JP7087789B2 - Driving machine - Google Patents

Description

The present disclosure relates to a driving machine provided with an urging member and a striking portion.

Patent Document 1 describes an electric driving machine for driving nails. The driving machine described in Patent Document 1 is provided with a mechanism for driving a nail by moving a blade by compressing a coil spring by a rotational force of a motor and releasing the compressed coil spring.

Japanese Unexamined Patent Publication No. 2010-125578

In a driving machine that drives an object such as a nail or staple by transmitting the energy stored in the urging member such as a spring to the striking part, the urging member that stores the driving energy is longer than the length of the object to be driven. Stroke or energy to hit the object firmly is required. For example, as a coil spring for a driving machine, a coil spring having a long length in the expansion / contraction direction is used, and the aspect ratio tends to be large. Therefore, the behavior of the coil spring tends to be unstable during the driving operation. In this case, after the object is driven, the coil spring or its receiving member may be damaged by the vibration at both ends of the coil spring.

An object of the present disclosure is to provide a technique for improving the durability of an urging member that stores driving energy.

The driving machine of one embodiment has a motor, a housing in which the motor is housed, a driver blade for driving a fastener, a striking portion including a plunger to which the driver blade is attached, and a striking portion on the plunger side of the striking portion. A first end portion and a second end portion on the opposite side of the first end portion are provided, and an urging member driven by the rotational force of the motor and a urging member provided on the first end portion side of the urging member. It has a first support portion to be mounted and a second support portion arranged on the second end portion side of the urging member. The plunger is arranged between the first support portion and the urging member, and the second end portion of the urging member is located between the second support portion and the second end portion of the urging member. The first elastic member and the second elastic member are arranged in order from the two end side.

The driving machine of another embodiment includes a striking portion including a motor, a housing in which the motor is housed, a driver blade for driving the fastener, and a plunger to which the driver blade is attached, and the plunger of the striking portion. A urging member having a first end portion on the side and a second end portion on the opposite side of the first end portion and driven by the rotational force of the motor, and the second end portion side of the urging member. A counterweight that is driven in a direction opposite to the moving direction of the plunger by the rotational force of the motor to suppress the reaction when hitting the fastener, and the first end portion of the urging member. It has a first support portion provided on the side and a second support portion arranged on the second end portion side of the urging member. The plunger is arranged between the first support portion and the urging member, and the counterweight is arranged between the second support portion and the urging member, and the counterweight and the urging member are arranged. The first elastic member and the second elastic member are arranged in order from the second end portion side of the urging member with the second end portion of the member.

In the driving machine of one embodiment, the durability of the urging member can be improved.

It is a side sectional view which shows one Embodiment of a driving machine. It is a perspective view of the hitting part, the counter weight and the drive mechanism part of the driving machine of FIG. It is a side sectional view around the coil spring of the driving machine of FIG. It is a side view of the hitting part, the weight and the drive mechanism provided in the driving machine of FIG. It is a block diagram which shows the control system of a driving machine. FIG. 3 is a plan view of two elastic members between the counterweight and the coil spring shown in FIG. 3 as viewed from the second end side of the coil spring. It is an enlarged view around the counterweight shown in FIG. It is an enlarged view around the plunger of the driving machine which is a modification with respect to FIG. It is a side sectional view around the coil spring of the driving machine which is another modification with respect to FIG. It is a side sectional view around the coil spring of the driving machine which is another modification with respect to FIG. It is an enlarged view around the counterweight shown in FIG. It is an enlarged view around the plunger of the driving machine which is a modification with respect to FIG.

Hereinafter, embodiments of the driving machine will be described with reference to the drawings.

The driving machine 10 shown in FIG. 1 includes a housing 11, a striking portion 12, a magazine 13, an electric motor 14, a conversion mechanism 15, a control board 16, a battery pack 17, and a counterweight 18. The striking portion 12 is provided in the housing 11. The electric motor 14 is provided in the housing 11, and the conversion mechanism 15 is provided in the housing 11. The control board 16 is provided in the housing 11. The counterweight 18 is provided in the housing 11.

Further, each of the magazine 13 and the battery pack 17 is attached to the housing 11. The battery pack 17 can be attached to and detached from the housing 11.

The housing 11 is made of metal and synthetic resin, and the housing 11 has a tubular main body portion 19, a handle 20 connected to the main body portion 19, and a motor case 21 connected to the main body portion 19. .. The mounting portion 22 is connected to the handle 20 and the motor case 21. The injection portion 23 is provided outside the main body portion 19, and the injection portion 23 is fixed to the main body portion 19. The injection unit 23 has an injection path 24. The injection path 24 is a passage that guides the fastener 25. The user can grasp the handle 20 by hand and press the tip of the injection portion 23 against the driven material W1.

