Assembly method for joining the telescopic rod part of a VCR connecting rod

Patent metadata

Field	Value
Publication number	US-11047298-B2
Application number	US-201916593779-A
Country	US
Kind code	B2
Filing date	Oct 4, 2019
Priority date	Oct 8, 2018
Publication date	Jun 29, 2021
Grant date	Jun 29, 2021

Abstract

An assembly method for joining a telescopic rod part of a length-adjustable connecting rod, the method includes the following steps: providing a first section of the telescopic rod part, the first section comprising a connecting-rod eye and having a connection thread, providing a second section of the telescopic rod part, the second section comprising the piston rod, to which a piston is fixedly connected, and having a connection thread, wherein the second section has already arranged thereon at least sealing and/or supporting and/or closing elements, which are to be secured to the second section and which are to be mounted onto the piston rod and the piston, respectively, from the side of the associated connection thread, providing a tool for establishing a sufficiently strong frictional engagement with the piston rod and the piston, respectively, by means of form-fit clamping, establishing a sufficiently strong frictional engagement with the second section of the telescopic rod part by means of the tool, screw fastening the first section of the telescopic rod part to the second section of the telescopic rod part by means of the respective connection threads, applying the necessary tightening torque between the first section of the telescopic rod part and the second section of the telescopic rod part by means of the attached tool. In addition, the present invention relates to the use of a telescopic rod part of a VCR connecting rod in such a method.

First claim

The invention claimed is:

1. An assembly method for joining a telescopic rod part of a length-adjustable connecting rod, the method comprising the following steps:
providing a first section of the telescopic rod part, the first section comprising a connecting-rod eye and having a connection thread,
providing a second section of the telescopic rod part, the second section comprising a piston rod, to which a piston is fixedly connected, and having a connection thread, wherein the second section of the telescopic rod part has already arranged thereon at least sealing and/or supporting and/or closing elements, which are to be secured to the second section and which are to be mounted onto the piston rod and the piston, respectively, from the side of the associated connection thread,
providing a tool for establishing a sufficiently strong frictional engagement with the piston rod and the piston, respectively, by means of form-fit clamping,
establishing a sufficiently strong frictional engagement with the second section of the telescopic rod part by means of the tool,
screw fastening the first section of the telescopic rod part to the second section of the telescopic rod part by means of the respective connection threads, and
applying the necessary tightening torque between the first section of the telescopic rod part and the second section of the telescopic rod part by means of the attached tool.

2. The assembly method according to claim 1 , wherein the piston on the second section of the telescopic rod part comprises, on the side facing away from the connection thread, a shoulder for attaching a sealing element and/or a supporting element and that the frictional engagement is established with the shoulder.

3. The assembly method according to claim 2 , wherein the tool provided is a collet chuck and that the frictional engagement with the shoulder is established by means of the collet chuck, wherein, preferably, the frictional engagement between the shoulder and the tool is released, when the necessary tightening torque has been applied, and a sealing element and/or a supporting element is mounted on the shoulder after the latter has been released.

4. The assembly method according to claim 1 , wherein the tool provided is a tension clamp, the tensioning width of this tension clamp corresponding at most to the available clamping width on the second section of the telescopic rod part, wherein, preferably, at least one clamping surface of the tension clamp is made of a material that is softer than the material forming the clamping area of the second section of the telescopic rod part.

5. The assembly method according to claim 1 , wherein the clamping area of the second section of the telescopic rod part is provided on a guide section of the piston located between a front and a rear piston seal, and that the clamping surface of the tool is made of a material that is softer than the material forming the guide section of the piston.

6. The assembly method according to claim 1 , wherein in the area of its clamping surface, the tool is provided with a softer material, preferably a sufficiently solid elastomeric material.

7. The assembly method according to claim 4 , wherein the guide section has a step and/or a groove and that, when the necessary frictional engagement is being established, the softer material acts as a compensating element for the surface contour of the guide section.

8. The assembly method according to claim 4 , wherein the tension clamp comprises two jaws, which are arranged such that they are pivotable relative to each other, that a distance (A S ) of the pivot axle from the axis of the telescopic rod part is smaller than the diameter (D F ) of the clamping area of the telescopic rod part and that, offset relative to the dividing plane of the jaws, a holding arm is arranged whose holder distance (A H ) from the axis of the telescopic rod part is larger than the diameter (D F ) of the clamping area of the telescopic rod part.

9. The assembly method according to claim 4 , wherein the tension clamp comprises a wire strap loop, which is adjustable with respect to its clamping circumference by means of an adjusting element, and that the wire strap loop is positioned on the clamping area of the second section of the telescopic rod part for establishing a sufficiently strong frictional engagement.

10. The use of a telescopic rod part of a length-adjustable connecting rod in a method according to claim 1 , wherein the telescopic rod part comprises a first section comprising a connecting-rod eye and having a connection thread, and a second section comprising the piston rod, to which a piston is fixedly connected, and having a connection thread.

Assignees

• Iwis Motorsysteme Gmbh & Co Kg
• Avl List Gmbh

Inventors

• Heller Malte
• Bezner Stefanie
• Lösch Siegfried
• Felgitscher Johann

Classifications

• F16C2226/10

  Force connections, e.g. clamping · CPC title

• B25B27/143

  for installing wire thread inserts or tubular threaded inserts · CPC title

• F16C2360/22

  Internal combustion engines · CPC title

• F16C7/06 Primary

  Adjustable connecting-rods · CPC title

• F02B75/045 Primary

  by means of a variable connecting rod length · CPC title