Fluid control devices such as fluidic dies can control movement and ejection of fluid. Such fluidic dies may include fluid actuators that may be actuated to cause displacement of fluid. Some example fluidic dies may include printheads, where fluids used by the printheads can include ink or other types of fluids.
Some implementations of the present disclosure are described with respect to the following figures.
Throughout the drawings, identical reference numbers designate similar, but not necessarily identical, elements. The figures are not necessarily to scale, and the size of some parts may be exaggerated to more clearly illustrate the example shown. Moreover, the drawings provide examples and/or implementations consistent with the description; however, the description is not limited to the examples and/or implementations provided in the drawings.
In the present disclosure, use of the term “a,” “an”, or “the” is intended to include the plural forms as well, unless the context clearly indicates otherwise. Also, the term “includes,” “including,” “comprises,” “comprising,” “have,” or “having” when used in this disclosure specifies the presence of the stated elements, but do not preclude the presence or addition of other elements.
A fluid control device can include multiple fluid actuators that when actuated cause displacement of fluid. For example, the fluid control device can control ejection of a fluid from an orifice of the fluid control device towards a target. In such examples, the fluid control device can be referred to as a fluid ejection device that is able to control ejection of fluids. In some examples, fluid ejection devices can include printheads that are used in two-dimensional (2D) or three-dimensional (3D) printing. In 2D printing, a printhead can eject ink or other printing fluid directed to a target substrate (e.g., paper, plastic, etc.) to print a pattern onto the target substrate. In 3D printing, a printhead can eject a fluid used to form a 3D target object. A 3D printing system can form the 3D target object by depositing successive layers of build material. Printing fluids dispensed from the 3D printing system can include ink, as well as fluids used to fuse powders of a layer of build material, detail a layer of build material (such as by defining edges or shapes of the layer of build material), and so forth.
In other examples, a fluid control device can include pumps that control fluid flows through respective fluid channels. More generally, a fluid control device can be used in either a printing application or a non-printing application. Examples of fluid control devices used in non-printing applications include fluid control devices in fluid sensing systems, medical systems, vehicles, fluid flow control systems, and so forth. In a printing application, a fluid control device, such as a fluidic die, can be mounted onto a print cartridge, where the print cartridge can be removably mounted in a print system. For example, the fluidic die can be a printhead die that is mounted to the print cartridge. In another example of a printing application, fluid control devices (such as fluidic dies) can be mounted onto a print bar that spans the width of a target medium (e.g., a paper medium or medium of another material) onto which printing fluids are to be dispensed.
A fluid control device can include multiple fluid actuators that when actuated causes displacement of fluid. As used here, displacement of fluid can refer to movement of fluid within a fluid channel inside the fluid control device, or to ejection of fluid from inside a fluid chamber of the fluid control device through an orifice to a region outside the fluid control device.
An activation signal (also referred to as a “fire pulse”) can be used to actuate the fluid actuators. The activation signal can be asserted to an active state for a specified time duration (the specified time duration of the active state of the activation signal is the pulse width of the activation signal). When the activation signal is asserted to the active state, selected fluid actuators are actuated, where the selection of fluid actuators is based on input control information as discussed further below. While the activation signal is deasserted to an inactive state, fluid actuators cannot be actuated.
The multiple fluid actuators of a fluid control device can be partitioned into “primitives” (also referred to as “firing primitives”), where a primitive includes a group of a certain number of fluid actuators. A number of fluid actuators included in a primitive can be referred to as a size of the primitive. Traditionally, primitives of a fluid control device are configured using hardware circuitry, and thus a size of the primitives used in the fluid control device is fixed. To reduce a peak current when actuating fluid actuators in the primitives, and to minimize power supply transients associated with simultaneous actuation of multiple fluid actuators, a delay can be used to delay the activation signal so that the actuation of fluid actuators between the primitives is correspondingly delayed. In fixed-size primitives, one delay element is provided per primitive. Each fluid actuator of a primitive can be uniquely addressed to select the fluid actuator.
In accordance with some implementations of the present disclosure, variable-sized primitives can be used in a fluid control device. For a first actuation event (or a first set of actuation events), primitives of a first primitive size can be used, while for a second actuation event (or second set of actuation events), primitives of a second primitive size (different from the first primitive size) can be used. Varying sizes of primitives can be implemented by using different mask data patterns in a mask register of the fluid control device. A first mask data pattern can specify the first primitive size, while a second mask data pattern can specify the second primitive size.