The magazine 13 is supported by the housing 11 and the ejection portion 23. The motor case 21 is arranged between the handle 20 and the magazine 13 in the direction of the axis A1. The magazine 13 accommodates a plurality of fasteners 25. The fastener 25 includes nails, and the material of the fastener 25 includes metal, non-ferrous metal, and steel. The plurality of fasteners 25 are connected to each other by connecting elements. The connecting element may be a wire, an adhesive, or a resin. The fastener 25 has a rod shape. The magazine 13 has a feeder. The feeder sends the fastener 25 housed in the magazine 13 to the injection path 24.

The hitting portion 12 is provided both inside and outside the main body portion 19. The striking portion 12 has a plunger 40 arranged in the main body portion 19 and a driver blade 41 fixed to the plunger 40. The plunger 40 is made of metal or synthetic resin. The driver blade 41 is made of metal.

In the driving machine 10, the urging member that applies the energy for the batter 12 to drive the fastener 25 to the batter 12 is the coil spring 35. The coil spring 35 is housed in a frame inside the main body 19. The frame includes a top holder (second support portion) 31, a bottom holder (first support portion) 32 on the opposite side of the top holder 31, and a plurality of guide bars 33 fixed to the top holder 31 and the bottom holder 32. (See FIG. 2). Further, the guide shaft 34 is fixed to the top holder 31 and the bottom holder 32.

In FIG. 1, the top holder 31 and the bottom holder 32 are members different from the housing 11. However, as a modification, a part of the housing 11 may be used as the top holder 31 or the bottom holder 32. In other words, a part of the housing 11 may be a first support portion or a second support portion.

The guide shaft 34 is provided in the main body portion 19. The axis A1 passes through the center of the guide shaft 34. The material of the guide shaft 34 may be metal, non-ferrous metal, or steel. The material of the top holder 31 and the bottom holder 32 may be metal, non-ferrous metal, or steel. In the example shown in FIG. 2, two guide bars 33 are fixed to the top holder 31 and the bottom holder 32. The two guide bars 33 are arranged so as to face each other. Each of the two guide bars 33 has a plate shape and is arranged in parallel with the axis A1.

The plunger 40 is attached so as to surround the outer peripheral surface of the guide shaft 34. The plunger 40 can be moved along the guide shaft 34 in the direction of the axis A1 shown in FIG. 1 in a part of the space between the top holder 31 and the bottom holder 32. The guide shaft 34 defines the position of the plunger 40 in the radial direction of the circle about the axis A1. The guide bar 33 defines the position of the plunger 40 in the circumferential direction of the circle about the axis A1. The driver blade 41 can operate in parallel with the axis A1 together with the plunger 40. The driver blade 41 is operable in the injection path 24.

The counterweight 18 suppresses the recoil received by the housing 11 when the fastener 25 is driven. The material of the counterweight 18 may be metal, non-ferrous metal, steel, or ceramic. The counterweight 18 is attached to the guide shaft 34. The counterweight 18 has a tubular shape as an example, and the pin 18P and the weight arm portion 18A are provided on the counterweight 18. The counterweight 18 can move in the axis A1 direction along the guide shaft 34. The guide shaft 34 defines the position of the counterweight 18 in the radial direction of the circle about the axis A1. The guide bar 33 defines the position of the counterweight 18 in the circumferential direction of the circle about the axis A1.

A coil spring 35 is arranged in a frame including a top holder 31, a bottom holder 32, and a plurality of guide bars 33 shown in FIG. 1. The coil spring 35 is arranged between the plunger 40 and the counterweight 18 in the direction of the axis A1. As the coil spring 35, a metal compression coil spring can be used as an example. The coil spring 35 includes a first end portion on the plunger 40 side in the axis A1 direction and a second end portion on the opposite side of the first end portion. The coil spring 35 can be expanded and contracted in the axis A1 direction. The rotational force of the electric motor 14 is transmitted as a compressive force to the coil spring 35 via the speed reducer 63, the conversion mechanism 15, the plunger 40, and the counterweight 18. The coil spring 35 receives a compressive force in the direction of the axis A1 and stores elastic energy. The coil spring 35 is an example of an urging member that urges the striking portion 12 and the counterweight 18. The other urging member may be an air spring or the like. Further, the material of the coil spring 35 may be plastic, and the cross section may be circular or elliptical.

