Driving Force Adjusting PICK-UP Device And The Driving Force Adjusting Method Thereof

Abstract

A driving force adjusting pick-up device, includes: a transmitting path; a pick roller disposed in the transmitting path for transmitting papers; an actuating unit connected with the pick roller to adjust the normal force applied to the paper; a separating unit disposed in the transmitting path and located downstream to the pick roller; and a driving force measuring unit which includes a first speed measuring roller disposed upstream to the separating unit and a second speed measuring roller disposed downstream to the separating unit for measuring transmitting speed of the paper upstream and downstream to the separating unit; wherein the driving force measuring unit evaluates the driving force applied to the paper by comparing transmitting speed of the paper upstream and downstream to the separating unit.

Claims

1. A driving force adjusting pick-up device, comprising: a transmitting path; a pick roller disposed in the transmitting path for transmitting paper; an actuating unit connected with the pick roller to adjust a normal force applied to the paper; a separating unit disposed in the transmitting path and located downstream to the pick roller; and a driving force measuring unit which includes a first speed measuring roller disposed upstream to the separating unit for measuring transmitting speeds of the paper upstream of the separating unit and a second speed measuring roller disposed downstream to the separating unit for measuring transmitting speeds of the paper downstream of the separating unit, the first and second speed measuring rollers being disposed on a same side of the transmitting path for measuring the transmitting speeds on one side of the paper; wherein the driving force measuring unit evaluates a driving force applied to the paper by comparing the transmitting speeds of the paper upstream and downstream of the separating unit.

2. The driving force adjusting pick-up device as claimed in claim 1, wherein the actuating unit comprises a pick-up arm with a free end connected to the pick roller and a pivot end that pivotally connects to the structure of the pick-up device to cause the free end swinging in a direction that is substantially perpendicular to the transmitting path; a solenoid with a fixed end and an actuating end that connects to the pick-up arm for pushing the pick-up arm toward the paper and increasing the normal force between the pick roller and the paper.

3. The driving force adjusting pick-up device as claimed in claim 2, wherein the fixed end is connected with the structure of the pick-up device, and a connecting line between the fixed end and the actuating end of said solenoid is offset from the pivot end to cause the pick-up arm generating a torque that causes the free end to approach the paper when the solenoid acts.

4. The driving force adjusting pick-up device as claimed in claim 2, wherein the actuating unit further comprises a returning spring which connects between the structure of the pick-up device and the pick-up arm for pulling the pick-up arm away from the paper, and thereby reducing the normal force between the pick roller and the paper.

5. The driving force adjusting pick-up device as claimed in claim 4, wherein the returning spring is a tension spring that is arranged offset from a pivot shaft for generating a torque in a direction opposite to a torque generated by the solenoid, and thus moving the pick roller away from the paper.

6. The driving force adjusting pick-up device as claimed in claim 1, wherein the actuating unit has a pick-up arm and a solenoid connected to the pick-up arm, the pick-up arm connects to the pick roller, the solenoid pushes the pick-up arm to move the pick roller toward the paper for increasing the normal force between the pick roller and the paper.

7. The driving force adjusting pick-up device as claimed in claim 6, wherein the actuating unit has a returning spring connected to the pick-up arm, the returning spring pulls the pick-up arm to move the pick roller away from the paper for reducing the normal force between the pick roller and the paper.

8. The driving force adjusting pick-up device as claimed in claim 7, wherein the returning spring is set to a tension.

9. A method for adjusting the driving force of a pick-up device, including the following steps: applying a predetermined amount of driving force to paper via a pick roller disposed in a transmitting path to feed the paper through a separating unit; obtaining a preset transmitting speed (V0) of the pick roller; measuring a transmitting speed (V1) of the paper before passing through the separating unit with a first speed measuring roller and a transmitting speed (V2) after passing through the separating unit with a second speed measuring roller; increasing the driving force of the pick roller applied to the paper when the transmitting speed (V0) is greater than the transmitting speed (V1), and decreasing the driving force of the pick roller applied to the paper when the transmitting speed (V1) is greater than the transmitting speed (V2); wherein the first and second speed measuring rollers are disposed on a same side of the transmitting path for measuring the transmitting speeds (V1) and (V2) on one side of the paper.

10. The method for adjusting the driving force of a pick-up device as claimed in claim 9, wherein the driving force is increased by increasing a normal force between the pick roller and the paper and reduced by reducing the normal force between the pick roller and the paper.

