JP2014133284A - Switch mechanism of power tool - Google Patents

Abstract

PROBLEM TO BE SOLVED: To reduce labor and manufacturing cost of management, even if an automatic recovery type and an automatic non-recovery type of a lock-off member are manufactured.SOLUTION: A switch mechanism such as a reciprocation saw can be respectively selectively attached with, on the pushing-in side of a switch lever in a housing 2, a first lock-off button 20 movable to a lock-off releasing position for allowing ON of a switch caused by pushing-in of the switch lever from a lock-off position for maintaining an OFF state of the switch with operation from outside of the housing 2 and automatically recoverable to the lock-off position by a release of the operation from outside of the housing 2 and a second lock-off button 30 movable to the lock-off position and the lock-off release position with the operation from outside of the housing 2.

Description

  The present invention relates to a switch mechanism for a power tool such as an electric tool or an air tool, in which a housing is provided with a switch for operating a prime mover and an operation member that can be pushed into the switch.

  In a power tool such as an electric tool or an air tool, a switch for driving a motor such as a motor is turned on by pushing an operation member such as a trigger. However, a device using a safety device (lock-off mechanism) is known to prevent the switch from being turned ON accidentally. For example, Patent Document 1 discloses an engagement member (lock-off member) that is normally biased to a lock-off position that prevents the operation member from being pushed in, and a push button that retracts the engagement member from the lock-off position by a push-in operation. A lock-off mechanism provided with is disclosed. Here, when the push button is released, the engaging member automatically returns to the lock-off position. Further, in the cited document 2, an operation element (lock-off member) provided with an abutting portion that engages with the convex portion of the operation member and a notch portion through which the convex portion passes can be rotated in the vicinity of the trigger. There is disclosed a lock-off mechanism that allows selection of a lock-off position for locking a trigger and a lock-off release position for releasing the lock by rotating the operating element.

Japanese Utility Model Publication No. 56-1336 Japanese Utility Model Publication No. 6-31965

  The lock-off mechanism in which the lock-off member automatically returns to the lock-off position and the lock-off mechanism that selectively switches between the lock-off position and the lock-off release position are different from each other in the constituent members. The form of the housing to be used is also different. Therefore, when manufacturing a type that automatically returns and a type that does not automatically return even with the same power tool, it is necessary to manufacture a housing for each type, which requires management effort and manufacturing cost.

  Therefore, the present invention has an object to provide a power tool switch mechanism that can reduce the labor and cost of management even when a type in which a lock-off member is automatically restored and a type in which a lock-off member is not automatically restored are manufactured. Is.

In order to achieve the above object, the invention according to claim 1 is a switch mechanism of a power tool provided with a switch for operating a prime mover and an operation member which can be pushed into the switch side in a housing, The housing can be moved from a lock-off position that maintains the switch OFF state by an operation from outside the housing to a lock-off release position that allows the switch to be turned on when the operation member is pushed in, and the operation from the outside of the housing is released. The first lock-off member that can be automatically returned to the lock-off position by the operation and the second lock-off member that can be moved to the lock-off position and the lock-off release position by an operation from the outside of the housing. It is characterized in that it can be assembled.
According to a second aspect of the present invention, in the configuration of the first aspect, an elastic body is used for the automatic return of the first lock-off member.
According to a third aspect of the present invention, in the configuration of the second aspect, the second lock-off member is engaged with an engagement member provided in the housing at the lock-off position and the lock-off release position. Is.
According to a fourth aspect of the present invention, in the configuration according to any one of the first to third aspects, the first lock-off member interferes with the operation member in the lock-off position to prevent the pushing operation of the switch. An OFF state is maintained.
According to a fifth aspect of the present invention, in the configuration of the third aspect, the elastic body and the engaging member can be assembled at the same position of the housing.

According to the first aspect of the present invention, the type in which the lock-off member automatically returns to the lock-off position and the type in which the lock-off member does not automatically return can be selectively assembled by a common housing. Therefore, it is possible to expect a reduction in management effort and manufacturing costs.
According to the second aspect of the invention, in addition to the effect of the first aspect, the first lock-off member can be easily automatically restored by adopting the elastic body.
According to the third aspect of the present invention, in addition to the effect of the second aspect, the engagement member can be used to reliably switch between the lock-off position and the lock-off release position.
According to the invention described in claim 4, in addition to the effect of any one of claims 1 to 3, the lock-off by the first lock-off member can be reliably performed.
According to the fifth aspect of the invention, in addition to the effect of the third aspect, the common use of the housing can be maintained even if an elastic body and an engaging member are used in addition to the lock-off button, which leads to a reduction in manufacturing cost. .

