METERING DEVICE FOR A FLUID

• US 20150190837A1
• Filed: 09/16/2013
• Published: 07/09/2015
• Est. Priority Date: 09/19/2012
• Status: Active Grant

• Current Assignee: Nordson Corporation
• Original Assignee: Nordson Corporation
• Inventors: Burmester, Thomas, Lippelt, Helge
• Granted Patent: US 10,155,242 B2
• Time in Patent Office: Days
• US Class Current: 1/1
• CPC Class Codes: B05C 11/1002 Means for controlling supply, i.e. flow or pressure, of liquid or other fluent material to the applying apparatus, e.g. valves
• CPC Class Codes: B05C 5/0254 Coating heads with slot-shaped outlet B05C5/0283 takes precedence
• CPC Class Codes: G01F 13/00 Apparatus for measuring by volume and delivering fluids or fluent solid materials, not provided for in the preceding groups
• CPC Class Codes: G01F 15/006 characterised by the use of a particular material, e.g. anti-corrosive material G01F15/14 takes precedence
• CPC Class Codes: G01P 3/36 Devices characterised by the use of optical means, e.g. using infrared, visible, or ultraviolet light G01P3/68 takes precedence; gyrometers using the Sagnac effect, i.e. rotation-induced shifts between counter-rotating electromagnetic beams G01C19/64
• CPC Class Codes: G01P 3/486 delivered by photo-electric detectors

Abstract

The invention relates to a metering device (5) for a fluid, in particular hot melt adhesive, adapted for use with a dispensing apparatus (1) for said fluid or a remote metering apparatus (16) for transporting said fluid, comprising a housing (28), said housing comprising a fluid inlet and one or more fluid outlets, a gear (34) which is rotatably supported in said housing (28) and inserted in a gear chamber (31) in the housing (28) such that a cavity for fluid transport is formed in between two adjacent teeth and said housing (28), one or more chamber inlets in fluid communication with said fluid inlet and said gear chamber (31) such that fluid may flow into said gear chamber (31).

Claims

1. A metering device for a fluid, in particular hot melt adhesive, adapted for use with a dispensing apparatus for said fluid or a remote metering apparatus for transporting said fluid, comprising

a housing, said housing comprising a fluid inlet and one or more fluid outlets,

a gear, said gear being rotatably supported in said housing and inserted in a gear chamber inside the housing such that a cavity for fluid transport is formed in between two adjacent teeth and said housing,

one or more chamber inlets in fluid communication with said fluid inlet and said gear chamber such that fluid may enter the gear chamber, and

one or more chamber outlets in fluid communication with said one or more fluid outlets and said gear chamber such that fluid is transported inside said cavities between said gear and a wall of said gear chamber towards the one or more chamber outlets and may flow towards the one or more fluid outlets,

characterized by a measuring unit for contactless optical detection of the rotational speed of the gear, wherein

the measuring unit comprises one or more probes which are received, preferably light-sealingly and fluid-sealingly, within a correspondingly formed recess formed in said housing and which are adapted to emit light onto a portion of the gear, said recess being spaced apart from the rotating axle of the gear;

the portion of the gear is located in between the tip diameter and the root diameter of said gear; and

the measuring unit comprises a light source for producing light and one or more fiber optics for guiding said light from the light source towards said probe.

2. The metering device according to claim 1, characterized in that the probe is adapted to receive light emitted by the light source.

3. The metering device according to claim 2, characterized in that the probe is adapted to receive light reflected off said portion of the gear onto which the probe emits light.

4. The metering device according to claim 2, characterized in that the light source is located on a side of the gear opposite to the probe, said light source being adapted to emit light towards the probe such that the teeth of the gear at least partially block the optical path between said light source and said probe when passing through it.

5. The metering device according to claim 1, characterized in that the measuring unit comprises a signal transducer which is adapted to detect light received by said probe and to produce electrical signals corresponding to the intensity of the received light.

6. The metering device according to claim 3, characterized in that said signal transducer and said light source are located outside said housing.

7. The metering device according to claim 1, characterized in that said gear is a first gear and said metering device comprises one or more further gears which are respectively supported rotatably in said housing and inserted into said gear chamber in said housing such that a cavity for fluid transport is formed in between two adjacent teeth and said housing, said teeth engaging each other such that a cavity for fluid transport is formed in between said engaging teeth.

8. The metering device according to claim 6, characterized in that said one or more chamber inlets are located such that fluid may pass between two adjacent gears in the direction of rotation of said adjacent gears.

9. An apparatus for dispensing a fluid, in particular hot-melt adhesive, comprising

an applicator, said applicator comprising:

a base body comprising a fluid inlet, a fluid outlet and one or more fluid channels connecting said fluid inlet to said fluid outlet,

a nozzle for dispensing said fluid, said nozzle being coupled to said base body and in fluid communication with said fluid outlet, one or more electrically or pneumatically actuated valves for selecting, releasing or blocking the fluid flow through said one or more fluid channels and/or through said nozzle, and

a metering device for said fluid, comprising one or more fluid inlets connectable to a heating device and one or more outlets in fluid communication with said fluid inlet of said apparatus,

characterized in that the metering device is designed according to claim 1.

10. A remote metering apparatus for receiving and dispensing fluid, in particular hot-melt adhesive, comprising:

a base body comprising at least one fluid inlet as well as at least one fluid outlet, one or more fluid channels connecting said fluid outlet with said fluid inlet, at least one pump regulating the flow of said fluid,

a metering device for said fluid, said metering device comprising one or more fluid inlets connected to a heating device and one or more outlets communicating with said fluid inlet of said remote metering apparatus,

characterized in that said metering device is designed according to claim 1.