In arrangements that allow variable-sized primitives according to some implementations of the present disclosure, each fluid actuator can be individually associated with a delay element for delaying an activation signal. The delay elements are daisy chained one to another, so are arranged in series. A delay element is associated with each individual fluid actuator because, in response to a given actuation event, just a respective subset of fluid actuators (where the subset can include just one fluid actuator or some other number of fluid actuators) in each virtual primitive is actuated. For another actuation event, another subset of fluid actuators in each virtual primitive is actuated.
An actuation event can refer to concurrent actuation of fluid actuators of a fluid control device to cause corresponding fluid displacement.
To avoid excessive delays from being applied to the activation signal, the delay elements individually associated with the fluid actuators can be selectively activated and deactivated, based on a determination of whether or not each fluid actuator is to be actuated. A delay element for an active fluid actuator (a fluid actuator to be actuated) can be activated to delay the activation signal, while a delay element for an inactive fluid actuator (a fluid actuator that is not to be actuated) is deactivated to not delay the activation signal. Note that if the activation signal is subjected to delays of all of the delay elements (arranged in series) that are associated with individual fluid actuators, then a large delay can be imposed on the activation signal. Excessive delay of the activation signal can reduce the speed at which fluid displacement operations (e.g., printing operations) can be performed.
The fluidic die 100 includes multiple fluid actuators 102. The fluid actuators 102 can be arranged as an array of fluid actuators, which can be a 1-dimensional (1D) array of fluid actuators or a two-dimensional (2D) array of fluid actuators. In other examples, the fluid actuators 102 can be arranged in a different pattern.
Although
In some examples, a fluid actuator 102 can be disposed in a nozzle of the fluidic die 100, where the nozzle may include a fluid chamber and a nozzle orifice in addition to the fluid actuator. The fluid actuator may be actuated such that displacement of fluid in the fluid chamber may cause ejection of a fluid drop through the nozzle orifice. Accordingly, a fluid actuator disposed in a nozzle may be referred to as a fluid ejector.
A fluid actuator 102 can include an actuator that includes a piezoelectric membrane, an actuator that includes a thermal resistor, an actuator that includes an electrostatic membrane, an actuator that includes a mechanical/impact driven membrane, an actuator that includes a magneto-strictive drive actuator, or other such elements that may cause displacement of fluid responsive to electrical actuation or actuation resulting from another type of input stimulus.
In some examples, the fluidic die 100 can include microfluidic channels. Microfluidic channels may be formed by performing etching, microfabrication (e.g., photolithography), micromachining processes, or any combination thereof in a substrate of the fluidic die 100. A microfluidic channel may include a fluid channel of specified small size (e.g., of nanometer sized scale, micrometer sized scale, millimeter sized scale, etc.) to facilitate conveyance of small volumes of fluid (e.g., picoliter scale, nanoliter scale, microliter scale, milliliter scale, etc.).
Some example substrates of fluidic dies can include silicon based substrates, glass based substrates, gallium arsenide based substrates, and/or other such suitable types of substrates for micro fabricated devices and structures. Accordingly, microfluidic channels, chambers, orifices, and/or other such features may be defined by surfaces fabricated in the substrate of the fluidic die 100. The fluid actuators 102 (or a subset of the fluid actuators 102) can be disposed in respective microfluidic channels. In such examples, actuation of a fluid actuator 102 disposed in a microfluidic channel can generate fluid displacement in the microfluidic channel. Accordingly, a fluid actuator 102 disposed in a microfluidic channel may be referred to as a fluid pump.
The fluidic die 100 includes an actuation controller 104. A “controller” as used herein can refer to any hardware processing circuit, which can include logic circuitry, a microprocessor, a core of a multi-core microprocessor, a microcontroller, a programmable gate array, a programmable integrated circuit device, or any other hardware processing circuit. In further examples, a controller can include a combination of a hardware processing circuit and machine-readable instructions executable on the hardware processing circuit.
The actuation controller 104 receives input control information 106 relating to controlling an actuation of the fluid actuators 102. Based on the input control information 106, the actuation controller 104 determines which of the fluid actuators 102 are to be actuated. Note that not all of the fluid actuators 102 would be actuated in response to the input control information 106 in some examples.
As explained further below, the input control information 106 is based on the content of various registers.
The actuation controller 104 produces various Activate outputs. More specifically, the actuation controller 104 produces N (N≥2) Activate outputs for N fluid actuators 102: Activate[0 . . . N−1]. An Activate[i] output, i=0 to N−1, is asserted to an active state (e.g., “1”) in response to the input control information 106 selecting a corresponding fluid actuator i for actuation. On the other hand, the actuation controller 104 deasserts the Activate[i] output to an inactive state in response to the actuation controller 104 determining, based on the input control information 106, that the respective fluid actuator i is not to be actuated.