It is explanatory drawing of a reciprocating saw (equipped with the lock-off mechanism which resets automatically). It is a disassembled perspective view of a housing and a 1st, 2nd lock-off button. FIGS. 2A and 2B are cross-sectional views taken along line A-A in FIG. 1, and FIGS. FIGS. 2A and 2B are cross-sectional views taken along the line BB in FIG. 1, and FIGS. It is explanatory drawing of a reciprocating saw (equipped with the lock-off mechanism which does not reset automatically). FIGS. 5A and 5B are cross-sectional views taken along the line C-C in FIG. 5. FIG. 5A shows a lock-off position, and FIG. 6A and 6B are cross-sectional views taken along the line D-D in FIG. 5, where FIG. 5A shows a lock-off position, and FIG.

Hereinafter, embodiments of the present invention will be described with reference to the drawings.
FIG. 1 is an explanatory view showing a rechargeable reciprocating saw (hereinafter simply referred to as “reciprocating saw”) as an example of a power tool. The reciprocating saw 1 is an abbreviation of a housing 2 formed by assembling halved left and right housings 3 and 4. A motor 5 is accommodated in the center, and a battery pack 6 serving as a power source is attached to the rear end of the housing 2 (the right side in FIG. 1 is the front). A slider 7 that reciprocates via a conversion mechanism as the motor 5 rotates is provided at the front end of the housing 2, and a blade (not shown) can be attached to the tip of the slider 7.

  A switch 8 is mounted on the rear side of the motor 5 and includes a plunger 9 that is projected and biased toward an opening 10 formed on the lower surface of the housing 2. In addition, a switch lever 11 as an operation member is provided in the opening 10 so as to be rotatable about a horizontal axis 12 provided at the rear end. The switch lever 11 is urged to the protruding position from the opening 10 by the plunger 9, and the switch 8 can be turned on by pushing the plunger 9 by the pushing operation into the housing 2. A pair of left and right protrusions 13 are formed on the outer surface of the front end of the switch lever 11 along the rotation direction of the switch lever 11 around the shaft 12.

  Furthermore, on the inner surfaces of the left and right housings 3 and 4 inside the switch lever 11, receiving seats that can be assembled by selecting either a first lock-off button 20 or a second lock-off button 30 described later are provided. ing. FIG. 2 shows a receiving seat 14 provided in the left housing 3. The receiving seat 14 has a cylindrical rib 16 standing around a through hole 15 formed in the left housing 3, and a switch lever 11 that is continuous with the cylindrical rib 16 and partitions the motor 5 and the switch 8. Wall ribs 17 standing up to the vicinity of the front end. A boss 18a having a circular cross section toward the right housing 4 is formed at the end of the wall rib 17 on the switch lever 11 side. The cylindrical rib 16 and the wall rib 17 are also provided on the inner surface of the right housing 4 so as to face each other. However, the wall rib 17 and the boss 18b (FIG. 4) are lower on the right housing 4 side. Yes.

  The first lock-off button 20 assembled to the receiving seat 14 is a shaft body having a circular cross section, and a chamfered portion 21 is formed at a central portion, and the chamfered portion 21 projects in a tangential direction. A plate-like arm portion 22 is formed. A pair of ridges 23, 23 extending in the radial direction protrude from the inner surface of the arm portion 22, and a holding portion 24 having a U-shape in a side view is connected to the outer surface. A coil spring 25 as an elastic body is held in the holding portion 24 in a state of being prevented from coming off in the axial direction. The coil spring 25 is positioned coaxially with the bosses 18 a and 18 b at the position where the first lock-off button 20 is inserted into the cylindrical rib 16 of the receiving seat 14.

On the other hand, the second lock-off button 30, like the first lock-off button 20, is a shaft having a circular cross section, and a chamfered portion 31 is formed in the center portion. A plate-like arm portion 32 protruding in the tangential direction is formed. A pair of protrusions 33, 33 extending in the radial direction are formed on the inner surface of the arm portion 32, and a pair of locking grooves 34, 34 extending in the radial direction are formed on the outer surface.
Further, here, the engaging tool 35 as an engaging member is used together. This engagement tool 35 is a plate-like elastic body (for example, a sheet metal) bent in a U-shape, and a base 36 is formed with a through hole 36 through which the boss 18a on the left housing 3 side can pass. It can be assembled in a state of straddling the end portion of the wall rib 17 on the left housing 3 side in a state of passing through the through hole 36. In this assembled state, one end portion 37 of the engagement tool 35 is positioned along the arm portion 32 of the second lock-off button 30. The end portion 37 is formed with a protrusion 38 that can be locked in locking grooves 34, 34 provided in the arm portion 32.

