Patent Description:
The invention proposed here is used in the food industry, in particular in the dairy sector, or in the chemical, pharmaceutical or cosmetic industry. The invention can also be used in manufacturing areas where homogenization is a step of the production process.

Consider, for example, the production of carbon-based nanostructured materials, such as graphene and carbon nanotubes or cellular breakdown of yeasts, algae, or microorganisms for the production of intracellular material.

As it is well-known, apparatus for homogenising fluids crush the particles, reducing their dimensions to a minimum and make the dimensions of the particles uniform, thus reducing variation of distribution of the dimensions of the particles.

Said homogenising apparatus, also in the different embodiments so far known, comprise a high-pressure pump and a homogenising valve. The homogenising valve comprises a first chamber receiving the fluid at high pressure from the pump delivery and a second chamber capable of supplying outgoing homogenised fluid at low pressure. The homogenising action is obtained by forcing the fluid to pass through an interspace or gap with reduced dimensions afforded between the first and the second chamber. The gap is defined by a passage head integrally joined to the valve body and by an impact head axially mobile with respect to the passage head.

The fluid coming from the inlet presses on a surface of the impact head exerting on it a pressure which tends to widen the gap.

A pusher capable of contrasting the pressure of the fluid in an axial direction is applied to the impact head. The dimension of the gap is controlled by acting directly on the pusher as a function of the valve flow rate and pressure operating values.

As already indicated above, the fluid loses pressure by passing through the gap and is simultaneously accelerated, thus allowing fragmentation of the particles in suspension.

In order to optimise the energy used in the homogenisation process, over recent years, the Applicant has developed homogenising valves in which the first and the second chamber have an annular shape. Said solutions are described in European patent <CIT> and in <CIT> in the name of the Applicant.

The annular configuration of the two chambers allows the fluid at high pressure to press on an annular surface of the impact head, thus allowing operation with a gap of reduced dimensions with the same energy applied. One limit of the solution just described lies in the form and position of the pusher acting on the impact head. The pusher consists in a shaft integrally fixed to the impact head and located in the upper part of the homogenizing valve.

Under the pushing action of the shaft, the impact head is moved downwards, that means towards the gap.

Actuating the impact head far from the working area, which is the gap, introduces tolerances that may result in an undesired mechanical misalignment. The higher is the misalignment, the worse is the performance of the homogenizing valve.

Documents <CIT> and <CIT> disclose guiding devices according to the preamble of claim <NUM>.

In this context, the object of the present invention is to provide a guiding device for guiding an impact head and a homogenizing valve, which overcome the problems of the prior art cited above.

In particular, the object of the present invention is to propose a guiding device for guiding an impact head in which the impact head may be actuated in a more accurate and reliable way, avoiding or at least decreasing the risks of mechanical misalignments.

Another object of the present invention is to propose a guiding device for guiding an impact head wherein the useful lifetime of the impact head is increased over the prior art solutions.

The stated technical task and specified aims are substantially achieved by a guiding device for guiding an impact head of a homogenizing valve according to claim <NUM>.

According to an aspect of the invention, the solid body is made of a single piece.

Preferably, the core has a substantially hollow cylindrical shape.

More preferably, the core has an annular protrusion at one end so as to retain the sleeve.

In particular, the annular protrusion projects inward towards the internal cavity.

According to one aspect of the invention, the through-holes are arranged around the core.

In particular, each of said through-holes has an arcuated development. The stated technical task and specified aims are substantially achieved by a homogenizing valve comprising:.

Preferably, the impact head is made of one of the following materials: tungsten carbide, ceramic, boron nitride, silicon carbide, silicon nitride.

Further characteristics and advantages of the present invention will more fully emerge from the non-limiting description of a preferred but not exclusive embodiment of a guiding device for guiding an impact head and of a homogenizing valve comprising said guiding device, as illustrated in the accompanying drawings in which:.

With reference to the figures, reference numeral <NUM> denotes a guiding device for guiding an impact head <NUM> of a homogenizing valve <NUM>.

In this context, an impact head <NUM> is also called striking head.

