JP3846551B2 - Electric tool - Google Patents

Description

[0001]
BACKGROUND OF THE INVENTION
The present invention relates to an electric tool such as an electric or hydraulic impact driver or an impact wrench, and particularly to an elastomer provided on the surface of a split housing.
[0002]
[Prior art]
A conventional power tool will be described with reference to FIGS. FIG. 7 is a side view showing a split housing 1 (hereinafter referred to as a housing) of the electric tool, and FIG. 8 is a schematic side view showing a working state in which elastomers 15 and 15a are provided on the surface of the housing 1.
[0003]
7 and 8, an impact driver or impact wrench having an outer frame such as a housing 1 and a hammer case has a substantially T shape, and a main body body portion 1b formed by the housing 1 has a drive source. Accommodates a motor, a speed reduction mechanism, and the like, and the handle 1c hanging from the main body body 1b accommodates a trigger switch for supplying power to the motor, a contact point electrically connected to a connection terminal of the storage battery, and the like. Has been. The hammer case disposed in contact with the housing 1 accommodates a striking mechanism for converting the rotational power of the motor into striking force and a tip tool holding portion such as a bit or a wrench (not shown).
[0004]
In such a configuration, the rotational power of the motor is transmitted from the pinion, which is the output shaft of the motor, to the speed reduction mechanism, and the rotational force and impact force are transmitted from the speed reduction mechanism to the tip tool via the impact mechanism. .
[0005]
The hammering mechanism includes a spindle, a hammer that is rotatable via a steel ball (steel ball) inserted in a cam groove formed in the spindle and movable in the axial direction of the rotary shaft, and a plurality of hammer claws provided on the hammer An anvil having an anvil claw that is struck and rotated by a spring and a spring that constantly biases the hammer toward the anvil side.
[0006]
The speed reduction mechanism has a fixed gear support jig, a fixed gear, a planetary gear, and a spindle supported by a rotation stopper in the housing 1, and a needle that serves as a rotation axis of the planetary gear supported by the spindle. It consists of pins.
[0007]
The pulse-like impact (impact) applied to the screw or nut that is tightened by the tip tool supplies power to the motor by operating the trigger switch, rotationally drives the motor, and the rotational power of this motor is connected to the tip of the motor. Is transmitted to the spindle through the planetary gear section (planetary gear planetary gear, fixed gear) through the pinion, and the rotational force of the spindle is transmitted through the steel ball disposed between the cam groove of the spindle and the hammer cam groove. The anvil is engaged with the anvil claw of the anvil and the anvil claw of the anvil which is transmitted to the hammer and is urged forward (on the tip tool side) by a spring arranged between the hammer and the planetary gear of the spindle. Rotates, so that a rotational force is applied to the tip tool. When the tightening torque of the screw or the like by the tip tool exceeds a predetermined value, the hammer pawls ride over the anvil pawl, so the engagement by both claws is temporarily released, that is, the hammer resists the spring when the tightening torque exceeds the predetermined value. Then move (retreat) to the motor side. Thereafter, the hammer is pushed back in the direction of the anvil by the compression force of the spring, and the hammer claw collides with the anvil claw to generate a striking force. By repeating the rotation and axial movement of the hammer in this way, continuous impact torque is applied to the tip tool.
[0008]
As described above, elastomers 15 and 15a are applied to the surfaces of the main body body portion 1b and the handle portion 1c formed by the housing 1, as shown in FIG. The elastomers 15 and 15a are formed by injecting molten elastomer from the two runners 16 'as shown in FIG. The purpose of providing the elastomers 15 and 15a is to prevent slipping to securely hold the electric tool, or to improve gripping comfort and improve operability and workability. Further, the impact when dropped on the ground. This is to prevent the electric tool from being damaged by absorbing the above, and to prevent the electric tool from slipping along the inclination when the electric tool is placed on the inclined surface.
[0009]
Therefore, the elastomers 15 and 15a are mainly provided in the main body body portion 1b and the handle grip portion 1c of the split housing 1. Further, by providing the elastomer 15 and the elastomer 15a at positions separated from each other, the electric power tool is held at two or more locations with respect to the ground plane.
[0010]
[Problems to be solved by the invention]
As described above, when the elastomer is molded on the surface of the split housing, the melted elastomer is caused to flow into the two runners as shown in FIG. By this method, the elastomer can be easily formed on the surface of the split housing. However, since the molten elastomer flows in the runner as described above, the elastomer that has not been used for molding remains. Since the remaining elastomer interferes with the next injection process, it is cooled and solidified in the runner by a cooling device or the like. Thereafter, the solidified elastomer is taken out from the runner and discarded, so that the melted elastomer can flow again into the runner. If the elastomer in the runner that has been solidified is heated and melted and then reused, it takes time until the elastomer melts, resulting in a problem that the newly introduced elastomer deteriorates. The solidified elastomer is taken out from the runner and discarded.