  In the switch mechanism of the reciprocating saw 1 configured as described above, the lock-off button is locked off by selecting either the first lock-off button 20 or the second lock-off button 30 and assembling it in the common housing 2. A lock-off mechanism that automatically returns to the position and a lock-off mechanism that does not automatically return can be selected. Hereinafter, this selection will be described in detail.

  First, when selecting a lock-off mechanism that automatically returns, as shown in FIGS. 1 and 2, a coil spring 25 in which the first lock-off button 20 is held by the holding portion 24 with the left housing 3 in the down position. One end is inserted into the cylindrical rib 16 of the seat 14 in the direction in which the boss 18a is inserted. When the right housing 4 is assembled, the other end is inserted into the cylindrical rib 16 of the receiving seat 14 on the right housing 4 side, and the bosses 18a and 18b abut against each other, so that the coil spring 25 is located at an intermediate position between the left and right housings 3 and 4. Held in. Therefore, the first lock-off button 20 is also held at an intermediate position between the left and right housings 3 and 4 whose both ends protrude from the through holes 15 as shown in FIGS. 3 (B) and 4 (B).

  In this intermediate position, since the protrusions 23 and 23 provided on the arm portion 22 of the first lock-off button 20 are located in front of the protrusions 13 and 13 in the pushing direction of the switch lever 11, the switch lever 11 is Even if it tries to push in, pushing of the switch lever 11 is prevented by the interference between the protrusion 13 and the protrusion 23. That is, the intermediate position is the lock-off position.

When the left end portion of the first lock-off button 20 is pushed from this lock-off position and is slid to the right side, as shown in FIGS. 3 (A) and 4 (A), the ridge 23 of the first lock-off button 20 is obtained. , 23 slides to the right and retracts from the front of the protrusions 13, 13 (front of the switch lever 11 in the pushing direction), so that the switch lever 11 can be pushed in (lock-off release position). Therefore, the plunger 9 is pushed in, the switch 8 is turned on, the motor 5 is driven, and the slider 7 reciprocates.
When the first lock-off button 20 is pushed in, the coil spring 25 is compressed between the tip of the boss 18b of the right housing 4 and the end of the holding part 24, so that the push-in of the first lock-off button 20 is released. Then, the first lock-off button 20 is automatically returned to the lock-off position by the bias of the coil spring 25.

On the other hand, when the right end portion of the first lock-off button 20 is pushed in from the lock-off position and is slid to the left side, as shown in FIGS. 3C and 4C, the protrusion of the first lock-off button 20 is formed. Since 23 and 23 slide to the left and retract from the front of the protrusions 13 and 13, the switch lever 11 can be pushed in (lock-off release position).
Also in this case, the coil spring 25 is compressed between the base portion of the boss 18a of the left housing 3 and the end portion of the holding portion 24 when the first lock-off button 20 is pushed in. If the pushing is released, the first lock-off button 20 is automatically returned to the lock-off position by the bias of the coil spring 25.

  When selecting a lock-off mechanism that does not automatically return, as shown in FIGS. 2 and 5, the holder 35 is first passed through the tip of the boss 18 a through the through hole 36 with the left housing 3 facing down. Then, the end portion 37 having the projection 38 is set on the receiving seat 14 at a position facing the cylindrical rib 16 side. Next, one end of the second lock-off button 30 is inserted into the cylindrical rib 16 of the receiving seat 14 of the left housing 3 with the arm 32 extending along the end 37 of the holder 35. When the right housing 4 is assembled, the other end is inserted into the cylindrical rib 16 of the seat 14 on the right housing 4 side. Therefore, the second lock-off button 30 is slidably held between the left and right housings 3 and 4, but the end portion 37 of the engagement tool 35 is attached to the arm portion 32 of the second lock-off button 30 in the assembled state. Is elastically pressed, the slide of the second lock-off button is elastically restricted at the slide position where the projection 38 is locked in either of the locking grooves 34, 34.

First, when the left end of the second lock-off button 30 is pushed in and slid rightward, as shown in FIGS. 6 (A) and 7 (A), the protrusion 38 of the engagement tool 35 is moved to the second lock-off button. The arm 32 is locked in the locking groove 34 on the left side of the arm portion 32. In this state, since the protrusions 33 and 33 provided on the arm portion 32 are positioned in front of the protrusions 13 and 13 in the pushing direction of the switch lever 11, even if the switch lever 11 is pushed in, the protrusion The pushing of the switch lever 11 is prevented (lock-off position) by the interference between the protrusion 13 and the protrusion 33.
On the other hand, when the right end of the second lock-off button 30 is pushed in from the lock-off position and is slid to the left, as shown in FIGS. 6 (B) and 7 (B), the protrusion 38 is formed on the right engaging groove 34. Lock to. In this state, since the protrusions 33, 33 of the second lock-off button 30 slide to the left and retract from the front of the protrusions 13, 13, the switch lever 11 can be pushed in (lock-off release position).

