阅读说明：本技术 一种手持式电动工具多位开关 (Hand-held electric tool multi-position switch ) 是由 张成龙 于 2021-09-02 设计创作，主要内容包括：本发明涉及一种手持式电动工具多位开关,属于电动工具技术领域。该开关包括一个安置于壳体的开关件和一个位于开关件上的扳机,开关件具有松释和按压位置,扳机可分别以两端为支点摆转；壳体上还间隔铰支有位于扳机下的前翘板和后翘板；当扳机的后部受压绕前支点摆转时,扳机的后部直接通过后翘板的后部下压开关件；当扳机的前部受压绕后支点摆转时,扳机的前部通过前翘板使后翘板的后部下压开关件；当扳机的中部受压时,扳机的前部和后部分别作用于前翘板和后翘板,使后翘板的后部下压开关件。采用本发明后,无论在何处按压扳机,均可以轻松省力实现开关件完成所需操控。(The invention relates to a multi-position switch of a hand-held electric tool, belonging to the technical field of electric tools. The switch comprises a switch piece arranged on the shell and a trigger positioned on the switch piece, wherein the switch piece is provided with releasing and pressing positions, and the trigger can swing and rotate by taking two ends as pivots respectively; the shell is also hinged with a front rocker and a rear rocker which are positioned under the trigger at intervals; when the rear part of the trigger is pressed to swing around the front pivot, the rear part of the trigger directly presses the switch piece through the rear part of the rear rocker; when the front part of the trigger is pressed to swing around the rear point, the rear part of the rear rocker presses the switch piece downwards through the front rocker by the front part of the trigger; when the middle portion of the trigger is pressed, the front portion and the rear portion of the trigger act on the front rocker and the rear rocker, respectively, so that the rear portion of the rear rocker presses the switch member. After the invention is adopted, the switch part can be easily operated and controlled in a labor-saving way no matter where the trigger is pressed.)

1. A hand-held type electric tool multiposition switch is characterized in that: the switch comprises a switch piece arranged on a shell and a trigger positioned on the switch piece, wherein the switch piece is provided with releasing and pressing positions, and the trigger can swing around two ends as pivots respectively;

the shell is also hinged with a front rocker and a rear rocker which are positioned below the trigger at intervals, the rear end of the front rocker is positioned below the front end of the rear rocker, and the rear part of the rear rocker is positioned above the switch piece;

when the rear part of the trigger is pressed to swing around the front pivot, the rear part of the trigger directly presses the switch piece downwards through the rear part of the rear rocker;

when the front part of the trigger is pressed to swing around a rear point, the rear part of the rear rocker is pressed down to the switch piece through the front rocker by the front part of the trigger;

when the middle part of the trigger is pressed, the front part and the rear part of the trigger respectively act on the front rocker and the rear rocker, so that the rear part of the rear rocker presses the switch piece.

2. The hand held power tool multi-position switch of claim 1, wherein: the front supporting point and the rear supporting point are respectively constrained in a front sliding groove and a rear sliding groove at corresponding positions of the shell.

3. The hand held power tool multi-position switch of claim 2, wherein: a front lower projection and a rear lower projection extend from the inner surface of the trigger and correspond to the front portion of the front rocker and the rear portion of the rear rocker, respectively.

4. The hand held power tool multi-position switch of claim 3, wherein: the rear part of the rear rocker is provided with a front upper concave corresponding to the rear lower convex.

5. The hand held power tool multi-position switch of claim 4, wherein: the rear portion of the rear rocker has a rear recess corresponding to the switch member.

6. The hand held power tool multi-position switch of claim 5, wherein: the deepest parts of the front upper concave and the rear lower concave are positioned on the same straight line with the center of the hinge pin of the rear rocker.

7. The hand held power tool multi-position switch of claim 6, wherein: the lower part of the rear end of the front rocker abuts against the upper end of a spring of which the lower end is constrained on the limiting stop of the shell.

Technical Field

The invention relates to a press control switch, in particular to a multi-position switch of a handheld electric tool, and belongs to the technical field of electric tools.

Background

The holding part of the hand-held electric tool such as an angular impact screwdriver, an angular impact wrench and the like is provided with a press type control switch. In order to facilitate different manipulations for various applications, the grip portion and the trigger controlling the switch are usually of a certain length. US patent application No. US8853578B discloses a power tool comprising: a housing; an elongated paddle member (i.e., trigger) having a first end and a second end, the first end being movable toward and away from the housing and the second end being movable toward and away from the housing; a support surface disposed on the paddle member; a switch mechanism having a first position and a second position; a pivot member coupled to the housing and positioned a distance from the support surface such that application of a force on the input surface changes the distance between the pivot member and the support surface; a multiplying element coupled to the pivot element and including a first arm, the multiplying element configured to contact the support surface such that application of a force at the input surface causes angular displacement of the multiplying element about the pivot member, the angular displacement of the multiplying element causing the first arm to move the switching mechanism from the first position to the second position when the application of the force is proximate the first end of the slurry element, and the multiplying element further causing the first arm to move the switching mechanism from the first position to the second position when the application of the force is proximate the second end of the slurry element. After the technical scheme of the patent is adopted, no matter the front part, the middle part or the rear part of the holding part is held by hands during operation, the trigger of the control switch can be pressed to realize the required control, so that certain convenience is brought to the control.

