Oil dispenser for simplex and duplex print engine

Abstract

This is a mechanical oil dispenser for use in applying an oil to the surface (or two surfaces in a duplex mode) of printed media to improve its sheet-handling characteristics. This dispenser system has an oil-containing housing or tank with oil ports at the bottom of the tank. The ports are abutting a wick, this wick then disperses oil to an applicator roll which in turn applies oil to one or both surfaces of a printed media. The oil ports and oil flow are controlled by the profile of a cam and shaft in operative connection to said ports. Opening and closing of these oil ports are controlled by a cam shaft movement actuated by the rotation and stopping of the applicator roll.

Description

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 illustrates a front view of a dispensing unit embodiment where the oil dispensing ports are open.

FIG. 2 illustrates a front view of a dispensing unit embodiment where the oil ports are closed.

FIG. 3 illustrates a side view of a dispensing unit embodiment of the dispensing cam mechanism and wrap-spring clutch control.

FIG. 4 illustrates a duplex oil dispenser system for a duplex continuous feed machine.

FIG. 5 illustrates a duplex oil dispenser with a drive nip.

DETAILED DESCRIPTION OF THE DRAWINGS AND PREFERRED EMBODIMENTS

In FIG. 1, a front view of an embodiment of a dispensing unit 1 of this invention is shown with oil ports 2 open. In FIG. 2, a front view of this embodiment is shown with oil ports 2 closed.

An oil dispensing unit 1 of the present invention mainly consists of an oil tank 3, a wick 4, an applicator roll 5, a cam shaft 6 and plunger assembly 7 and a wrap-spring clutch 11 assembly as shown In FIG. 3. In FIG. 1, which is a front view, an oil tank 3 having a wick 4 at the bottom is mounted on top of an applicator roll 5. The wick 4 is saturated with lubricating oil 8 which is fed by gravity through an array of oil ports 2 distributed along the width and length of the wick 4. A wick 4 useful in the present invention is preferably made up of a layer of Teflon felt or fiber needled to a fibrous or felted Nomex material. The Nomex layer is in contact with the applicator roll. Teflon and Nomex are trademarks of E.I. du Pont Co. of Wilmington, Del. The construction of an oil wick 4 is well known in the art. Above the oil ports 2 are movable elastomer blocks or oil port blocks 9 which are mounted on the bottom of a plunger bar 7 and cam follower 7′. The up and down movement of the plunger bar 7 is governed by the rotation of the cam shaft assembly 6 and cam 20. The cam shaft assembly 6 has multiple identical cam elements 20 which are equally located near the front end and the rear end of the oil tank 3. Each cam element 20 has the same off-center profile that determines the gap of the flow channel at different rotation angle of the cam shaft 6. Cam 20 has a tear drop profile with a projection 21. When projection 21 is in an upper position (as in FIG. 1) the oil port 2 is open. When cam projection 21 is in a lower or closed or home position (FIG. 2), the oil port 2 is closed by oil port blocks 9. FIG. 1 shows the cam shaft at the fully open position. FIG. 2 shows the cam shaft 6 and cam 20 in the closed port or home position.

The applicator roll is driven independently by a motor or by a drive chain 22 engaged with the drive mechanism 10 of a host engine (not shown in the Figures). FIG. 3 shows a side view of the oil dispensing unit 1 indicating the rotational engagement of the cam shaft 6 with a wrap-spring clutch 11 whose input hub is rotated with the applicator roll 5. The wrap-spring clutch 11 has the one-way feature allowing rotation only in one direction and its practice is well known in the art. When the input hub 10 is rotated with the applicator roll 5, the internal spring wraps down and engages the input to the output hub 12 which is engaged with the cam shaft 6. The cam shaft 6 is spring loaded and biased toward the home position (as shown in FIG. 2). When the applicator roll 5 is stopped, the internal spring unwraps allowing the cam shaft 6 to return to the home position. Furthermore, the clutch 11 can be used with different stop limits which can be set by a dial feature (not shown). With the dial feature the clearance of the flow channel gap 13 can be adjusted mechanically for providing different rate. FIG. 3 also shows the structure of the plunger bar 7. The plunger bar 7 has closed loops at both ends functioning as cam followers 7′ that are integrated with the rigid open support at the center. The open space is for oil 8 volume which extends to the flow channel gap 13. Attached to the bottom of the plunger bar 7 are elastomer blocks or port blocking components 9 for covering and sealing the oil ports 2 when the cam shaft 6 is at the closed or the home position. These oil ports 2 are distributed along the bottom of the oil tank or housing 3 to allow the oil 8 being fed by gravity into the wick 4.

