EP3769061A1 - Ortsauflösender taktiler sensor und herstellungsverfahren für einen ortsauflösenden taktilen sensor - Google Patents
Ortsauflösender taktiler sensor und herstellungsverfahren für einen ortsauflösenden taktilen sensorInfo
- Publication number
- EP3769061A1 EP3769061A1 EP19748732.5A EP19748732A EP3769061A1 EP 3769061 A1 EP3769061 A1 EP 3769061A1 EP 19748732 A EP19748732 A EP 19748732A EP 3769061 A1 EP3769061 A1 EP 3769061A1
- Authority
- EP
- European Patent Office
- Prior art keywords
- layer
- sensor
- conductor layer
- conductor
- cover
- Prior art date
- Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
- Withdrawn
Links
Classifications
-
- G—PHYSICS
- G01—MEASURING; TESTING
- G01L—MEASURING FORCE, STRESS, TORQUE, WORK, MECHANICAL POWER, MECHANICAL EFFICIENCY, OR FLUID PRESSURE
- G01L5/00—Apparatus for, or methods of, measuring force, work, mechanical power, or torque, specially adapted for specific purposes
- G01L5/22—Apparatus for, or methods of, measuring force, work, mechanical power, or torque, specially adapted for specific purposes for measuring the force applied to control members, e.g. control members of vehicles, triggers
- G01L5/226—Apparatus for, or methods of, measuring force, work, mechanical power, or torque, specially adapted for specific purposes for measuring the force applied to control members, e.g. control members of vehicles, triggers to manipulators, e.g. the force due to gripping
- G01L5/228—Apparatus for, or methods of, measuring force, work, mechanical power, or torque, specially adapted for specific purposes for measuring the force applied to control members, e.g. control members of vehicles, triggers to manipulators, e.g. the force due to gripping using tactile array force sensors
-
- G—PHYSICS
- G01—MEASURING; TESTING
- G01L—MEASURING FORCE, STRESS, TORQUE, WORK, MECHANICAL POWER, MECHANICAL EFFICIENCY, OR FLUID PRESSURE
- G01L1/00—Measuring force or stress, in general
- G01L1/20—Measuring force or stress, in general by measuring variations in ohmic resistance of solid materials or of electrically-conductive fluids; by making use of electrokinetic cells, i.e. liquid-containing cells wherein an electrical potential is produced or varied upon the application of stress
- G01L1/205—Measuring force or stress, in general by measuring variations in ohmic resistance of solid materials or of electrically-conductive fluids; by making use of electrokinetic cells, i.e. liquid-containing cells wherein an electrical potential is produced or varied upon the application of stress using distributed sensing elements
Definitions
- the invention is in the field of mechanical engineering and manufacturing technology and measurement technology and deals specifically with the design and manufacture of sensors.
- pressure-sensitive sensors with a high spatial resolution are considered.
- Tactile sensors are generally known in various types. For example, strain gauges or piezoceramic or piezoresistive sensor materials as well as capacitive or inductive sensors are often used and contacted by means of suitable leads.
- the sensors often have a matrix-like structure with sensor elements distributed over a large area.
- structures with feed lines printed on the cover layer are known. However, due to their liability, these can only be applied to cover materials to a limited extent. That is why thermal sealing is often not possible.
- supply lines can be very strong bends, especially under dynamic stress, break and thus destroy the sensor.
- the present invention has for its object to provide a spatially resolving tactile sensor against the background of the prior art, which is mechanically flexible, easy to manufacture, not specified in terms of design and is provided with a potentially high spatial resolution.
- the invention further relates to a manufacturing method that enables simple and inexpensive manufacture of such sensors with high quality and service life.
- the object is achieved according to the invention with a spatially resolving tactile sensor with the features of claim 1.
- the claims dependent on this claim show possible implementations and extensions of such a sensor.
- the object is further achieved by a method for producing a sensor according to claim 9.
- the dependent claims dependent on this claim show possible implementations of such a method.
