Patent ID: 12212702

DETAILED DESCRIPTION OF ILLUSTRATIVE EMBODIMENTS

The present invention, in some embodiments thereof, relates to a mechanism for retracting and extending a retractable portion of a display screen and, more specifically, but not exclusively, to a retractable electronic display screen that is extended and retracted by a rack-and-pinion system acting in concert with a torsion spring.

Before explaining at least one embodiment of the invention in detail, it is to be understood that the invention is not necessarily limited in its application to the details of construction and the arrangement of the components and/or methods set forth in the following description and/or illustrated in the drawings and/or the Examples. The invention is capable of other embodiments or of being practiced or carried out in various ways.

Reference is now made toFIGS.1A-2B. Device10includes a retractable display screen12. Device10may be any device that has a display screen, such as a smart phone, tablet, or smart television device.

Display screen12is supported on a frame14. Frame14includes two parallel supports22. One support22is configured along an upper edge21of the frame14, and a second support22is configured along a lower edge23of the frame14. The terms upper edge21and lower edge23are used to describe opposing edges. Since the device10may be held in any direction, either of supports22may be an upper edge21, or a lower edge23. For purposes of illustration, upper edge21is depicted adjacent to cameras20, which would usually be upright when the device is held by a user, and lower edge23is depicted on the opposing edge. Helical torsion spring24, roller26, and stopper15are not visible inFIGS.1A-2B, but their locations are indicated. The supports22, torsion spring24, roller26, and stopper15are part of a mechanism for retracting and extending the retractable portion16, in a manner that will be described further herein.

InFIGS.1A and1B, the retractable display screen12is in an extended position. In the extended position, the entire screen12is visible from one side of the device10, referred to herein as the front of the device10. InFIGS.2A and2B, the retractable display screen12is in a retracted position. In the retracted position, only portion18of the display screen is visible from the front of the device10, and portion16of the display screen is visible from the rear of the device10. Axis A depicts the dividing point between portion18and portion16of the display screen12. The term “retractable portion” refers to portion18, which is retracted or extended using the system described herein. Portion16is referred to herein as the non-retractable portion, because portion16moves only ancillary to movement of the retractable portion18. The direction of retraction is indicated by arrow B inFIG.1A.

As seen inFIG.2A, frame14also includes user interfaces11,13, for controlling features of device10. User interfaces11,13may be depressible buttons. User interface11may control a release of stopper15for extending the display screen12, as will be explained further herein. User interface13may be an on/off switch for the device10. The frame14may also include other components typically included in the electronic device10, such as one or more cameras20.

As seen best inFIGS.1A and1B, racks28are mechanically connected to the retractable portion18of the screen. When the screen12is supported within the frame14, racks28are configured along the upper edge and lower edge of the frame14, respectively.

Referring now toFIGS.3and4, the mechanism for retracting and extending retractable portion16is shown in detail. As seen inFIG.3, helical torsion spring24extends between the upper and lower edges of the frame14. The length of the torsion spring24is selected so that each end of the torsion spring24attaches to an upper or lower edge, respectively, of the frame14. Pinions30are mechanically connected to the torsion spring24and are configured to rotate along the racks28. The pinions30have gear teeth that cooperate with the racks28in a rack-and-pinion system, in a manner known to those of skill in the art. Rotation of the pinions30is thus transferred to in-plane movement of the retractable portion18.

To retract the screen12, a user pushes the retractable portion18in the direction of arrow B inFIG.1A, for example, with a finger. The non-retractable portion16(not shown inFIG.3) curls in the direction of arrow R around roller26until it assumes the position ofFIGS.2A and2B. Simultaneously, the movement of rack28causes pinions30to rotate. This rotation of the pinions30causes an increase in potential energy of the torsion spring24.

