JP5564399B2 - Forward / reverse switch for power tools - Google Patents

Description

  BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a forward / reverse switching switch for an electric tool, and more specifically, a seesaw-type movable contact piece is employed in a changeover switch for switching forward / reverse rotation of a motor used in an AC power tool. The present invention relates to a forward / reverse switch for a power tool that uses a spring-reversed sea-source ride mechanism to generate pressure / switching feeling.

  There are various forward / reverse changeover switch mechanisms for switching between forward and reverse rotation of the motor in the prior art, and it can be roughly divided to switch the circuit by the sliding movement of the movable contact piece to switch between forward and reverse rotation of the motor. There is a forward / reverse changeover switch having a structure or a structure for switching forward / reverse rotation of a motor by a seesaw operation of a movable contact piece.

  The forward / reverse switching switch of the first example is a switch having a structure in which the movable contact piece slides, and as shown in FIG. 6, a circuit for controlling the motor and the like are incorporated as a whole. A switch main body 111, a switch switch 113 mounted on the switch main body 111 for switching between forward and reverse rotation of the motor by a switch lever 112, a trigger 114 connected to the switch main body 111 via a slide shaft, and the like. Has been.

  As shown in FIG. 7, the changeover switch portion 113 is formed of a resin and is formed in a substantially rectangular parallelepiped shape. A changeover case 115 in which plate-like fixed contact pieces are arranged in an alignment state therein, and an abbreviation of the changeover case 115. A rotating part 116 formed in a cylindrical shape that is rotatably arranged at the center position, and a first movable contact accommodated in a first movable contact piece accommodating part 117 formed on a side wall surface of the rotating part 116. More than the position where the second movable contact piece 121 and the first movable contact piece 118 are mounted in the same position as the first movable contact piece 118 at the opposite position where the piece 118 and the first movable contact piece 118 are arranged. On the upper part of the pivoting spring 116 and the pivoting spring 119b that engages with the crimping hole 119 provided on the left side at the upper part, the central shaft hole 123 that engages the central shaft 125 that protrudes from the upper end of the pivoting part 116, and the pivoting part 116. Projection at an eccentric position A rotating bar guide groove 127 for engaging and guiding the rotating bar 126 is provided, and as shown in FIG. 8A, the space for engaging the rotating part 116 on the back side and the boss 119b give a feeling of feeling. A cover 124 having a rotation accommodating portion 128 having a rocker rotation portion 129 that is a space formed in a substantially square shape, and a rotation bar 126 formed in a disc shape and penetrating the rotation bar guide groove 127. This is generally composed of a communication hole 136 for communication and a rotation cover 131 having a center hole 121 for engaging the center shaft 125.

  The switching case 115 includes four first, second, third, and fourth fixed contact pieces 132, 133, and 134 that are arranged in an aligned state with contact surfaces formed in a flat plate shape at predetermined intervals on the left, right, and top. , 135.

  The rotating part 116 is formed in a substantially cylindrical shape, and as described above, the first movable contact piece housing formed by recessing in the space for housing the first movable contact piece spring 120a and the first movable contact piece 118 on the side wall surface. The second movable contact piece accommodating portion 122 formed in a space for accommodating the second movable contact piece spring 120b and the second movable contact piece 121 is provided on the opposite side wall surface. A pivot bar 119 is provided with a center hole 125 provided at the upper left side of the contact piece receiving portion 117, and has a center shaft 125 that protrudes from the upper end to the central position. The pivot bar is also guided by the switching lever 112 to an eccentric position at the upper end. 126 is provided.

  The first movable contact piece 118 is formed in a substantially T-shape, and has a contact portion 118b that is bent and extended at right angles to both sides with respect to the central support portion 118a. The structure is bent in the direction.

  The second movable contact piece 121 has the same shape as the first movable contact piece 118, is formed in a substantially T shape, and has a contact portion 121b that is bent and extended at right angles to both sides of the central support portion 121a. The contact portion 121b has a structure in which a tip end portion is bent upward.

  As described in part above, the cover 124 is provided with a rotating cover groove 130 formed in a recessed shape for mounting the disk-shaped rotating cover 131 on the surface side, and on the opposite side of the rotating cover groove 130. A rotating portion accommodating portion 128 formed in a cylindrical shape having a size for accommodating the rotating portion 116 is provided on the back surface, and an oscillating rotating portion 129 having corners at both ends is provided continuously to the rotating portion accommodating portion 128. It has a structure.