As shown in FIG. 3, the plunger 40 is arranged between the bottom holder 32 of the frame and the coil spring 35 in the axis A1 direction. A plunger bumper 32B is arranged between the plunger 40 and the bottom holder 32. Further, the counterweight 18 is arranged between the top holder 31 of the frame and the coil spring 35 in the direction of the axis A1. A weight bumper 31B is arranged between the counterweight 18 and the top holder 31. Each of the weight bumper 31B and the plunger bumper 32B is an elastic member made of, for example, synthetic rubber.

Each of the plunger 40 and the counterweight 18 moves along the axis A1. When the energy stored in the coil spring 35 is released, the plunger 40 moves (descends) in the D1 direction of FIG. Further, when the energy stored in the coil spring 35 is released, the counterweight 18 moves (rises) in the D2 direction of FIG.

The plunger bumper 32B prevents the plunger 40 from colliding with the bottom holder 32. Further, the impact force caused by the plunger 40 colliding with the plunger bumper 32B is alleviated by the elastic deformation of the plunger bumper 32B. By arranging the plunger bumper 32B between the plunger 40 and the bottom holder 32, damage to the plunger 40 and the bottom holder 32 can be suppressed.

Further, the weight bumper 31B prevents the counterweight 18 from colliding with the top holder 31. The impact force caused by the counterweight 18 colliding with the weight bumper 31B is alleviated by the elastic deformation of the weight bumper 31B. By providing the weight bumper 31B between the top holder 18 and the counterweight 18, damage to the counterweight 18 and the top holder 31 can be suppressed.

Further, an elastic member different from the weight bumper 31B is arranged between the coil spring 35 and the top holder 31. An elastic member 36 and an elastic member 37 are interposed between the top holder 31 of the frame and the second end portion of the coil spring 35 in order from the second end portion side of the coil spring 35.

In the example shown in FIG. 3, a counterweight 18 is interposed between the top holder 31 of the frame and the second end of the coil spring 35. An elastic member 36 and an elastic member 37 are interposed between the counterweight 18 and the second end portion of the coil spring 35 in this order from the second end portion side of the coil spring 35.

Further, in the example shown in FIG. 3, an elastic member 38 is interposed between the plunger 40 and the first end portion of the coil spring 35. The materials, structures, and functions of the elastic members 36, 37, and 38 will be described later.

The battery pack 17 shown in FIG. 1 can be attached to and detached from the mounting portion 22. The battery pack 17 has a storage case 17C and a plurality of battery cells housed in the storage case 17C. The battery cell is a secondary battery that can be charged and discharged, and any of a lithium ion battery, a nickel hydrogen battery, a lithium ion polymer battery, and a nickel cadmium battery can be used as the battery cell. The battery pack 17 is a DC power source, and the electric power of the battery pack 17 can be supplied to the electric motor 14.

The control board 16 shown in FIG. 1 is provided in the mounting portion 22, and the controller 45 and the inverter circuit 46 shown in FIG. 6 are provided in the control board 16. The controller 45 is a microcomputer having an input port, an output port, an arithmetic processing unit, and a storage unit. The inverter circuit 46 has a plurality of switching elements, and the plurality of switching elements can be turned on and off, respectively. The controller 45 outputs a signal for controlling the inverter circuit 46. An electric circuit is formed between the battery pack 17 and the electric motor 14. The inverter circuit 46 is a part of an electric circuit and connects and disconnects the electric circuit.

As shown in FIG. 1, a trigger 47 and a trigger switch 48 are provided on the handle 20, and the trigger switch 48 is turned on when the user applies an operating force to the trigger 47. When the user releases the operating force applied to the trigger 47, the trigger switch 48 is turned off. The position detection sensor 49 shown in FIG. 5 is provided in the housing 11. The position detection sensor 49 estimates the positions of the plunger 40 and the counterweight 18 in the axis A1 direction based on the rotation angle of the electric motor 14, for example, and outputs a signal. The controller 45 receives the signal of the trigger switch 48 and the signal of the position detection sensor 49, and outputs a signal for controlling the inverter circuit 46.

The electric motor 14 has a rotor 60 and a stator 61, and a motor shaft 62 is attached to the rotor 60. In the electric motor 14, the motor shaft 62 rotates when electric power is supplied from the battery pack 17. The speed reducer 63 is arranged in the motor case 21. The speed reducer 63 has a plurality of sets of planetary gear mechanisms, input elements and output elements. The input element is connected to the motor shaft 62. The electric motor 14 and the speed reducer 63 are arranged concentrically with the axis B1 as the center.

