Gang safety latching mechanism and an image producing machine including same

A gang safety latching mechanism includes (a) a torsion spring and bracket device having (i) a torsion spring subassembly (ii) a first bracket on the torsion spring subassembly having a first free position and a first loaded position, and (iii) a second bracket on the torsion spring subassembly having a second free position and a second loaded position; (b) an interference assembly defining a receiving area and including (i) an opening for passage of an end portion of the torsion spring and bracket device into and out of the receiving area, (ii) a knocker member for contacting the first bracket and (iii) a catch lip for trapping the second bracket within the receiving area; and (c) a gang locking member for locking the second bracket to the first bracket, thereby preventing unsafe separate simultaneous movement of the second movable and the first movable module relative to the main machine body.

This invention relates to a gang safety latching mechanism for preventing unsafe separate simultaneous movement of plural movable co-assembled bodies, and more particularly to an image producing machine including the same.

Image producing machines, for example high speed electrostatographic reproduction machines typically comprise modular assemblies. These modular assemblies typically also include copy sheet handling modules that are individually mountable relative to a host machine, and that are movable linearly or pivotably and separately relative to each other and/or to the host machine in order to provide operator access to necessary operator functions on or within the modules or host machine.

In some of these machines, the architecture may involve one module mounted on another, for example, a bypass sheet transport module being mounted on a sheet compiler input transport module, each of which is movable relative to the other and to another reference module. A typical operator function that requires movement of these modules is jam clearance.

Jam clearance for example may and often requires moving more than one such modules, for example, it may require (i) that the compiler input transport module is opened to clear the compiler area, (ii) that the bypass transport also be opened to clear the compiler input transport itself; and (iii) that a cover to, or the upper portion of the bypass transport module further also be opened to clear the bypass transport module itself. Typically, the two main transport modules in this example, (the bypass transport module and the compiler input transport module) can open 60 and 75 degrees respectively relative to the reference module on which they are mounted. Because each of these modules as mounted is counterbalanced, the ability to open both of them simultaneously tends to undesirably affect the center of gravity of the joint mass being moved, thereby causing the counterbalances to briskly open the both modules in an unsafe manner to their open positions. It should be noted that to both modules when opened simultaneously thus will amount to a vigorous travel through an angle of 135 degrees for the bypass transport module. Such vigorous travel by the bypass transport module, past vertical, runs a significant risk of causing injury to an operator, and/or damage to the hardware or surrounding objects.

In general, the problem described here with such co-assembled modules of an image, producing machine, may also be encountered in similar environments including plural co-assembled and movable modules that similarly may have to be moved separately and simultaneously by an operator in order to perform an operator function.

As disclosed for example in the following references, it is known to attempt to use latching mechanisms in order to lock one component to another. U.S. Pat. No. 4,295,732 issued Oct. 20, 1981 and entitled “Bound document apparatus latching mechanism” discloses a double latch arrangement for use in a reproduction system having a document handling device for the circulation of individual document sheets onto a copying exposure platen and a separate bound document copying apparatus. The latching mechanism is devised which will secure together both the document handling device with the bound document copying apparatus so as to be movable as a unit relative to an exposure platen of the reproduction system, or to permit only the document handling device to be so moved.

Other examples of prior art safety latching mechanisms are disclosed in the following references: U.S. Pat. No. 6,347,819 issued February 2002 and entitled “Safety latching mechanism” discloses a latching assembly for securing a gate having a bolt extending therefrom. The latching assembly is provided with a housing and a bolt retaining member pivotally connected to the housing. The bolt retaining member has a retaining portion. The bolt retaining member has open and closed positions with the bolt retaining member being biased in the closed position. The latching assembly is further provided with a trigger connected to the housing. The trigger has locked and unlocked positions with the trigger being biased in the locked position. The trigger has a contact portion sized and configured to contact a bolt when the trigger mechanism is in the locked position. The trigger further has a locking portion sized and configured to engage the bolt retaining member when the bolt retaining member is in the open position and the trigger is in the locked position. The retaining portion and the contact portion are cooperatively sized and configured to retain a bolt therebetween when the bolt retaining member is in the closed position and the trigger is in the unlocked position.

