JPH0415968B2 - - Google Patents

Description

[Detailed Description of the Invention] (a) Field of Industrial Application The present invention relates to a changeover switch used for forward/reverse rotation of various power tools such as electric screwdrivers, electric drills, electric saws, etc. The present invention relates to a changeover switch that can be arranged compactly and efficiently in a power tool.

(B) Prior Art Generally, in this type of changeover switch, a pair of changeover switch for switching the motor between forward and reverse directions and an overcurrent relay for protecting the motor section are disposed in the power tool.

However, in power tools, changeover switches and overcurrent relays are usually installed separately and independently, which makes storage inefficient, and the storage space is limited, making assembly difficult. This has led to the problem that the power tool becomes larger due to the increase in the storage space of the assembly section.

(c) Problems to be Solved by the Invention The present invention provides a switching system in which a support structure for an overcurrent relay can be easily obtained, and in which both a changeover switch and an overcurrent relay can be arranged in a well-balanced manner to form a compact integrated structure. The purpose is to provide a switch.

(d) Means for Solving the Problems The present invention provides a changeover switch in which a switch base is provided with a plurality of lead terminals connected to contact members constituting the changeover switch, and among the lead terminals, an overcurrent relay The lead terminals other than the overcurrent relay lead terminal to which the overcurrent relay is connected are extended outward from one long side of the switch base and insert-molded, and the overcurrent relay lead terminal and the overcurrent relay are connected together. A support member to be supported is extended to the outside from the other long side of the switch base and insert molded, and both ends of the overcurrent relay are fixed between the extensions of the overcurrent relay lead terminal and the support member. It is characterized in that it is a connected changeover switch.

(E) Effects of the Invention According to this invention, the support structure for supporting an overcurrent relay includes a support member that is simultaneously formed using insert molding of lead terminals, and an insert molded lead terminal for the overcurrent relay. Therefore, the support structure can be formed simultaneously with the insert molding of the lead terminal, thereby simplifying the formation.

Furthermore, attach the lead terminals other than the overcurrent relay lead terminals to one long side of the switch base.
Since the overcurrent relays are placed on the same side, the arrangement of the switch body, other lead terminals, and overcurrent relays is balanced in a substantially rectangular plan view, making it possible to compactly integrate them. By placing the overcurrent relay on the side of the switch, the thickness can be reduced and even more compact integration can be achieved.

As a result, when this changeover switch is incorporated into a power tool, for example, it can be efficiently incorporated into the internal storage space, simplifying assembly into the power tool, and reducing the storage space inside the power tool. As a result, the power tool can be reliably downsized, and these parts can also be easily managed and handled.

(F) Embodiment of the Invention An embodiment of the invention will be described in detail below based on the drawings.

The drawings show a changeover switch used for forward/reverse operation of a power tool, and in Figures 1 to 4, this changeover switch is
1, overcurrent relay 12, and movable contact piece 13, 1
3, slider 14, leaf spring 15, switch cover 16, dustproof sheet 17, and operation knob 18
It consists of

The switch base 11 described above is provided in a square shape by insert molding with the first to fifth lead terminals 19 to 22, 19a and the support piece 23 arranged in parallel, and the upper surface accommodates a movable contact piece to be described later. It has a possible recess 24, flush with the upper surface within this recess 24,
The inserted upper surfaces of these terminals 19 to 22, 19a are exposed in parallel at the same pitch, and each of these exposed surfaces comes into sliding contact with a movable contact piece to be described later.

In this case, the first lead terminal 19 and the fifth lead terminal 19a are electrically connected and disposed as a common terminal in parallel on both sides of the second to fourth lead terminals 20 to 22.

The above-described second to fourth lead terminals 20 to 22 project horizontally from one side of the long side of the base, and a C-shaped lead wire connection hole 25 is cut out in the projecting portion.