The conversion mechanism 15 converts the rotational force of the output element of the speed reducer 63 into the operating force of the striking portion 12 and the operating force of the counterweight 18. As shown in FIG. 2, the conversion mechanism 15 has a first gear 50, a second gear 51, and a third gear 52. The material of the first gear 50, the second gear 51, and the third gear 52 may be metal, non-ferrous metal, or steel. Each of the first gear 50, the second gear 51, and the third gear 52 is rotatably supported via a holder that supports the output element of the speed reducer 63 (see FIG. 1). The first gear 50 is rotatable about the axis B1 of FIG. Further, each of the second gear 51 and the third gear 52 can rotate about an axis parallel to the axis B1 of FIG. The outer diameter of the first gear 50, the outer diameter of the second gear 51, and the outer diameter of the third gear 52 are the same. The second gear 51 meshes with the first gear 50 and the third gear 52.

Further, as shown in FIG. 2, the latch 55 is attached to the guide bar 33. The latch 55 is rotatable about the support shaft 56 with respect to the guide bar 33. The latch 55 has an arm 57 and a hook 58. The arm 57 and the hook 58 are arranged so as to be spaced apart from the support shaft 56 in the longitudinal direction of the latch 55. The hook 58 can contact and separate from the pin 18P of the counterweight 18. Specifically, the hook 58 can be engaged and disengaged from the pin 18P.

<Operation of the driving machine>
Next, the operation of the driving machine 10 will be described. In the case of the driving machine 10 shown in FIG. 1, the rotational force of the electric motor 14 is transmitted to the coil spring 35, which is an urging member, via the speed reducer 63 and the conversion mechanism 15, and the coil spring 35 is generated by the rotational force of the electric motor 14. Driven.

When the controller 45 (see FIG. 5) detects that the trigger switch 48 is off, power is not supplied to the electric motor 14, and the motor shaft 62 is stopped. When the electric motor 14 is stopped, as shown in FIG. 3, the plunger 40 is stopped at a position in contact with the plunger bumper 32B, that is, at bottom dead center. Further, the counter weight 18 is urged by the elastic force of the coil spring 35, and is stopped at a position in contact with the weight bumper 31B, that is, at the top dead center.

When the user presses the tip of the injection unit 23 against the driven material W1 and the controller 45 detects that the trigger switch 48 is turned on, the controller 45 supplies electric power to the electric motor 14. When the electric power of the battery pack 17 is supplied to the electric motor 14 and the motor shaft 62 rotates in the forward direction, the rotational force of the motor shaft 62 is transmitted to the first gear 50 (see FIG. 2) via the speed reducer 63. In FIG. 2, when the first gear 50 rotates counterclockwise, the second gear 51 (see FIG. 2) rotates clockwise, and the third gear 52 (see FIG. 2) rotates counterclockwise.

When the first gear 50 shown in FIG. 4 rotates counterclockwise and the cam roller 50C of the first gear 50 engages with the first arm portion 40A of the plunger 40, the plunger 40 resists the urging force of the coil spring 35. It moves (ascends) in the second direction D2 shown in FIG.

Further, when the third gear 52 shown in FIG. 4 rotates counterclockwise and the cam roller 52C of the third gear 52 engages with the weight arm portion 18A of the counterweight 18, the counterweight 18 moves in the first direction D1 (in addition, the counterweight 18 moves in the first direction D1. Descent).

Further, when the cam roller 50C is engaged with the first arm portion 40A during the rotation of the first gear 50 and the second gear 51, one cam roller 51C is engaged with the second arm portion A2 of the plunger 40. .. After that, the cam roller 50C is released from the first arm portion 40A. Further, when one cam roller 51C is engaged with the second arm portion 40A2, the other cam roller 51C is engaged with the second arm portion 40A2. Next, the cam roller 51C previously engaged with the second arm portion 40A2 is released from the second arm portion 40A2.

Further, when the counterweight 18 further moves in the second direction D2 and the pin 18P and the latch 55 come into contact with each other, the latch 55 operates counterclockwise (rotates around the support shaft 56). Further, when the plunger 40 moves in the first direction D1 and the contact portion 40C of the plunger 40 comes into contact with the arm 57 of the latch 55, the latch 55 further operates counterclockwise (rotates around the support shaft 56). The hook 58 engages the pin 18P.