U.S. Pat. No. 5,470,115 issued Nov. 28, 1995 and entitled “Recessed three-point latching mechanism and method for a storage locker” discloses a recessed three-point latching mechanism and method for a storage locker and a locker incorporating the same that utilizes a dead bolt system employing a pair of rotary actuated lock rods for engaging the top and bottom of the locker door opening in conjunction with a center latch engaging the door jamb. A lever, which may include a finger grip, is utilized for simultaneously unlocking the lock rods and unlatching the center latch and is accessible within a recessed cup for safety and security. The latching mechanism and method may also include a cam to hold the latching mechanism in a door open position until the door is closed to prevent damage to the locker face by the otherwise extended lock rods. The latching mechanism and method is compatible with either padlocks or a built-in lock secured within the recessed cup.

U.S. Pat. No. 5,449,298 issued Sep. 12, 1995 and entitled “Latching system for intermatable connectors” discloses a latching system for a pair of intermatable electrical connectors, such as a plug and receptacle, which incorporates a mechanism for unlatching same by the application of a maximum predetermined separating force, such as may be the result of an accident, to the plug and receptacle. The system comprises a first electrical connector having a pair of flexible arms projecting axially therefrom, where the free ends of the arms include slot means for engaging complementary arms within the second electrical connector. The second electrical connector includes a forward ramp surface against which the flexible arms initially ride to effect mating of the connectors, a rearward surface slightly angled, i.e. on the order of about 4 degree to 10 degree, from a base toward the ramp surface, and a metal spring arm mounted within the second electrical connector in close proximity to the base of the rearward surface. In the mated condition the spring arm engages the slot means. While a manually operated mechanism is provided to effect unmating, a safety system is included to prevent damage due to forces being applied thereto. For example, to effect unmating a maximum predetermined separating force may be applied therebetween causing the spring arm to flex to a position near the rearward surface at a critical release angle to thereby release the free end from its respective spring arm.

U.S. Pat. No. 4,385,423 issued May 31, 1983 and entitled “Over-center latching coupling” discloses an over-center latching device for coupling two members by the operation of a handle with the use of one hand. The device has a rod having a T at one end for engaging a hook, the other end of the rod being pivotally engaged intermediate the ends of the handle. One end of the handle is pivotally engaged on a support member adjacent and spaced from the pivot point of the rod. The other end of the handle is adapted to be gripped by the operator for completing the latching and unlatching operation. The support member which is adapted to be secured to a fixed member has a concave cam surface facing the pivoted end of the rod. The pivoted end of the rod has a leaf spring extending therefrom toward the concave cam surface. To engage the latch, the operator grips the handle and rotates it on its pivot so that the leaf spring is moved into engagement with the end of the cam surface. By the contact of the spring on the cam surface the rod is rotated so that the T-bar is moved toward the hook and as the spring is continued to be rotated on the cam the T-bar is rotated into latching engagement with the hook and the center of the rod pivot is moved over the center of the handle pivot to securely latch the rod and hook together to complete the coupling operation. A safety lock is also provided to maintain the coupling in the latched engagement.

In accordance with the present disclosure, there is provided a gang safety latching mechanism that includes (a) a torsion spring and bracket device having (i) a torsion spring subassembly (ii) a first bracket on the torsion spring subassembly having a first free position and a first loaded position, and (iii) a second bracket on the torsion spring subassembly having a second free position and a second loaded position; (b) an interference assembly defining a receiving area and including (i) an opening for passage of an end portion of the torsion spring and bracket device into and out of the receiving area, (ii) a knocker member for contacting the first bracket and (iii) a catch lip for trapping the second bracket within the receiving area; and (c) a gang locking member for locking the second bracket to the first bracket, thereby preventing unsafe separate simultaneous movement of the second movable and the first movable module relative to the main machine body.

While the present invention will be described in connection with a preferred embodiment thereof, it will be understood that it is not intended to limit the invention to that embodiment. On the contrary, it is intended to cover all alternatives, modifications, and equivalents as may be included within the spirit and scope of the invention as defined by the appended claims.