- the invention thus relates specifically to a spatially resolving tactile sensor with a first thermoplastic cover layer and with a second thermoplastic cover layer, which is arranged at least in sections parallel to the first thermoplastic cover layer, a sensor arrangement being arranged between the two cover layers, the sensor arrangement being at least a first has a structured conductor layer which is integrally connected to the first cover layer, and wherein the sensor arrangement has a sensor material, in particular structured sensor layer, which is electrically contacting the first conductor layer and has a structured sensor layer, the electrical properties of which depend on a compressive force exerted locally on the sensor material, and wherein the second cover layer, like the first cover layer, is integrally connected to the sensor arrangement.
- the cover layer is advantageously made entirely of a thermoplastic material that can also be welded.
- the sensor layer can be like mentioned structured, but also not structured / unstructured and carried out homogeneously.
- both the cover layers and the first conductor layer and the sensor layer are made as thin as possible.
- the execution of the cover layers as thermoplastic layers enables a thermoplastic welding or gluing of the cover layers to the sensor arrangement, while at the same time the two cover layers can be welded to one another in the area around the sensor arrangement, the contour of the sensor advantageously being retained in order to achieve an overall hermetic closed arrangement to form.
- the thermoplastic material of the cover layers can also penetrate into free areas between individual conductor tracks of a conductor layer during the thermoplastic deformation, so that the conductor tracks are fixed to one another very well and reliably and with reliable electrical insulation. This enables a very fine distribution of the conductor tracks and thus a high spatial resolution with undiminished reliability.
- the fixed conductor layer serves to tap electrical signals or parameters or parameters which are generated or modified by the sensor layer or which characterize a local area of the sensor layer and to be sent to an electronic evaluation system.
- the pressure-sensitive sensor layer is usually designed to be electrically conductive, the resistance of the sensor layer to the conductor layer, which is usually embodied in a plurality of conductor tracks that are separated from one another, usually being significantly greater.
- the different conductor tracks of the first conductor layer come into contact with the sensor layer at different points, so that electrical signals can be picked up and differentiated from different points of the sensor layer.
- An embodiment of the invention can provide that the sensor arrangement has a second structured conductor layer, which is arranged at least in sections parallel to the first structured conductor layer, such that the sensor layer is between the first and the second structured conductor layer is arranged parallel to this and is electrically contacted with the two conductor layers.
- the sensor layer is arranged between a first and a second conductor layer
- electrical voltages or currents or currents between conductor tracks or connections of the first and the second conductor layer can be measured, for example, at different points in the sensor layer.
- the distribution of the conductor tracks of the first and second conductor layers can be different, so that signals can be picked up at the points of intersection of conductor tracks of the different conductor layers at different points of the sensor layer and can be assigned to the measuring point. It can be provided that the conductor tracks or groups of conductor tracks of the first conductor layer intersect with conductor tracks of the second conductor layer, in particular orthogonally.
- a further advantageous embodiment of the invention can provide that the integral connection of the cover layers with the sensor arrangement is produced by the action of heat and / or pressure on at least one cover layer.
- cover layers consist of a thermoplastic material
- this can usually be permanently deformed by heat input / heating via a pour point and / or by the action of pressure. This allows the cover layers to be welded to one another and to the conductor layers which are arranged between them, or to the sensor arrangement. The sensor thus still maintains its functionality even in the case of very strong deformations, such as multiple bending and twisting.
- the invention can also be designed in that the material connection of at least one of the cover layers to the sensor arrangement is provided by an adhesive layer on at least one cover layer.
- an adhesive layer can be realized, for example, by a double-sided adhesive tape or by an adhesive applied to a cover layer or a conductor layer in liquid or pasty form.
- a conductor layer can be placed on such an adhesive layer are applied, and then the unit thus created can be joined together with the remaining parts of the sensor, that is to say with the sensor layer, optionally a second conductor layer and a second cover layer. Further details of the method of producing a sensor are explained below.
- a further advantageous embodiment can provide that the first and / or the second conductor layer is at least partially designed as a textile conductor layer.
- the formation of a conductor layer as a textile conductor layer enables a very high mobility of the conductor layer without the risk of material fatigue.
- the formation of a conductor layer as a thin, printed, solid conductor layer is also conceivable, but with a textile conductor layer a higher mechanical flexibility and bendability of the sensor is achieved with the same service life.