However, when the multifunctional electric wrench is used, the front part or the rear part of the wrench of the control switch is pressed to feel easy and labor-saving, and the middle part of the wrench is pressed to feel obvious labor-saving, so that the hand feeling of control is poor, and the middle part of the wrench is held to control the wrench easily and fatiguedly.

Disclosure of Invention

The invention aims to: aiming at the problems in the prior art, the multi-position switch of the handheld electric tool is provided, and the switch trigger can be easily and labor-saving when pressed anywhere.

In order to achieve the above object, the applicant has conducted an in-depth analysis of the above prior art:

as shown in fig. 1, when a pressing force F is applied to a point a at one end, the trigger rotates around a point C, the stroke of a point E of the switch is L, and the switch needs to move down by a distance L (AC BD/BC ED) to a point a at the bottom; if alpha is an included angle between BD and ED and beta is an included angle between DB and CB, the stress Fb = F (AC/BC) at the point B; switch point E is forced by Fe = F COS α COS β (AC BD/BC ED).

As shown in fig. 2, when a pressing force F is applied to the other end point C, the trigger rotates around point a, the stroke of point E of the switch is L, and the switch needs to be moved down by a distance L (AC BD/AB ED) to the point C; if alpha is an included angle between BD and ED, beta' is an included angle between DB and AB, and gamma is an included angle between CA and BA, the stress Fb = F × COS γ (AC/AB) at the point B; the switch point E is stressed with Fe = F COS α COS β'. COS γ (AC BD/AB ED).

As shown in fig. 3, when a pressing force F is applied in the middle of the trigger, the trigger does not rotate around points a and C, but both ends are simultaneously displaced downward; the travel of the switch E point is L, if the switch E point is pressed to the bottom, the point B needs to move downwards by a distance of L (BD/ED); point B force Fb = F; switch point E is forced by Fe = F COS α (BD/ED).

From the analysis, when the pressing force is applied to the two ends A or C to actuate the switch, only about half of the acting force is needed to be applied to the middle to actuate the switch, so the frame in the prior art needs to be broken through to achieve the purpose of the invention.

On the basis of the analysis, the basic technical scheme of the multi-position switch of the handheld electric tool of the applicant is as follows: the switch comprises a switch piece arranged on a shell and a trigger positioned on the switch piece, wherein the switch piece is provided with releasing and pressing positions, and the trigger can swing around two ends as pivots respectively;

the shell is also hinged with a front rocker and a rear rocker which are positioned below the trigger at intervals, the rear end of the front rocker is positioned below the front end of the rear rocker, and the rear part of the rear rocker is positioned above the switch piece;

when the rear part of the trigger is pressed to swing around the front pivot, the rear part of the trigger directly presses the switch piece downwards through the rear part of the rear rocker;

when the front part of the trigger is pressed to swing around a rear point, the rear part of the rear rocker is pressed down to the switch piece through the front rocker by the front part of the trigger;

when the middle part of the trigger is pressed, the front part and the rear part of the trigger respectively act on the front rocker and the rear rocker, so that the rear part of the rear rocker presses the switch piece.

Theoretical analysis and experiments show that after the technical scheme of the invention is adopted, when the front end and the rear end of the trigger are respectively applied with pressing force, the acting force required by the switch action is equivalent to that of the prior art, and when the middle of the trigger is applied with the pressing force to make the switch act, the acting force is reduced by about half compared with that of the prior art, so that the switch piece can be easily operated and controlled in a labor-saving manner no matter where the trigger is pressed. Therefore, the invention breaks through the frame in the prior art, and achieves the purpose of the invention through the combined lever mechanism formed by the front and rear seesaws.

Drawings

The invention will be further described with reference to the accompanying drawings.

Fig. 1 is a schematic diagram of a force analysis of a state one of a push switch in the prior art.

Fig. 2 is a schematic diagram of force analysis of a state two of a push switch in the prior art.

Fig. 3 is a schematic diagram of force analysis of state three of the prior art push switch.

FIG. 4 is a perspective view of an angular impact screwdriver according to one embodiment of the present invention.

Fig. 5 is a schematic structural view of the non-stressed state in the pressed state of fig. 4.

FIG. 6 is a schematic diagram of the rear end of the push trigger of FIG. 4 in a stressed state.

FIG. 7 is a schematic view of the front end of the pressing trigger shown in FIG. 4 in a stressed state.

Fig. 8 is a structural schematic diagram of a stressed state of the middle part of the pressing trigger in fig. 4.

Detailed Description

Example one

The hand-held electric tool multi-position switch of the embodiment is applied to an angular impact screwdriver shown in fig. 4, a shell as a holding part is formed by oppositely combining a left shell 4 and a right shell 3, a motor 6 and a pressing type switch piece 5 are arranged in the shell, and a transmission head 1 is arranged at the front end of the shell by means of a screw 2 and used for driving the screwdriver head matched during operation.

