Patents Assigned to Ludwig Ehrhardt GmbH
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Patent number: 10940542Abstract: The invention relates to a clamping bushing (21) for clamping in a bore (3) of a component (2), in particular of a workpiece to be clamped, wherein the clamping bushing (21) is radially contracted in a relaxed state such that the clamping bushing (21) can be inserted into the bore (3) and pulled out of the bore (3), whereas the clamping bushing (21) is radially expanded in a stressed state such that the lateral surface of the clamping bushing (21) forms a mechanical connection to the inner wall of the bore (3). According to the invention, the mechanical connection between the lateral surface of the clamping bushing (21) and the inner wall of the bore (3) is positive-locking and consists of a threaded connection. The invention further relates to a corresponding clamping device (1).Type: GrantFiled: March 18, 2015Date of Patent: March 9, 2021Assignee: LUDWIG EHRHARDT GMBHInventor: Oliver Graulich
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Patent number: 9957995Abstract: The invention relates to a power-operated tightening nut (1) for axially tightening a fastening bolt, using an adjusting system (1) for adjusting the tightening force acting on the fastening bolt (2). The invention further provides an integrated display (24) for displaying the tightening force acting on the fastening bolt (2).Type: GrantFiled: September 26, 2014Date of Patent: May 1, 2018Assignee: LUDWIG EHRHARDT GMBHInventors: Nils Kolb, Thomas Willingshofer
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Publication number: 20180099382Abstract: The invention relates to a vise for clamping a workpiece with two clamping jaw holders, each for receiving a clamping jaw for clamping the workpiece between the two clamping jaws, a fixed lower part and a carriage guide for linearly displaceable guidance of at least one of the two clamping jaw holders, wherein the carriage guide has two guide bars which are fastened to the lower part. It is proposed that the guide bars of the carriage guide are fastened laterally to the lower part.Type: ApplicationFiled: January 22, 2016Publication date: April 12, 2018Applicant: LUDWIG EHRHARDT GMBHInventor: REINER HIPPENSTIEL
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Publication number: 20170136551Abstract: The invention relates to a clamping bushing (21) for clamping in a bore (3) of a component (2), in particular of a workpiece to be clamped, wherein the clamping bushing (21) is radially contracted in a relaxed state such that the clamping bushing (21) can be inserted into the bore (3) and pulled out of the bore (3), whereas the clamping bushing (21) is radially expanded in a stressed state such that the lateral surface of the clamping bushing (21) forms a mechanical connection to the inner wall of the bore (3). According to the invention, the mechanical connection between the lateral surface of the clamping bushing (21) and the inner wall of the bore (3) is positive-locking and consists of a threaded connection. The invention further relates to a corresponding clamping device (1).Type: ApplicationFiled: March 18, 2015Publication date: May 18, 2017Applicant: Ludwig Ehrhardt GMBHInventor: Oliver GRAULICH
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Patent number: 9279434Abstract: The invention relates to a pressure medium system, in particular a hydraulic system, having a fluid pump for delivering a drive fluid with a certain delivery flow rate and a certain fluid pressure, and having a control unit which switches the fluid pump on or off in order to set a predefined setpoint value of the fluid pressure, wherein the fluid pump exhibits an inertia-induced overrun when switched off, such that during the overrun of the fluid pump, the fluid pressure still rises while the fluid pump has already been switched off. It is proposed that, during the increase of the fluid pressure to the predefined setpoint value, the control unit switches the fluid pump off before the fluid pressure has reached the predefined setpoint value. The invention also includes a corresponding operating method.Type: GrantFiled: June 20, 2012Date of Patent: March 8, 2016Assignee: Ludwig Ehrhardt GmbHInventors: Winfried Ehrhardt, Georg Westerhagen