- a textile conductor layer can consist, for example, of a mesh of conductive fibers or a mesh of conductive and non-electrically conductive fibers.
- a further embodiment of the invention can provide that the first and the second cover layer are directly bonded to one another in one or more sealing sections, in particular welded or glued. It is a great advantage of the choice of materials for the cover layers that they can be connected both to the sensor arrangement, for example directly to the electrical conductor layers, and also directly to one another. This ensures good mechanical cohesion of the sensor, and the cover layers can also be connected to one another in such a way that they seal the sensor all around in a fluid-tight manner, for example also in an air-tight manner. This also protects the sensor from external signs of aging due to corrosion and thus a loss of sensitivity.
- the sensor material is a piezoresistive material. This allows the conductor tracks of the two conductor layers, each with sections of the Sensor layer are connected, based on the change in electrical resistance, the pressure on the corresponding area of the sensor layer be measured.
- a piezoceramic material can also be used which generates a piezo voltage when exposed to pressure, so that a voltage signal can be tapped depending on the location by means of the conductor tracks when subjected to pressure.
- a capacitive sensor can also be constructed with a dielectric material.
- the invention also relates to a method for producing a spatially resolving tactile sensor with a first thermoplastic cover layer and with a second thermoplastic cover layer and with a sensor arrangement arranged and sealed between the two cover layers, which has at least a first Structured conductor layer and a sensor layer having a sensor material that is in electrical contact with the first conductor layer, characterized in that a full-surface textile conductor layer is cohesively bonded to a self-supporting base that there is a pattern of for producing the structured first conductor layer from the full-surface conductor layer Cut out conductor tracks and remove the rest of the conductor layer and that the structured first conductor layer is joined to the base on the one hand and the sensor layer on the other hand and both are sealed together between the first and the second cover layer by the action of heat and / or by the action of pressure.
- the first conductor layer In the production method described, there is the advantage in particular in the design of the first conductor layer that it can be fixed on a self-supporting base (e.g. double-sided adhesive tape) before cutting out conductor tracks and can also remain on this base during the further joining of the sensor , If thin conductor layers are used for the production of the sensor, then the corresponding conductor tracks have only a very low rigidity compared to the self-supporting base. By fixing on a self-supporting base, the conductor tracks are reliably arranged and fixed at a distance from one another, so that their electrical insulation from one another can be ensured. In order to can be used for a sensor of the type described in the manufacturing method according to the invention very thin conductor layers.
- a self-supporting base e.g. double-sided adhesive tape
- All bodies can be used as a self-supporting base, which can be handled independently of other bodies and without further support, such as. B. textiles, flat objects, plates, sheets and the like.
- an advantageous embodiment of the method can provide that the self-supporting underlay is formed by the first cover layer or by the first cover layer coated with an adhesive layer or by a double-sided adhesive layer (double-sided adhesive tape).
- the first conductor layer can therefore not only be fixed directly on the first cover layer, but can also be fastened thereon by means of an adhesive layer, which can either be designed as a double-sided adhesive tape or as an applied liquid or pasty adhesive. If the first conductor layer is attached directly to the first cover layer, this can be done by thermoplastic fusion, as a result of which the first conductor layer is connected directly to the first cover layer, in particular with a positive fit.
- a further embodiment of the method according to the invention can provide that either the self-supporting base is cut together with the first conductor layer and is removed except for the conductor tracks that remain, or that the first conductor layer on the self-supporting base is cut separately and that cut-out partial areas of the first conductor layer are separated from the Underlay are removed, while the underlay and other sub-areas of the conductor layer remain as a structured conductor layer.
- the result is a sandwich-like structure with two layers, namely the first conductor layer and the base supporting it, the base being designed as a pure adhesive layer or as a cover layer.
- an embodiment of the method according to the invention can provide that the textile conductor layer is cut by laser cutting or by means of a cutting plotter. Processes such as stamping, water jet cutting, etching or other ablative processes are also conceivable.