Referring nowFIG. 1, it schematically illustrates a sheet-documents producing machine such as an electrostatographic reproduction machine8which generally employs a photoconductive belt10mounted on a belt support module90. Preferably, the photoconductive belt10is made from a photoconductive material coated on a ground layer which, in turn, is coated on an anti-curl backing layer. Belt10moves in the direction of arrow13to advance successive portions sequentially through the various processing stations disposed about the path of movement thereof. Belt10is entrained as a closed loop11about stripping roll14, drive roll16, and idler roll21.

Initially, a portion of the photoconductive belt surface passes through charging station AA. At charging station AA, a corona generating device indicated generally by the reference numeral22charges the photoconductive belt10to a relatively high, substantially uniform potential. As also shownFIGS. 1-4, the machine8includes a controller or electronic control subsystem (ESS), indicated generally be reference numeral29which is preferably a self-contained, dedicated mini-computer having a central processor unit (CPU), electronic storage, and a display or user interface (UI). The ESS29, with the help of sensors and connections, can read, capture, prepare and process image data and machine status information. As such, it is the main control system for components and other subsystems of the machine8including the closed loop belt tensioning mechanism200of the present invention.

Referring again toFIG. 1, at an exposure station BB, the controller or electronic subsystem (ESS),29, receives the image signals from RIS28representing the desired output image and processes these signals to convert them to a continuous tone or gray scale rendition of the image which is transmitted to a modulated output generator, for example the raster output scanner (ROS), indicated generally by reference numeral30. The image signals transmitted to ESS29may originate from RIS28as described above or from a computer, thereby enabling the machine8to serve as a remotely located printer for one or more computers. Alternatively, the printer may serve as a dedicated printer for a high-speed computer. The signals from ESS29, corresponding to the continuous tone image desired to be reproduced by the reproduction machine, are transmitted to ROS30.

The controller29is preferably a programmable microprocessor which can be programmed to provide various controls including for example a comparison count of the copy sheets, the number of documents being recirculated, the number of copy sheets selected by the operator, time delays, jam corrections, for example. The control of all of the exemplary systems heretofore described may be accomplished by conventional control switch inputs from the machine8consoles selected by the operator. Conventional sheet path sensors or switches may be utilized to keep track of the position of the document and the copy sheets.

ROS30includes a laser with rotating polygon mirror blocks. Preferably a nine-facet polygon is used. The ROS30illuminates the charged portion on the surface of photoconductive belt10at a resolution of about 300 or more pixels per inch. The ROS will expose the photoconductive belt10to record an electrostatic latent image thereon corresponding to the continuous tone image received from ESS29. As an alternative, ROS30may employ a linear array of light emitting diodes (LEDs) arranged to illuminate the charged portion of photoconductive belt10on a raster-by-raster basis.

After the electrostatic latent image has been recorded on photoconductive surface12, belt10advances the latent image to a development station CC, which includes four developer units containing cmyk color toners, in the form of liquid or dry particles, is electrostatically attracted to the latent image using commonly known techniques. The latent image attracts toner particles from the carrier granules forming a toner powder image thereon. As successive electrostatic latent images are developed, toner particles are depleted from the developer material. A toner particle dispenser, indicated generally by the reference numeral44, dispenses toner particles into developer housing46of developer unit38.

With continued reference toFIG. 1, after the electrostatic latent image is developed, the toner powder image present on belt10advances to transfer station DD. A print sheet48is advanced to the transfer station DD, by a sheet feeding apparatus50. Preferably, sheet feeding apparatus50includes a feed roll52contacting the uppermost sheet of stack54. Feed roll52rotates to advance the uppermost sheet from stack54to vertical transport56. Vertical transport56directs the advancing sheet48of support material into registration transport57past image transfer station DD to receive an image from photoreceptor belt10in a timed sequence so that the toner powder image formed thereon contacts the advancing sheet48at transfer station DD. Transfer station DD includes a corona-generating device58, which sprays ions onto the backside of sheet48. This attracts the toner powder image from photoconductive surface12to sheet48. After transfer, sheet48continues to move in the direction of arrow60by way of belt transport62, which advances sheet48to fusing station FF.