  In order to house these parts in the cover 124 and assemble them into the switching case 115, first, the first movable contact piece spring 120 a and the first movable contact piece 118 are placed in the first movable contact piece receiving portion 117 of the rotating portion 116. The second movable contact piece spring 120b and the second movable contact piece 121 are housed in the second movable contact piece housing portion 122, the rocking spring hole 119 is housed in the rocking spring 119a and the rocking bar 119b, and the cover 124 is rotated. It is accommodated in the accommodating part 128. Then, the rotation cover 131 is attached to the rotation cover groove 130 on the surface in which the center shaft 125 is engaged with the center shaft hole 123 and the rotation bar 126 is engaged with the rotation bar guide groove 127, and the rotation cover 131 is mounted thereon. A switching lever 112 is attached.

  In the change-over switch unit assembled in this way, as shown in FIG. 8A, when the motor rotates in the normal direction, the contact point of the first movable contact piece 118 attached to the rotation unit 116 is used. The portion 118b is in contact with the contact surfaces of the second fixed contact piece 133 and the fourth fixed contact piece 135, and the contact portion 121b of the second movable contact piece 121 is in contact with the first fixed contact piece 132 and the third fixed contact piece 134. It is in a state of being in contact with the contact surface, and the basin 119b is in a state of being positioned at the right corner of the basin rotation unit 129.

  In order to reverse the rotation of the motor, as shown in FIG. 8 (B), the switching lever 112 is rotated to rotate the rotating unit 116. The second movable contact pieces 118 and 121 move while sliding on the contact surfaces of the first, second, third and fourth fixed contact pieces 132, 133, 134 and 135. Then, the contact portion 118b of the first movable contact piece 118 comes into contact with the contact surfaces of the third fixed contact piece 134 and the fourth fixed contact piece 135, and the contact portion 121b of the second movable contact piece 121 is in contact with the first fixed contact. The state comes into contact with the contact surfaces of the piece 132 and the second fixed contact piece 133, and the basin 119 b is in a state of being positioned at the left corner in the drawing of the basin rotation unit 129. It can be experienced that the oscilloscope 119b has been switched due to the click feeling caused by being positioned at the left corner.

  The forward / reverse switching switch of the second example is shown in FIG. 9A, and is a seesaw-type movable contact piece. In the case, the first fixed contact is in the space where the rotating portion 151 rotates. The contact portion of the piece 152 is disposed so as to be opposed to each other, and the contact portion of the second fixed contact piece 153 is faced so as to face the same in a position parallel to the first fixed contact piece 152. The first fixed contact piece 152 and the second fixed contact piece are arranged to support the first seesaw type movable contact piece 154 and the second seesaw type movable contact piece 155 so as to slide in a seesaw shape. 153. Then, the spring 158 is inserted into the rotating portion 151 and the basins 161 and 162 are mounted in opposite directions, and the plate surface of the first seesaw-type movable contact piece 154 supported by the common terminal 156. The other side 162 is in contact with the plate surface of the second seesaw-type movable contact piece 155 supported by the common terminal 157.

  In the forward / reverse switching switch having such a configuration, when the motor is driven in the forward rotation, as shown in FIG. 9A, one oscilloscope 161 is shown in the first seesaw type movable contact piece 154. The contact portion of the first seesaw-type movable contact piece 154 supported by the common terminal 156 contacts the first fixed contact piece 152 by contacting the plate surface on the left side of the position supported by the common terminal 156. It becomes a state. At the same time, the other seesaw 162 is brought into contact with the plate surface on the right side of the position of the second seesaw type movable contact piece 155 where it is supported by the common terminal 157, whereby the second seesaw supported by the common terminal 157 is contacted. The contact portion of the movable movable contact 155 comes into contact with the second fixed contact 153.