The third gear 52 further rotates, and the cam roller 52C is released from the weight arm portion 18A. At this time, since the contact portion 40C of the plunger 40 is in contact with the arm 57, the latch 55 is stopped.

When the plunger 40 further rises and reaches top dead center, both of the two cam rollers 51C are released from the second arm portion 40A2, and the plunger 40 is lowered by the urging force of the coil spring 35. Even if the plunger 40 starts descending, if the contact portion 40C is in contact with the arm 57, the latch 55 is stopped. Therefore, the hook 58 is held in a state of being engaged with the pin 18P, and the counterweight 18 is stopped.

When the plunger 40 is further lowered and the contact portion 40C is separated from the arm 57, the latch 55 is operated clockwise by a spring (not shown). Then, the hook 58 is released from the pin 18P, and the counterweight 18 starts to rise by the urging force of the coil spring 35.
By adjusting the length of the arm 57, the timing at which the counterweight 18 starts to move can be adjusted.

When the plunger 40 is lowered, that is, the hitting portion 12 is lowered, the driver blade 41 shown in FIG. 1 hits the fastener 25 located in the injection path 24. The fastener 25 is driven into the material to be driven W1. After the driver blade 41 hits the fastener 25, the plunger 40 collides with the plunger bumper 32B as shown in FIG. The plunger bumper 32B absorbs a part of the kinetic energy of the striking portion 12. Further, the counterweight 18 collides with the weight bumper 31B. The weight bumper 31B absorbs a part of the kinetic energy of the weight.

When the striking portion 12 operates in the first direction D1 shown in FIG. 3 to strike the fastener 25, the counterweight 18 operates in the second direction D2 opposite to the first direction D1. Therefore, it is possible to reduce the recoil when the striking portion 12 strikes the fastener 25. When the relationship between the first timing at which the plunger 40 starts operating from the top dead center to the bottom dead center and the second timing at which the counterweight 18 starts operating from the bottom dead center to the top dead center is stabilized. , It becomes easy to reduce the recoil.

<About surging phenomenon>
By the way, when the energy of the coil spring 35 becomes large, the speed of the end portion of the coil spring 35 when the striking portion 12 shown in FIG. 1 strikes the fastener 25 becomes high, so that the end portion of the coil spring 35 due to the reaction at the time of striking. Behavior becomes unstable. Therefore, after the striking portion 12 strikes the fastener 25, the end portion of the coil spring 35 separates from the elastic member 36, and then collides with the elastic member 36, which causes a repeated surging phenomenon. The impact force at the time of collision due to this surging phenomenon increases in proportion to the impact force that strikes the fastener 25.

When the coil spring 35 and the counterweight 18 directly collide with each other due to this surging phenomenon, the coil spring 35 is damaged. Further, the coil spring 35 repeatedly collides with the counterweight 18, so that the characteristics of the coil spring 35 are likely to deteriorate. In this case, the life of the coil spring 35 as the urging member is shortened.

Therefore, in order to prevent the coil spring 35 and the counterweight 18 from directly colliding with each other, it is examined to interpose another member between the coil spring 35 and the counterweight 18. First, in order to suppress damage to the coil spring 35 due to the surging phenomenon, it is preferable to interpose a member that alleviates the impact force when the coil spring 35 collides with the coil spring 35.

From the viewpoint of improving the impact force mitigation characteristic, the member arranged between the coil spring 35 and the counterweight 18 is preferably made of a soft and easily elastically deformed material such as the weight bumper 31B. In the example shown in FIG. 3, the elastic member 37 is made of a material softer than the constituent material of the coil spring 35. The elastic member 37 is, for example, rubber such as butyl rubber, nitrile rubber, or chloroprene rubber.

If a member having excellent relaxation characteristics, such as the elastic member 37, is arranged between the coil spring 35 and the counterweight 18, damage to the coil spring 35 can be suppressed. However, when the coil spring 35 and the elastic member 37 come into direct contact with each other, the elastic member 37 is damaged by the surging phenomenon, and the relaxation characteristics are deteriorated.

Therefore, in the example shown in FIG. 3, the elastic member 36 is arranged between the elastic member 37 and the second end portion of the coil spring 35. The elastic member 36 is in contact with the second end of the coil spring 35. Further, the elastic member 37 is in contact with the elastic member 36 and the counterweight 18 and is separated from the coil spring 35. In this case, since the elastic member 37 does not come into contact with the coil spring 35, damage to the elastic member 37 due to the surging phenomenon can be suppressed.

