Patent Application
20060185489
The present invention relates to an electric paper cutter wherein the operation mechanism of the pressing board is driven by a motor which is stopped when the pressing board presses on the paper pile.
A pressing board assembly 60 of a conventional manual paper cutter is disclosed in
The present invention intends to provide an operation mechanism for operation of pressing board of an electric paper cutter wherein the travel of the pressing board is controlled by sensors which send commands to stop the motor when the pressing board presses on the pile of paper.
The present invention relates to a pressing board operation mechanism for electric paper cutters and the mechanism comprises a driving assembly which has a motor which drives a driving and a transmission wheel is driven by the driving gear. A driving rod has an end eccentrically connected to the transmission wheel and the other end of the driving rod is pivotably connected to a first link assembly which includes two first plates and two second plates. The first plates are pivotably connected to one of the two side fixing portions and the other end of the driving rod is pivotably connected to the two first plates. A pivotable member is pivotably clamped between the two first plates and a push rod has a threaded end which extends through a sleeve, a spring, a washer, a hole in the pivotable member and is threadedly connected to an adjusting nut. The spring is received in the sleeve and rested on a first flange extending from an inner periphery of a first end the sleeve. The adjusting nut extends through the hole in the pivotable member and is in contact with the spring. A second flange extends from an outer periphery of a second end of the sleeve. The two second plates are pivotably connected to the frame and the other end of the push rod is pivotably connected to the two second plates. A first end of a connection plate is pivotably connected to the second plates. Two sensors are connected to the frame and the first plate respectively, and the two sensors can be activated by the flange of the sleeve and a side of the two second plates respectively.
A second link assembly has a rack member which has two rack portions on two sides thereof. A second end of the connection plate is pivotably connected to the rack member. Two first links are pivotably connected to a side board and each of the first links has a rack end which is engaged with one of the rack portions of the rack member. Two limitation boards are pivotably connected between the rack member and the two first links. Two second links each have a first end pivotably connected to the first link corresponding thereto and a second end of each of the second links is pivotably connected to the pressing board.
The present invention will become more obvious from the following description when taken in connection with the accompanying drawings which show, for purposes of illustration only, a preferred embodiment in accordance with the present invention.
Referring to
A driving assembly 20 includes a motor 21 and a driving gear 22 which is driven by the motor 21. A transmission wheel 23 is driven by the driving gear 22 and a driving rod 24 has an end eccentrically connected to the transmission wheel 23.
A first link assembly 30 has two first plates 31 and two second plates 32. The first plates 31 each have a first point “a” pivotably connected to one of the two side fixing portions 11 and the other end of the driving rod 24 is pivotably connected to a second point “b” of the two first plates 31. A pivotable member 33 is pivotably clamped between the two first plates 31 at a third point “c” of the first plates 31. A push rod 35 has a threaded end 351 which extends through a sleeve 36, a spring 37, a washer 38, a hole 331 in the pivotable member 33 and is threadedly connected to an adjusting nut 39. The spring 37 is received in the sleeve 36 and rested on a first flange extending from an inner periphery of a first end the sleeve 36. The push rod 35 has a protrusion 352 extending radially outward from a mediate portion thereof and the first end of the sleeve 36 is stopped by the protrusion 352 when the spring 37 is compressed. The adjusting nut 39 extends through the hole 331 in the pivotable member 33 and is in contact with the spring 37. A second flange 361 extends from an outer periphery of a second end of the sleeve 36. The two second plates 32 each have a first point pivotably connected to the frame 10 and the other end of the push rod 35 is pivotably connected to a second point of the two second plates 32. A third point of the second plates 32 is pivotably connected to a first end of a connection plate 34.
Two sensors 40 such as limit switches are respectively connected to the frame 10 and the pivotable member 33. The sensor 40 connected to the pivotable member 33 is activated by the flange 361 of the sleeve 36 and the other sensor 40 on the frame 10 can be activated by a side of the two second plates 32.
A second link assembly 50 has a rack member 51 which has two rack portions 511 on two sides thereof and a second end of the connection plate 34 is pivotably connected to the rack member 51. Two first links 54 are pivotably connected to a side board 12 at holes 121 in the side board 12 by pins 53, and each of the first links 54 has a rack end which is engaged with one of the rack portions 511 of the rack member 51. Two limitation boards 52 are pivotably connected between the rack member 51 and the two first links 54. Two second links 55 each have a first end pivotably connected to the first link 54 corresponding thereto and a second end of each of the second links 55 is pivotably connected to the holes 132 of the pressing board 13.
As shown in
The compression of the spring 37 can be adjusted by rotating the adjusting nut 39 on the threaded end 351 of the push rod 35 so that the force used for overcoming the reaction force from the pile of paper “P” can be adjusted.
The motor 21 automatically stops and is protected when pressing the pile of paper “P” and the user needs not to check the time to turn off the motor 21.
While we have shown and described the embodiment in accordance with the present invention, it should be clear to those skilled in the art that further embodiments may be made without departing from the scope of the present invention.