In order to switch from the normal rotation to the reverse rotation in this state, as shown in FIG. 9B, by rotating the rotating portion 151 on which the oscillating bodies 161 and 162 are mounted in the clockwise direction in the drawing, 161 slides on the surface of the first seesaw-type movable contact piece 154 and passes through the portion supported by the common terminal 156, so that the first seesaw-type movable contact piece 154 is inverted, and the first fixed contact The contact state with the piece 152 is released, and the contact portion on the opposite side comes into contact with the second fixed contact piece 153.
Similarly, the second seesaw type movable contact piece 155 is reversed by the other oscilloscope 162 sliding on the surface of the second seesaw type movable contact piece 155 and passing the portion supported by the common terminal 157. The contact state with the second fixed contact piece 153 leaves and the contact portion on the opposite side comes into contact with the first fixed contact piece 152.
In this way, the contact state is reversed, so that the connection to the motor is reversed, and the motor can be driven in the reverse rotation.

JP2002-154073

However, in the forward / reverse switching switch described in the prior art, in the so-called sliding movable contact in the forward / reverse switching switch of the first example, the contact between the movable contact and the fixed contact is between metals. Because the movable contact piece or the fixed contact piece is in direct contact with the movable contact piece or the fixed contact piece, the movable contact piece or the fixed contact piece is scraped, resulting in unstable contact and a rise in temperature of the terminal portion due to energization. It was.
Furthermore, the movable contact piece and the fixed contact piece that perform the sliding motion do not have a switching feeling, and are composed of cam parts and other parts made of resin parts, which increases the number of parts for generating the feeling. There is also a problem that.
In addition, because the structure is used to climb over the cam crest using a rocker to generate a switching feeling, the structure of the cam crest and the sliding range of the rocker are wide. There is a problem that it can be stopped and contact instability occurs.

  Also, in the so-called seesaw type movable contact piece in the forward / reverse switching switch of the second example, there is no contact between metals as in the first example. There is a problem in that an occlusion for switching the movable contact piece is necessary, and the number of parts is increased accordingly.

Accordingly, it is necessary to generate the contact pressure / switching feeling of the movable contact piece without increasing the number of parts, compared with the conventional first and second example mechanisms. The seesaw-type movable contact piece of the second example is adopted instead of the slide-type movable contact piece, and the seesaw mechanism of the spring reversal type using the coil spring is adopted instead of the seesaw type employing the oscilloscope.
In this spring-reversed seesaw mechanism, the first problem is to ensure the space distance between the different poles. With normal spring reversal, the movement of the support contact position of the movable contact piece is limited. Therefore, there is a problem that the distance between the different poles when the movable contact is tilted is short, and as a solution to that problem, the seesaw mechanism adopts a shape that takes into account the sliding motion on the support, It is necessary to use a spring reversing sea sauce ride mechanism.

  In order to solve the above problems, the forward / reverse rotation selector switch for an electric power tool of the present invention is configured as follows.

(1) The forward / reverse switching switch for an electric tool according to the present invention is:
A rotating member that is rotated by operation of the switching lever ;
A first support contact piece having a first support portion disposed in a first direction with respect to the rotation axis of the rotation member and parallel to the rotation axis;
A second support contact piece having a second support portion disposed in a second direction opposite to the first direction with respect to the rotation axis and having a second support portion parallel to the rotation axis;
A first movable contact piece that contacts the first support contact piece at the first support portion;
A second movable contact piece that contacts the second support contact piece at the second support portion;
A first spring that engages with the rotating member and biases the first movable contact piece in a direction in which the first movable contact piece is pressed against the first support portion;
A second spring that engages with the rotating member and biases the second movable contact piece in a direction in which the second movable contact piece is pressed against the second support portion;
A first first movable contact portion that contacts the first movable contact piece when the rotating member is rotated to the normal rotation position;
A first second movable contact portion that contacts the second movable contact piece when the rotating member is rotated to the reverse rotation position;
A second first movable contact portion that contacts the first movable contact piece when the rotating member is rotated to the reverse position;
A second second movable contact portion that comes into contact with the second movable contact piece when the rotating member is rotated to the forward rotation position;
A forward / reverse switching switch for an electric tool equipped with
The rotating member is
When the rotating member is rotated to an intermediate position that is intermediate between the forward rotation position and the reverse rotation position, the rotation member protrudes in a direction toward the first support portion and engages with one end of the first spring. A first spring engaging boss;
A second spring engaging boss that protrudes in a direction toward the second support portion when the rotating member rotates to the intermediate position and engages with one end of the second spring;
With
The first movable contact piece is
A first spring engaging portion that is loosely fitted to the other end of the first spring and pressed against the first support portion by the first spring;
A first first contact portion that contacts the first first movable contact portion;
A first second contact portion that contacts the second first movable contact portion;
When the rotating member rotates, the first contact position where the first spring engagement portion contacts the first support portion slides, and the first contact position serves as an axis. Oscillates in the direction of rotation opposite to the direction of rotation of the rotating member,
The second movable contact piece is
A second spring engaging portion that is loosely fitted to the other end of the second spring and pressed against the second support portion by the second spring;
A second first contact portion in contact with the first second movable contact portion;
A second second contact portion that contacts the second second movable contact portion;
When the rotating member rotates, a second contact position where the second spring engagement portion contacts the second support portion slides, and the second contact position serves as an axis. The rotating member swings in a direction opposite to the rotating direction in which the rotating member rotates.
(2) In the forward / reverse switching switch for the electric tool,
When the rotating member is rotated to the forward rotation position, the first spring is bent by the first spring engaging boss and the first spring engaging portion, so that the first contact portion is When the second spring is bent by the second spring engagement boss and the second spring engagement portion, the second contact portion is urged in a direction to press against the first movable contact portion. Urging in the direction of pressing against the second movable contact portion of No. 2,
When the rotating member is rotated to the reverse rotation position, the first spring is bent by the first spring engaging boss and the first spring engaging portion, so that the first contact portion is moved to the second position. And the second spring is bent by the second spring engagement boss and the second spring engagement portion, thereby causing the second contact portion to be urged toward the first movable contact portion. It is preferable to urge in the direction of pressing against the second movable contact portion.