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Patent number: 9281775Abstract: The invention relates to a clamping device (1), for example swing tensioners (1), bracing elements, machine vises or block cylinders, with a movable clamping element (2) for clamping a workpiece with a defined clamping force, and with an electric motor (10) for mechanically driving the clamping element (2), also with a control unit that controls the electric motor (10). The invention provides that the control unit detects an electrical operating parameter of the electric motor (10) as a measure of the clamping force. The contact of the clamping element with the workpiece is detected in this manner. Subsequently, the electric motor (10) is then driven further by a defined number of revolutions, the number of revolutions after contact with the workpiece defining the clamping force. The invention further comprises a corresponding control method.Type: GrantFiled: September 19, 2012Date of Patent: March 8, 2016Assignee: Ludwig Ehrhardt GmbHInventors: Harald Kroell, Stefan Woerner, Nikolaus Heidt
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Publication number: 20140184106Abstract: The invention relates to a clamping device (1), for example swing tensioners (1), bracing elements, machine vises or block cylinders, with a movable clamping element (2) for clamping a workpiece with a defined clamping force, and with an electric motor (10) for mechanically driving the clamping element (2), also with a control unit that controls the electric motor (10). The invention provides that the control unit detects an electrical operating parameter of the electric motor (10) as a measure of the clamping force. The contact of the clamping element with the workpiece is detected in this manner. Subsequently, the electric motor (10) is then driven further by a defined number of revolutions, the number of revolutions after contact with the workpiece defining the clamping force. The invention further comprises a corresponding control method.Type: ApplicationFiled: September 19, 2012Publication date: July 3, 2014Applicant: Ludwig Ehrhardt GmbHInventors: Harald Kroell, Stefan Woerner, Nikolaus Heidt
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Publication number: 20140130484Abstract: The invention relates to a pressure medium system, in particular a hydraulic system, having a fluid pump for delivering a drive fluid with a certain delivery flow rate and a certain fluid pressure, and having a control unit which switches the fluid pump on or off in order to set a predefined setpoint value of the fluid pressure, wherein the fluid pump exhibits an inertia-induced overrun when switched off, such that during the overrun of the fluid pump, the fluid pressure still rises while the fluid pump has already been switched off. It is proposed that, during the increase of the fluid pressure to the predefined setpoint value, the control unit switches the fluid pump off before the fluid pressure has reached the predefined setpoint value. The invention also includes a corresponding operating method.Type: ApplicationFiled: June 20, 2012Publication date: May 15, 2014Applicant: Ludwig Ehrhardt GmbHInventors: Winfried Ehrhardt, Georg Westerhagen
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Patent number: 8220114Abstract: Disclosed herein is a pull-down fastening device for objects having bores, with a fastening unit which includes a fastening element. A pull-down fastening device is disclosed, with which the various fastening processes can, when necessary, be performed. For this purpose, the pull-down fastening device features a modular interchangeable fastening insert which insert includes a fastening element. Such pull-down fastening devices engage into bores of, for example, pallets or workpieces to be processed, for the purpose of interior fastening.Type: GrantFiled: August 11, 2008Date of Patent: July 17, 2012Assignee: Ludwig Ehrhardt GmbHInventors: Hendric Matzat, Klaus Richter
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Patent number: 7234704Abstract: The present invention pertains to a wiping and/or sealing element for sealing a piston (11) guided movably in a housing (10) with a seal held in a groove (21, 30). The present invention pertains, furthermore, to a process for sealing a movable piston (11) by means of a seal inserted into a groove (21, 30) and a clamping and/or support element with a piston (21), which is guided in a housing (10) such that it can be withdrawn and extended, wherein the piston (11) is sealed by means of a seal arranged in a groove (21). To achieve sealing of the piston (11) with a high sealing force for high liquid pressures at low friction, the wiping and/or sealing element according to the present invention as well as the clamping and/or support element according to the present invention are wherein the seal is a quad ring (22) with a square cross section.Type: GrantFiled: February 8, 2005Date of Patent: June 26, 2007Assignee: Ludwig Ehrhardt GmbHInventors: Adolf Lehr, Matthias Ehrhardt