[0011]
However, in the above-described molding method, the amount of elastomer remaining / discarded is larger than the amount of elastomer used for molding, and the elastomer is expensive. Therefore, economic loss due to waste of the elastomer is large. There was a problem.
[0012]
An object of the present invention is to provide an inexpensive electric tool by solving the above-mentioned problems and reducing wasteful use of an elastomer, thereby suppressing economic loss.
[0013]
[Means for Solving the Problems]
The above object is achieved by a body trunk portion that houses the motor and the reduction mechanism unit, and a holding portion of the tool bit for transmitting rotational power from the motor, and a handle portion which are connected to the body trunk portion, and the main body portion A trigger switch provided in the vicinity of a connecting portion with a handle, and a power tool provided with a carbon brush insertion hole of the motor on a side surface of the main body body portion, both side surfaces of the main body body portion positioned above the trigger switch first and elastomer regions, and the tip tool and opposite the second elastomeric region formed from the end surface of the body trunk portion so as to cover the rear surface of the handle portion formed on said second elastomer as a region of the carbon brushes inserted around the hole from the area, until said second elastomer regions extend, a third connecting said first and second elastomeric region It has elastomer region, the first is achieved by that as the second and third elastomeric regions can be formed by injecting an elastomer from a single injection port by two-layer molding.
[0014]
DETAILED DESCRIPTION OF THE INVENTION
The electric tool in a present Example is demonstrated using FIG.1 and FIG.6. 1 is a front view showing a power tool in this embodiment, FIG. 2 is a rear view showing the power tool in this embodiment, FIG. 3 is a right side view showing the power tool in this embodiment, and FIG. 4 is in this embodiment. FIG. 5 is a partially longitudinal plan view showing a power tool in this embodiment, and FIG. 6 is a schematic side view showing a working state in which an elastomer 15 is provided on the surface of the housing 1.
[0015]
1 to 5, an impact driver or impact wrench having an outer frame such as a housing 1 and a hammer case 2 has a substantially T-shape, and a main body body portion 1b formed by the housing 1 has a drive source. The handle 3c that houses the motor 3 and the speed reduction mechanism 4 and the like, and is electrically connected to the trigger switch 5 for supplying power to the motor 2 and the connection terminal 6a of the storage battery 6 to be suspended from the body body 1b. The contact 7 to be connected is accommodated. Further, in the hammer case 2 disposed in contact with the housing 1, a striking mechanism portion 8 for converting the rotational power of the motor 2 into striking force and a tip tool holding portion 9 such as a bit or a wrench not shown are accommodated. Has been.
[0016]
In such a configuration, the rotational power of the motor 2 is transmitted from the pinion 2 a that is the output shaft of the motor 2 to the speed reduction mechanism unit 4, and the rotational force and impact are applied to the tip tool from the speed reduction mechanism unit 4 via the impact mechanism unit 8. Power is transmitted.
[0017]
The striking mechanism 8 includes a spindle 10, a hammer 12 that can be rotated through a steel ball 11 (steel ball) inserted in a cam groove 10 a formed in the spindle 10, and can move in the direction of the rotation axis. An anvil 13 having an anvil claw 13a that is struck and rotated by a plurality of hammer claws 12a, and a spring 14 that constantly biases the hammer 12 toward the anvil 13 side.
[0018]
The speed reduction mechanism unit 4 includes a fixed gear support jig 4 a, a fixed gear 4 b, a planetary gear 4 c, and a spindle 10 that are supported by a rotation stopper in the housing 1, and the planetary gear that is supported by the spindle 10. It is comprised from the needle pin 4d used as the rotating shaft of 4b.
[0019]
A pulse-like impact (impact) applied to a screw, nut, or the like that is tightened by the tip tool supplies electric power to the motor 2 by operating the trigger switch 5 and rotates the motor 2. The rotation is transmitted to the planetary gear 4b through the pinion 2a connected to the tip of the motor 2, and the rotational power of the pinion 2a is transmitted to the spindle 10 through the needle pin 4d by meshing with the planetary gear 4c and the fixed gear 4b. The rotational force of the spindle 10 is transmitted to the hammer 12 via the steel ball 11 disposed between the cam groove 10b of the tenth and the cam groove 12b of the hammer 12, and is arranged between the hammer 12 and the planetary gear 4c of the spindle 10. The hammer claw 12a of the hammer 12 urged forward (on the side of the tip tool) by the spring 14 and the anvil 1 Because the anvil claws 13a anvil 13 rotates by engaging a rotational force is applied to the tool bit. When the tightening torque of the screw or the like by the tip tool exceeds a predetermined value, the hammer pawl 13a gets over the anvil pawl 12a, so that the engagement by both claws 12a and 13a is temporarily released, that is, when the tightening torque exceeds the predetermined value. The hammer 12 moves (retreats) toward the motor 2 against the spring 14. Thereafter, the hammer 13 is pushed back in the direction of the anvil 12 by the compressive force of the spring 14, and the hammer claw 13a collides with the anvil claw 12a, thereby generating a striking force. By repeating the rotation and axial movement of the hammer in this way, continuous impact torque is applied to the tip tool. The electric power tool is provided with a rotatable hook 17 for hooking the electric tool on an operator's waist belt or the like.