Fusing station FF includes a fuser assembly indicated generally by the reference numeral70which permanently affixes the transferred toner power image to the copy sheet. Preferably, fuser assembly70includes a heated fuser roller72and a pressure roller74with the powder image on the copy sheet contacting fuser roller72. The pressure roller is crammed against the fuser roller to provide the necessary pressure to fix the toner powder image to the copy sheet. The fuser roll is internally heated by a quartz lamp (not shown). Release agent, stored in a reservoir (not shown), is pumped to a metering roll (not shown). A trim blade (not shown) trims off the excess release agent. The release agent transfers to a donor roll (not shown) and then to the fuser roll72.

The sheet then passes through fuser70where the image is permanently fixed or fused to the sheet. After passing through fuser70, a gate either allows the sheet to move directly via output17to a finisher or stacker, or deflects the sheet into the duplex path100, specifically, first into single sheet inverter82here. That is, if the second sheet is either a simplex sheet, or a completed duplexed sheet having both side one and side two images formed thereon, the sheet will be conveyed via gate88directly to output17. However, if the sheet is being duplexed and is then only printed with a side one image, the gate88will be positioned to deflect that sheet into the inverter82and into the duplex loop path100, where that sheet will be inverted and then fed to acceleration nip102and belt transports110, for recirculation back through transfer station DD and fuser70for receiving and permanently fixing the side two image to the backside of that duplex sheet, before it exits via exit path17.

After the print sheet is separated from photoconductive surface12of belt10, the residual toner/developer and paper fiber particles adhering to photoconductive surface12are removed therefrom at cleaning station EE. Cleaning station EE includes a rotatably mounted fibrous brush device87in contact with photoconductive surface12to disturb and remove paper fibers and a cleaning blade to remove the non-transferred toner particles. The blade may be configured in either a wiper or doctor position depending on the application. Subsequent to cleaning, a discharge lamp (not shown) floods photoconductive surface12with light to dissipate any residual electrostatic charge remaining thereon prior to the charging thereof for the next successive imaging cycle.

Referring now toFIGS. 1 and 2, the sheet-documents producing machine8as shown includes plural sheet-copy documents finishing devices200and300. Only two such devices200and300are shown, but it is understood that any plural number thereof may be used. As shown, the sheet-copy document finishing device200is for example a compiler210that includes a compiler housing212for receiving and compiling a stack214of sheets, and a compiler input transport module220for transporting sheets from the Image Output terminal8into the compiler housing212. The compiler input transport module220includes sheet transport rolls222, and is mounted on the compiler housing212for movement, (e.g. pivotable movement), relative to the compiler housing212. Such movement could equally be up and down translational movement relative to the compiler housing212.

For transporting sheets past the compiler210to the next sheet finishing device300, the machine9ofFIG. 2includes a bypass transport module230, that as shown, is mounted (fro example to and) on top of the compiler input transport module220for movement, (e.g. pivotable movement), relative to the compiler input transport module220and to the compiler housing212. The bypass transport module230also includes sheet transport rolls232, and ordinarily could be movable separately and simultaneously with the compiler input transport module220, relative to the compiler housing212. Such movement could equally be up and down translational movement relative to the compiler input transport module220.

Thus the image producing machine9can be seen to include (a) a main machine body or image output terminal8having image forming and transfer components including a photoreceptor10, sheet supply modules50,51, and a fusing apparatus70; (b) several other modules200,300, including a reference module such as the compiler housing212, and at least two movable modules such as the compiler input transport module220and bypass transport module230that are co-assembled to the reference module (compiler housing212) for movement relative to each other and to the reference module (compiler housing212). In order to prevent the compiler input transport module220and bypass transport module230from moving simultaneously but separately in an unsafe manner, the sheet-copy document finishing device200includes the gang safety latching mechanism400of the present disclosure.

Referring now toFIGS. 3-7, the gang safety latching mechanism400and its use are illustrated in detail. As shown, the gang safety latching mechanism400comprises (a) a torsion spring and bracket device410including (i) a torsion spring subassembly412for attaching to a first movable module, for example the compiler input transport module220, of the at least two co-assembled movable modules, (ii) a first bracket420mounted onto the torsion spring subassembly412, having a first free position FP1and a first loaded position LP1, and being movable between the first free position and the first loaded position, and (iii) a second bracket440mounted onto the torsion spring subassembly412, having a second free position FP2and a second loaded position LP2, and being movable between the second free position and the second loaded position.

