Claims
- 1. A power tool for setting blind rivets by tensioning a mandrel of a blind rivet until the mandrel becomes severed, comprising a housing; a mandrel pulling unit disposed in said housing and comprising a gripper movable between an extended position for engagement with a mandrel and a retracted position to sever an engaged mandrel during movement from said extended position; and means for moving said gripper including an electric motor and a transmission interposed between said gripper and said motor within said housing, the electric motor being reversible and the transmission being permanently operatively coupled directly between the electric motor and the gripper such that the movement of the gripper in a first axial direction occurs without the use of a restoring spring when the electric motor rotates in a first direction and the movement of the gripper in an opposite second axial direction occurs without the use of a restoring spring when the electric motor rotates in an opposite second direction.
- 2. The power tool of claim 1, further comprising means for operating said motor, said motor and said transmission constituting the only means for moving the gripper between said positions thereof.
- 3. The power tool of claim 2, wherein said transmission comprises a spindle member, a nut member mating with said spindle member and antifriction rolling elements interposed between said members, one of said members being rotatable by said motor and the other of said members being reciprocable with said gripper.
- 4. The power tool of claim 3, wherein said one member is said nut member.
- 5. The power tool of claim 4, wherein said nut member comprises a gear and said transmission further comprises means for rotating said gear in response to operation of said motor.
- 6. The power tool of claim 3, wherein said gripper and said spindle member define a path for evacuation of a severed mandrel from said unit.
- 7. The power tool of claim 6, wherein said path includes a longitudinal passage in said spindle member.
- 8. The power tool of claim 7,
- wherein said housing comprises a tube for evacuation of severed mandrels from said path, said tube being telescoped into said passage and said spindle member being reciprocable with said gripper relative to said tube and said nut member.
- 9. The power tool of claim 3, further comprising a hollow mouthpiece provided in said housing and aligned with said gripper, and a thrust bearing between said mouthpiece and said nut member, said mouthpiece defining an inlet for introduction of a mandrel into said gripper.
- 10. The power tool of claim 3,
- wherein said spindle member is reciprocable with said gripper in response to rotation of said nut member by said motor, and further comprising at least one abutment reciprocable with said spindle member and being arrested by said nut member against further movement, in response to movement of said gripper and said spindle member to a predetermined end position relative to said housing and said nut member.
- 11. A power tool for setting blind rivets by tensioning a mandrel of a blind rivet until the mandrel becomes severed, comprising a housing; a mandrel pulling unit disposed in said housing and comprising a gripper movable between an extended position for engagement with a mandrel and a retracted position to sever an engaged mandrel during movement from said extended position; and means for moving said gripper including an electric motor and a transmission interposed between said gripper and said motor, the electric motor being reversible and the transmission being permanently operatively coupled directly between the electric motor and the gripper such that the movement of the gripper in a first axial direction occurs without the use of a restoring spring when the electric motor rotates in a first direction and the movement of the gripper in an opposite second axial direction occurs without the use of a restoring spring when the electric motor rotates in an opposite second direction;
- means for operating said motor, said motor and said transmission constituting the only means for moving the gripper between said positions thereof;
- a spindle member, a nut member mating with said spindle member and antifriction rolling elements interposed between said members, one of said members being rotatable by said motor and the other of said members being reciprocable with said gripper;
- a hollow mouthpiece provided in said housing and aligned with said gripper, and a thrust bearing between said mouthpiece and said nut member, said mouthpiece defining an inlet for introduction of a mandrel into said gripper; and
- wherein said nut member has a first axial end and a second axial end, said mouthpiece being disposed at one axial end of said nut member, said housing comprising a cage at least partially confining said nut member and further comprising a second thrust bearing between said cage and the other axial end of said nut member.
- 12. A power tool for setting blind rivets by tensioning a mandrel of a blind rivet until the mandrel becomes severed, comprising a housing;
- a mandrel pulling unit disposed in said housing and comprising a gripper movable between an extended position for engagement with a mandrel and a retracted position to sever an engaged mandrel during movement from said extended position; and means for moving said gripper including an electric motor and a transmission interposed between said gripper and said motor;
- further comprising means for operating said motor, said motor and said transmission constituting the only means for moving the gripper between said positions thereof;
- wherein said motor is reversible and said operating means includes an on/off switch actuatable by an operator and a circuit including means for operating said motor in a first direction in response to actuation of said switch and in a second direction in response to termination of actuation of said switch.
- 13. The power tool of claim 12, wherein said circuit further comprising means for short circuiting said motor for a predetermined interval of time in immediate response to termination of actuation of said switch.
- 14. The power tool of claim 12, wherein said circuit further comprises at least one signal generating switching device which is operable by said switch.
- 15. The power tool of claim 14, wherein said circuit further comprises means for delaying the generation of a signal by said at least one device in response to operation of said at least one device by said switch.
- 16. The power tool of claim 15, wherein said motor comes to a halt within a first interval of time in response to short circuiting by said short circuiting means, said delaying means being operative to delay the generation of a signal for a second interval of time which at least approximates said first interval.
- 17. The power tool of claim 12, wherein said circuit further comprises two discrete means for short circuiting said motor for predetermined intervals of time in response to termination of actuation of said switch.
- 18. The power tool of claim 17, wherein each of said short circuiting means comprises a switchover device.
- 19. The power tool of claim 12, wherein said transmission comprises a spindle member which is reciprocable by said motor and is connected with said gripper, and further comprising an energy source for said motor, said operating means comprising at least one limit switch having means for disconnecting said motor from said energy source in response to movement of said spindle member to a predetermined position.
- 20. The power tool of claim 19, wherein said operating means comprises a circuit including said at least one limit switch and a second switch actuatable by an operator to start said motor, said circuit further comprising at least one signal generating switching device which is operable by said second switch and means for delaying the generation of a signal by said at least one signal generating device for a predetermined interval of time in response to operation of said at least one device by said second switch, said at least one limit switch comprising means for deactivating said delaying means in response to movement of said spindle member to said predetermined position.
- 21. The power tool of claim 20, wherein said at least one signal generating switching device is operated by said at least one limit switch.
Priority Claims (1)
Number |
Date |
Country |
Kind |
41 26 602 |
Aug 1991 |
DEX |
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Parent Case Info
This is a continuation of application Ser. No. 07/925,444, filed Aug. 11, 1992, now abandoned.
US Referenced Citations (6)
Foreign Referenced Citations (5)
Number |
Date |
Country |
0062869 |
Oct 1982 |
EPX |
0116954 |
Aug 1984 |
EPX |
49-127274 |
Dec 1974 |
JPX |
2-137638 |
May 1990 |
JPX |
9111279 |
Aug 1991 |
WOX |
Continuations (1)
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Number |
Date |
Country |
Parent |
925444 |
Aug 1992 |
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