JP2019022922A - Hand-held electric tool - Google Patents

Abstract

To provide a hand-held electric tool which can reduce the possibility that a cover covering a front part of a main housing falls from the main housing.SOLUTION: A hand-held electric tool includes: a housing including a main housing 11 extending in a fore and aft direction and a handle housing 12 connected to a lower part of the main housing 11 and extending downward; an output shaft protruding from a front end part of the main housing 11; and a cover 40 covering a front part of the main housing 11. The housing is formed with a recessed part 18 opening to the front side, and the cover 40 is formed with a protruding part 44 which may be inserted and fitted in the recessed part 18 from the front side. The cover 40 is fitted in the front part of the main housing 11 from the front side to cause the protruding part 44 to be inserted and fitted with the recessed part 18. In the inserted and fitted state, the protruding part 44 is fixed to the recessed part 18 by a cover fixing screw 51A to fix the cover 40 to the housing.SELECTED DRAWING: Figure 4

Description

  The present invention relates to a hand-held power tool that uses a motor as a drive source.

  Conventionally, for example, a hand-held power tool called an impact driver is known. In this type of hand-held power tool, the housing includes a cylindrical main housing extending in the front-rear direction and a handle housing extending downward from the main housing. The main housing houses a motor as a drive source and a drive transmission mechanism, and the driving force of the motor is transmitted to the output shaft through the drive transmission mechanism. The front portion of the output shaft protrudes forward from the front end portion of the main housing, and a tip tool such as a bit is detachably attached to the protruding portion.

  In such a hand-held power tool, the front part of the main housing is configured to be covered with a cover in order to prevent discomfort when the main housing whose temperature has increased during operation is gripped, to improve aesthetics, and the like. There is a case. For example, in Patent Document 1 below, the front portion of the main housing (case) is covered with a cover, the front end portion of the main housing is projected from the front end opening of the cover, and a stopper made of elastic rubber is provided on the projected front end portion. By engaging, the cover is prevented from falling off the main housing.

JP 2009-220272 A

  However, in the conventional hand-held power tool as disclosed in Patent Document 1, since the stopper is engaged with the main housing by the elastic restoring force of the elastic rubber, the engagement is accidentally released, and the stopper At the same time, the cover may fall off the main housing.

  The present invention has been made in view of the above-described problems, and an object of the present invention is to provide a hand-held power tool that can reduce the risk of the cover falling off the main housing.

  A hand-held power tool according to the present invention is housed in the main housing, including a motor as a driving source, a main housing extending in the front-rear direction, a handle housing connected to a lower portion of the main housing and extending downward. A hand-held power tool comprising a drive transmission portion, an output shaft projecting from a front end portion of the main housing, and a cover that covers the front portion of the main housing, wherein the housing has a recess opening forward. The cover is formed with a convex portion that can be inserted into the concave portion from the front, and the convex portion is inserted into the front portion of the main housing by fitting the cover from the front. The housing is inserted into the recess, and in the inserted state, the protrusion is fixed to the recess with a screw. Wherein the cover is secured.

  In the hand-held power tool according to the present invention, the recess may be formed at a connection portion of the handle housing with the main housing.

  In the hand-held power tool according to the present invention, at least a part of the housing is configured as a left / right halved structure including a right housing and a left housing, and the recess includes the right housing and the left housing. It can be set as the structure currently formed in the junction part.

  Furthermore, in the hand-held power tool according to the present invention, the screw can also function as a connecting screw that connects the right housing and the left housing.

  ADVANTAGE OF THE INVENTION According to this invention, the handheld electric tool which can reduce a possibility that a cover may drop from a main housing can be provided.

It is a left view of the hand-held power tool which concerns on one Embodiment of this invention. It is a front view of the hand-held power tool. It is BB sectional drawing in FIG. It is a principal part enlarged view of FIG. It is AA sectional drawing in FIG. It is a figure which shows the cover with which the same hand-held electric tool is provided, Comprising: (a) is the perspective view seen from the front, (b) is a left view.