  As described above, according to the switch mechanism of the reciprocating saw 1 of the above-described form, the switch 2 is moved in accordance with the depression of the switch lever 11 from the lock-off position where the housing 2 is maintained in the OFF state by the operation from the outside of the housing 2. A first lock-off button 20 that can be moved to a lock-off release position that allows ON and that can be automatically returned to the lock-off position by releasing an operation from the outside of the housing 2; And the second lock-off button 30 that can be moved to the lock-off release position can be selectively assembled, so that the type that the lock-off button automatically returns to the lock-off position and the type that does not automatically return are common. The housing 2 can be selectively assembled. Therefore, it is possible to expect a reduction in management effort and manufacturing costs.

Particularly, since the coil spring 25 is used for the automatic return of the first lock-off button 20 here, the automatic return of the first lock-off button 20 can be easily performed.
Further, since the second lock-off button 30 is engaged with the engagement tool 35 provided in the housing 2 at the lock-off position and the lock-off release position, switching between the lock-off position and the lock-off release position is performed. Can be done reliably.

Further, the first lock-off button 20 maintains the OFF state of the switch 8 by interfering with the switch lever 11 and preventing the pushing operation at the lock-off position, so that the lock-off by the first lock-off button 20 is prevented. It can be done reliably.
Since the coil spring 25 and the engagement tool 35 can be assembled at the same position on the housing 2, the common use of the housing can be maintained even if the coil spring 25 and the engagement tool 35 are used in addition to the lock-off button. This leads to cost reduction.

In addition, the shape of the first lock-off button and the second lock-off button is not limited to the above form, and the cross section is rectangular, the number of ridges is increased or decreased (corresponding to the protrusions of the switch lever corresponding thereto) The elastic body and the engaging member are not limited to the above-described forms. Of course, it is also possible to omit the elastic body and the engaging member and to form an alternative component to the housing. The design of the receiving seat can be changed as appropriate, for example, by omitting one boss 18b and lengthening the other boss 18a.
In the above embodiment, the lock-off member can be slid left and right to select the lock-off position and the lock-off release position. However, the lock-off member can be slid back and forth or up and down to lock and unlock the lock-off position. Can be selected, and the lock-off position and the lock-off release position can be selected by rotating the lock-off member.

The lock-off member is not limited to the case where the lock-off member interferes with the operation member to realize the lock-off, and a lock-off member that is positioned between the switch and the operation member and turns on the switch in conjunction with the pushing operation of the operation member. The present invention can be adopted even with a switch mechanism that realizes lock-off by retracting from between the switch and the operation member.
In addition, in the above embodiment, the switch mechanism of the reciprocating saw has been described, but the present invention is not limited to the reciprocating saw but can be applied to other electric tools, and is not limited to the electric tools, such as air tools and engine tools. It can also be employed in other power tools.

  1. Reciprocating saw, 2. Housing, 3. Left housing, 4. Right housing, 5. Motor, 8. Switch, 9. Plunger, 10. Opening, 11. Switch lever, 13. .. Projection, 14 .. Receiving seat, 15 .. Through hole, 16 .. Tube rib, 17 .. Wall rib, 18 a, 18 b .. Boss, 20 .. First lock-off button (first lock-off member ) 21, 31... Chamfered part, 22, 32.. Arm part, 23, 33 ... Projection, 24 ... Holding part, 25 ... Coil spring, 30 ... Second lock-off button (second Lock-off member), 34 .. locking groove, 35 .. engagement tool, 36 .. through hole, 37 .. end, 38.

Claims (5)

A power tool switch mechanism comprising a switch for operating a prime mover in a housing and an operation member that can be pushed into the switch side,
The housing,
By operating from the outside of the housing, the switch can be moved from a lock-off position for maintaining the OFF state of the switch to a lock-off releasing position that allows the switch to be turned on when the operation member is pushed in, and from the outside of the housing. A first lock-off member capable of automatically returning to the lock-off position by releasing
A second lock-off member movable to the lock-off position and the lock-off release position by an operation from the outside of the housing;
A switch mechanism for a power tool characterized in that each can be selectively assembled.   The switch mechanism for a power tool according to claim 1, wherein an elastic body is used for automatic return of the first lock-off member.   The switch mechanism for a power tool according to claim 2, wherein the second lock-off member is engaged with an engagement member provided in the housing at the lock-off position and the lock-off release position.   4. The switch according to claim 1, wherein the first lock-off member maintains an OFF state of the switch at the lock-off position by interfering with the operation member and preventing the push-in operation. 5. A power tool switch mechanism according to claim 1.   4. The power tool switch mechanism according to claim 3, wherein the elastic body and the engaging member can be assembled at the same position of the housing.

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