Roller

Abstract

A roller including a roller body in a cylindrical form. The roller body comprises at least partially of a borosilicate glass material.

Claims

1. A roller for roller conveyers comprising: a roller body in a cylindrical form, the roller body comprising at least partially of a borosilicate glass material, and the roller body is a glass tube, wherein the glass tube has a first open end and a second open end and at least one of the first and second open end comprises at least one of a bearing and a bushing, wherein the material of at least one of the bearing and bushing and of the glass tube has essentially the same coefficient of expansion .sub.20-300 C. in the region 3.sub.+10.sup.6 1/K to 10.sub.+10.sup.6 1/K.

2. The roller according to claim 1, wherein the roller comprises an axle fed through at least one of the bearing and the bushing into the glass tube.

3. The roller according to claim 1, wherein the glass tube has an outer surface and an inner surface, wherein the inner surface of the glass tube comprises a protective coating.

4. The roller according to claim 1, wherein the glass tube has an outer surface and an inner surface, wherein the outer surface is a shaped surface.

5. The roller according to claim 4, wherein the shaped surface has grooves.

6. The roller according to claim 1, wherein the roller comprises one or more sensor elements.

7. The roller according to claim 6, wherein the sensor elements are mounted within the glass tube along at least one of the interior surface and the axle fed through the glass tube.

8. The roller according to claim 1, wherein the roller comprises a drive element.

9. The roller according to claim 8, wherein the drive element is an electric motor situated within the glass tube.

10. The roller according to claim 1, wherein the glass tube has an outer surface and an inner surface, and the glass tube comprises a coating on the outer surface.

11. The roller according to claim 1, wherein the glass tube has a wall-thickness in the range of 1.5 mm to 20 mm.

12. A roller conveyor for the transportation of goods, comprising at least one or more of a passive and a driven roller, wherein each roller comprises: a roller body in a cylindrical form, the roller body comprising at least partially of a borosilicate glass material, and the roller body is a glass tube, wherein the glass tube has a first open end and a second open end and at least one of the first and second open end comprises at least one of a bearing and a bushing, wherein the material of at least one of the bearing and bushing and of the glass tube has essentially the same coefficient of expansion .sub.20-300 C. in the region 3.sub.+10.sup.6 1/K to 10.sub.+10.sup.6 1/K.

Description

BRIEF DESCRIPTION OF THE DRAWINGS

(1) The above-mentioned and other features and advantages of this invention, and the manner of attaining them, will become more apparent and the invention will be better understood by reference to the following description of (an) embodiment(s) of the invention taken in conjunction with the accompanying drawing(s), wherein:

(2) FIG. 1 illustrates a schematic view of a roller made from a borosilicate glass tube with integrated bearings or bushings to enable free movement of the roller and the possibility of an integrated sensor element, according to an embodiment of the invention;

(3) FIG. 2 illustrates a cross sectional end view of the borosilicate glass tube around a central axle with integrated sensors, according to an embodiment of the invention; and

(4) FIG. 3 illustrates an isometric layout of the borosilicate glass tube with the sensor position along the central axle, according to an embodiment of the invention.

(5) Corresponding reference characters indicate corresponding parts throughout the several views. The exemplification(s) set out herein illustrate(s) (one) embodiment(s) of the invention (, in one form,) and such exemplification(s) (is)(are) not to be construed as limiting the scope of the invention in any manner.

DETAILED DESCRIPTION OF THE INVENTION

(6) FIG. 1 depicts a cross sectional view of a roller according to an embodiment of the invention. The roller according to the invention is denoted with reference number 4. The roller according to the invention comprises a glass body of a glass material, especially a borosilicate glass material. The glass body in the depicted embodiment is a glass tube 8 of cylindrical shape. The glass tube 8 has two free ends, a first end, a second end, onto which a bearing and/or bushing could be mounted. The bearing and/or bushing closes the open ends of the glass tube 8. Through the bearings and/or bushings 7 an axle 2 is guided into the center of the glass tube 8. Such an arrangement provides for a free movement at both ends of the glass tube of the axle 2 through the center of the glass tube 8. The glass tube 8 has a inner surface 5 as well as an outer surface. In order to adapt the failure mode of the borosilicate glass tube 8 under excessive load or impact forces the inner surface 5 of the glass tube can be coated with a UV-protective coating.

(7) For drive purposes using polymer drive belts such as cyclothan belts 6 the glass tube can be shaped on the outer surface. In the embodiment shown grooves 9 are formed in the outer surface. By the polymer drive belts of non-driven or driven rollers could be linked together. The glass tube allows for the integration of sensors within the tube. The sensors can be for example optical sensors. Such optical sensors 3A, 3B can be mounted internally of the glass tube along the interior surface, such as sensor 3B or on the axle itself, such as sensor 3A. Sensor 3A mounted on to the axle can be provided with data or energy via a data energy line 1 passing into the roller through the axle 2. As an alternative to the sensors or in addition thereto an internally driven motor in place of sensors 3A, 3B allow for a visual inspection of the motor and the bearings through the borosilicate glass tube 8. In order to prevent water or dust to ingress from industrial cleaning processes the bearing and/or bushing 7 can be made from materials having essential the same thermal expansion coefficient as the glass tube. In case the bearing and/or bushing 7 has essential the same thermal expansion coefficient as the glass tube the glass tube is sealed against damages. The sealing can be accomplished by using silicons, two component adhesives or UV glueing.