Since the elastic member 36 comes into contact with the coil spring 35, it is required to have higher impact resistance than the elastic member 37. Further, since the elastic member 37 is arranged between the elastic member 36 and the counterweight 18, the elastic member 36 itself is not required to have a high impact mitigation characteristic, and has a characteristic of transmitting an impact to the elastic member 37. All you need is. However, a surging phenomenon occurs between the coil spring 35 and the elastic member 36. Therefore, the elastic member 36 needs to have enough elasticity to suppress damage to the coil spring 35.

The elastic member 36 is made of a material different from that of the elastic member 37. The material of the elastic member 36 has a lower hardness than the constituent material of the coil spring 35 and a higher hardness than the constituent material of the elastic member 37. The elastic member 36 is made of, for example, an elastomer, urethane rubber, or the like. Further, the elastic member 36 may be made of a metal material as long as it is a member having structural elasticity such as a spring washer. However, since the coil spring 35 is made of metal, it is easily damaged when the metal members collide with each other in the surging phenomenon. Therefore, the elastic member 36 is preferably made of a non-metal material.

Further, the volume of the elastic member 37 is larger than the volume of the elastic member 36. The impact mitigation property of the elastic member 37 improves in proportion to the volume of the elastic member 37. On the other hand, the elastic member 36 may have a small volume as long as it can transmit an impact to the elastic member 37 as described above. Therefore, when the volume of the elastic member 37 is larger than the volume of the elastic member 36, the performance of alleviating the impact due to the surging phenomenon can be improved.

Further, as shown in FIG. 6, in a plan view of the elastic member 36 and the elastic member 37 from the second end side of the coil spring 35 (see FIG. 3), each of the elastic member 36 and the elastic member 37 is circular or circular. It has a ring-shaped planar shape. The diameter DM2 of the outer edge of the elastic member 37 is smaller than the diameter DM1 of the outer edge of the elastic member 36.

In this case, as shown in FIG. 7, the volume of the space 37S between the outer edge of the elastic member 37 and the wall surface of the counterweight 18 (specifically, the wall surface facing the outer surface of the elastic member 37) can be increased. can. In order for the elastic member 37 to be elastically deformed, it is preferable that the volume of the space around the elastic member 37 is large. In the case of the example shown in FIGS. 6 and 7, the volume of the space 37S is increased by shortening the length of the outer edge DM2 of the elastic member 37. As a result, when the surging phenomenon occurs, the elastic member 37 can be easily elastically deformed, so that the impact force mitigation characteristic can be improved.

Further, as shown in FIG. 3, an elastic member 38 is interposed between the plunger 40 and the first end portion of the coil spring 35. The elastic member 38 is made of, for example, the same material as the elastic member 36. In the above, the surging phenomenon between the second end of the coil spring 35 and the counterweight 18 has been described. When the energy of the coil spring 35 is strengthened, the frequency of surging phenomenon also increases between the first end portion of the coil spring 35 and the plunger 40. In particular, when the counterweight 18 is arranged on the second end side of the coil spring 35 as in the driving machine 10, when the striking portion 12 shown in FIG. 1 strikes the fastener 25, the counterweight 18 is used. The plunger 40 moves in the opposite direction to the moving direction. Therefore, the plunger 40 and the first end portion of the coil spring 35 are easily separated from each other after being hit, and a surging phenomenon is particularly likely to occur.

Therefore, in the example shown in FIG. 3, the elastic member 38 is arranged between the plunger 40 and the first end portion of the coil spring 35. In this case, even if a surging phenomenon occurs between the plunger 40 and the first end of the coil spring 35, the first end of the coil spring 35 collides with the elastic member 38 and directly collides with the plunger 40. do not do. Therefore, damage to the first end side of the coil spring 35 can be suppressed.

Further, the elastic member 38 is made of the same material as the elastic member 36. That is, the material of the elastic member 38 has a lower hardness than the constituent material of the coil spring 35, and has a higher hardness than the constituent material of the elastic member 37. Therefore, even if the elastic member 38 and the first end portion of the coil spring 35 repeatedly collide with each other, damage to the elastic member 38 can be suppressed. By the way, since the elastic member 38 is harder than the elastic member 37, the characteristic of alleviating the impact caused by the collision of the coil spring 35 is relatively low. However, as compared with the case where the elastic member in contact with the coil spring 35 is not arranged between the plunger 40 and the coil spring 35, damage to the coil spring 35 due to the surging phenomenon can be reduced.