- a further advantageous embodiment of the invention can provide that the structured first conductor layer is joined to the base and the sensor layer is joined to a second conductor layer, and these layers are sealed together between the first and the second cover layer by the action of heat and / or by the action of pressure. Sealing the sensor between the cover layers represents a particularly simple method of assembly, which at the same time creates the seal against fluids, in particular moisture, but also gases. Since the thermoplastic cover layers adhere to each other as well as to the sensor arrangement, overall good cohesion is ensured.
- the second conductor layer is structured in the same way as the first conductor layer before being joined together with the first conductor layer and the sensor layer.
- This can also be used to implement complicated sensor arrangements which, via matrix-like intersections of the conductor tracks of two conductor layers, allow the assignment of surface areas of the sensor layer distributed in a matrix-like manner to the individual conductor tracks.
- the conductor tracks of the different conductor layers can run orthogonally or at an angle other than 90 ° to one another. However, the conductor tracks can also be curved in whole or in sections.
- the method according to the invention can also provide that the thermoplastic deformation of the cover layers is carried out to such an extent that thermoplastic material from at least one cover layer or even an adhesive reaches the areas of the sensor arrangement which lie between the conductor tracks of the first and / or second conductor layer , This ensures not only a mechanical fixation of the sensor, but also a reliable definition of individual conductor tracks and their electrical isolation from each other. In addition, the likelihood of air and moisture inclusions between the cover layers is minimized.
- the first and the second cover layer are thermoplastic welded or glued together in an edge area region surrounding the sensor arrangement. In this way, a fluid-tight closure of the sensor can be achieved in its outer edge area.
- first and the second cover layer are thermoplastic welded or glued to one another in one or more intermediate areas, in which the sensor arrangement has through openings, in addition to the edge surface area. This results in a further filling of cavities within the sensor arrangement by the thermoplastic or an adhesive, and thus a stronger cohesion of the sensor and the reliable filling of cavities.
- Fig. 7 is a view of a sensor arrangement with a first conductor layer, a second conductor layer and a sensor layer and 8 is a view of a sensor arrangement in which the conductor tracks of the different conductor layers cross one another orthogonally.
- 1 shows in cross section a layer sequence of a spatially resolving tactile sensor, the following layers following one another from top to bottom: 1 denotes the first thermoplastic cover layer; 6 denotes an adhesive layer which is structured together with the first conductor layer 3.
- the sensor layer 4 is arranged as the middle layer in the sensor. Below the middle, the structure is repeated in the reverse order, 5 denotes the structured conductor layer, 7 the likewise structured adhesive layer and 2 the second thermoplastic cover layer.
- the cross-sectional view in FIG. 1 and the following figures show the individual elements of the sensor in an exploded view, not to scale, and before the two cover layers 1, 2 are connected.
- FIG. 2 shows a variant of the sensor in which a continuous adhesive layer 6 is arranged on the first cover layer 1, on which the structured first conductor layer 3 is attached.
- a sensor layer 4 In the middle of the sensor there is again a sensor layer 4, followed by a second structured conductor layer 5, a continuous adhesive layer 7 and the second thermoplastic cover layer 2.
- the illustrated conductor path of the second conductor layer 5 runs parallel to the plane of the drawing, while the conductor paths of the first conductor layer cross the plane of the drawing in Figure 2.
- FIG. 3 shows a structure similar to that of FIG. 2, the sensor layer 4 also being structured such that it is divided into individual sections.
- the individual sections can be shaped as strips or square or round fields.
- FIG. 4 shows a simple design of a sensor with a first and a second cover layer 1, 2, an adhesive layer 6 being arranged on the first cover layer 1 and a structured first conductor layer 3 arranged thereon.
- One is adjacent to the structured first conductor layer 3 Arranged sensor layer 4, which is immediately followed by a second thermoplastic cover layer 2.
- the adhesive layers 6, 7 between the thermoplastic cover layers 1, 2 and the conductor layers 3, 5 can also be omitted if the conductor layers 3, 5 are directly on the thermoplastic cover layers 1 , 2 stick. This can be achieved, for example, by initially pressing or partially melting the thermoplastic cover layers in contact with the conductor layers 3, 5.
- FIG. 5 shows a top view of the structured first conductor layer 3. This is divided into feed lines 3a and a round, divided into sectors field of sensor electrodes 3b.