  Embodiments for carrying out the present invention will be described below with reference to FIGS. In the following embodiments, a case where the present invention is applied to an impact driver that is a hand-held power tool will be described as an example. In addition, the following embodiments do not limit the invention according to each claim, and all combinations of features described in the embodiments are not necessarily essential to the solution means of the invention. .

  The impact driver 1 that is a hand-held power tool according to the present embodiment includes a housing 10 made of resin and an output shaft 21 that protrudes from a front end portion of the housing 10. A tip tool (not shown) such as a bit can be attached to the output shaft 21. The housing 10 includes a main housing 11 that extends in the front-rear direction, and a handle housing 12 that is connected to a lower portion of a middle portion of the main housing 11 in the front-rear direction and extends downward. More specifically, the output shaft 21 protrudes from the front end portion of the main housing 11. A battery pack mounting portion 19 for mounting a battery pack serving as a driving power source is provided at the lower end of the handle housing 12. In addition, although the handheld electric tool of this embodiment is a structure which includes the battery pack mounting part 19 and uses the battery pack as a power source, it is a handheld electric tool configured to include a power cord and a commercial power source. You can also

  Inside the main housing 11 are housed a motor 22 as a driving source and a drive transmission mechanism 30 for transmitting the driving force of the motor 22 to the output shaft 21. The motor 22 is housed on the rear side of the main housing 11 with the rotation axis as the front-rear direction, and the drive transmission mechanism 30 is housed on the front side of the main housing 11. The drive transmission mechanism 30 has a planetary gear mechanism 31 for decelerating the rotation of the motor 22 and an impact capable of converting the reduced rotational output of the motor 22 into an impact force in the rotational direction and transmitting it to the output shaft 21. And a mechanism 32. Since the drive transmission mechanism 30 is conventionally known, detailed description thereof is omitted.

  On the upper front side of the handle housing 12, a trigger switch 23 for operating the impact driver 1 is disposed so as to protrude forward. The trigger switch 23 is configured to be able to be withdrawn from and retracted from the handle housing 12 so that the impact driver 1 starts to be operated by being pushed inward by a finger of a hand holding the handle housing 12. It is configured. Above the trigger switch 23 of the handle housing 12 is a connecting portion 13 that is connected to the lower portion of the middle portion of the main housing 11 in the front-rear direction. A forward / reverse switching lever 14 for switching the rotation direction of the output shaft 21 between the forward rotation direction and the reverse rotation direction is disposed at the center portion in the front-rear direction of the connection portion 13 so as to protrude outward from the left and right side surfaces of the connection portion 13. Has been. An illumination tool 15 for irradiating the front is installed inside the front end portion of the connection portion 13. Note that the front end of the connecting portion 13 is located behind the front end of the main housing 11.

  The front part of the main housing 11 is formed such that the outer surface is reduced in diameter toward the front end part, and is covered with a cover 40 fitted from the front. The cover 40 is made of resin and has a cylindrical portion 41 formed to have an inner surface shape along the outer shape of the front outer surface of the main housing 11 and a circular front end formed at the front end of the cylindrical portion 41. An opening 42, a circular rear end opening 43 formed at the rear end of the cylindrical portion 41, and a convex portion 44 protruding rearward and downward from the lower rear end of the cylindrical portion 41 are integrally formed. Has been. The convex portion 44 is formed in a rectangular shape that is long in the front-rear direction in a side view in the left-right direction, and a circular through hole 45 penetrating in the left-right direction is formed near the rear portion. Further, the convex portion 44 is formed in a rectangular shape that is long in the vertical direction in a cross-sectional view in the front-rear direction. When the cover 40 is fitted on the front portion of the main housing 11, the front end surface of the front end opening 42 substantially coincides with the front end surface of the main housing 11 and the front end surface of the convex portion 44 is connected. The front end surface of the portion 13 and the position in the front-rear direction substantially coincide. The rear end surface of the rear end opening 43 is opposed to the enlarged diameter step surface 16 of the main housing 11.