<Modification 1>
It is preferable to further add an elastic member 39 that is easily elastically deformed, such as the driving machine 10A shown in FIG. In the modified example shown in FIG. 8, the elastic member 39 is interposed between the plunger 40 and the elastic member 38. The elastic member 39 is made of the same material as the elastic member 37 shown in FIG.

The elastic member 38 is in contact with the first end of the coil spring 35. Further, the elastic member 39 is in contact with the elastic member 38 and the plunger 40 and is separated from the coil spring 35. In this case, since the elastic member 39 does not come into contact with the coil spring 35, damage to the elastic member 39 due to the surging phenomenon can be suppressed. Therefore, it is effective even when the energy (repulsive force) of the coil spring 35 is increased.

<Modification 2>
Although not shown, as another modification to the driving machine 10 shown in FIG. 1, there is a modification in which the elastic member 36 and the elastic member 37 shown in FIG. 3 are provided and the elastic member 38 is not provided. .. In this case, damage to the coil spring 35 due to the surging phenomenon between the coil spring 35 and the counterweight 18 can be suppressed. On the other hand, since the first end portion of the coil spring 35 comes into contact with the plunger 40, if a surging phenomenon occurs between the plunger 40 and the coil spring 35, the coil spring 35 may be damaged.

Since the materials and structures of the elastic member 36 and the elastic member 37 are the same as in the case of the driving machine 10 already described, overlapping description will be omitted.

<Modification 3>
As shown in FIG. 9, the above technique can also be applied to the driving machine 10B having no counterweight 18 (see FIG. 3). In the case of the driving machine 10B, the elastic member 36 and the elastic member 37 are interposed between the top holder 31 of the frame and the second end portion of the coil spring 35 in order from the second end portion side of the coil spring 35. The elastic member 36 is in contact with the second end of the coil spring 35. The elastic member 37 is in contact with the elastic member 36 and the top holder 31 and is separated from the coil spring 35.

The surging phenomenon occurs between the top holder 31 and the coil spring 35 shown in FIG. 9 even without the counterweight 18 shown in FIG. In the case of the driving machine 10B, since the elastic member 36 and the elastic member 37 are arranged between the coil spring 35 and the top holder 31, the impact due to the surging phenomenon can be alleviated and the durability of the elastic member 37 can be reduced. It is possible to improve the sex.

In the case of the driving machine 10B, only the plunger 40 is differentiated by the rotational force of the electric motor 14 (see FIG. 1). Therefore, of the first gear 50, the second gear 51, and the third gear 52 shown in FIG. 4, the third gear 52 that differentials the counterweight 18 is unnecessary in the case of the driving machine 10B.

Since the materials and structures of the elastic member 36 and the elastic member 37, or the structure between the plunger 40 and the coil spring 35 are the same as in the case of the driving machine 10 already described, overlapping description will be omitted. Further, this modification can be applied in combination with the technique described in the above-mentioned modification 1 or modification 2.

<Modification example 4>
As shown in FIG. 10, the above technique can be applied to the driving machine 10C in which a plurality of coil springs 35A and 35B are arranged between the top holder 31 and the bottom holder 32.

The urging member of the driving machine 10C includes a coil spring 35A and a coil spring 35B arranged so as to include the coil spring 35A. As shown in FIG. 11, each of the elastic member 36 and the elastic member 37 is arranged at a position overlapping with both the first coil spring 35A and the second coil spring 35B.

In the case of the driving machine 10C using a plurality of coil springs 35A and 35B as the urging member, the energy of the urging member is further increased, so that the speed of the plunger when striking the striking portion 12 (see FIG. 1) becomes high. Therefore, the ends of the coil springs 35A and 35B move violently at the time of hitting, and the behavior is not stable. As a result, surging phenomenon is likely to occur.

As shown in FIG. 11, since each of the elastic member 36 and the elastic member 37 is arranged at a position where they overlap with both the first coil spring 35A and the second coil spring 35B, damage to the coil spring 35A and the coil spring 35B due to surging is suppressed. can.

Further, as shown in FIG. 12, an elastic member 38 and an elastic member 39 are arranged between the first ends of the coil spring 35A and the coil spring 35B and the plunger 40. Each of the elastic member 38 and the elastic member 39 is arranged at a position overlapping with both the first coil spring 35A and the second coil spring 35B.

As described above, in the case of the driving machine 10C using a plurality of coil springs 35A and 35B, the energy of the urging member is further increased, so that the elastic member is located between the plunger 40 and the first end portion of the coil springs 35A and 35B. It is preferable to improve the impact mitigation characteristics by interposing the 38 and the elastic member 39.