The user continues to push the retractable portion18until the retractable portion18is completely retracted. At this point, stopper15(not shown inFIG.3) engages one or both pinions30, and/or the retractable screen12, to prevent further rotation of the pinions30and fix the screen12in the retracted position. Stopper15may take any form suitable for fixing the screen12. For example, stopper15may be a rod that is removably inserted between the teeth of pinions30when the screen12is completely retracted. Optionally, the stopper15may include a mechanical actuator which is automatically engaged by the screen12itself, when the screen12is fully retracted. Stopper15may also be manually actuated, such as with push button11. The location of the stopper15is highly dependent on the detailed architecture design of the device10, and can vary according to design needs for other architectural elements.

To extend the retractable portion, the user releases the stopper15, for example, by pushing push button11. The release of the stopper15allows the potential energy stored in the torsion spring24to be discharged through rotation of the torsion spring24. The rotation of torsion spring24, in turn, causes the pinions30to rotate. The rotation of the pinions30is translated to in-plane movement of the rack28, which causes retractable portion18to extend outward, until the position ofFIGS.1A and1Bis attained again.

Advantageously, the mechanism for expanding and retracting the screen12disclosed herein utilizes a small number of moving parts. This allows the device10to be constructed in a compact and simple fashion. In addition, the use of the torsion spring24makes the mechanism entirely reliant on mechanical forces, without requiring use of motors. In addition, the rack-and-pinion system and the torsion spring are integrated, so that retraction of the display screen automatically supplies the energy for subsequent extension of the display screen, without requiring supply of any additional energy.

Referring now toFIG.5, helical torsion spring24may include two torsion springs24a,24b, joined by grounding section36. Each of the torsion springs24a,24bhas, respectively, a first end32a,32battached to a pinion, and a second end34a,34b, attached to the grounding section. The two helical torsion springs24a,24bmay, in combination, function mechanically similarly to a single torsion spring24. An advantage of using two helical torsion springs24a,24b, is that the grounding36takes up less space than torsion spring24, and thus frees up space for inclusion of other components of device10. The number of torsion springs used in the device10may be determined by detailed antenna design and the clearance needed by other components of the device. Thus, more than two torsion springs24may also be used in device10.

The physical parameters of spring24, such as material, diameter, number of coils, and the like, may be engineered to meet requirements of roll and unroll speed and feeling. In one exemplary embodiment, the spring is made of music wire. Preferably, the music wire complies with the parameters of ASTM standard A228/A228M, for Steel Wire and Music Spring Quality. In one exemplary embodiment, the minimum tensile strength of the music wire spring material is around 318×103psi, which corresponds to 2192 MPa. The Design Stress may be less than 45% of Minimum Tensile, which is 986 MPa.

Similarly, the physical parameters of the pinions30and forces exerted thereby may be engineered according to desired size and feeling requirements. In one exemplary embodiment, the pinions rotate three times during a rolling or unrolling process. The length of each round is 16.5 mm. The gear pitch radius may be 2.5 mm. The intermittent torque may be 35 mNm (milli-Newton meters), and the intermittent force, calculated as intermittent torque divided by gear pitch radius, may be 14 N. The continuous torque may be 25 mNm, so that the continuous force, calculated as continuous torque divided by gear pitch radius, is 10 N.

FIG.6illustrates certain physical parameters of torsion spring24, as the spring24is subjected to increased bending stress when the screen12is moved from the extended position to the retracted position. Arrow F inFIG.6represents an increase in force as the spring is moved along deflection angle φ. The change in deflection angle φ is shown as a dot-dash line. The output force F exerted on the spring is calculated based on the following equation:

F=π3⁢2⁢d3r⁢σ
where d is the diameter of the spring (as illustrated inFIG.6), r is the spring length (as illustrated inFIG.6), and σ is the bending stress. The deflection angle φ is determined by the following equation:

φ=2⁢D⁢π⁢nE⁢d⁢σ⁢1⁢8⁢0π
where D is the mean coil diameter (as illustrated inFIG.6), E is the Young's modulus, d is the diameter of the spring wire, and σ is the bending stress.