[0020]
An elastomer 15 is applied to the surface of the housing 1 of the power tool having the reduction mechanism 4 described above by two-layer molding. The purpose of providing the elastomer 15 is to prevent slipping to securely hold the electric tool, or to improve gripping comfort and improve operability and workability. Further, it absorbs shock when dropped on the ground. This is to prevent the electric tool from being damaged or to prevent the electric tool from slipping along the inclination when the electric tool is placed on the inclined surface. Therefore, the elastomer 15 is mainly provided on the handle grip portion 1c of the split housing 1 and the rear surface of the main body body portion 1b.
[0021]
Also, as shown in FIG. 6, in order to mold the elastomer 15 on the surface of the split housing 1, the molten elastomer is caused to flow into one runner 16. Conventionally, when the elastomers 15 and 15a are formed at two locations on the surface of the split housing, two runners 16 'are required. However, in this embodiment, the carbon brush insertion hole is formed by one runner 16 as described above. The elastomer 15 can be formed by two-layer molding from the vicinity to the surface of the handle portion. This is because the elastomer 15, 15 a can be molded at a stretch by providing the extending portion 15 ′ (connecting portion) that connects the elastomers 15, 15 a shown in FIG. 8. Therefore, since the number of runners 16 can be reduced from two to one, the amount of the elastomer remaining in the runner 16 can inevitably be reduced. It is possible to reduce the wasteful use of expensive elastomers and to provide an inexpensive electric tool by suppressing economic loss.
[0022]
Further, by providing the extending portion 15 ′ as in this embodiment, the adhesion area of the elastomer 15 molded on the surface of the split housing 1 is increased, so that the elastomer 15 is more firmly bonded to the split housing 1. Since it can be provided on the surface and the arrangement area of the elastomer 15 on the surface of the split housing 1 is increased, the electric tool is broken along the slope when it is dropped on the ground or when the electric tool is placed on the inclined surface. It is possible to further prevent the tool from sliding off.
[0023]
【The invention's effect】
According to the present invention, by providing an extending portion formed of an elastomer in the axial direction of the motor from the carbon brush insertion hole, it is possible to reduce the wasteful use of the elastomer and to reduce the economic loss, thereby reducing the cost of the electric tool. Can be provided.
[Brief description of the drawings]
FIG. 1 is a front view showing an electric tool according to the present invention.
FIG. 2 is a rear view showing an electric tool according to the present invention.
FIG. 3 is a right side view showing an electric tool according to the present invention.
FIG. 4 is a longitudinal front view showing an electric tool according to the present invention.
FIG. 5 is a partially longitudinal plan view showing a power tool according to the present invention.
FIG. 6 is a schematic side view showing a working state in which an elastomer is provided on the surface of the housing according to the present invention.
FIG. 7 is a side view showing a split housing of a conventional electric tool.
FIG. 8 is a schematic side view showing a working state in which an elastomer is provided on the surface of a conventional housing.
[Explanation of symbols]
1 is a split housing, 1a is a mating part, 1b is a body body part, 1c is a handle part, 1d is a storage battery housing part, 2 is a motor, 2a is a pinion, 3 is a hammer case, 4 is a speed reduction mechanism part, 4a is Fixed gear support jig, 4b is a fixed gear, 4c is a planetary gear, 4d is a needle pin, 5 is a trigger switch, 6 is a storage battery, 6a is a connection terminal, 7 is a contact, 8 is a striking mechanism, and 9 is a tool holding tool 10 is a spindle, 10a is a cam groove, 11 is a steel ball, 12 is a hammer, 12a is a hammer claw, 12b is a cam groove, 13 is an anvil, 13a is an anvil claw, 14 is a spring, 15 and 15a are elastomers, 15 'Is an extending portion (connecting portion), 16 and 16' are runners, and 17 is a hook.

Claims (1)

A main body body portion that houses the motor and the speed reduction mechanism portion;
A holding part for a tip tool for transmitting rotational power from the motor;
A handle portion connected to the body trunk portion,
A trigger switch provided in the vicinity of the connecting portion between the main body body and the handle;
In the electric tool provided with a carbon brush insertion hole of the motor on the side surface of the main body body part,
A first elastomer region formed on both side surfaces of the main body body portion located on the trigger switch ;
Said tool bit opposite the second elastomer region from the end surface of the body trunk portion is formed so as to cover the rear surface of the handle portion,
As a region of the carbon brushes inserted around the hole from the second elastomer region, and extend to the second elastomer region has a third elastomer region connecting the first and second elastomer region ,
An electric tool characterized in that the first, second and third elastomer regions can be molded by injecting an elastomer from one injection port by two-layer molding.

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