Fiber metering device

Abstract

 The invention relates to a fiber metering device. This device comprises an inlet hopper for introducing the fibers to be metered, a conveyor belt provided with toothed combs for carding, separating and conveying the fibers to a fiber feeding chamber; a feeding chamber provided with a fiber outlet opening towards drive means for driving said fibers to the exterior; a centrifugal turbine for mechanically and pneumatically driving the fibers towards an outlet opening; a first spiked roller which is adjustable with respect to the conveyor belt for regulating the delivery or amount of fibers moved by said conveyor belt towards the feeding chamber and a second spiked roller for releasing, inside said feeding chamber, the fibers moved by the conveyor belt.

Description

Object of the Invention

[0001] The present invention relates to a fiber metering device, of the type comprising means for feeding the fibers to be metered towards pneumatic drive means which blow, inject or project the fibers.

Field of Application

[0002] This fiber metering device is especially intended for the construction field, although its use in any other sector which requires blowing fibers onto a surface, injecting the fibers between two walls or projecting the fibers towards auxiliary equipment connected to the outlet of the fiber metering device and in charge of supplying the fibers mixed with glues, adhesives or other products is not ruled out.

Background of the Invention

[0003] Various metering devices are known today which are intended to project natural or synthetic fibers, for example insulating fibers, comprising an inlet hopper, through which the product moves downwards by gravity towards a mechanical feeder formed by a rotating shaft provided with blades for supplying fibers towards a metering element associated with a drive conduit by means of pressurized air.

[0004] In some cases, this metering element is formed by a rotary valve which, by means of radial blades rotating inside the cylindrical body of the valve, gradually deposit them inside a drive conduit of pressurized air in charge of projecting towards the exterior.

[0005] In other cases, for example in patent ES 2 051 157 B1, the metering element is a worm screw moving the fibers supplied by the mechanical feeder towards a drive conduit fed with pressurized air.

[0006] These fiber metering devices have problems for metering fibers when the latter are supplied in more or less compacted bundles since the blades of the mechanical feeder do not perform a correct separation and fluffing of the fibers, moving layers of fibers towards the metering element, which causes jams in said metering element, both if said metering element is a worm screw and if it is a rotary valve. These jams are determined by the trapping of the fibers between the rotating element and the casing or envelopment of the metering element (worm screw or rotary valve).

[0007] These metering devices require the joint use of the mechanical metering element in charge of moving the fibers and of a pneumatic element in charge of supplying the pressurized air necessary for the drive thereof, which involves a certain mechanical complexity and increases the final cost of the metering device.

[0008] A second drawback of these fiber metering devices is the impossibility of varying the delivery or amount of fiber to be supplied without the risk of jams and maintaining the work regime of the machine constant, which is especially important taking into account that the metering device can work with fibers of different textures, densities and having a different behavior while they are handled by the feeder and by the metering element.

Description of the Invention

[0009] The fiber metering device object of the invention has been designed to solve the mentioned problems, which device has constructive particularities aimed at achieving a separation and fluffing of the fibers by the mechanical feeder in charge of conveying them towards the drive means for the purpose of preventing subsequent jams.

[0010] Another objective of the invention is to allow a regulation of the delivery or amount of fibers to be supplied without needing to vary the work regime of the metering device, adapting the delivery of fibers to be supplied according to the type of behavior of the fibers to be used in each case.

[0011] Another objective of the invention is the use of drive means which simultaneously drive the fibers mechanically and pneumatically towards the outside of the metering device, avoiding the use of independent means for the mechanical metering and for the pneumatic drive of the fibers, to achieve a simpler construction preventing the fibers from being jammed therein.

[0012] Another objective of the invention is to make the inlet hopper independent from the area for feeding fibers to the drive means, such that the load of fibers introduced in the inlet hopper cannot affect the amount or delivery of fibers supplied by the metering device.

[0013] To that end, and according to the invention, the fiber metering device comprises:

• a conveyor belt provided with toothed combs for carding, separating and conveying the fibers from the inlet hopper to a fiber feeding chamber independent from the inlet hopper;
• a feeding chamber provided with a fiber outlet opening towards drive means for driving said fibers to the exterior
• a centrifugal turbine for mechanically and pneumatically driving the fibers in a simultaneous manner towards an outlet opening of the metering device,
• a first spiked roller arranged inside the inlet hopper and assembled on movable supports to vary the separation thereof with respect to the conveyor belt and to regulate the delivery or amount of fibers moved by said conveyor belt towards the feeding chamber,
• a second spiked roller arranged inside the feeding chamber to release, inside said feeding chamber, the fibers moved by the conveyor belt.

[0014] According to the invention, the conveyor belt and the spiked rollers are connected to a drive motor by means of mechanical transmissions causing the rotation thereof.

[0015] In an embodiment of the invention, the first spiked roller rotates in a direction opposite to the advance of the conveyor belt, which allows the first roller, once it is arranged at the desired distance from the conveyor belt, to prevent said belt from being able to convey a delivery or amount of fibers greater than that passing through the space comprised between said conveyor belt and the first spiked roller.