The forward / reverse switching switch for an electric power tool according to the present invention slides a movable contact piece supported by a support piece in a seesaw shape, and performs a sea-source ride operation with a spring pressing force to reverse the spring to a fixed contact piece. Since the contact structure is adopted, it is possible to avoid the occurrence of scraping between the contact pieces by the slide mechanism as much as possible.
Furthermore, the sea source ride operation has a structure that uses the pressing force of the spring, so there is no need to prepare a separate feeling part and the reversing force of the spring gives a feeling similar to a click feeling. it can.
Further, since the spring is used to move the movable contact piece and the seesaw is used and the reversing force of the spring is used for switching, the switching lever cannot be stopped at the intermediate position, so that reliable switching can be performed.
Furthermore, in order to move the movable contact piece, a structure is provided in which the spring is directly attached on the movable contact piece, so that, for example, parts for moving the movable contact piece, burrs, and the like can be reduced.

  And by adopting a structure in which the sea source ride operation is performed using the reversal force of the spring with respect to the movable contact piece, a predetermined spatial distance between the different poles is ensured for the positional relationship between the fixed contact piece and the movable contact piece, For example, it can be used for a forward / reverse switching switch of an AC power tool.

1 is an overall perspective view of a forward / reverse switching switch for an electric tool according to the present invention. FIG. 4 is a perspective view of only the forward / reverse switching switch portion. It is the perspective view which decomposed | disassembled and showed the forward / reverse rotation selector switch. FIG. 4 is an exploded perspective view showing the forward / reverse selector switch from a direction different from FIG. 3. FIG. 6 is a plan view showing the operation of the switch. It is a whole perspective view of the forward / reverse rotation switch for a power tool of the first example in the prior art. It is the perspective view which decomposed | disassembled and showed the part of the forward / reverse rotation selector switch. FIG. 6 is a schematic plan view showing the operation of the switch. It is the schematic plan view which showed the operation | movement of the switch of the 2nd example in a prior art.

  An embodiment of a forward / reverse switching switch for an electric tool according to the present invention will be described with reference to the drawings.

  As shown in FIG. 1 and FIG. 2, the forward / reverse switching switch for an electric tool according to the present invention has a switch main body 11 in which a circuit for controlling a motor and the like are incorporated as a whole, and the switch main body 11. And a trigger 14 connected to the switch main body 11 with a sliding shaft interposed therebetween, and the like.