The gang safety latching mechanism400also includes an interference assembly450defining a receiving area452. The interference assembly450is locatable on the reference module or compiler housing212and includes (i) an opening454for passage of an end portion414of the torsion spring and bracket device410into and out of the receiving area452, (ii) a knocker member456for contacting the first bracket420when the end portion414(of the torsion spring and bracket device410, is passed through the opening454; and (iii) a catch lip458for trapping the second bracket440by means of a shoulder portion442thereof, within the receiving area452. Although the interference assembly450is described here as a unitary assembly, it could be comprised of a first member acting as the knocker member456and of a second member acting as the catch lip458. In fact the first member and second member as such could be portions or parts of the reference module or body212that are arranged or located apart to create an effective gap or opening454between them, into an open space between them that is sufficient to receive the lower or end portion414of the torsion spring and bracket device410.

The gang safety latching mechanism400further includes a gang locking member460, for example an attachable pin, locatable on a second movable module, such as the bypass transport module230of the at least two co-assembled movable modules, for locking the second bracket440to the first bracket420, thereby gang locking the second movable module or bypass transport module230to the first movable module or compiler input transport module220, and thereby preventing unsafe separate simultaneous movement of the second movable and the first movable module relative to the reference module.

Specifically, the first bracket includes a first body422, a first first end424including a first finger428, and a first second end426mounted to the torsion spring subassembly412by means a pivot shaft413. The second bracket440similarly includes a second body441, a second first end444including a second finger448, and a second second end446also mounted to the torsion spring subassembly412by means of the pivot shaft413. On the torsion spring and bracket device410(as shown inFIG. 5), a first direction D1of movement of the first bracket420from the first loaded position LP1to the first free position FP1is opposite to a second direction D2of movement of the second bracket440from the second loaded position LP2to the second free position FP2. As shown inFIGS. 6 and 7, the first first end424of the first bracket420and the second first end444of the second bracket440of the torsion spring and bracket device410have an open position M1away from each other and a closed or locking position M2proximate each other.

The knocker member456of the interference assembly450is located on the reference module212for contacting and moving the first bracket420(against a force of the torsion spring) from the first free position FP1to the first loaded position LP1when the end portion414of the torsion spring and bracket device410is being passed through the opening454into the receiving area452of the interference assembly. The catch lip458of the interference assembly450is located for trapping the second bracket440(by means of the shoulder portion;442of the second bracket) within the receiving area452when the second bracket440is within the receiving area and in the second free position FP2.

The gang locking member460has (i) a first position LD against the second finger448of the second bracket440that corresponds to a closed position of the second movable module230relative to the first movable module220, and (ii) a second position LU away from the second finger448of the second bracket440. The second position LU corresponds to an open position of the second movable module230relative to the first movable module220.

The torsion spring subassembly412includes an attaching member415for attaching the torsion spring and bracket device410to the first movable module220. The torsion spring subassembly412also includes a torsion spring416that is mounted around the pivot shaft413, and that has a first end417for moving the first bracket420from the first loaded position LP1to the first free position FP1, and a second end418for moving the second bracket440from the second loaded position LP2to the second free position FP2.

Referring now toFIGS. 2-7, the attaching member415of the torsion spring subassembly412(of the torsion spring and bracket device410) is attached to the compiler input transport module220(the compiler input transport module here in general is the first module or first body of the plural co-assembled movable modules or bodies). The interference assembly450is mounted to the reference module/body or compiler housing212at a first aligned location below the torsion spring and bracket device410for interacting with the lower or end portion414of the torsion spring and bracket device410as it passes into and out of the receiving area452thereof, as the compiler input transport/first module or body220opens and closes relative to the reference module/body or compiler housing212. The gang locking member460is then attached to the bypass transport module230(in general the bypass transport module here is a second movable module or body), and at a second aligned location above the torsion spring and bracket device410for interacting with the first and second fingers428,448of the first and second brackets420,440, as the bypass transport module230is opened and closed relative to the compiler input transport module220.

