JP2004082327A - Power tool - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To make a grip part of the power tool easy to grip by making the grip part fine. <P>SOLUTION: A trigger switch D is composed of an insulating box body 1, a moving contact plate 3, and a trigger lever 2; wherein the insulating box body 1 is composed of a chassis 10 in which a plurality of conductive plates 12 are arranged and a cover 11 attached to the open face of the chassis 10, and the trigger lever 2 is provided with a trigger button 20 and slidably installed in the insulating box body 1. The trigger lever 2 which opens or closes the contact points by swinging the moving contact plate 3 is made to slide freely in the direction along the open face of the chassis 10 and the moving contact plate 3 is set in the direction rectangular to the open face of the chassis 10 and made to swing freely in the installed direction of the trigger lever 2 and the cover 11 against the chassis 10. The trigger switch D is arranged at the grip part C of the power tool A so that the open face of the chassis 11 is arranged along the axial directions of a motor M and of the grip part C. <P>COPYRIGHT: (C)2004,JPO

Description

The present invention relates to a power tool provided with a trigger switch.

2. Description of the Related Art Conventionally, a power tool including a trigger switch has been known. (See Patent Document 1)
When arranging the trigger switch on the power tool, the ease of use of the power tool is improved by arranging the trigger switch on the grip part of the power tool.However, the trigger switch has a complicated structure and is large in size as a switch. If the trigger switch is incorporated in the grip portion of the electric tool, the grip portion becomes thicker, it is difficult to hold the grip portion, and the usability of the electric tool deteriorates.

Further, as described above, the trigger switch used for the electric tool is an insulated housing including a movable contact plate having a movable contact and a plurality of conductive plates, and a trigger button provided at one end and slid into the insulated housing. The movable contact plate, which comprises a trigger lever which is freely held and which is arranged so as to be capable of seesaw movement on a support piece provided on the conductive plate, performs a seesaw movement in accordance with the sliding operation of the lever, thereby providing a movable contact. And a fixed contact provided on another conductive plate.

Conventionally, the conductive plate is assembled to the chassis of the chassis and the cover that constitute the insulating housing, and the movable contact plate is arranged. Thereafter, the lever is incorporated and the cover is attached to the chassis, or the assembly is performed. The housing is composed of two chassis and a cover, a conductive plate is mounted on the first chassis, a movable contact plate is arranged, a lever and a conductive plate are mounted on the second chassis, and both chassis are overlapped. The cover was assembled and assembled.

In the former conventional example, the conductive plate must first be assembled to the chassis, and the direction in which the movable contact plate and lever are mounted on the chassis is different from the direction in which the conductive plate and other parts are mounted on the chassis. Therefore, there is a problem that the assemblability is poor. Even in the latter conventional example having a plurality of chassis, the mounting of the conductive plate is also necessary, and the mounting directions of the parts to each chassis are different, and furthermore, by connecting the plurality of chassis and attaching the cover, It takes time and effort to assemble the parts into a single unit, and also has a problem that the assemblability is poor.

Incorporating other switches for polarity switching, etc., in the insulated housing, or incorporating a circuit for motor speed control, the number of components to be incorporated is increased. I have.
JP-B-63-35042

SUMMARY OF THE INVENTION The present invention has been made in view of the above-described conventional problems, and a small and thin trigger switch having good assemblability can be incorporated into a grip portion to make the grip portion thin and easy to grip. It is another object of the present invention to provide a power tool that can reduce the price.

An electric tool according to the present invention includes a motor, a power source, a reduction gear, a trigger switch, and a speed control circuit. An insulating housing comprising a chassis on which the plate is disposed and a cover attached to the opening surface of the chassis; a movable contact opposed to a fixed contact provided on the conductive plate at one end; It comprises a movable contact plate movably supported, and a trigger lever slidably attached to an insulated housing with a trigger button at one end, and a movable contact plate with a driving unit for the movable contact plate. The trigger lever that swings the plate to open and close the contact is slidable in the direction along the opening surface of the chassis, and the movable contact plate is The trigger switch, which is orthogonal to the opening of the chassis and is swingable in the direction of assembling the trigger lever and the cover with respect to the chassis, is moved along the axial direction of the motor and the axial direction of the grip portion, respectively. Is arranged on the grip portion as described above.