Further, on the other side surface on the long side, a first lead terminal 19 is extended on one side, and a support piece 23 as a support member is extended on the other side, and these extended tips are bent upward. A V-shaped notch 2 is provided at the rising end of the bent first lead terminal 19.
6, and an L is formed at the rising end of the support piece 23.
A shaped notch 27 is formed, and both of these notches 2
Terminals 28 and 29 provided on both sides of the overcurrent relay 12 are connected to terminals 6 and 27 by soldering, respectively. A lead wire 30 for connecting the motor is connected to a terminal 29 provided on one side of the overcurrent relay 12.

Note that the above-mentioned overcurrent relay 12 is made of, for example, bimetal.

Also, in the center of both sides of the short side of the base, locking portions 31 and 3 corresponding to the switch locking portion of the power tool are provided.
1 is formed, and furthermore, on both sides of the locking part 31, projections 32 for attaching a switch cover, which will be described later, are formed.
is prominent.

The aforementioned movable contact piece 13 is provided in a W shape,
At the center of the upper surface of this W shape, there is a rocking permitting protrusion 33.
A W-shaped bottom part is provided on the lower surface of the terminal so as to extend over both sides of the lead terminals arranged in parallel and contact each other at two points on both sides.

The W-shaped movable contact pieces 13 are provided in a pair on the left and right, and are housed in the recess 24 of the switch base 11, and are slid in the longitudinal direction within the recess 24 by the sliding action of a slider, which will be described later. be done. By this sliding operation, the contact positions of the pair of movable contact pieces 13, 13 corresponding to the first to fifth lead terminals 19 to 22, 19a are variably operated, and the direction of current flow is switched.

In this case, one movable contact piece 13 is
The other movable contact piece 13 slides between the lead terminals 19 to 21 and the third to fifth lead terminals 21 to 21.
19a.

The slider 14 described above has a convex portion 34 on the lower surface that can be slid and fitted into the concave portion 24 of the switch base, and an engagement member is provided in the convex portion 34 to press down and support the movable contact pieces 13, 13. A pair of left and right recesses 35 are formed, and a protrusion corresponding hole 36 into which the above-mentioned swinging permitting protrusion 33 is fitted is formed in the center of the engaging recesses 35, 35. The allowable protrusion 33 is fitted to support the movable contact piece 13 at one point. The movable contact piece 13 supported thereby is allowed to swing in any direction about the swing allowing protrusion 33 as a fulcrum when sliding, thereby achieving a smooth sliding action.

Furthermore, a fitting recess 37 is formed on the top surface for fitting a leaf spring, which will be described later, and a slide shaft 38 is provided protruding from the center of the top surface to engage with an operating knob, which will be described later.

The above-mentioned leaf spring 15 is provided in an F-shape and is housed in a fitting recess 37 of the slider.A through hole 39 passing through the slide shaft 38 is opened in the center of the F-shape, and a through hole 39 is formed in the central bent part. A circular arc-shaped protrusion 40 is formed in a protruding manner, and this arc-shaped protrusion 40 is engaged with a touch-sensitive portion of a switch cover, which will be described later.

The above-mentioned switch cover 16 is provided in a box shape with an open bottom surface, and a pair of left and right feel corresponding parts 41, 41 are provided in the sliding direction at the center of the bottom surface of the box shape.
is engraved, and when the above-mentioned arcuate protrusion 40 slides, it engages with one of the feel corresponding parts 41 to accurately position the slider 14, and also allows the switch to be changed by sliding. is transmitted to the operating knob to be described later through the elastic action of the leaf spring 15.

Furthermore, a slide hole 42 for allowing the above-mentioned slide shaft 38 to protrude upward is provided in the center of the cover, and connecting pieces 4 are provided at the bottom of both sides of the short side.
3 are provided vertically, and the engaging portions carved on the inner surfaces of these connecting pieces 43 engage with the protrusions 32 of the switch base, thereby allowing the switch cover 16 to move the leaf spring 15 upward. It is integrally connected to the switch base 11 so as to cover the switch base 11 in a slightly compressed state.