  The connecting portion 13 of the handle housing 12 is formed with a recess 18 having an insertion opening 18c that opens toward the front and extending rearward. The recess 18 is located on the upper side of the lighting tool 15 and immediately below the main housing 11. The recess 18 communicates with the internal space of the housing 10. The concave portion 18 is formed so that the convex portion 44 is inserted when the cover 40 is fitted to the front portion of the main housing 11 from the front. The cover fixing screw 51A penetrating the concave portion 18 in the left-right direction is inserted into the concave portion 18 and the through hole 45 of the convex portion 44 is inserted and tightened, so that the convex portion 44 becomes the concave portion. 18 is fixed. Specifically, the convex portion 44 is sandwiched between the left and right inner walls of the concave portion 18 by tightening the cover fixing screw 51A, and the cover fixing screw 51A is inserted through the through hole 45, so that the cover fixing screw 51A The cover 40 is configured and fixed so that the cover 40 does not come off the housing 10 even when the clamping is loosened and the clamping force is reduced. This cover fixing screw 51A corresponds to the screw of the present invention.

  As will be described later, the cover fixing screw 51A also has a function as a connecting screw for connecting the housings.

  In the present embodiment, the housing 10 is configured as a left / right halved structure including a right housing 10a and a left housing 10b. That is, the right housing 10a has a right main housing 11a and a right handle housing 12a, and the left housing 10b has a left main housing 11b and a left handle housing 12b. The right housing 10a and the left housing 10b are formed so that the central portion in the left-right direction becomes the joint portion 10c. In a part of the joint portion 10c, concave-convex joining is employed in order to prevent the internal lubricant from leaking to the outside and preventing water or the like from entering the inside from the outside. The right housing 10a and the left housing 10b are connected by a plurality of connecting screws 51 whose axis is in the left-right direction. Specifically, the right housing 10a and the left housing 10b are connected by inserting a plurality of connecting screws 51 into the holes 10d formed in the right housing 10a from the right side and screwing them into the screw holes 10e of the left housing 10b. Is done. One of the plurality of connecting screws 51 also serves as the cover fixing screw 51A described above. In the present embodiment, the entire housing 10 has a left / right halved structure, but the front side of the main housing 11 may be configured separately from a metal or the like as a cylindrical housing having no left / right halved structure.

  A recess 18 formed in the connection portion 13 of the handle housing 12 is formed in a joint portion 10c between the right housing 10a and the left housing 10b. Accordingly, the recess 18 is located at the center in the left-right direction of the housing 10. Specifically, the recess 18 is formed at a joint 10c between the right handle housing 12a and the left handle housing 12b. The right handle housing 12a forms a right inner wall 18a of the recess 18, and the left handle housing 12b sets the recess. 18 left inner walls 18b are formed. That is, the right inner wall 18a and the left inner wall 18b correspond to the left and right inner walls that sandwich the convex portion 44 described above.

  In the present embodiment, two seal rings 61 are provided between the inner surface of the cover 40 and the outer surface of the main housing 11. The seal ring 61 is disposed so as to be held in a circumferential groove formed on the outer surface of the main housing 11 on both front and rear sides of the connecting screws 51B and 51C located on the foremost side. This is to cope with grease leakage that may occur when the joint 10c around the connection screws 51B and 51C is deformed by the tightening of the connection screws 51B and 51C and a gap is generated. That is, even when the grease that is the lubricant applied to the drive transmission mechanism 30 leaks from the generated gap between the outer surface of the main housing 11 and the inner surface of the cover 40, the leaked grease is removed from the two seal rings 61. It is configured so that it can be kept between. Therefore, it is possible to prevent the grease from leaking to the outer surface of the impact driver 1.

  As described above, in the impact driver 1 that is a hand-held power tool according to the present embodiment, the convex portion 44 formed on the cover 40 is inserted into the concave portion 18 formed on the housing 10, and the convex portion 44 is inserted into the convex state. By fixing the portion 44 to the concave portion 18 with the cover fixing screw 51 </ b> A, the cover 40 can be securely fixed to the housing 10. Therefore, the possibility that the cover 40 may fall off the housing 10 can be reduced.