As described above, the trigger switch incorporated in the grip portion of the power tool is configured such that the swing direction of the movable contact plate is a direction orthogonal to the opening surface of the chassis and the assembly direction of the trigger lever and the cover with respect to the chassis is an insulating housing. The small and thin trigger switch can be formed with a grip portion such that the opening surface of the chassis extends along the axial direction of the motor and the axial direction of the grip portion, respectively. Since the trigger switch is installed in the grip part, the grip part can be made thin and easy to grasp, despite the fact that the trigger switch is incorporated in the grip part, and the trigger switch incorporated in the grip part of the power tool is Assemble the trigger lever, movable contact plate and cover to the chassis as described above. Since the assembly is performed in the same direction from the side of the opening, the assembly workability is excellent, and the swing direction of the movable contact plate is perpendicular to the opening of the chassis, and the trigger lever and the cover are assembled to the chassis. Since the movable contact plate can be supported so that it can swing freely, it is only necessary to dispose the movable contact plate in the above-mentioned mounting direction, and it is extremely easy to assemble. In addition, the cost can be reduced and the cost can be reduced, whereby the power tool incorporating the trigger switch can be reduced in price.

Further, a trigger switch arranged on the grip portion operates the speed control circuit at the beginning of the stroke of the trigger button to control the speed of the motor, and operates the motor at the end of the stroke without operation of the speed control circuit. Preferably, two movable contact plates for turning on and off the motor and for turning on and off the speed control circuit are arranged to be swingable, and the two movable contact plates are provided on the insulating casing. By arranging in the direction intersecting the thickness direction, it is possible to say that two movable contact plates are provided, but the thickness of the insulating housing can be reduced, which makes the grip of the power tool thinner and easier to grip It becomes.

Also, by exposing a part of the conductive plate on the inner surface side of the chassis of the trigger switch or projecting an integral protrusion from the conductive plate, a supporting piece for swinging the movable contact plate, a pair of supporting pieces for mounting the diode, It is preferable that a fixed contact mounting portion is formed.

With this configuration, the movable contact plate, the diode, and the fixed contact can be attached to the chassis on which the conductive plate is provided from the opening side of the chassis, so that the assembling work can be easily performed. Further, it is preferable that a pair of support pieces for mounting a diode of the trigger switch project in the direction of the opening of the chassis, and a diode is mounted on the pair of support pieces from the side of the opening of the chassis.

With this configuration, the diode can be easily attached to the pair of support pieces projecting in the direction of the opening surface of the chassis from the opening surface side.

Preferably, a partition formed integrally with the chassis is provided between the arrangement portions of the two movable contact plates in the insulating housing of the trigger switch.

構成 With such a configuration, the partition wall can improve insulation and dust resistance between the arrangement portions of both movable contact plates and improve rigidity of the chassis.

Preferably, in the insulating housing of the trigger switch, the arrangement portion of the diode and the arrangement portion of the movable contact plate are separated by a partition formed integrally with the chassis.

構成 With such a configuration, it is possible to improve insulation and dust resistance between the arrangement portion of the diode and the arrangement portion of the movable contact plate, and to improve the rigidity of the chassis.

可 動 It is preferable that the movable contact plate is disposed on the inner side in the mounting direction of the trigger lever in the insulating housing of the trigger switch.

With such a configuration, the assembling work can be performed in the same direction from the opening surface side of the chassis, such that the movable contact plate is assembled after the movable contact is assembled from the opening surface of the insulating casing.

Preferably, the trigger lever has a contact spring that contacts a resistor formed on a substrate of the speed control circuit to form a variable resistor for controlling the speed of the motor, and a slider that slides on the movable contact plate. .

It is preferable to have a switch for turning on / off the power supply and a switch for bypassing the speed control circuit, the on / off operation of which is controlled by the slider on the movable contact plate by moving together with the trigger lever.

The present invention can provide a power tool that is thin and easy to grip, despite the fact that the trigger switch is incorporated in the grip. In addition, the trigger switch incorporated in the grip portion of the power tool is excellent in assembling work because the trigger lever, the movable contact plate, and the cover are assembled to the chassis in the same direction from the opening side of the chassis as described above. In addition, since the swing direction of the movable contact plate is the direction orthogonal to the opening surface of the chassis and the assembly direction of the trigger lever and the cover with respect to the chassis, the movable contact plate can be swingably supported. It is only necessary to dispose the movable contact plate in the above-mentioned mounting direction, and it is possible to assemble it very easily, and to reduce the cost and reduce the price. This makes it possible to reduce the price of the built-in power tool.

Hereinafter, the present invention will be described based on embodiments shown in the accompanying drawings.

FIG. 1 shows an electric tool A, which is provided with a motor M, a reduction gear G, and a battery pack B as a power source. A trigger switch D is incorporated in a grip portion C of the electric tool A.

ト リ ガ ー The trigger switch D incorporated in the grip C of the power tool A has the following configuration.