As shown in fig. 5, the switch 5 with two positions of releasing power and pressing power is provided with a front support point 11.1 and a rear support point 11.4 which are respectively constrained in the front chute 3.1 and the rear chute 3.3 of the corresponding position of the shell, and the trigger 11 can respectively swing by taking two ends as pivots. The housing is also pivotally mounted at intervals by two pivot pins 8 to a front rocker 10 and a rear rocker 9 which are located below the trigger 11.

The trigger 11 internal surface extends and corresponds preceding lower arch 11.2 and the lower arch 11.3 in back respectively in front of preceding wane 10 and back wane 9 rear portion, and the rear portion of back wane 9 is located the top of switch 5, has preceding upper concavity and the back is sunken corresponding to back lower arch 11.3 and switch 5 respectively to preceding upper concavity and the deepest of back is in same straight line S with the hinge pin 8 center of back wane 9, so not only can make back wane 9 stress condition good, and the motion links up steadily. The rear end of preceding wane 10 is located the below of back wane 9 front end, and the rear end lower part of preceding wane 10 supports and leans on in the lower extreme restraint spring 7 upper end at the spacing fender 3.2 of casing, consequently has the trend of leaning on back wane 9 front end all the time, can avoid appearing loose phenomenon in its working process.

When the angular impact screwdriver of the embodiment is held at the rear part of the shell to operate the trigger, as shown in fig. 6, the rear part of the trigger 11 is pressed by a pressure F, a front supporting point 11.1 of the rear part of the trigger 11 becomes a swinging supporting point of the trigger 11 after rising to an upper extreme position along a front sliding groove 3.1 of the shell, and the rear part of the trigger 11 directly presses down a front upper concave part at the rear part of the rear rocker 9 through a rear lower convex 11.3 and then presses down the switch piece 5 through a rear lower concave part at the rear part of the rear rocker 9, so that the required operation is realized.

When the trigger is operated by holding the front part of the housing, as shown in fig. 7, the front part of the trigger 11 is pressed by a pressure F, and the rear fulcrum 11.4 rises to an upper limit position along the rear chute 3.3 of the housing to become a swing fulcrum of the trigger 11, the front part of the trigger 11 presses down the front part of the front rocker 10 through the front lower bulge 11.2, and then the front end of the rear rocker 9 is tilted up by the rear end of the front rocker 10, so that the rear lower concave lower part at the rear part of the rear rocker 9 presses the switch 5, and the required operation is realized.

When the trigger is operated by holding the trigger in the middle of the shell, as shown in fig. 8, the middle part of the trigger 11 is pressed by a pressure F, and the front and rear points 11.1 and 11.4 of the trigger descend along the front and rear sliding grooves 3.1 and 3.3 of the shell respectively, so that the front lower bulge 11.2 and the rear lower bulge 11.3 of the trigger 11 act on the front part of the front rocker 10 and the rear part of the rear rocker 9 respectively, and the rear concave lower part at the rear part of the rear rocker 9 presses the switch piece 5 to realize the required operation.

The mechanical analysis of each working state in this embodiment is as follows:

in the state of fig. 6, point M presses against force F and the rear rocker rotates about point P. The switch stroke is L, the switch is required to be moved down by a distance L (PM/PN) when the switch is pressed to the point M, and the force Fn = F (PM/PN) is applied to the point N of the switch. Comparing the analysis of fig. 1, it can be seen that the stress at point M is slightly less than the stress at the corresponding location in the prior art.

In the state of fig. 7, the point T presses the pressure F, the front rocker rotates around the point Q, the rear rocker is driven to rotate around the point P, and the front rocker and the rear rocker contact S. The switch travel is L, and the switch is moved down by a distance L (TQ SP/SQ NP) to the point T, and the force Fn = F (TQ SP/SQ NP) is applied to the point N. Comparing the analysis of fig. 2, it can be seen that the stress at point T is slightly smaller than that at the corresponding position in the prior art.

In the state of fig. 8, the trigger intermediate pressing force F, the front rocker and the rear rocker simultaneously generate component forces F1 and F2, F1+ F2= F. The switch stroke is L, the switch is pressed to the bottom point M by the distance L (PM/PN), the point T is moved by the distance L (TQ SP/SQ NP), the trigger middle position downward movement distance is 1/2 (L (TQ SP/SQ NP) + L (PM/PN)), and the switch point stress Fn = F1 (TQ SP/SQ NP) + F2 (PM/PN). Comparing the analysis of fig. 3, it can be seen that the force applied to the middle pressing force F is reduced by about half compared with the force applied to the corresponding position in the prior art, and the stability is better because the two positions of the trigger are respectively in contact with the front and rear rocker to apply force.

The conditions of the comparative tests are shown in the following table:

therefore, theoretical analysis and experiments show that after the technical scheme of the embodiment is adopted, the trigger can be controlled more easily, particularly, the middle control acting force is obviously reduced to be equivalent to that of the two ends, so that the electric tool has good control feeling and is more comfortable to use.

In addition to the above embodiments, the present invention may have other embodiments. All technical solutions formed by adopting equivalent substitutions or equivalent transformations fall within the protection scope of the claims of the present invention.