As can be seen from these equations, for a given spring in which the spring diameter, mean coil diameter, Young's modulus, and spring length r are fixed, the angle φ and the force F are both linearly dependent on the bending stress σ. In one exemplary spring, the diameter d is 0.73×10−3m, the mean coil diameter D is 5.27×10−3m, the spring length r is 2.5×10−3m, and the Young's modulus is 207×109Pa. In addition, in an exemplary embodiment, the number of active coils n may be 100, and the total spring length is 73×10−3m (spring diameter d×number of active coils n). Following the above-referenced formulas, when the preload bending stress σ (also known as preload deflection) is 3.27×106Pa, the output force F is 5 N, and the spring deflection φ is 410.92 degrees. When the bending stress σ is increased to 1178.27×106Pa, the output force is increased to 18 N, and the spring deflection φ is increased to 1479.33 degrees.

The descriptions of the various embodiments of the present invention have been presented for purposes of illustration, but are not intended to be exhaustive or limited to the embodiments disclosed. Many modifications and variations will be apparent to those of ordinary skill in the art without departing from the scope and spirit of the described embodiments. The terminology used herein was chosen to best explain the principles of the embodiments, the practical application or technical improvement over technologies found in the marketplace, or to enable others of ordinary skill in the art to understand the embodiments disclosed herein.

It is expected that during the life of a patent maturing from this application many relevant devices having display screens will be developed and the scope of the terms device and display screen is intended to include all such new technologies a priori.

As used herein the term “about” refers to ±10%.

The terms “comprises”, “comprising”, “includes”, “including”, “having” and their conjugates mean “including but not limited to”. This term encompasses the terms “consisting of” and “consisting essentially of”.

The phrase “consisting essentially of” means that the composition or method may include additional ingredients and/or steps, but only if the additional ingredients and/or steps do not materially alter the basic and novel characteristics of the claimed composition or method.

As used herein, the singular form “a”, “an” and “the” include plural references unless the context clearly dictates otherwise. For example, the term “a compound” or “at least one compound” may include a plurality of compounds, including mixtures thereof.

The word “exemplary” is used herein to mean “serving as an example, instance or illustration”. Any embodiment described as “exemplary” is not necessarily to be construed as preferred or advantageous over other embodiments and/or to exclude the incorporation of features from other embodiments.

The word “optionally” is used herein to mean “is provided in some embodiments and not provided in other embodiments”. Any particular embodiment of the invention may include a plurality of “optional” features unless such features conflict.

Throughout this application, various embodiments of this invention may be presented in a range format. It should be understood that the description in range format is merely for convenience and brevity and should not be construed as an inflexible limitation on the scope of the invention. Accordingly, the description of a range should be considered to have specifically disclosed all the possible subranges as well as individual numerical values within that range. For example, description of a range such as from 1 to 6 should be considered to have specifically disclosed subranges such as from 1 to 3, from 1 to 4, from 1 to 5, from 2 to 4, from 2 to 6, from 3 to 6 etc., as well as individual numbers within that range, for example, 1, 2, 3, 4, 5, and 6. This applies regardless of the breadth of the range.

Whenever a numerical range is indicated herein, it is meant to include any cited numeral (fractional or integral) within the indicated range. The phrases “ranging/ranges between” a first indicate number and a second indicate number and “ranging/ranges from” a first indicate number “to” a second indicate number are used herein interchangeably and are meant to include the first and second indicated numbers and all the fractional and integral numerals therebetween.

It is appreciated that certain features of the invention, which are, for clarity, described in the context of separate embodiments, may also be provided in combination in a single embodiment. Conversely, various features of the invention, which are, for brevity, described in the context of a single embodiment, may also be provided separately or in any suitable subcombination or as suitable in any other described embodiment of the invention. Certain features described in the context of various embodiments are not to be considered essential features of those embodiments, unless the embodiment is inoperative without those elements.

All publications, patents and patent applications mentioned in this specification are herein incorporated in their entirety by reference into the specification, to the same extent as if each individual publication, patent or patent application was specifically and individually indicated to be incorporated herein by reference. In addition, citation or identification of any reference in this application shall not be construed as an admission that such reference is available as prior art to the present invention. To the extent that section headings are used, they should not be construed as necessarily limiting.