The trigger switch D in the illustrated example is configured to control the motor M that is the power source of the power tool A, and also incorporates a changeover switch for switching the rotation direction of the motor M and a speed control circuit of the motor M. As shown in FIGS. 2 and 3, a switching lever 4 is provided on the upper surface of the insulating casing 1, and a trigger button 20 is attached to a tip of the trigger lever 2 protruding from the front side. Connection terminals 18 and 19 for connecting a motor M and a battery pack (battery) B as a power source are provided on the upper and lower surfaces, respectively. In the figure, reference numeral 70 denotes a battery connection fitting.

As shown in FIG. 5, the insulating housing 1 includes a box-shaped chassis 10 having one side opening and a cover 11 that covers the opening of the chassis 10. As shown, a plurality of conductive plates 12 are embedded in a portion to be the other side surface by integral molding, and the connection terminals 18 and 19 are formed as a part of these conductive plates 12. Also, a part of the conductive plate 12 is exposed on the inner surface side of the chassis 10 or an integral protrusion protrudes from the conductive plate 12, so that the support pieces 13, 13 for supporting the movable contact plate 3, and a pair of The connection pieces 14, 14, the fixed contact mounting portion 15, the connection terminal portions 16, 16 and the like are formed. A fixed contact 71 is fixed to the fixed contact mounting portion 15 by caulking, and a lead wire 56 for connection to a switching element 55 for speed control is connected to the connection terminal portion 16 by a caulking pin 59.

(2) In the illustrated example, two movable contact plates 3 are provided for turning on / off the load and turning on / off the speed control circuit. The two movable contact plates 3, 3 are mounted on the chassis 10 so as to be swingable by being supported by the support pieces 13, 13. However, the movable contact plates arranged vertically in the drawing. The swing directions of the movable contact plates 3 and 3 are orthogonal to the opening surface of the chassis 10, so that the movable contact plates 3 and 3 can be assembled only by inserting and inserting from the opening surface side of the chassis 10. .

As shown in FIGS. 2 and 6 (c), the trigger lever 2 provided with the trigger button 20 at one end is spring-biased sliding that comes into sliding contact with the surfaces of the two movable contact plates 3 and 3. The housing 21 is provided on the side surface thereof, and is slidable with respect to the insulating casing 1 in a direction along the opening surface of the chassis 10, and is provided with a return spring 22 disposed between the insulating casing 1 and a side wall of the chassis 10. The spring is biased in the direction in which the trigger button 20 projects. Further, a contact spring 23 is fixed to the trigger lever 2. The contact spring 23 makes contact with a pattern on the substrate 5 of the speed control circuit described later to form a variable resistor. In the figure, reference numeral 24 denotes a dustproof O-ring.

Here, the trigger lever 2 to be sandwiched between the chassis 10 and the cover 11 of the insulating casing 1 is disposed from the opening side of the chassis 10 like the movable contact plates 3 and 3 and then the cover lever 11 is closed. The trigger lever 2 thus assembled changes the contact point of the sliders 22, 22 on the surfaces of the movable contact plates 3, 3 with the sliding operation. Then, when the contact point crosses the position of the support piece 13, the movable contact plate 3 swings (seesaw movement) with the support piece 13 as a fulcrum, and the movable contact 30 provided on the movable contact plate 3 The contact with and separation from the fixed contact 71 are performed.

Note that, of the two movable contact plates 3, 3, the support piece 13 serving as the fulcrum of the upper movable contact plate 3 in the figure is more trigger button than the support piece 13 for the other movable contact plate 3. When the trigger button 20 is pulled and the trigger lever 2 is slid against the return spring 22 because of being on the 20 side, first, the movable contact 30 and the fixed contact 71 of the upper movable contact plate 3 close, and then The movable contact 30 and the fixed contact 71 of the lower movable contact plate 3 are closed.

As described above, the trigger switch D also incorporates a changeover switch for switching the rotation direction of the motor and a speed control circuit of the motor. The changeover switch is provided on the upper side of the insulating casing 1. The speed control circuit is housed in the lower part of the insulating housing 1, and these housing parts are partitioned by the partition 17 formed integrally with the chassis 10 in the insulating housing 1. A partition wall 17 is also provided between the arrangement portions of the movable contact plates 3 and 3.

The changeover switch will be described. The changeover switch performs a contact changeover by rotating a changeover lever 4 disposed on the upper end surface of the insulating casing 1, and the changeover lever 4 here, as shown in FIG. A boss 40 is provided at one end, an interlocking shaft 41 is provided at an intermediate position, and an engagement piece 42 is provided at the other end. The boss 40 is inserted into a shaft hole 80 formed in the upper surface of the chassis 10 so that the boss 40 is centered. Is rotatable.