  In addition, since the concave portion 18 is formed in the connection portion 13 of the handle housing 12, the front end portion of the main housing 11 protrudes forward from the cover, and compared with the configuration that prevents the cover from falling off using this protruding portion, The overall length can be shortened. Therefore, the apparatus can be made compact.

  Further, since the concave portion 18 is formed in the connection portion 13 of the handle housing 12, a clean appearance can be easily obtained as compared with the case where the concave portion is formed on the left and right side portions or the upper portion of the main housing 11.

  Furthermore, since the housing 10 has a left / right halved structure including the right housing 10a and the left housing 10b, and the concave portion 18 is formed in the joint 10c between the right housing 10a and the left housing 10b, a resin molding die for manufacturing the housing is provided. Can be complicated. Therefore, it can be manufactured inexpensively.

  Further, since the connecting screw 51 for connecting the right housing 10a and the left housing 10b is also used as the cover fixing screw 51A for fixing the cover, the number of parts can be reduced and the assembly workability can be prevented from being lowered. it can.

  As mentioned above, although embodiment of this invention was described, the technical scope of this invention is not limited to the range as described in the said embodiment. Various modifications or improvements can be added to the embodiment.

  For example, in the above-described embodiment, the hand-held power tool is configured as an impact driver, but is not limited thereto. For example, it can also be configured as a drill.

  For example, in the above-described embodiment, the cover 40 is made of resin, but is not limited thereto. For example, you may manufacture with rubber | gum with comparatively high hardness. Or the cover of the structure which covered the outer surface of the cover main body which consists of resin with soft materials, such as an elastomer, may be sufficient. In addition, when it manufactures with rubber | gum, or the structure covered with the soft material, the damage | wound generation | occurrence | production to the other member by contact can be prevented.

  Further, for example, in the above-described embodiment, the motor 22 is accommodated on the rear side of the main housing 11 with the rotation axis as the front-rear direction, but is not limited thereto. For example, a motor housing area may be formed in the handle housing, and the motor may be housed in the motor housing area with the rotation axis as the vertical direction. In this case, the motor and the drive transmission mechanism are connected by a connecting portion having a bevel gear or the like.

1: impact driver 10: housing 10a: right housing 10b: left housing 10c: joint 10d: hole 10e: screw hole 11: main housing 11a: right main housing 11b: left main housing 12: handle housing 12a: right handle housing 12b : Left handle housing 13: Connection portion 14: Forward / reverse switching lever 15: Illuminator 16: Expanded step surface 18: Recessed portion 18a: Right inner wall 18b: Left inner wall 18c: Insertion opening 19: Battery pack mounting portion 21: Output shaft 22 : Motor 23: Trigger switch 30: Drive transmission mechanism 31: Planetary gear mechanism 32: Impact mechanism 40: Cover 41: Cylindrical part 42: Front end opening 43: Rear end opening 44: Convex part 45: Through hole 51: Connection screw 51A : Cover fixing screw 51B: Connection screw 51C: Connection Di 61: seal ring

Claims (4)

A motor as a drive source;
A housing comprising a main housing extending in the front-rear direction and a handle housing connected to a lower portion of the main housing and extending downward;
A drive transmission unit housed in the main housing;
An output shaft protruding from the front end of the main housing;
In a hand-held power tool comprising a cover that covers the front portion of the main housing,
The housing is formed with a concave portion that opens forward, and the cover is formed with a convex portion that can be inserted into the concave portion from the front.
By fitting the cover on the front part of the main housing from the front, the convex part is inserted into the concave part,
In the inserted state, the cover is fixed to the housing by fixing the convex portion to the concave portion with a screw.   The hand-held power tool according to claim 1, wherein the recess is formed in a connection portion of the handle housing with the main housing. At least a part of the housing is configured as a left / right halved structure including a right housing and a left housing,
The hand-held power tool according to claim 1 or 2, wherein the recess is formed at a joint between the right housing and the left housing.   The hand-held power tool according to claim 3, wherein the screw also functions as a connection screw that connects the right housing and the left housing.

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