The guiding device <NUM> comprises a solid body <NUM> having a cylindrical symmetry and having an internal cavity <NUM> passing through the solid body <NUM>. The internal cavity <NUM> develops according to an axis of symmetry A-A of the solid body <NUM>.

In particular, the internal cavity <NUM> is coaxial with the solid body <NUM>.

Preferably, the solid body <NUM> is made of a single piece.

For example, the solid body <NUM> is made of steel.

Alternatively, the solid body <NUM> is made of a metal material.

The guiding device <NUM> further comprises a sleeve <NUM> fitted within the internal cavity <NUM> of the solid body <NUM> for receiving the impact head <NUM>.

The sleeve <NUM> is made by a plastic material.

In particular, the sleeve <NUM> is made by PTFE.

The solid body <NUM> has a plurality of passages <NUM> that are obtained for allowing the passage of a fluid.

According to the invention, illustrated in <FIG>. the solid body <NUM> comprises a case <NUM> and a core <NUM> located inside the case <NUM>. The case <NUM> and the core <NUM> are integrally connected. The case <NUM> and the core <NUM> are connected by a plurality of connecting elements <NUM>.

The internal cavity <NUM> is delimited by the core <NUM>.

The passages <NUM> are through-holes <NUM> obtained between the case <NUM> and the core <NUM>. The through-holes <NUM> are separated by the connecting elements <NUM> that connect the case <NUM> to the core <NUM>.

The core <NUM> has a substantially hollow cylindrical shape.

In particular, the core <NUM> has an annular protrusion <NUM> at one end so as to retain the sleeve <NUM>.

The annular protrusion <NUM> projects inward towards the hollow of the core <NUM>. In other words, the annular protrusion <NUM> projects towards the internal cavity <NUM>.

Preferably, the through-holes <NUM> are arranged around the core <NUM>.

In particular, each through-hole <NUM> has an arcuated development.

For example, the through-holes <NUM> are four and are distributed circumferentially so as to be arranged around the core <NUM>.

Preferably, the through-holes <NUM> have all the same dimensions and shape and are equally spaced.

In an embodiment, the case <NUM> comprises a first portion <NUM> having a first external diameter and a second portion <NUM> having a second external diameter that is lower than the first external diameter.

Preferably, the first portion <NUM> and the second portion <NUM> have a substantially hollow cylindrical shape.

The second portion <NUM> is integral and coaxial with the first portion <NUM> according to the axis of symmetry A-A.

According to an aspect of the invention, the second portion <NUM> originates from the first portion <NUM>.

In particular, the solid body <NUM> comprises an external surface <NUM> having an annular step 8a that externally connects the first portion <NUM> to the second portion <NUM>.

In particular, the annular step 8a is defined by narrowing of the diameter passing from the first portion <NUM> to the second portion <NUM>.

According to an embodiment which is not part of the claimed invention, illustrated in <FIG>, the passages <NUM> are grooves <NUM> obtained in the solid body <NUM>.

In this context, the grooves <NUM> are blind apertures.

In this embodiment, the solid body <NUM> comprises a first element <NUM> and a second element <NUM> that are integrally connected and coaxial.

Preferably, the first element <NUM> and the second element <NUM> have a substantially hollow cylindrical shape.

They are coaxial according to the axis of symmetry A-A of the solid body <NUM>.

In particular, the second element <NUM> originates from the first element <NUM>. The first element <NUM> has an external diameter that is higher than the external diameter of the second element <NUM>.

Preferably, the first element <NUM> and the second element <NUM> are connected by an annular step 28a that is defined by narrowing of the diameter passing from the first element <NUM> to the second element <NUM>.

In this embodiment, the grooves <NUM> are obtained in the second element <NUM> of the solid body <NUM>.

In particular, the grooves <NUM> are obtained on an external lateral surface of the second element <NUM>.

Preferably, the grooves <NUM> are equally spaced according to a circumferential development of the second element <NUM>.

For example, the grooves <NUM> are four.

In this embodiment, the solid body <NUM> has an internal annular protrusion <NUM> so as to retain the sleeve <NUM> at one end.

The annular protrusion <NUM> of the solid body <NUM> projects inward towards the cavity <NUM>.