  As shown in FIGS. 3 and 4, the changeover switch portion 13 is formed of a resin and is formed in a substantially rectangular parallelepiped shape, and a changeover case 15 having a space for accommodating a part for switching the movable contact piece therein, Fitted to a rotating portion 16 formed in a cylindrical shape so as to be rotatable at a substantially central position of the switching case 15 and a first spring engaging boss 44 formed as a convex portion on the side wall surface of the rotating portion 16. A first spring 17 to be engaged, a first movable contact piece 18 which moves by engaging with the first spring 17, a second spring 19 to be fitted to the second spring engaging boss 45 on the opposite side to which the first spring 17 is engaged, The second movable contact piece 21 that moves by engaging with the second spring 19, the first fixed contact piece 22 that is accommodated on the side wall surface of the switching case 15, and the first fixed contact piece 22 are arranged at relative positions where the first fixed contact piece 22 is disposed. The second fixed contact piece 23 arranged in the same manner as the first fixed contact piece 22, the arranged first and second A first support contact piece 24 that is a common terminal disposed at a position orthogonal to the fixed contact pieces 22 and 23; a second support contact piece 25 that is a common terminal disposed at a position opposite to the first support contact piece 24; A cover for closing the upper space of the switching case 15 (not shown) is generally configured.

  The switching case 15 includes first and second support contact piece storage portions 27 and 28 for storing the first and second support contact pieces 24 and 25 formed of conductive members at both ends in the longitudinal direction formed in a rectangular parallelepiped shape. And first and second fixed contact receiving portions 31 and 32 for storing first and second fixed contact pieces 22 and 23 formed of conductive members at both ends in the short direction. (2) A rotating storage portion 33 for rotatably mounting the rotating portion 16 at a central position surrounded by the support contact piece storage portions 27, 28 and the first and second fixed contact piece storage portions 31, 32 is provided. It is configured.

  The rotation storage part 33 is provided with a rotation groove 35 large enough to accommodate the lower rotation plate part 43 of the rotation part 16, and a guide groove for guiding the rotation boss 47 by inserting it into the longitudinal direction side of the switching case 15. 36 is provided, and a rotation support shaft 34 that is a convex portion with which the rotation center concave portion 46 of the rotation portion 16 engages is provided at the center position.

  The rotating part 16 is provided with a disk-shaped upper rotating plate part 42 and lower rotating plate part 43 above and below the rectangular parallelepiped support part 41, and the first spring 17 is fitted to the side wall surface of the support part 41. A first spring engagement boss 44 is provided, and a second spring engagement boss 45 that is fitted to the second spring 19 is provided on the support portion 41 on the opposite side of the first spring engagement boss 44. At the center position, a rotation center recess 46 that engages with the rotation support shaft 34 provided in the rotation storage portion 33 of the switching case 15 is provided, and is an eccentric position of the lower rotation plate portion 43 and is spring-engaged. The rotating boss 47 is formed on the boss side so as to protrude downward.

  The first and second spring engaging bosses 44 and 45 are fitted so as to be inserted into one end portions of the first and second springs 17 and 19, and prevent the spring from buckling when rotating. To do.

  The first movable contact piece 18 is formed of a metal conductive member, is formed in a substantially U-shape, and the first spring engagement member is formed in a size that allows the first spring 17 to be loosely fitted in the lateral direction. The second contact portion 53 that extends in the direction perpendicular to the first portion 51 and the first spring engagement portion 51 and bends away from the first spring engagement portion 51 to contact the second fixed contact piece 23. A first contact portion 52 that extends in a perpendicular direction and bends in a direction away from the first fixed contact piece 22 and contacts the first fixed contact piece 22, and the opposite side surface of the first spring engagement portion 51 is the sea support ride support portion of the first support contact piece 24. It has a structure including a sea sauce ride portion 48 that slides in contact with 65 and serves as a fulcrum.

  The second movable contact piece 21 is formed in the same shape as the first movable contact piece 18, is formed in a substantially U-shape with a metal conductive member, and the second spring 19 can be loosely fitted in the lateral direction. A second spring engaging portion 54 formed in a size, a first contact portion 55 extending in a direction perpendicular to the second spring engaging portion 54 and bent away from the second spring engaging portion 54 to contact the first fixed contact piece 22, the opposite side The second spring engaging portion 54 is provided with a second contact portion 56 that extends in a direction perpendicular to the second spring engaging portion 54 and bends away from the second spring engaging portion 54 to come into contact with the second fixed contact piece 23. The structure includes a sea sauce ride portion 49 that slides in contact with the sea sauce ride support portion 67 of the two support contact pieces 25 and serves as a fulcrum.

