Patent Application
20230252911
This disclosure relates to a Braille display. More specifically, the present disclosure relates to a Braille display with various features for preventing the ingress of contaminants.
A Braille display is a device that allows blind or low vision users to read text. These displays typically include one or more lines, with each line comprising individual tactile cells. A typical display may include 20, 40, or even 80 cells. Each cell, in turn, contains six or eight tactile pins that move up and down with respect to a surrounding Braille deck. The tactile pins can be driven by mechanical, electromechanical, piezoelectric, pneumatic, magnetic, or electromagnetic effects. When in the raised position, the pins extend above the deck and can be felt by a user. By raising certain pins and keeping others below the deck surface, individual Braille characters can be generated. A series of cells together represent a line of text. After a line has been read the user can refresh the display to allow for additional lines to be presented and read. Certain types of displays may present multiple lines of Braille text at a time. Braille displays are often combined with other hardware and software to make up an integrated unit.
Braille displays are sensitive pieces of equipment that are prone to being damaged by contaminants. These contaminants can be, for example, dust, dirt or airborne particles that gain entry into the display by way of apertures associated with the tactile pins. Braille displays can also be damaged by foods or liquids, as may occur if the user is reading the display while eating or drinking. Regardless of how it occurs, any intrusion into the Braille display can harm sensitive components, such as actuator assemblies, tactile pins, circuit boards, or associated electrical components. Because these components have especially tight tolerances, even the smallest of particles can cause serious damage. This damage may render the display unusable and require expensive repairs.
Over the years efforts have been made to protect the components associated with Braille displays. As example of one such effort is disclosed in U.S. Pat. No. 6,743,021 to Prince et al. Prince discloses a refreshable Braille display with an outer, flexible surface. More specifically, Prince discloses the use of a flexible, compliant polymer material that is stretched over the top of the housing associated with a Braille display. This flexible layer creates a continuous surface and offers environmental protection to associated electronics.
Similarly, U.S. Pat. No. 6,354,839 to Schmidt et. al. discloses a refreshable Braille display system. The display includes a single sheet of a polymer material that is stretched over top of the Braille display. This gives the display a continuous surface and protects associated microelectromechanical devices.
Although the Prince and Schmidt devices each achieve their own unique and important objectives, they both suffer from common drawbacks. Namely, both devices achieve some limited degree by environmental protection by adhering a material over top of the associated Braille dots. Doing so drastically alters the user's tactile interaction with the display. This can be a significant drawback for blind/low vision users, as often their only interaction with the display is through their fingertips. Braille dots are designed to provide users with a distinct, satisfying, and clear feel. This tactile interaction allows users to easily read the display and distinguish between various Braille characters. Displays such as Prince and Schmidt interfere with this tactile experience by interposing a material layer between the user's finger tips and the Braille dots.
What is needed, therefore, is a refreshable Braille display that protects internal components from the ingress of contaminants, while at the same time preserving the tactile feel of the Braille dots. The Braille display of the present disclosure is designed to fulfill these and other shortcomings present in the art.
This disclosure relates to various ingress protected Braille displays.
One disclosed display includes a film sheet that is positioned beneath the dot pins to prevent contaminants from damaging sensitive display components.
An advantage of this film sheet is realized by positioning it to both protect the display and secure the dot pins.
Another advantage is realized by positioning the sheet over top of an associated actuator assembly to prevent contaminants from accessing the internal components of the assembly.
Another advantage is realized by providing a plenum in the display housing and coupling the plenum to a fluid source.
This arrangement applies a source of pressurized air to the dot pin openings, which advantageously ejects any contaminants and also prevents the entry of any contaminants.
An advantage of the present disclosure is that it protects the internal components of a Braille display without sacrificing the feel of the dot pins.
Various embodiments of the invention may have none, some, or all of these advantages. Other technical advantages of the present invention will be readily apparent to one skilled in the art.
For a more complete understanding of the present disclosure and its advantages, reference is now made to the following descriptions, taken in conjunction with the accompanying drawings, in which:
Similar reference numerals refer to similar parts throughout the several views of the drawings.
The present disclosure relates to a Braille display with protection against the ingress of contaminants. In one embodiment, contaminant protection is provided by a flexible film that is secured beneath the Braille dots of the display. This film both secures the dots and prevents contaminants from coming into contact with pin actuators and other components within the display housing. In another embodiment, ingress protection is provided by fluid pressure supplied to a plenum located at the base of the dot pins. Both of these embodiments are described in greater detail hereinafter.