Each Activate[i] output can be in the form of a signal or any other indication (e.g., a message, an information field, etc.) that can be used to control actuation of the respective fluid actuator i.
As depicted in
Each of the multiple delay elements 108 is associated with a respective fluid actuator 102.
The instance of the activation signal that is received at the input of the chain of delay elements 108 is referred to as activation signal[0]. Activation signal[0] is provided to the input of a first delay element 108, which can selectively delay (or not) activation signal[0]. The output of the first delay element 108 is another activation signal instance, referred to as activation signal[1]. Further down the chain of delay elements 108, a further activation signal instance, activation signal[j], is provided to the input of a further delay element 108, which can selectively delay (or not) activation signal[j]. The output of the further delay element 108 is another activation signal instance, activation signal[j+1].
Each fluid actuator i receives the corresponding Activate[i] output from the actuation controller 104 and a respective instance of the activation signal (activation signal[i]) from the chain of delay elements 108. The combination of the respective activation signal[i] (being at an active state) and the respective Activate[i] output (being asserted to an active state) causes an activation circuit in the respective fluid actuator i to actuate fluid actuator i.
Each Activate[i] output from the actuation controller 104 also controls the activation or deactivation of a respective delay element 108. Delay element i is activated in response to the corresponding Activate[i] output being asserted to an active state. Activated delay element i delays a corresponding activation signal instance, activation signal[i], by a target delay amount (as provided by a delay circuit in delay element i), and outputs the next activation signal instance, activation signal[i+1]. In contrast, a delay element i is deactivated (such that delay element i does not delay activation signal[i] by the target delay amount) in response to the Activate[i] output being deasserted to an inactive state.
Thus, when a given fluid actuator 102 is not to be activated, then the respective delay element 108 remains inactive, such that the deactivated delay element 108 does not delay the activation signal 110 by the target delay amount of a delay element.
Each activation signal instance produced in the chain of delay elements 108 can be delayed a different amount relative to the input activation signal 110 (activation signal[0]) depending on how many delay elements upstream in the chain of delay elements 108 were active.
More generally, the actuation controller 104 is to, in response to determining that a given fluid actuator 102 is to be actuated, activate a respective delay element associated with the given fluid actuator 102, where the delay element is to delay an activation signal instance propagated to selected fluid actuators of multiple fluid activators in response to an actuation event.
Further, the actuation controller 104 determines, based on the input control information 106, a first subset of the fluid actuators 102 that are to be actuated, and a second subset of the fluid actuators 102 that are not to be actuated, and activates delay elements 108 associated with the first subset of the fluid actuators 102 to delay the activation signal 110, and deactivates delay elements associated with second subset of fluid actuators 102
The output of the delay circuit 202 is provided to the “1” input of a multiplexer 204, while activation signal[i] is provided to the “0” input of the multiplexer 204. A “multiplexer” can refer to any logic that is able to select from among multiple inputs, where the selected input is provided to the output of the multiplexer.
Selection of the “0” input or the “1” input of the multiplexer 204 is controlled by an Activate[i] output from the actuation controller 104. The Activate[i] output is provided to the select control input of the multiplexer 204. If the Activate[i] output is set to an inactive state (e.g., “0”), then the “0” input of the multiplexer 204 is selected, and activation signal[i] is propagated through the multiplexer 204 to the output of the multiplexer 204 as output activation signal[i+1]. Selecting the “0” input of the multiplexer 204 effectively bypasses the delay circuit 202, such that activation signal[i] is not delayed by the target delay amount of the delay circuit 202.
On the other hand, if the Activate[i] output is asserted to an active state (e.g., “1”), then the “1” input of the multiplexer 204 is selected, and the output of the delay circuit 202 is selected and propagated through the multiplexer 204 to the output of the multiplexer 204 as output activation signal[i+1].
In other examples, activation signal[i] can be connected to the “1” input of the multiplexer 204, while the output of the delay circuit 202 is connected to the “0” input of the multiplexer 204. The Activate[i] input to the select control input of the multiplexer 204 would be inverted in such examples. In yet further examples, different logic for selectively delaying or not activation signal[i] can be used in the delay element 108.
In the example of
It is assumed in the example of
In
An AND function receives multiple inputs, and produces an active output if all of the multiple inputs are at the active state. Although AND functions are depicted in
The actuation data register 404 can store actuation data that indicates each fluid actuator to actuate for a set of actuation events. Actuating a fluid actuator refers to causing operation of the fluid actuator to perform fluid displacement in the fluidic die 100. As noted above, an actuation event can refer to concurrent actuation of fluid actuators of the fluidic die 100 to cause fluid displacement. An actuation event can be responsive to a command issued to the fluidic die, or a command issued in the fluidic die, to cause fluid displacement to occur. A “set of actuation events” can refer to any sequence or collection of events that can cause respective different groups of fluid actuators 102 to actuate.