- FIG. 6 shows a top view of the second structured conductor layer 5, which is divided into supply lines 5a and an array of concentric rings 5b, which in turn form sensor electrodes.
- FIG. 7 shows a top view of the sensor arrangement, the conductor layers 3, 5 lying one above the other being recognizable.
- a sensor layer 4 is arranged between these, and the conductor layers are enclosed on the outside between two optically transparent thermoplastic cover layers and pressed and / or welded and sealed in an edge region along the dashed line 10.
- FIG. 8 shows a top view of a sensor arrangement in which the conductor tracks of different conductor layers cross one another orthogonally.
- the tactile sensor according to the invention is thus easy to manufacture, hermetically sealed and, inter alia, very stable through the use of thermoplastic cover layers, so that mutual contacting of leads 3a, 5a and contact electrodes 3b, 5b of the conductor layers can be ruled out despite the fine structuring. This makes the sensor very reliable despite its high flexibility.
Landscapes
- Physics & Mathematics (AREA)
- General Physics & Mathematics (AREA)
- Chemical & Material Sciences (AREA)
- Analytical Chemistry (AREA)
- Force Measurement Appropriate To Specific Purposes (AREA)
Abstract
Description
Claims
Applications Claiming Priority (2)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| DE102018211680.6A DE102018211680A1 (de) | 2018-07-12 | 2018-07-12 | Ortsauflösender taktiler Sensor und Herstellungsverfahren für einen ortsauflösenden taktilen Sensor |
| PCT/EP2019/068765 WO2020011956A1 (de) | 2018-07-12 | 2019-07-11 | Ortsauflösender taktiler sensor und herstellungsverfahren für einen ortsauflösenden taktilen sensor |
Publications (1)
| Publication Number | Publication Date |
|---|---|
| EP3769061A1 true EP3769061A1 (de) | 2021-01-27 |
Family
ID=67514584
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| EP19748732.5A Withdrawn EP3769061A1 (de) | 2018-07-12 | 2019-07-11 | Ortsauflösender taktiler sensor und herstellungsverfahren für einen ortsauflösenden taktilen sensor |
Country Status (3)
| Country | Link |
|---|---|
| EP (1) | EP3769061A1 (de) |
| DE (1) | DE102018211680A1 (de) |
| WO (1) | WO2020011956A1 (de) |
Families Citing this family (3)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| KR102682582B1 (ko) | 2019-06-24 | 2024-07-05 | 알베르트-루드비히스-우니베르시테트 프라이부르크 | 촉각 센서 및 촉각 센서를 작동하는 방법 |
| CN111947814B (zh) * | 2020-08-11 | 2021-12-17 | 上海海事大学 | 一种柔性三维触觉传感器及其制作、检测方法 |
| CN119124415B (zh) * | 2024-05-27 | 2025-11-28 | 浙江大学 | 一种高灵敏水下柔性触觉传感器及压力检测方法 |
Citations (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| DE69011672T2 (de) * | 1989-12-11 | 1995-02-02 | Tekscan, Inc., Boston, Mass. | Flexibler taktischer sensor zum messen der druckverteilungen vom fuss und von dichtungen. |
Family Cites Families (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| DE102007022871A1 (de) * | 2007-05-14 | 2008-11-20 | Fraunhofer-Gesellschaft zur Förderung der angewandten Forschung e.V. | Taktilsensor mit entkoppelten Sensorzellen |
-
2018
- 2018-07-12 DE DE102018211680.6A patent/DE102018211680A1/de not_active Withdrawn
-
2019
- 2019-07-11 WO PCT/EP2019/068765 patent/WO2020011956A1/de not_active Ceased
- 2019-07-11 EP EP19748732.5A patent/EP3769061A1/de not_active Withdrawn
Patent Citations (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| DE69011672T2 (de) * | 1989-12-11 | 1995-02-02 | Tekscan, Inc., Boston, Mass. | Flexibler taktischer sensor zum messen der druckverteilungen vom fuss und von dichtungen. |
Also Published As
| Publication number | Publication date |
|---|---|
| DE102018211680A1 (de) | 2020-01-16 |
| WO2020011956A1 (de) | 2020-01-16 |
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