Preferably, the guiding device <NUM> further comprises a stop element <NUM> operatively active on another end of the sleeve <NUM> that is opposite to the end close to the protrusion <NUM>.

The stop element <NUM> is used to maintain the sleeve <NUM> fitted inside the cavity <NUM> of the solid body <NUM>.

The stop element <NUM> is inserted inside an internal annular groove <NUM> obtained in the second element <NUM>.

Preferably, the stop element <NUM> is a seeger.

The seeger <NUM> is an annular stop element with a cut <NUM>, that is preferably made of an elastic material. For example, the seeger <NUM> is made of plastic, in particular PEEK.

The seeger <NUM> may be fitted easily inside the internal annular groove <NUM> due to its elasticity and the presence of the cut <NUM>. Number <NUM> identifies a homogenizing valve comprising a valve body <NUM> defining a through-hole having axial development with respect to the valve body <NUM>.

The homogenizing valve <NUM> comprises a shaft <NUM> housed in the through-hole defined by the valve body <NUM>.

The homogenizing valve <NUM> has a gap wherein a fluid to be homogenized is accelerated.

The gap is defined by a passage head <NUM> that is integrally connected to the valve body <NUM> and an impact head <NUM> that is integrally connected to the shaft <NUM>.

The homogenizing valve <NUM> has an inlet for a fluid at high pressure and an outlet for homogenized fluid at low pressure.

The homogenizing valve <NUM> comprises a guiding device <NUM> according to the proposed invention.

According to one aspect of the invention, the solid body <NUM> of the guiding device <NUM> has a recess for supporting the valve body <NUM>.

In particular, the valve body <NUM> urges on the annular step 8a of the solid body <NUM>.

The impact head <NUM> is received by the sleeve <NUM> of the guiding device <NUM>.

The impact head <NUM> is actuated by a shaft <NUM> that is integrally connected to the impact head <NUM>.

In particular, the shaft <NUM> is located in an upper part of the homogenizing valve <NUM>.

Under the pushing action of the shaft <NUM>, the impact head <NUM> is moved downwards, that means towards the gap that receives the fluid from the inlet and delivers it to the outlet.

The impact head <NUM>, being fitted inside the sleeve <NUM> is guided towards the passage head <NUM>.

The guiding device <NUM> allows the passage of the fluid thanks to the passages <NUM>, that are the through-holes <NUM>.

According to an aspect of the invention, the impact head <NUM> is made of one of the following materials: tungsten carbide, ceramic, boron nitride, silicon carbide, silicon nitride.

The characteristics of the guiding device for guiding an impact head and of a homogenizing valve comprising said guiding device according to the present invention emerge clearly from the above description, as do the advantages.

In particular, the guiding device is designed to guide the impact head by embracing it, thus reducing tolerances and misalignments.

In addition, the impact head may be actuated in a more accurate and reliable way since the guiding device acts on the impact head close to the working area, i.e., the gap of the homogenizing valve. Providing a guiding device close to the working area is feasible thanks to the through- holes that allow the passage of the fluid.

With the claimed invention, the lifetime of the impact head is increased with respect to the known solutions.

Claim 1:
A guiding device (<NUM>) for guiding an impact head (<NUM>) of a homogenizing valve (<NUM>), said guiding device (<NUM>) comprising:
- a solid body (<NUM>) having a cylindrical symmetry and having an internal cavity (<NUM>) passing through the solid body (<NUM>), said internal cavity (<NUM>) developing according to an axis of symmetry (A-A) of the solid body (<NUM>), said solid body (<NUM>) having a plurality of passages (<NUM>) that are obtained for allowing the passage of a fluid, said solid body (<NUM>) comprising a case (<NUM>) and a core (<NUM>) that are integrally connected, the internal cavity (<NUM>) being delimited by the core (<NUM>);
- a sleeve (<NUM>) fitted within the internal cavity (<NUM>) of the solid body (<NUM>) for receiving the impact head (<NUM>),
characterized in that the passages of the plurality of passages (<NUM>) are through-holes (<NUM>) obtained between the case (<NUM>) and the core (<NUM>), said through-holes (<NUM>) being separated by connecting elements (<NUM>) that connect the core (<NUM>) to the case (<NUM>).