  The first fixed contact piece 22 is formed of a metal conductive member, is formed in a substantially T-shape, and the upper position is a terminal connection portion 57 that engages with the connection piece 50 and connects to an external terminal. Yes, the upper and lower left and right upper ends of the elongated flat plate are bent inward so as to form a C shape, and the first contact portion 52 of the first movable contact piece 18 or the second of the second movable contact piece 21 The first movable contact portion 58 and the second movable contact portion 59 that are in contact with the first contact portion 55 are provided.

  The second fixed contact piece 23 is formed in the same shape as the first fixed contact piece 22 and is formed in a substantially T shape, and the upper position engages with the connection piece 50 to connect to an external terminal. The second contact portion 53 of the first movable contact piece 18 or the second movable contact piece is formed by bending the left and right upper end portions of the elongated flat plate shape at the lower position so as to form a C shape inward. The first movable contact portion 62 and the second movable contact portion 63 that are in contact with the 21 second contact portion 56 are provided.

  The first support contact piece 24 is a so-called common terminal that is slidable while being in contact with the seesaw ride portion 48 that is the back surface of the first movable contact piece 18 and serves as a fulcrum of the seesaw. A flat plate member made of a member is bent at a right angle, the base side is engaged with the connection piece 50 to form a terminal contact portion 64 to be connected to an external terminal, and one side edge is cut into a U shape on the side bent at a right angle. The first movable contact piece 18 is sandwiched and slid and the sea sauce ride support part 65 is provided.

  The second support contact piece 25 is formed in the same shape as the first support contact piece 24, is slid while being in contact with the sea sauce ride portion 49, which is the back surface of the second movable contact piece 21, and serves as a fulcrum for the seesaw. A so-called common terminal, a flat plate member made of a metal conductive member is bent at a right angle, and a base contact portion 66 is engaged with the connection piece 50 to form a terminal contact portion 66 connected to an external terminal, and is bent at a right angle. It has a structure including a sea sauce ride support portion 67 for sandwiching and sliding the second movable contact piece 21 formed by cutting out one side edge portion in a U-shape on the side.

In order to accommodate each of these components in the switching case 15, first, the first support contact piece 24, which is a common terminal, is set in a state where the sea-source ride support portion 65 faces the rotation storage portion 33 through a gap. The first support contact piece storage portion 27 is mounted. Similarly, the second support contact piece 25 is mounted on the second support contact piece storage portion 28 with the sea-source ride support portion 67 facing the rotation storage portion 33 through a gap. To do.
Similarly, the first fixed contact piece 22 is connected to the first movable contact portion 58 and the second movable contact portion through two through windows provided in the first fixed contact piece storage portion 31 provided on one side wall surface of the switching case 15. The contact portion 58, 59 is attached to the rotation storage portion 33 side through the portion 59.
Similar to the first fixed contact piece 22, the second fixed contact piece 23 has a first movable contact with two through windows provided in the second fixed contact piece storage portion 32 provided on the other side wall surface of the switching case 15. The portion 62 and the second movable contact portion 63 are penetrated, and the contact portions 62 and 63 are mounted facing the rotating storage portion 33 side.

  Next, the first spring 17 is engaged with the first spring engaging boss 44 of the rotating portion 16, the second spring 19 is engaged with the second spring engaging boss 45, and the first spring 17 is engaged with the tip of the first spring 17. The first spring contact portion 51 of the first movable contact piece 18 is attached, the second spring engagement portion 54 of the second movable contact piece 21 is attached to the tip of the second spring 19, and the first movable contact piece is attached. The seesaw source portions 48 and 49 on the opposite sides of the first spring engaging portion 51 and the second spring engaging portion 54 of the 18 and the second movable contact piece 21 are used as the seesaw of the first support contact piece 24 and the second support contact piece 25. Engage with the slide support parts 65 and 67, engage the rotation center recess 46 of the rotation part 16 itself with the rotation support shaft 34, engage the rotation boss 47 with the guide groove 36, and rotate the storage part. 33.

  As shown in FIG. 5A, the change-over switch unit assembled in this way shows the state of the movable contact piece when the motor rotates in the positive direction. The second movable contact piece 21 is urged outward by the second spring 19 and the first contact portion 55 is in contact with the first movable contact portion 59 of the first fixed contact piece 22. In this state, since a stress is applied to return the bent and bent state of the second spring 19, the contact portion comes into contact in a very stable state. On the contrary, the first movable contact piece 18 is similarly urged outward by the first spring 17 with respect to the first movable contact piece 18, and the second contact portion 53 is the second fixed contact piece 23. The second movable contact portion 63 is in contact with the second movable contact portion 63. In this state, since the first spring 17 is stressed to return the bent and bent state, the contact portion is in a very stable state. Can take.