In practice, an oil dispensing unit 1 of the present invention is placed in the paper path of a printer (not shown) with the applicator roll 5 in contact with the print sheet 14 on the side to be applied with oil 8. The applicator roll 5 is either driven by a motor or connected to the drive system 10 of the host printer. Upon rotation of the applicator roll 5, the wrap-spring clutch 11 is activated such that the cam shaft 6 and cam 20 are rotated against a spring force to the predetermined stop limit which is mechanically set by a built-in dial. The cam rotation opens the oil ports 2 and sets the clearance of the flow channel gap 13 that determines the oil rate into the wick 4. The wick 4 dispenses oil film to the applicator roll 5 that deposits the oil 8 to the print sheet 14. The system maintains constant applicator roll speed and the oil rate is adjusted by the flow gap, if needed. When the host machine drive or the motor stops, the cam shaft 6 and cam 20 returns to the home position by the spring force and closes the oil ports 2.

In one embodiment for simultaneous duplex printing application, two oil dispensing units 1, as described, where one oil dispensing unit 1 can be integrated with an oil transfer roll 16 for applying oil 8 to a second side (side 2) of a print sheet and sheet transport 14. Another application roll 5 can apply oil 8 to the first side (side 1) of a print sheet 14. FIG. 4 shows a configuration of a duplex oil dispenser for duplex oiling. As an example, the dual oil dispenser as shown is mounted at the exit of a flash fusing duplex printer 15. The oil transfer roll 16 is the drive source of the duplex oil dispenser as it drives the applicator rolls 5 of the two oil dispensing units for actuating the cam shafts 6 for dispensing oil 8. The oil transfer roll 16 is connected to the machine drive of the host engine or optionally driven by an independent motor for running at the sheet speed. Another embodiment is for two applicators in a duplex oil dispenser 23 forming a drive nip 17 as shown in FIG. 5 in which two oil dispensing units 1 are positioned side by side at upright position. In such configuration, the nip force may be designed to flatten flash fused toner images and enhance the fix level. For accommodating potential speed mis-match between drive nips 17 of the oil dispenser 1 and the host engine, and between drive nips 17 of the oil dispenser 1 and the finisher, paper loops 18 are created for avoiding tensioning of the sheet 14 in the paper path. Turn rolls 19 direct and transport paper print sheet 14. In all of the above-described applications, an applicator roll 5 may have rigid metal or rubber surfaces. As earlier noted, any suitable provisions can be made to retrofit the unit of this invention in any existing marking apparatus.

In summary, in an embodiment an oil dispensing system is used for distributing oil to an applicator roll in an image forming apparatus comprising in an operative arrangement a unit comprising an oil tank housing enabled to hold an oil supply, oil ports or openings positioned in a bottom section of the housing, a port and an assembly for controlling the movement of said component to thereby open and close the ports and whereby opening and closing of the oil ports is controlled by a cam shaft movement activated by a rotation and stopping of the applicator roll. This system comprises a wick positioned between said applicator roll and said ports and whereby an open port is enabled to distribute oil to an adjacent wick which is in contact with the applicator roll. In this system, at least one of the oil dispensing units is positioned in the image forming apparatus. This system has any suitable provisions for being retrofitted into any existing flash fusing continuous feed apparatus. The unit is enabled to dispense oil to one surface of a printed sheet. Also, in a duplex mode, the unit is enabled to dispense oil to both surfaces of a printed media sheet.

A retrofit can be made in an electrophotographic marking system using the unit of this invention. This unit comprises in an operative arrangement a printed media and at least two applicator rolls and units comprising at least two oil tank housings with ports using at least two mechanical cam oil flow controls. It has an applicator roll in contact with each of said housings and a wick positioned between each of said housing ports and said applicator rolls. The oil ports are located at bottom portions of each of the housing with movable blocks located adjacent each of the ports. The blocks are positioned by controls to either open or close the ports to dispense oil therefrom or to prevent the flow of oil therethrough. These controls are regulated by a cam shaft movement which is activated by a movement of the applicator roll. This system is enabled to dispense oil to both sides of the sheets to provide thereby duplex oil dispensers wherein the cam has a cam projection which when rotated in a home position will be enabled to cause an oil port block to block the oil port. The cam projection, when rotated in an open position, will be enabled to cause an oil port block to open the oil port to allow oil to flow therethrough to the wick. The at least two units are each located adjacent opposite sides or surfaces of the sheets and enabled to thereby dispense oil to both sides of the sheets.