Assuming there are N (N≥2) fluid actuators 102, the actuation data stored in the actuation data register 404 includes N values that correspond to the N fluid actuators 102. In some examples, each value (represented as “A” in
The mask register 406 can store a mask data pattern that indicates a subset of the fluid actuators 102 that is (are) enabled for actuation for a respective actuation event or the set of actuation events. Enabling a fluid actuator for actuation can refer to allowing the fluid actuator to be activated in response to a value of the actuation data in the actuation data register 404 specifying that the fluid actuator is to be actuated.
A mask data pattern stored in the mask register 406 can have N values that correspond to N fluid actuators 102. Each value (represented as “M” in
If a value of a mask data pattern indicates that a particular fluid actuator is not enabled for actuation, then the particular fluid actuator will not be actuated even though the actuation data stored in the actuation data register 404 specifies that the particular fluid actuator 102 should be actuated. On the other hand, if a mask data pattern specifies that the particular fluid actuator is enabled for actuation, the particular fluid actuator is actuated only if the actuation data stored in the actuation data register 404 specifies that the particular fluid actuator is to be actuated. More specifically, a given fluid actuator 102 is to be actuated in response to both a value (“A”) of the actuation data register 404 specifying that the given fluid actuator 102 is to be actuated, and a corresponding value (“M”) of the mask data pattern enabling actuation of the given fluid actuator 102.
In the example of
In some examples, different mask data patterns can be written to the mask register 406. One example use case of writing different mask data patterns to the mask register 406 is to set a different primitive size. For example, for a first set of actuation events, a first mask data pattern can be written to the mask register 406 to set a first primitive size, for a second set of actuation events, a second mask data pattern can be written to the mask register 406 to set a second primitive size, and so forth.
In other examples, instead of using just one mask register 406, multiple mask registers can be included in the fluidic die 400, where the multiple mask registers can store different mask patterns. A multiplexer (not shown) can be provided to select from among the multiple mask registers to select the mask data pattern to use.
The mask data pattern in the mask register 406 in the fluidic die 400 of
The shifting operation of the mask data pattern in the mask register 406 can be controlled by a mask register controller 702, as shown in
For actuation event 1, as shown in
For actuation event 3, as shown in
More generally, the mask register controller 702 is to shift the mask data pattern in the mask register 406 in response to each actuation event of a set of actuation events, where the shifting is to cause enabling of a different set of fluid actuators for each successive actuation event. The shifting of the mask data pattern in the mask register 406 can include a circular shift (as shown in
The fluid control system 800 further includes a fluidic die 804, which includes multiple fluid actuators 102, multiple delay elements 108 associated with the fluid actuators 102, where the delay elements if activated are to delay an activation signal 110.
The fluidic die 804 further includes a register 806 (e.g., the actuation data register 404 and/or the mask register 406 of
As noted above, in some examples, certain logic (such as the various controllers) can be implemented as either a hardware processing circuit or as a combination of a hardware processing circuit and machine-readable instructions (software or firmware) executable on the hardware processing circuit.
In examples where machine-readable instructions are employed, the machine-readable instructions can be stored in a non-transitory machine-readable or computer-readable storage medium.
The storage medium can include any or some combination of the following: a semiconductor memory device such as a dynamic or static random access memory (a DRAM or SRAM), an erasable and programmable read-only memory (EPROM), an electrically erasable and programmable read-only memory (EEPROM) and flash memory; a magnetic disk such as a fixed, floppy and removable disk; another magnetic medium including tape; an optical medium such as a compact disk (CD) or a digital video disk (DVD); or another type of storage device. Note that the instructions discussed above can be provided on one computer-readable or machine-readable storage medium, or alternatively, can be provided on multiple computer-readable or machine-readable storage media distributed in a large system having possibly plural nodes. Such computer-readable or machine-readable storage medium or media is (are) considered to be part of an article (or article of manufacture). An article or article of manufacture can refer to any manufactured single component or multiple components. The storage medium or media can be located either in the machine running the machine-readable instructions, or located at a remote site from which machine-readable instructions can be downloaded over a network for execution.
In the foregoing description, numerous details are set forth to provide an understanding of the subject disclosed herein. However, implementations may be practiced without some of these details. Other implementations may include modifications and variations from the details discussed above. It is intended that the appended claims cover such modifications and variations.
Filing Document | Filing Date | Country | Kind |
---|---|---|---|
PCT/US2017/027560 | 4/14/2017 | WO | 00 |