In this state, in order to reverse the motor by operating a switching lever (not shown), the first contact portion 55 of the second movable contact piece 21 is operated by operating the switching lever as shown in FIG. Is away from the first movable contact portion 58 of the first fixed contact piece 22, but the direction of pressing the second movable contact piece 21 of the second spring 19 is still pressed in a slightly bent state. The state where the sea sauce ride portion 49 of the second movable contact piece 21 is in contact with the sea sauce ride support portion 67 of the second support contact piece 25 is maintained. Similarly, the second contact portion 53 of the first movable contact piece 18 is separated from the second movable contact portion 63 of the second fixed contact piece 23, but the direction in which the first movable contact piece 18 of the first spring 17 is still pressed is still. Pressing is performed in a slightly bent state, and the state in which the sea sauce ride portion 48 of the first movable contact piece 18 is in contact with the sea sauce ride support portion 65 of the first support contact piece 24 is maintained.
The first and second spring engaging bosses 44 and 45 of the rotating portion 16 are in contact with the first and second springs 17 and 19, and the first and second movable contact pieces 18 and 21 are engaged with the first and second springs. In order to come into contact with the inner walls of the joint portions 51 and 54, the sliding operation is forcibly separated.

  Next, as shown in FIG. 5C, by further operating the switching lever, the turning portion 16 is turned, the bending of the first and second springs 17 and 19 is lost, and the sea sauce ride portion 48 is turned on. , 49 slides on the sea sauce ride support portions 65, 67 and is supported near the center position of the sea sauce ride portions 48, 49. Since this state is an extremely unstable state, an attempt is made to go in the rotational direction without maintaining this state.

Next, as shown in FIG. 5D, by further turning the switching lever, the turning portion 16 is turned, and the sea sauce ride portion 49 of the second movable contact piece 21 is turned into the sea sauce ride support portion 67. The second movable contact piece 21 itself moves in a seesaw shape and is slid to the end of the sea sauce ride portion 49.
Similarly, the sea sauce ride portion 48 of the first movable contact piece 18 is slid to the sea sauce ride support portion 65 so that the first movable contact piece 18 itself moves in a seesaw shape and slides to the end of the sea sauce ride portion 48.

  Then, as shown in FIG. 5 (E), the second movable contact piece 21 sliding to the end portion of the sea sauce ride portion 49 is moved in the direction of rotation of the second spring 19 with the end portion as a fulcrum. Due to this stress, the second contact portion 56 of the second movable contact piece 21 contacts and contacts the second movable contact portion 62 of the second fixed contact piece 23. At this time, the stress due to the bending of the distal end portion of the second spring 19 is applied in the direction of the second movable contact portion 62 (C direction in the figure), and the urging force of the second spring 19 supports the second movable contact piece 21 as the second support. Since it is applied in the direction of the contact piece 25 (D direction in the figure), it comes into contact with the sea sauce ride support portion 67 of the second support contact piece 25 in a state where the pressure of the sea sauce ride portion 49 is applied.

  Similarly, the first movable contact piece 18 that slides to the end portion of the sea sauce ride portion 48 is moved by the stress in the rotation direction of the first spring 17 with the end portion as a fulcrum. The first contact portion 52 contacts and contacts the second movable contact portion 58 of the first fixed contact piece 22. At this time, the stress due to the bending of the tip portion of the first spring 17 is applied in the direction of the second movable contact portion 58 (E direction in the figure), and the urging force of the first spring 17 supports the first movable contact piece 18 as the first support. Since it is applied in the contact piece 24 direction (F direction in the figure), it comes into contact with the sea sauce ride support portion 65 of the first support contact piece 24 in a state where the pressure of the sea sauce ride portion 48 is applied.

  Provided is a contact mechanism that employs a spring-reversed seesaw mechanism and that secures the distance between contact points by sliding a movable contact piece on a support.