Further, as a modification, there is a case where the elastic member 39 is not interposed between the first end portions of the coil spring 35A and the coil spring 35B and the plunger 40, but only the elastic member 38 is interposed. In this case, the characteristic of cushioning the impact is lower than that of the driving machine 10C. However, the impact can be mitigated as compared with the case where the elastic member is not arranged between the first end portions of the coil spring 35A and the coil spring 35B and the plunger 40.

Further, as shown in FIGS. 10 to 12, the winding direction of the coil spring 35A and the winding direction of the coil spring 35B are opposite to each other. For example, when the coil spring 35A is wound clockwise, the coil spring 35B is wound counterclockwise. In this case, when the coil spring 35A and the coil spring 35B move violently due to the impact at the time of impact, it is possible to prevent them from being entangled with each other.

Except for the above-mentioned differences, the detailed structure of the driving machine 10C is the same as that of the driving machines 10, 10A, or 10B already described, so duplicate description will be omitted.

10 ... driving machine, 12 ... hitting part, 18 ... counterweight, 31 ... top holder, 32 ... bottom holder, 35, 35A, 35B ... coil spring, 40 ... plunger, 36, 37, 38, 39 ... elastic member

Claims (12)

With the motor
The housing in which the motor is housed and
A batter blade provided with a driver blade for driving a fastener and a plunger to which the driver blade is attached,
A urging member having a first end portion on the plunger side of the striking portion and a second end portion on the opposite side of the first end portion and driven by the rotational force of the motor.
A first support portion provided on the first end side of the urging member, and
It has a second support portion arranged on the second end side of the urging member, and has.
The plunger is arranged between the first support portion and the urging member.
A first elastic member and a second elastic member are arranged between the second support portion and the second end portion of the urging member in order from the second end portion side of the urging member.
The first elastic member is a driving machine having a hardness lower than that of the urging member and a hardness higher than that of the second elastic member . With the motor
The housing in which the motor is housed and
A batter blade provided with a driver blade for driving a fastener and a plunger to which the driver blade is attached,
A urging member having a first end portion on the plunger side of the striking portion and a second end portion on the opposite side of the first end portion and driven by the rotational force of the motor.
A counterweight arranged on the second end side of the urging member and driven by the rotational force of the motor in a direction opposite to the moving direction of the plunger.
A first support portion provided on the first end side of the urging member, and
It has a second support portion arranged on the second end side of the urging member, and has.
The plunger is arranged between the first support portion and the urging member.
The counterweight is arranged between the second support portion and the urging member.
A first elastic member and a second elastic member are arranged between the counterweight and the second end portion of the urging member in order from the second end portion side of the urging member.
The first elastic member is a driving machine having a hardness lower than that of the urging member and a hardness higher than that of the second elastic member . The first elastic member is in contact with the second end of the urging member.
The driving machine according to claim 2 , wherein the second elastic member is in contact with the first elastic member and the counterweight, and is separated from the urging member. In a plan view of the first elastic member and the second elastic member from the second end side of the urging member.
Each of the first elastic member and the second elastic member has a circular or ring-shaped planar shape.
The driving machine according to any one of claims 1 to 3 , wherein the diameter of the outer edge of the second elastic member is smaller than the diameter of the outer edge of the first elastic member. The driving machine according to any one of claims 1 to 4 , wherein a third elastic member is interposed between the plunger and the first end portion of the urging member. The driving machine according to claim 5 , wherein the third elastic member is made of the same material as the first elastic member. A fourth elastic member is interposed between the plunger and the third elastic member.
The fourth elastic member is made of the same material as the second elastic member.
The third elastic member is in contact with the first end portion of the urging member.
The driving machine according to claim 6 , wherein the fourth elastic member is in contact with the third elastic member and the plunger and is separated from the urging member. The driving machine according to any one of claims 1 to 7 , wherein the volume of the second elastic member is larger than the volume of the first elastic member. The driving machine according to any one of claims 1 to 8 , wherein the first elastic member is made of a non-metal material. The driving machine according to any one of claims 1 to 9 , wherein the second elastic member is rubber. The urging member includes a first coil spring and a second coil spring arranged so as to include the first coil spring.
The driving machine according to any one of claims 1 to 10 , wherein each of the first elastic member and the second elastic member is arranged at a position where both the first coil spring and the second coil spring overlap. .. The driving machine according to claim 11 , wherein the first coil spring or the second coil spring has an elliptical cross section.

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