Patents by Inventor Martin Theodoor de Groot

Martin Theodoor de Groot has filed for patents to protect the following inventions. This listing includes patent applications that are pending as well as patents that have already been granted by the United States Patent and Trademark Office (USPTO).

  • Patent number: 11858182
    Abstract: A press (10) for manufacturing a sandwich panel comprises a first and second press plate (12; 14) that are movable with respect to one another. The press (10) has a fluid circulation loop for heating and cooling the press plates (12; 14). The fluid circulation N loop comprises a heater (22) for generating a hot fluid connected to a fluid supply conduit (24) in fluid communication with an inlet (18) of at least one internal flow channel (16) in each press plate (12; 14) and connected to a fluid return conduit (26) in fluid communication with an outlet (20) of the at least one internal flow channel (16). The fluid circulation loop is also provided with a controlled expansion valve (34) for cooling by conversion of hot pressurized water into steam, and a water source (38) for slow cooling.
    Type: Grant
    Filed: December 2, 2019
    Date of Patent: January 2, 2024
    Assignee: FITS HOLDING B.V.
    Inventor: Martin Theodoor De Groot
  • Publication number: 20230116066
    Abstract: The invention relates to a method of manufacturing a sandwich panel comprises the steps of: a) providing a plate-shaped assembly of a first cover part and a second cover part and between these cover parts a core part of a thermoplastic material containing a physical blowing agent, b) heating the assembly resulting from step a) under pressure between press tools in a press to a foaming temperature below the glass transition temperature of the thermoplastic material in the core part, thereby effecting adhesion of the foamed core part to the first and second cover parts c) foaming the thermoplastic material in the core part under pressure and at the foaming temperature wherein the spacing between the press tools is increased; d) a cooling step of cooling the foamed sandwich panel resulting from step c), while the sandwich panel is maintained under pressure between the press tools; e) removing the thus cooled sandwich panel from the press; and f) drying the sandwich panel thus obtained; wherein the cooling step d
    Type: Application
    Filed: December 9, 2022
    Publication date: April 13, 2023
    Inventor: Martin Theodoor de Groot
  • Patent number: 11524431
    Abstract: The invention relates to a method of manufacturing a sandwich panel comprises the steps of: a) providing a plate-shaped assembly of a first cover part and a second cover part and between these cover parts a core part of a thermoplastic material containing a physical blowing agent, b) heating the assembly resulting from step a) under pressure between press tools in a press to a foaming temperature below the glass transition temperature of the thermoplastic material in the core part, thereby effecting adhesion of the foamed core part to the first and second cover parts c) foaming the thermoplastic material in the core part under pressure and at the foaming temperature wherein the spacing between the press tools is increased; d) a cooling step of cooling the foamed sandwich panel resulting from step c), while the sandwich panel is maintained under pressure between the press tools; e) removing the thus cooled sandwich panel from the press; and f) drying the sandwich panel thus obtained; wherein the cooling
    Type: Grant
    Filed: July 7, 2016
    Date of Patent: December 13, 2022
    Assignee: FITS HOLDING B.V.
    Inventor: Martin Theodoor de Groot
  • Publication number: 20220097265
    Abstract: A press (10) for manufacturing a sandwich panel comprises a first and second press plate (12; 14) that are movable with respect to one another. The press (10) has a fluid circulation loop for heating and cooling the press plates(12; 14). The fluid circulation N loop comprises a heater (22) for generating a hot fluid connected to a fluid supply conduit(24)in fluid communication with an inlet(18) of at least one internal flow channel (16) in each press plate (12; 14) and connected to a fluid return conduit(26) in fluid communication with an outlet (20) of the at least one internal flow channel(16). The fluid circulation loop is also provided with a controlled expansion valve (34) for cooling by conversion of hot pressurized water into steam, and a water source (38) for slow cooling.
    Type: Application
    Filed: December 2, 2019
    Publication date: March 31, 2022
    Inventor: Martin Theodoor DE GROOT
  • Patent number: 10737416
    Abstract: The invention relates to a method of manufacturing a sandwich panel having an asymmetrical configuration in the thickness direction.
    Type: Grant
    Filed: July 7, 2016
    Date of Patent: August 11, 2020
    Assignee: FITS HOLDING B.V.
    Inventor: Martin Theodoor de Groot
  • Patent number: 10471634
    Abstract: A method and device for manufacturing a sandwich structure comprising at least one foam layer of a first thermoplastic comprising a chemical blowing agent and two cover layers. The decomposition temperature of the chemical blowing agent is higher than the melting point or range of the first thermoplastic. The method comprises a series of steps performed on an advancing starting structure including heating under pressure in order to cause decomposition of the blowing agent, intermediate cooling, foaming at a constant volume and further cooling.