{Circle around (4)} In the upper part of the insulating casing 1, a cam 43 that rotates in conjunction with the switching lever 4 and a sliding body 46 that is slidable in the same direction as the trigger lever 2 are provided. The cam 43 here is rotatable when its shaft 44 is supported by the chassis 10, and is projected from one of the two cutouts 45, 45 provided on the peripheral surface from the switching lever 4. At the same time, the interlocking shaft 41 located in the chassis 10 engages through the arc-shaped long hole 81 provided in the chassis 10 and rotates with the rotation of the switching lever 4.

As shown in FIGS. 6 (b) and 9 (a), the sliding body 46 has a pair of spring-biased contact plates 48, 48 attached thereto and a click projection 49 attached thereto. A shaft 47 is provided for engaging with the other notch 45 of the cam 43, and performs a sliding operation as the cam 43 rotates. At the time of this sliding, the contact plates 48, 48 change the short-circuit relationship between the switching contacts formed as the exposed portions of the plurality of conductive plates 12 at the back of the arrangement portion of the sliding body 46, and at this time, the click protrusion The click 49 generates a click by engaging with a click recess 85 formed on the inner surface of the cover 11. FIG. 9 shows the state at the neutral position, and FIG. 10 shows the state switched to one side. When the switching lever 4 is moved upward in FIG. 9, the sliding body 46 moves rightward in the figure and the other side moves. Switch to the side. When the engagement piece 42 of the switching lever 4 is in the neutral position, it is located on the movement locus of the stopper 28 of the trigger button 20 to prevent the trigger button 20 from being pulled. This locks the trigger lever 2.

(4) The board 5 and the protection diode 54 are housed in the speed control circuit housing section on the lower side of the insulating housing 1. The board 5 is attached to the chassis 10 by soldering the connection terminals 53 on the side edges shown in FIG. 5 from the opening side of the chassis 10 to the connection portions 80 of the conductive plate 12 of the chassis 10, and the diode 54 is connected to the chassis 10. It is attached by being caulked to the tip of the support piece 14 that stands up. The switching element 55 in the speed control circuit is externally attached for heat radiation, and two of the three lead wires 56 derived from the switching element 55 are connected to the connection terminals 16, 16. You. The remaining one lead wire 56 is inserted and connected to a connection portion of the board 5 through a hole formed in the chassis 10.

After the above components are assembled to the chassis 10, the cover 11 is put on the opening surface of the chassis 10, and the cover 11 and the chassis 10 are connected by the hooks 75 to close the opening surface of the chassis 10. However, components such as the movable contact plate 3, the trigger lever 2, the return spring 22, the cam 43, the sliding body 46, the substrate 5, and the diode 54 are arranged on the chassis 10 in which the conductive plate 12 is embedded from the opening side of the chassis 10. In addition to the mounting, the movable contact plate 3, which is a movable component, can be moved only in a direction perpendicular to the opening surface. Since the cover 11 can be attached from the same direction, the assembling work can be easily performed. Further, since the components are assembled in the same direction, even if the inside of the chassis 10 is partitioned by the partition walls 17, the assemblability is not deteriorated. And the rigidity of the chassis 10 can be improved. Further, although the trigger lever 2 and the movable contact plate 3 are arranged in the thickness direction of the insulating casing 1, the operation direction of the movable contact plate 3 is Since the two movable contact plates 3 are set as described above and are arranged in a direction intersecting the thickness direction of the insulating casing 1, the thickness of the insulating casing 1 can be kept thin.

Fig. 11 shows a circuit diagram. In the figure, SW is a changeover switch, S1 is an on / off switch composed of the upper movable contact plate 3, and S2 is a speed control on / off switch composed of the lower movable contact plate 3. When the trigger button 20 is depressed, first, the switch S1 is turned on to energize the motor which is a load in a state where the speed control circuit is effective. As the trigger button 20 is depressed, the contact between the contact plate 23 and the substrate 5 is increased. When the resistance value of the formed variable resistor changes, the rotation speed of the motor increases, and when the switch S2 is turned on, the speed control circuit is bypassed and the motor is energized.

The trigger switch D having the above-described structure, which is easy to assemble, is small, and has a small thickness of the insulating casing 1 is incorporated in the grip portion C of the electric tool A as shown in FIG. As shown in FIG. 5, the opening surface of the chassis 10 is incorporated and arranged in the grip C so that the axial direction of the motor M of the electric tool A and the axial direction of the grip C are respectively aligned. As described above, by incorporating the trigger switch D having a small thickness of the insulating casing 1 into the grip portion C of the power tool A as described above, the grip portion C can be made thin and easy to grip.