In operation, when both the first and second co-assembled movable modules, for example the compiler input transport module220and the bypass transport module230are closed as shown inFIG. 2, the gang safety latching mechanism400will assume its second module-releasing posture as shown inFIG. 5. As shown, the end or lower portion414will be within the receiving area452of the interference assembly450, the knocker member456would have contacted and moved the first bracket420into the first loaded position LP1, and the gang locking member460will have moved and be holding the second bracket440in the second loaded position LP2. In this posture, the first finger428of the first bracket420is in the open position M1relative to the second finger448of the second bracket440. As such, the gang locking member460, and hence the second module230to which it is attached, is free to be moved away from the second finger448without running into the first finger428.

Note also (as shown inFIG. 5) that by the second bracket440being in the second loaded position LP2, the shoulder portion442thereof (within the receiving area452of the interference assembly450) is clear of the catch lip458. An operator can choose at this point whether to open only the second module230(by moving the gang locking member460away from the second finger448) or to keep the first module closed and open the first module220(by moving the lower portion414of the torsion spring and bracket device410out of the receiving area452).

If the operator chooses to open only the second module230(by moving the gang locking member460away from the second finger448) as illustrated inFIGS. 3 and 6, then the second finger448of the second bracket440will be released from the second loaded position LP2and immediately move into the second free position FP2even while the lower portion414of the torsion spring and bracket device410is still within the receiving area452of the interference assembly. As such, the shoulder portion442thereof is now no longer clear of the catch lip458, thereby trapping shoulder portion442and the entire torsion spring and bracket device410within the receiving area. This prevents the first module220from being opened when the second module230is opened as here by the operator's choosing.

If however the operator chooses to open the first module220(by moving the lower portion414of the torsion spring and bracket device410out of the receiving area452) as illustrated inFIGS. 4 and 7, then the gang locking member460must be down (position LD) against the second finger448, thus holding the second bracket in the second loaded position FP2so that its shoulder portion442is clear of the catch lip458of the interference assembly450. At this point, the operator can proceed to open the first module220relative to the reference module212, thus pulling the lower or end portion414of the torsion spring and bracket device410out of the receiving area452of the interference assembly450. Pulling the lower or end portion414as such out of the receiving area immediately frees the first bracket420of the holding power of the knocker member456of the interference assembly450, thus allowing it to immediately move from the first loaded position LP1into the first free position FP1. This brings a claw portion429of the first finger428into the locking position M2, locking the gang locking member460between the first finger428and second finger448. This thus gang locks the second module230to the first module220, as the first module220is being opened as here according to the operator's choosing.

As such, the gang safety latching mechanism400effectively prevents the first module220and the second module230(here the compiler input transport module, and the bypass transport module) or in general any co-assembled movable multiple layered modules or paper path transports, from being opened simultaneously and separately. As we have seen, only one transport or module can be opened at any one time.

The gang safety latching mechanism400is a compact and reliable dual action mechanism that interacts and reacts mechanically with (a) the bypass; transport or second module or second body441, (b) the compiler input transport or first module or first body422and (c) the compiler housing or reference module or body212to accomplish the above sequence of safe control over movement or opening and closing of the co-assembled movable modules wherein one must be closed before the other is opened. This is all accomplished mechanically with no sensors or electrical/software parts required to operate this latching mechanism.

As can be seen, there has been provided a gang safety latching mechanism that includes (a) a torsion spring and bracket device having (i) a torsion spring subassembly (ii) a first bracket on the torsion spring subassembly having a first free position and a first loaded position, and (iii) a second bracket on the torsion spring subassembly having a second free position and a second loaded position; (b) an interference assembly defining a receiving area and including (i) an opening for passage of an end portion of the torsion spring and bracket device into and out of the receiving area, (ii) a knocker member for contacting the first bracket and (iii) a catch lip for trapping the second bracket within the receiving area; and (c) a gang locking member for locking the second bracket to the first bracket, thereby preventing unsafe separate simultaneous movement of the second movable and the first movable module relative to the main machine body.

It will be appreciated that various of the above-disclosed and other features and functions of this embodiment, or alternatives thereof, may be desirably combined into other different systems or applications. Also that 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.