    Type: Grant
    Filed: October 28, 2014
    Date of Patent: November 12, 2019
    Assignee: FITS HOLDING B.V.
    Inventor: Martin Theodoor De Groot
  • Patent number: 10369726
    Abstract: A method and device for manufacturing a sandwich structure comprising at least one foam layer of a first thermoplastic comprising a chemical blowing agent and two fibre-reinforced cover layers of a second thermoplastic. The decomposition temperature of the chemical blowing agent is higher than the melting point or range of the first thermoplastic. The method comprises a series of steps performed on a starting structure including heating under pressure in order to cause decomposition of the blowing agent, cooling, foaming and further cooling in contact with the press tools.
    Type: Grant
    Filed: October 28, 2014
    Date of Patent: August 6, 2019
    Assignee: FITS HOLDING B.V.
    Inventor: Martin Theodoor De Groot
  • Publication number: 20190077058
    Abstract: The invention relates to a method of manufacturing a sandwich panel having an asymmetrical configuration in the thickness direction.
    Type: Application
    Filed: July 7, 2016
    Publication date: March 14, 2019
    Inventor: Martin Theodoor de Groot
  • Publication number: 20180194044
    Abstract: The invention relates to a method of manufacturing a sandwich panel comprises the steps of: a) providing a plate-shaped assembly of a first cover part and a second cover part and between these cover parts a core part of a thermoplastic material containing a physical blowing agent, b) heating the assembly resulting from step a) under pressure between press tools in a press to a foaming temperature below the glass transition temperature of the thermoplastic material in the core part, thereby effecting adhesion of the foamed core part to the first and second cover parts c) foaming the thermoplastic material in the core part under pressure and at the foaming temperature wherein the spacing between the press tools is increased; d) a cooling step of cooling the foamed sandwich panel resulting from step c), while the sandwich panel is maintained under pressure between the press tools; e) removing the thus cooled sandwich panel from the press; and f) drying the sandwich panel thus obtained; wherein the cooling
    Type: Application
    Filed: July 7, 2016
    Publication date: July 12, 2018
    Inventor: Martin Theodoor de Groot
  • Publication number: 20160271846
    Abstract: A method and device for manufacturing a sandwich structure comprising at least one foam layer of a first thermoplastic comprising a chemical blowing agent and two fibre-reinforced cover layers of a second thermoplastic. The decomposition temperature of the chemical blowing agent is higher than the melting point or range of the first thermoplastic. The method comprises a series of steps performed on a starting structure including heating under pressure in order to cause decomposition of the blowing agent, cooling, foaming and further cooling in contact with the press tools.
    Type: Application
    Filed: October 28, 2014
    Publication date: September 22, 2016
    Inventor: Martin Theodoor DE GROOT
  • Publication number: 20160250784
    Abstract: A method and device for manufacturing a sandwich structure comprising at least one foam layer of a first thermoplastic comprising a chemical blowing agent and two cover layers. The decomposition temperature of the chemical blowing agent is higher than the melting point or range of the first thermoplastic. The method comprises a series of steps performed on an advancing starting structure including heating under pressure in order to cause decomposition of the blowing agent, intermediate cooling, foaming at a constant volume and further cooling.
    Type: Application
    Filed: October 28, 2014
    Publication date: September 1, 2016
    Inventor: Martin Theodoor DE GROOT
  • Patent number: 9242425
    Abstract: A sandwich structure based on a composite panel made of a thermoplastic core layer connected to at least one fiber-reinforced thermoplastic layer, in particular in-situ manufactured sandwich panels, comprises a thermoplastic core, which is arranged between two cover layers, in which the core is reinforced with fiber-reinforced thermoplastic reinforcing ribs which extend between the cover layers. Preferred methods for the manufacture are also described.
    Type: Grant
    Filed: December 22, 2014
    Date of Patent: January 26, 2016
    Assignee: FITS Holding B.V.
    Inventor: Martin Theodoor de Groot
  • Publication number: 20150118440
    Abstract: A sandwich structure based on a composite panel made of a thermoplastic core layer connected to at least one fiber-reinforced thermoplastic layer, in particular in-situ manufactured sandwich panels, comprises a thermoplastic core, which is arranged between two cover layers, in which the core is reinforced with fiber-reinforced thermoplastic reinforcing ribs which extend between the cover layers. Preferred methods for the manufacture are also described.