[0016] In turn, the second spiked roller, located inside the feeding chamber, removes the fibers from the conveyor belt and releases them in the feeding chamber.

[0017] It can be easily understood that the action of the toothed combs of the conveyor belt literally pull off the fibers from the bundles of fibers introduced in the inlet hopper, causing a separation and fluffing of the fibers, to which the second spiked roller in charge of removing the fibers from the conveyor belt contribute.

[0018] This separation and fluffing of the fibers considerably favors their subsequent mechanical and pneumatic drive by the centrifugal turbine.

[0019] In an embodiment of the invention, said centrifugal turbine is arranged in a horizontal plane, below the horizontal chamber, and has at the upper part an axial opening for the entrance of the fibers coming from said feeding chamber, by the action of gravity and by the suction effect caused by the rotation of the turbine.

[0020] The combined mechanical and pneumatic action of the centrifugal turbine on the fibers prevents them from being jammed inside the turbine and favors their drive towards the tangential outlet opening, through which they are ejected together with the pressurized air towards the outside of the metering device.

[0021] The efficiency of this device allows pneumatically conveying the fibers through the inside of a hose connected to the outlet opening, to a distance of about forty meters in length.

Description of the Drawings

[0022] To complement the description which is being made and for the purpose of aiding to better understand the features of the invention, a set of drawings is attached to the present specification, in which the following has been depicted with an illustrative and non-limiting character:

• Figure 1 shows an elevational view of an embodiment of the fiber metering device sectioned by a vertical plane.
• Figure 2 shows an elevational view of the machine, in which the drive means of the conveyor belt and of the toothed combs can be observed, only the contour of a protective cover for said drive means having been depicted by means of dotted lines.

Preferred Embodiment of the Invention

[0023] As can be observed in the embodiment shown in the attached figures, the fiber metering device comprises an inlet hopper (1) for introducing the fibers to be metered, in bulk form or in the form of compacted bundles,; a conveyor belt (2) provided with toothed combs (21) for conducting the fibers from the inlet hopper (1) to a feeding chamber (3), from which they access drive means, formed by a centrifugal turbine (4) driving them mechanically and pneumatically towards the outlet opening (5).

[0024] In the inlet hopper (1) there is arranged a first spiked roller (6) arranged parallel to the conveyor belt (2) and assembled on movable supports (61) which allow moving it closer to and away from the conveyor belt, for the purpose of regulating the delivery or amount of fibers moved by said conveyor belt (2) towards the feeding chamber (3).

[0025] In the feeding chamber (3) there is arranged a second spiked roller (7) in charge of removing the fibers from the conveyor belt and of releasing them inside said feeding chamber, from where they are driven by the centrifugal turbine towards the outlet opening.

[0026] The conveyor belt (2) and the spiked rollers (6, 7) are driven by the motor (8) by means of mechanical transmissions depicted in this case by the respective pulleys and the belts (81, 82). In a preferred embodiment the spiked roller (6) rotates in a direction opposite to the conveyor belt (2) to prevent the passage towards the feeding chamber of the excess of product driven by the conveyor belt (2) and to therefore regulate the delivery or amount of fibers moved by said conveyor belt (2).

[0027] The centrifugal turbine (4), provided with the corresponding motor (41), is arranged in a horizontal plane below the feeding chamber (3) and has at the upper part an axial opening (42) for the entrance of the fibers coming from said feeding chamber (3) and a tangential outlet connected to the outlet opening (2) of the fiber metering device.

[0028] Having sufficiently described the nature of the invention, as well as a preferred embodiment, it is stated for the relevant purposes that the materials, shape, size and arrangement of the described elements may be modified, provided that this does not entail an alteration of the essential features of the invention which are claimed below.

Claims

1. A fiber metering device, of the type comprising an inlet hopper for introducing the fibers to be metered in bulk form or in the form of compacted bundles, a mechanical feeder of the fibers introduced in the feeding hopper and drive means for driving the fibers to the exterior; characterized in that it comprises:

- a conveyor belt provided with toothed combs for carding, separating and conveying the fibers from the inlet hopper to a fiber feeding chamber independent from the inlet hopper;

- a feeding chamber provided with a fiber outlet opening towards drive means for driving said fibers to the exterior

- a centrifugal turbine for mechanically and pneumatically driving the fibers in a simultaneous manner towards an outlet opening of the metering device,

- a first spiked roller arranged inside the inlet hopper and assembled on movable supports to vary the separation thereof with respect to the conveyor belt and to regulate the delivery or amount of fibers moved by said conveyor belt towards the feeding chamber,

- a second spiked roller arranged inside the feeding chamber to release, inside said feeding chamber, the fibers moved by the conveyor belt.

2. The device according to claim 1, characterized in that the conveyor belt and the spiked rollers are connected to a drive motor by means of mechanical transmissions causing the rotation thereof.

3. The device according to claim 1, characterized in that the centrifugal turbine is arranged in a horizontal plane, below the feeding chamber, and has at the upper part an axial opening for the entrance of the fibers coming from said feeding chamber.

Drawing