In the depicted embodiment, a sufficient number of dot pins (34) are included to provide for eight different refreshable Braille characters, with each individual character including eight
The dot pins (34) are slidably received within corresponding pin openings (32) formed within the Braille deck (28). Each dot pin (34) is defined by an upper end (36) and a lower base (38). The pins (34) can be raised such that the upper ends (36) of selected dot pins (34) are selectively positioned above the surface Braille deck (28). This allows the upper ends (36) to be touched, or read, by the user's finger tips. Conversely, each dot pin (32) can be selectively lowered below the surface of the Braille deck (28). In this way, individual Braille characters can be formed along the length of the Braille deck (28). The movement of the individual dot pins (34) is achieved via an actuator assembly (58) and an associated microprocessor (not shown) positioned within the lower display housing (54).
With continuing reference to
Film (42) includes upper and lower surfaces (44, 46) and a peripheral extent (48). It optionally includes a series of indentations (52), with the indentations (52) corresponding to the position and arrangement of the dot pins (34) associated with display (10). As illustrated, a portion of the peripheral extent (48) of the film (42) is secured to the upper housing (20). More specifically, film (42) can be secured via screws, fasteners, or adhesives to the underside of the Braille deck (28). In the preferred embodiment, the peripheral extent of film (42) is secured to the bottom of Braille deck (28) via a pressure sensitive adhesive. However, it is also within the scope of the present disclosure to use a larger piece of film (42) such that its peripheral extent extends beyond the Braille deck (28) and is adhesively adhered to the inner surface (22) of housing (20).
When properly positioned, the upper surface (44) of the film (42) is secured to the Braille deck (28) and contacts the lower ends (38) of the dot pins (34). By positioning film (42) in this fashion, dot pins (34) are restrained and prevented from being removed from the associated pin openings (32). This positioning also allows upper housing (20) to be removed from the lower housing (54) for servicing the device (10) without disturbing the positioning of the pins (34). Film (42) also prevents any contaminants that have entered the pin openings (32) from contacting the lower pin actuators (58) or other sensitive internal components. Importantly, this is accomplished without otherwise disrupting the user's tactile feel of the dot pins (34).
The actuator assembly (58) is illustrated in
The pneumatic ingress protection display (72) includes a housing (74) for storing an actuator assembly (76) and an associated microprocessor (78) (
With reference to
Braille deck (84) further includes opposing ends, with one of the ends (92) housing a pneumatic chamber (106). The purpose of this chamber is described below. A series of dot openings (94) are formed through the Braille deck (84) with these openings slidably receiving a series of corresponding dot pins (96). Each dot pin (96), in turn, includes an upper surface (98) that is adapted to be felt by the user and a lower base (102). Each lower base (102) is adapted to be driven by a pin actuator (80). Thus, dot pins (96) collectively correspond to, and are driven by, the pin actuators (80).
A flexible sheet (112) positioned within and secured to recess (104) within the lower surface (88) of the Braille deck (84). As in the prior embodiment, flexible sheet (112) is preferably formed from a 20 micron thin sheet of ELASTOSIL® Film. ELASTOSIL® is a silicon film manufactured by Wacker Chemie AG of Munich, Germany. However, other thin, flexible, and impermeable films may also suffice. As illustrated, film (112) is dimensioned to be received within the recess (104) within the lower surface (88) of the Braille deck (84). Film (112) is preferably secured in place via a pressure sensitive adhesive. However, other types of adhesives as well as mechanical fasteners can also be used. When properly secured, film (112) is in contact with the lower bases (102) of the dot pins (96). Film (112) also acts has a physical barrier by preventing contaminants from accessing the actuator assembly (76). Furthermore, film (112) forms a plenum (114) adjacent the lower surface (88) of the deck (84). As best illustrated in
With reference to the cross sectional view of
In order to ensure proper air flow and that none of the dot pins (96) get pneumatically stuck in a raised position, various vents can be incorporated into the display (72). For example,
Although this disclosure has been described in terms of certain embodiments and generally associated methods, alterations and permutations of these embodiments and methods will be apparent to those skilled in the art. Accordingly, the above description of exemplary embodiments does not define or constrain this disclosure. Other changes, substitutions, and alterations are also possible without departing from the spirit and scope of this disclosure.