(8) In order to give the roller an improved performance with respect to lifetime, cleaning, aesthetics or to match the sensor optics 3A, 3B the borosilicate glass tube 8 can have an external surface coating 4 on the outer surface of the glass tube 8. The external surface coating 4 could be anti-scratch and/or anti reflective coatings. The application of coatings will lead to improvements towards visibility in combination with the use of sensors. The borosilicate glass tube comprises a borosilicate glass as described for example in the publication SCHOTT, Guide to glass, second edition page 25. Such a borosilicate glass comprise a high percentage of SiO.sub.2 (70-80 weight-%) and furthermore 7-13 weight-% boric oxide (B.sub.2O.sub.3), 4-8 weight-% Na.sub.2O and K.sub.2O and 2-7 weight-% aluminum oxide (Al.sub.2O.sub.3). Glasses with such a composition show a high resistance to corrosion and temperature change. For this reason they are used in process plants for example in chemical industries. In particular in dangerous environments such as in case of exposition to chemicals, heat, etc. the use of borosilicate glass 3.3, which is also known as DURAN-glass of DURAN group GmbH is advantageous. According to the data sheet of DURAN group GmbH, Hattenbergstrae 10, 55120 Mainz, brosilicate glass 3.3 has the following composition: 81 weight-% SiO.sub.2, 13 weight-% B.sub.2O.sub.3, 4 weight-% Na.sub.2O and K.sub.2O, 2 weight-% Al.sub.2O.sub.3. All physical data of DURAN-glass are published on http://www.duran-group.com/de/ueber-duran/duran-eigenschaften.html.

(9) An alternative borosilicate glasses is a borosilicate glasses of the FIOLAX-type. FIOLAX is a brand of Schott AG, Hattenbergstrae 10, 55120 Mainz. The composition of FIOLAX clear according to the data sheet FIOLAX of Schott AG, published on http://www.schott.com/d/tubing, is 75 weight-% SiO.sub.2, 10.5 weight-% B.sub.2O.sub.3, 5 weight-% Al.sub.2O.sub.3. 7 weight-% Na.sub.2O, 1.5 weight-% CaO. A different type of a FIOLAX is FIOLAX amber. The content of all the aforementioned publications are hereby incorporated by reference in their entirety into the present application.

(10) FIG. 2 shows a cross sectional view of one end of a roller comprising a borosilicate glass tube 8, according to an embodiment of the invention. The borosilicate glass tube 8 is arranged around a central axle 2. Sensors can be arranged around the central axle 2. The axle 2 has a shaped end 10, which can be mounted into a conveyor system for easy fitting and removal. The borosilicate glass tube 8 has preferably a wall thickness of 1.8 to 10 mm.

(11) Reference number 3A in FIG. 2 describes a sensor arranged around the axle of the glass tube.

(12) FIG. 3 shows a three-dimensional view of a glass tube 8 with a central axle 2, according to an embodiment of the invention. The glass tube 8 is shown with open ends and has the form of a cylinder. The wall thickness of the glass tube is between 1.8 mm to 10 mm. Along the length of the axis of the roller sensors are arranged. The arrangement of sensors along the complete axle 2 of the roller allows that conveyed items across the internal length of the roller could be detected.

(13) The inventive rollers manufactured from a glass tube have unique improvements over rollers shown in the state of the art being from a metal material or a polymer tube. The using of a glass tube instead of a metal or polymer tube allows for internally mounted sensors. The glass tube furthermore gives the possibility of visual inspection of an internal area such as bearings or motors for maintenance.

(14) Furthermore the borosilicate glass tube has advantages such as low corrosion and a improved resistance. Furthermore due to a high surface smoothness by borosilicate glass tubes as rollers conveying of certain items and cleaning of the surface is improved. Using glass tubes has a lot of further advantages over rollers according to the state of the art. The hardness of the glass material provides for a longer lifetime in case abrasive or hard products are conveyed. Furthermore the cleaning is improved since glass materials have a high chemical resistance and an impermeability to liquids and gases. Glass tubes are antibacterial and therefore safe for food. The glass tubes can be provided with self-cleaning coatings in order to provide for easy cleaning. The coatings of the glass tube can be applied onto the outer surface as well as onto the inner surface. By the coatings surface characteristics for different applications can be applied. It is possible to coat the glass tubes with conductive coatings and/or protective coatings in order to improve strengths and avoid scratches. Also functional coatings are possible. The transparence of the glass tubes allow for an internal inspection of sensors and driving systems. The sensors are protected due to the fact that glass tubes are impermeable to liquids and gases. The transmission of the glass tube is adjustable. Furthermore the glass tube can be sealed to metals, such as bushings and/or bearings. The glass tubes have a very low thermal conductivity and a high thermal shock resistance as well as a low thermal expansion coefficient. Furthermore borosilicate glass tubes are corrosion resistant even in a cold water environment. By using glass tubes the lifetime of the roller can be significantly increased. Under the environmental aspect a further advantage of the glass tube is that they are recyclable and resistant to radioactive radiation.

(15) The glass tubes can be providing in width up to 1500 mm with an outside diameter>50 mm and a wall thickness from 1.8 mm to 9 mm. Due to the integrated grooves in the external surface the glass tube can be driven by cyclothan-polymer drive belts. Possible thermoplastic coatings prevent accumulated defects causing a reduced lifecycle during use.

(16) While this invention has been described with respect to at least one embodiment, the present invention can be further modified within the spirit and scope of this disclosure. This application is therefore intended to cover any variations, uses, or adaptations of the invention using its general principles. Further, this application is intended to cover such departures from the present disclosure as come within known or customary practice in the art to which this invention pertains and which fall within the limits of the appended claims.