Description

BRIEF DESCRIPTION OF THE DRAWINGS

[0018] The present invention will be apparent to those skilled in the art by reading the following description, with reference to the attached drawings, in which:

[0019] FIG. 1 shows a side view of the pick-up device in the present invention.

[0020] FIG. 2 shows a perspective view of the pick-up device in the present invention.

[0021] FIG. 3 shows a block diagram of adjusting the driving force to the paper in the present invention.

[0022] FIG. 4 shows a side view of a conventional pick-up device.

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT

[0023] In order to describe the technical contents, structural features, purpose to be achieved and the effectiveness of the present invention, the detailed description is given with schema below.

[0024] Referring to FIG. 1, the driving force adjusting pick-up device 10 in the present invention includes a transmitting path 11, a pick roller 30 arranged in the transmitting path 11 for transmitting paper, a actuating unit 20 connected to the pick roller 30 for adjusting the normal force between the pick roller 30 and the paper, a separating unit 40 which is arranged in the transmitting path 11 and located downstream to the pick roller 30, and a driving force measuring unit 50 which includes a first speed measuring roller 51 disposed upstream to the separating unit 40 and a second speed measuring roller 52 disposed downstream to the separating unit 40, and said driving force measuring unit 50 measuring the driving force applied to the paper by comparing the feeding velocity measured by the first speed measuring roller 51 and the second speed measuring roller 52.

[0025] Referring to FIG. 2, the actuating unit 20 in this embodiment includes a pick-up arm 21 pivotly connected above the transmitting path 11, a solenoid 22 and a returning spring 23. The pick-up arm 21 includes a pivot end 21a which is pivotly connected with the structure (not shown) of the pick-up device 10 and a free end 21b connected with the pick roller 30 to ensure the free end 21b swing along the direction that essentially perpendicular to the transmitting path 11. The solenoid 22 includes a fixed end 22a which is connected to the structure (not shown) of the pick-up device 10 and an actuating end 22b connected with the pick-up arm 21. The fixed end 22a and the actuating end 22b of the solenoid 22 are both disposed above the pivot end 21a, so that the force applied by the solenoid 22 generates a torque in counter-clock-wise to swing the free end 21b toward the paper and increase the normal force between the pick roller 30 and the paper. The returning spring 23 in this embodiment is a tension spring that arranged on the opposite side of the solenoid 22. One end of the returning spring 23 is connected the structure (not shown) of the pick-up device 10 and the other end of the returning spring 23 is connected to the pick-up arm 21, so that the rightward drag force applied by the returning spring 23 generates a torque in clock-wise to swing the free end 21b away from the paper and decrease the normal force between the pick roller 30 and the paper. With the cooperating of the solenoid 22 and the returning spring 23, the actuating unit 20 in the present invention is capable to adjust the driving force applied to the paper.

[0026] Referring to FIG. 3 now, the process of adjusting the driving force as shown as follow: Applies a predetermined driving force to the paper via the pick roller 30 to transmit said paper passing through the separating unit. Obtains the preset transmitting speed (V0) of the pick roller 30 by evaluating the rotating speed of the pick roller 30, and the transmitting speed of the paper to be fed is normally equal to the preset transmitting speed (V0) of the pick roller 30. And then checks whether the paper is fed normally via the driving force measuring unit 50, the driving force measuring unit 50 measures the transmitting speed (V1) of the paper before the separating unit 40 and the transmitting speed (V2) of the paper pass through the separating unit 40. If the preset transmitting speed (V0) is greater than the transmitting speed (V1), that means the paper doesn't receive enough driving force so the paper does not move as fast as the preset transmitting speed (V0) of the pick roller 30. In this case, increasing the output force of the solenoid 22 to force the pick-up arm 21 approaching the paper and increasing the normal force and driving force applied to the paper to ensure the paper is correctly fed. In opposite, if the transmitting speed (V1) is greater than the transmitting speed (V2), and that means the paper receives too much driving force, and the output force of the solenoid 22 needs to be reduce to prevent the paper from being pushed and wrinkled. At this time, the pick-up arm 21 will be draw away from the paper under the action of the returning spring 23, thereby reducing the normal force and driving force applied to the paper by the pick roller 30.

[0027] In summary, the present invention discloses a pick-up device 10, which measures the speed of paper being fed through with the first and second speed measuring roller 51, 52 disposed respectively on upstream and downstream side of the separating unit 40 to determine the paper feeding status, and thereby automatically adjust the driving force applied on the paper according to the paper feed status.