The hook 86 formed on the side wall of the cover 11 of the trigger switch D is for holding the lead wire 56 connected to the switching element 55, and the trigger switch D is connected to the power tool A. The handleability when incorporating is improved. The reason why the corners of the insulating casing 1 are formed as inclined surfaces is that, when the trigger switch D is disposed on the grip portion C of the power tool A as shown in FIG. This is for avoiding interference with the grip portion C that projects in an oblique direction, and therefore contributes to the miniaturization of the grip portion C.

It is a fracture side view showing the state where a trigger switch was built into a grip part of an electric power tool of the present invention. It is a front view in the state where the cover of the insulating case was removed in one embodiment of the trigger switch built into the grip part of the power tool. 5A is a left side view, FIG. 5B is a front view, and FIG. 5C is a right side view. It is a top view of a trigger switch. It is a partially omitted exploded perspective view of a trigger switch. (A) is a perspective view of a switching lever and a cam in the changeover switch, (b) is an exploded perspective view of a sliding body, and (c) is an exploded perspective view of a trigger lever. It is a front view of a chassis. It is a front view showing the state where a movable contact plate was attached to a chassis. (A), (b) is a horizontal sectional view of the changeover switch in a neutral position. (A), (b) is a horizontal sectional view of a changeover switch when switching is performed in one direction. It is a circuit diagram.

Explanation of reference numerals

Reference Signs List A power tool B battery pack C grip part D trigger switch G reduction gear M motor 1 insulating housing 2 trigger lever 3 movable contact plate 10 chassis 11 cover 12 conductive plate 20 trigger button

Claims (10)

In a power tool including a motor, a power supply, a reduction gear, a trigger switch, and a speed control circuit, and the trigger switch is arranged in the grip portion,
An insulating housing comprising a chassis on which a plurality of conductive plates are disposed and a cover attached to an opening surface of the chassis, and a movable contact opposed to a fixed contact provided on the conductive plate provided at one end; It consists of a movable contact plate swingably supported by a conductive plate, and a trigger lever slidably attached to an insulating housing with a trigger button at one end. A trigger lever that swings the movable contact plate to open and close the contacts with the movable contact plate is slidable in a direction along the opening surface of the chassis, and the movable contact plate is in a direction orthogonal to the opening surface of the chassis and The trigger switch, which is swingable in the direction of assembling the trigger lever and the cover with respect to the chassis, is mounted on the chassis. Power tool, characterized in that along the axial direction respectively are arranged on the grip portion. A trigger switch disposed on the grip portion operates the speed control circuit at the beginning of the stroke of the trigger button to execute speed control of the motor, and operates the motor at the end of the stroke without operation of the speed control circuit, 2. The power tool according to claim 1, wherein two movable contact plates for turning on and off the motor and for turning on and off the speed control circuit are swingably disposed. 3. The power tool according to claim 2, wherein the two movable contact plates are arranged in a direction intersecting the thickness direction of the insulating casing. By exposing a part of the conductive plate on the inner surface side of the chassis of the trigger switch, or by projecting an integral protrusion from the conductive plate, a supporting piece for swinging the movable contact plate, a pair of supporting pieces for mounting the diode and a fixed contact. The power tool according to claim 1, wherein the power tool has a mounting portion. 5. The power tool according to claim 4, wherein a pair of support pieces for mounting a diode of the trigger switch project in a direction of an opening surface of the chassis, and a diode is mounted on the pair of support pieces from an opening surface side of the chassis. . 2. The power tool according to claim 1, wherein a partition formed integrally with the chassis is provided between the disposition portions of the movable contact plates in the insulating housing of the trigger switch. The power tool according to claim 1, wherein, within the insulating housing of the trigger switch, the arrangement portion of the diode and the arrangement portion of the movable contact plate are separated by a partition formed integrally with the chassis. The power tool according to claim 1, wherein a movable contact plate is disposed on the inner side of the trigger switch in the mounting direction of the trigger lever in the insulating housing of the trigger switch. The trigger lever has a contact spring that contacts a resistor formed on the substrate of the speed control circuit to form a variable resistor for controlling the speed of the motor, and a slider that slides on the movable contact plate. The power tool according to claim 1. 2. The power supply according to claim 1, further comprising a switch for turning on / off a power supply and a switch for bypassing a speed control circuit, the on / off operation being controlled by a slider on a movable contact plate by moving together with the trigger lever. Electric tool.

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