The duplex oil dispenser of this invention comprises an oil housing adjacent a first applicator roll, and an oil housing adjacent to a second applicator roll. The first applicator roll is enabled to dispense oil to a first side of the printed media and the second applicator is enabled to dispense oil to a second side of the printed media. This system is used whereby a duplex oil dispenser is used having two applicator rolls side by side adjacent each other with each having oil dispensing units in contact therewith. The transport is enabled to pass said printed media between a nip formed in the side by side applicators. This system is used whereby said duplex oil dispenser comprises an oil housing adjacent a first applicator roll in the system, and an oil housing adjacent to a second applicator roll located subsequently to the first applicator roll in the system. The first applicator roll is enabled to dispense oil to a first side of the printed media and the second applicator is enabled to dispense oil to a second side of the printed media.

It will be appreciated that various of the above-disclosed and other features and functions, or alternatives thereof, may be desirably combined into many other different systems or applications. Various presently unforeseen or unanticipated alternatives, modifications, variations or improvements therein may be subsequently made by those skilled in the art which are also intended to be encompassed by the following claims.

Claims

1. An oil dispensing system for distributing oil to an applicator roll in an image forming apparatus comprising in an operative arrangement a dispensing unit comprising an oil tank housing enabled to hold an oil supply, oil ports or openings positioned in a bottom section of said housing, a port blocking component and an assembly for controlling the movement of said component to thereby open and close said ports and whereby opening and closing of said oil ports is controlled by a cam shaft movement activated by a rotation and stopping of said applicator roll.

2. The system of claim 1 comprising a wick positioned between said applicator roll and said ports.

3. The system of claim 1 whereby an open port is enabled to distribute oil to an adjacent wick, said wick in contact with said applicator roll.

4. The system of claim 1 whereby at least one of said oil dispensing units is positioned in said image forming apparatus.

5. The system of claim 1 having provisions for being retrofitted into any existing flash fusing continuous feed apparatus.

6. The system of claim 1 whereby said unit is enabled to dispense oil to one surface of a printed media sheet.

7. The system of claim 1 whereby said unit is enabled to dispense oil to both surfaces of a printed media sheet.

8. An oil dispensing system enabled to distribute oil to a printed sheet in an electrophotographic marking process, said system comprising a unit having in an operative arrangement an oil tank housing, a mechanical cam activated oil flow controlling component, a wick enabled to disperse oil to an applicator roll, and oil ports located in said housing, said controlling component adapted to open said ports to dispense oil therefrom and to close said ports to prevent the flow of oil there through, said flow controlling component is regulated by a cam shaft movement actuated by rotation and stopping of said applicator roll.

9. The system of claim 8 whereby the dispensing of oil is controlled by both said cam's profile and also by rotation limit of a cam shaft of said cam.

10. The system of claim 8 whereby said ports are located at a bottom portion of said housing, and said wick is operatively positioned between said ports and said applicator roll.

11. The system of claim 8 whereby said unit is enabled to dispense oil to one surface of a marked receiving sheet.

12. The system of claim 8 whereby said unit is enabled to dispense oil to both surfaces of a marked receiving sheet.

13. An electrophotographic marking system comprising in an operative arrangement a printed media or paper sheets transport, at least two applicator rolls and units comprising at least two oil tank housings with ports, at least two mechanical cam oil flow controls, and an applicator roll in contact with each of said housings, a wick positioned between each of said housing ports and said applicator rolls, said oil ports located at bottom portions of each of said housings, movable blocks located adjacent each of said ports, said blocks positioned by controls to either open or close said ports to dispense oil therefrom or to prevent the flow of oil there through said controls regulated by a cam shaft movement, said cam shaft activated by a movement of said applicator roll, and said system enabled to dispense oil to both sides of said sheets to provide thereby duplex oil dispensers and wherein said cam has a cam projection which when rotated in a home position said projection will be enabled to cause an oil port block to block said oil port, and said cam projection when rotated in an open position, said projection will be enabled to cause an oil port block to open said oil port to allow oil to flow therethrough to said wick.

14. The system of claim 13 whereby said at least two units, each located adjacent opposite sides or surfaces of said sheets and enabled to thereby dispense oil to both sides of said sheets.

15. The system of claim 13 whereby said duplex oil dispenser comprises an oil housing adjacent a first applicator roll, and an oil housing adjacent to a second applicator roll, said first applicator roll enabled to dispense oil to a first side of said printed media and said second applicator enabled to dispense oil to a second side of said printed media.

16. The system of claim 13 whereby a duplex oil dispenser is used having two of said applicator rolls side by side adjacent each other enabled to be in contact with opposite sides of said printed media, said transport enabled to pass said printed media between a nip formed in said side-by-side applicators.

17. The system of claim 13 whereby said duplex oil dispenser comprises an oil housing adjacent a first applicator roll in said system, and an oil housing adjacent to a second applicator roll located subsequently to said first applicator roll in said system, said first applicator roll enabled to dispense oil to a first side of said printed media and said second applicator enabled to dispense oil to a second side of said printed media.