58 ... handle, 62 ... switch, 63 ... switch lever, 68 ... controller, 70 ... tool holder, 83 ... first coil spring, 86 ... 2nd coil spring, 89 ... speed change dial, 90 ... sensor, 95 ... front end, 100 ... drift pin, 101 ... rear end, L ... shaft axis.

Claims (10)

A housing that houses the motor and has a handle,
A battery that can be attached to and detached from the housing,
The striking mechanism operated by the drive of the motor and
The shaft is located in front of the striking mechanism, and the striking mechanism transmits the striking. A drift pin driving mechanism including a sleeve and a coil spring that urges the sleeve to a forward position which is the front end of the stroke.
A striking tool characterized by being equipped with. The striking tool according to claim 1, wherein at least a part of the handle portion is located behind the striking mechanism on the axis of the shaft. The striking tool according to claim 1 or 2, further comprising a driving end detecting means for detecting the completion of driving the drift pin into the material to be driven. The striking tool according to claim 3, wherein the striking end detecting means includes a sensor that non-contactly measures the distance between the driven material and the housing that advances with the driving of the drift pin. .. The striking tool according to claim 3 or 4, wherein when the driving completion of the drift pin is detected by the striking end detecting means, the driving of the motor is stopped. The housing has a drive-side housing including the striking mechanism and the drift pin driving mechanism, and a handle-side housing including the handle portion, which is connected to the drive-side housing so as to be relatively movable with a predetermined front-rear stroke. The first aspect of the present invention is that an elastic means for urging the handle-side housing to a retracted position at the rear end of the front-rear stroke is provided between the drive-side housing and the handle-side housing. The striking tool according to any one of 5 to 5. The striking tool according to any one of claims 1 to 6, wherein when the driving of the drift pin is started, the rotation speed at the start of the motor gradually increases from a low state. The striking tool according to any one of claims 1 to 6, wherein the motor is driven at a rotation speed including a plurality of constant rotation states that gradually increase. The striking tool according to any one of claims 1 to 8, further comprising a speed change mechanism capable of arbitrarily changing the rotation speed of the motor. The striking tool according to any one of claims 1 to 9, wherein the drift pin driving mechanism is a detachable adapter.

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