The aforementioned operation knob 18 has a knob 44 at the center of the top surface.
A slide shaft engaging portion 45 is formed on the lower surface thereof, and the upper end portion of the slide shaft 38 protruding through the slide hole 42 of the switch cover 16 is integrally engaged with the slide shaft engaging portion 45. The switch cover 16 is then slidably attached to the switch cover 16 via a dustproof sheet 17.

In the changeover switch configured in this way, by sliding the operation knob 18 to one side, one of the movable contact pieces 13 is switched between the first lead terminal 19 and the second lead terminal.
The other movable contact piece 13 straddles and contacts both the third lead terminal 21 and the fourth lead terminal 22.
As a result, for example, one current flows from the second lead terminal 20 to the first lead terminal 19, and the other current flows from the fourth lead terminal 22 to the third lead terminal 21.
The motor is driven to rotate in the forward direction.

When the operating knob 18 is slid to the other side, one of the movable contact pieces 13 comes into contact with both the second lead terminal 20 and the third lead terminal 21, and the other movable contact piece 13 contacts both the fourth lead terminal 22 and the fifth lead terminal 19a. As a result, one current flows from the second lead terminal 20 to the third lead terminal 21, and the other current flows from the fourth lead terminal 22 to the fifth lead terminal 19a, and the motor is driven to rotate in reverse.

By the way, when installing this changeover switch on a power tool, simply attach it to the changeover switch mounting part inside the power tool, and since the overcurrent relay 12 is integrated with it, you can install it at the same time.
An independent storage space corresponding to the overcurrent relay 12 is not required, and the overcurrent relay 12 can be efficiently disposed within the power tool.

Note that when the current flowing through the overcurrent relay 12 exceeds the set value, the overcurrent relay 1
2 is activated.

FIG. 5 shows another embodiment of the present invention, in which lead terminals 5 extending from both ends of the switch base 51 are shown.
2, 53, both terminals 55, 56 of the overcurrent relay 54
and one lead terminal 5.
3 may be provided with a lead wire connection hole 57, and a lead wire 58 may be directly connected to the lead wire connection hole 57, so that one lead terminal 53 of the switch base 51 may be provided in a structure that serves both as a support piece and a lead terminal.

As mentioned above, since the overcurrent relay is integrally fixed to a part of the switch base that constitutes the changeover switch, it is not only easy to handle and assemble to the power tool, but also easy to assemble to the power tool. The internal storage space can be reduced for efficient storage.

Regarding the correspondence between the structure of this invention and the above-described embodiments, the case of this invention corresponds to the switch bases 11 and 51 of the embodiments, and similarly, the overcurrent relay corresponds to the overcurrent relays 12 and 54. The contact member corresponds to the movable contact piece 13, and the lead terminals correspond to the first to fifth lead terminals 19 to 2.
2 and 19a and the lead terminals 52 and 53, and the support member corresponds to the support piece 23. However, the present invention is not limited to the configuration of the above-described embodiment.

[Brief explanation of drawings]

The drawings show an embodiment of the present invention; FIG. 1 is an exploded perspective view of a changeover switch, FIG. 2 is a partially cutaway plan view of the changeover switch, FIG. 3 is a vertical sectional view of the changeover switch, and FIG. FIG. 5 is an exploded perspective view of a changeover switch showing another embodiment of the present invention. 11,51...Switch base, 12,54...
...Overcurrent relay, 13...Movable contact piece, 19,1
9a, 20, 21, 22, 52, 53...Lead terminal, 23...Support piece.

Claims (1)

[Scope of Claims] 1. A changeover switch comprising a switch base having a plurality of lead terminals connected to contact members constituting the changeover switch, wherein among the lead terminals, one for an overcurrent relay to be connected to an overcurrent relay is provided. Other lead terminals other than the lead terminal are extended outward from one long side of the switch base and insert molded, and the overcurrent relay lead terminal and the support member for supporting the overcurrent relay are attached to the switch base. A changeover switch which is insert-molded and extends outward from the other long side of the switch, and has both ends of the overcurrent relay fixedly connected between the extension of the lead terminal for the overcurrent relay and the support member.