    Type: Application
    Filed: December 22, 2014
    Publication date: April 30, 2015
    Inventor: Martin Theodoor de Groot
  • Patent number: 8932422
    Abstract: A sandwich structure based on a composite panel made of a thermoplastic core layer connected to at least one fiber-reinforced thermoplastic layer, in particular in-situ manufactured sandwich panels, comprises a thermoplastic core, which is arranged between two cover layers, in which the core is reinforced with fiber-reinforced thermoplastic reinforcing ribs which extend between the cover layers. Preferred methods for the manufacture are also described.
    Type: Grant
    Filed: May 7, 2007
    Date of Patent: January 13, 2015
    Assignee: FITS Holding B.V.
    Inventor: Martin Theodoor de Groot
  • Patent number: 8182625
    Abstract: The invention relates to a method of manufacturing a sandwich panel (10). Such a sandwich panel consists of a foamed core layer (12) and at least one thermoplastic cover layer (14). The sandwich panel is made by in situ foaming. In a first assembling step a core web, comprising at least one sheet of a thermoplastic material (12) containing an amount of a suitable physical blowing agent is positioned between two cover layers (14). The assembly of core web and cover layers is arranged between two press plates. Due to heat and pressure applied in a subsequent foaming step, foaming of the core web and effective bonding thereof to the cover layers is achieved. Subsequently the foamed assembly is allowed to cool down. Remaining physical blowing agent is removed during a subsequent drying step at elevated temperature while the outflow of physical blowing agent via the peripheral edges of the panel (10) is restricted, e.g. by taping (24) or clamping by clamps (16, 20).
    Type: Grant
    Filed: January 24, 2006
    Date of Patent: May 22, 2012
    Assignee: FITS Holdiing B.V.
    Inventor: Martin Theodoor de Groot
  • Patent number: 8110133
    Abstract: A method for producing a composite construction element is disclosed. In one embodiment, the method includes the steps of: a) providing a composite construction element, which comprises a thermoplastic core layer between two fiber-reinforced thermoplastic cover layers; b) providing one or more interruptions in a fiber-reinforced thermoplastic cover layer of the panel; c) positioning a fiber-reinforced thermoplastic reinforcing layer over and/or near the interruption; d) deforming at least the edges situated along the interruption and, if desired, the thermoplastic reinforcing layer, preferably while simultaneously locally compacting the core layer, so that a thermoplastic construction element having a recess which is delimited by fiber-reinforced thermoplastic walls is obtained.
    Type: Grant
    Filed: May 7, 2007
    Date of Patent: February 7, 2012
    Assignee: FITS Holding B.V.
    Inventor: Martin Theodoor de Groot
  • Patent number: 7807093
    Abstract: A method for arranging a thermoplastic insert unit (2) in a thermoplastic sandwich product (1) having at least one planar or virtually planar section by the application of ultrasonic energy (6, 8). A thermoplastic sandwich product (1) comprises at least one fiber-reinforced thermoplastic covering layer (7) and a thermoplastic core which is not completely solid (8). Examples of thermoplastic sandwich products include: a flat plate, a slightly curved product, a folded product, etc. The production of a recess in the surface of the thermoplastic sandwich product, with the plastic insert unit being welded into the recess.
    Type: Grant
    Filed: October 15, 2004
    Date of Patent: October 5, 2010
    Assignee: Fits Holding B.V.
    Inventor: Martin Theodoor de Groot
  • Publication number: 20090297758
    Abstract: A sandwich structure based on a composite panel made of a thermoplastic core layer connected to at least one fiber-reinforced thermoplastic layer, in particular in-situ manufactured sandwich panels, comprises a thermoplastic core, which is arranged between two cover layers, in which the core is reinforced with fiber-reinforced thermoplastic reinforcing ribs which extend between the cover layers. Preferred methods for the manufacture are also described.
    Type: Application
    Filed: May 7, 2007
    Publication date: December 3, 2009
    Applicant: FITS HOLDING B.V.
    Inventor: Martin Theodoor de Groot
  • Publication number: 20090115097
    Abstract: A method for producing a composite construction element comprises the steps of: a) providing a composite construction element, which comprises a thermoplastic core layer between two fiber-reinforced thermoplastic cover layers; b) providing one or more interruptions in a fiber-reinforced thermoplastic cover layer of the panel; c) positioning a fiber-reinforced thermoplastic reinforcing layer over and/or near the interruption; d) deforming situated along the interruption and, if desired, the thermoplastic reinforcing layer, preferably while simultaneously locally compacting the core layer, so that a thermoplastic construction element having a recess which is delimited by fiber-reinforced thermoplastic walls is obtained.
    Type: Application
    Filed: May 7, 2007
    Publication date: May 7, 2009
    Applicant: FITS HOLDING B.V.
    Inventor: Martin Theodoor de Groot