DESCRIPTION OF SYMBOLS 11 Switch main-body part 12 Switching lever 13 Switching switch part 14 Trigger 15 Switching case 16 Turning part 17 1st spring 18 1st movable contact piece 19 2nd spring 21 2nd movable contact piece 22 1st fixed contact piece 23 2nd fixation Contact piece 24 First support contact piece 25 Second support contact piece 27 First support contact piece storage portion 28 Second support contact piece storage portion 31 First fixed contact piece storage portion 32 Second fixed contact piece storage portion 33 Rotation storage Part 34 rotation support shaft 35 rotation groove 36 guide groove 41 support part 42 upper rotation plate part 43 lower rotation plate part 44 first spring engagement boss 45 second spring engagement boss 46 rotation center recess 47 rotation Boss 48 Sea source ride part 49 Sea source ride part 50 Connection piece 51 First spring engagement part 52 First contact part 53 Second contact part 54 Second spring engagement part 55 First contact part 56 Second contact part 57 Terminal connection part 58 1st movable contact part 59 1st Movable contact portion 61 terminal connecting portion 62 first movable contact portion 63 second movable contact portion 64 contact portion 65 seesaw slide support portion 66 contact portion 67 seesaw slide support portion

Claims (2)

A rotating member that is rotated by operation of the switching lever ;
A first support contact piece having a first support portion disposed in a first direction with respect to the rotation axis of the rotation member and parallel to the rotation axis;
A second support contact piece having a second support portion disposed in a second direction opposite to the first direction with respect to the rotation axis and having a second support portion parallel to the rotation axis;
A first movable contact piece that contacts the first support contact piece at the first support portion;
A second movable contact piece that contacts the second support contact piece at the second support portion;
A first spring that engages with the rotating member and biases the first movable contact piece in a direction in which the first movable contact piece is pressed against the first support portion;
A second spring that engages with the rotating member and biases the second movable contact piece in a direction in which the second movable contact piece is pressed against the second support portion;
A first first movable contact portion that contacts the first movable contact piece when the rotating member is rotated to the normal rotation position;
A first second movable contact portion that contacts the second movable contact piece when the rotating member is rotated to the reverse rotation position;
A second first movable contact portion that contacts the first movable contact piece when the rotating member is rotated to the reverse position;
A second second movable contact portion that comes into contact with the second movable contact piece when the rotating member is rotated to the forward rotation position;
A forward / reverse switching switch for an electric tool equipped with
The rotating member is
When the rotating member is rotated to an intermediate position that is intermediate between the forward rotation position and the reverse rotation position, the rotation member protrudes in a direction toward the first support portion and engages with one end of the first spring. A first spring engaging boss;
A second spring engaging boss that protrudes in a direction toward the second support portion when the rotating member rotates to the intermediate position and engages with one end of the second spring;
With
The first movable contact piece is
A first spring engaging portion that is loosely fitted to the other end of the first spring and pressed against the first support portion by the first spring;
A first first contact portion that contacts the first first movable contact portion;
A first second contact portion that contacts the second first movable contact portion;
When the rotating member rotates, the first contact position where the first spring engagement portion contacts the first support portion slides, and the first contact position serves as an axis. Oscillates in the direction of rotation opposite to the direction of rotation of the rotating member,
The second movable contact piece is
A second spring engaging portion that is loosely fitted to the other end of the second spring and pressed against the second support portion by the second spring;
A second first contact portion in contact with the first second movable contact portion;
A second second contact portion that contacts the second second movable contact portion;
When the rotating member rotates, a second contact position where the second spring engagement portion contacts the second support portion slides, and the second contact position serves as an axis. Oscillates in a rotation direction opposite to the rotation direction in which the rotation member rotates,
A forward / reverse changeover switch for electric tools. When the rotating member is rotated to the forward rotation position, the first spring is bent by the first spring engaging boss and the first spring engaging portion, so that the first contact portion is When the second spring is bent by the second spring engagement boss and the second spring engagement portion, the second contact portion is urged in a direction to press against the first movable contact portion. Urging in the direction of pressing against the second movable contact portion of
When the rotating member is rotated to the reverse rotation position, the first spring is bent by the first spring engaging boss and the first spring engaging portion, so that the first contact portion is moved to the second position. And the second spring is bent by the second spring engagement boss and the second spring engagement portion, thereby causing the second contact portion to be urged toward the first movable contact portion. Urging in the direction of pressing against the second movable contact portion of
The forward / reverse switching switch for an electric tool according to claim 1.

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