Cylinder-and-piston arrangement and method of manufacturing the same

• US 4,096,787 A
• Filed: 10/08/1976
• Issued: 06/27/1978
• Est. Priority Date: 12/05/1975
• Status: Expired due to Term

• Current Assignee: Robert Bosch GmbH
• Original Assignee: Robert Bosch GmbH
• Inventors: Ritter, Klaus, Sandau, Hartmut, Kochendorfer, Heinrich, Kraisel, August, Steinel, Winfried, Gaub, Erwin, Weigert, Wilhelm
• Primary Examiner(s): Cohen, Irwin C.
• Application Number:
  US05/730,713
• Time in Patent Office: 627 Days
• Field of Search: 92/231, 92/260, 403/271, 403/272, 403/157, 29/156.5 A, 228/112
• US Class Current: 92/260
• CPC Class Codes: B23K 20/129 specially adapted for particular articles or workpieces
• CPC Class Codes: B23P 15/00 Making specific metal objects by operations not covered by a single other subclass or a group in this subclass
• CPC Class Codes: Y10T 29/49256 with assembly or composite article making
• CPC Class Codes: Y10T 403/32918 fork and tongue

Abstract

A piston rod connected at one end to a piston slidably arranged in a cylinder projects with its other end through an opening in an end wall of the cylinder beyond the latter and a fork-shaped member is connected by a friction weld, that is without adding welding material or external heat, to the other end of the piston rod.

Claims

1. A method of forming a fork-shaped member and of connecting the same to one end of a piston rod projecting outwardly of a cylinder and connected at the other end with a piston, comprising the steps of bending without twisting a flat steel strip into a fork-shaped member having a base portion and a pair of parallel leg portions projecting parallel to each other and substantially normal to the base portion from opposite ends of the latter to one side thereof;

forming in said base portion midway between said opposite ends a substantially circular depression extending from the other side of the base portion into the latter and having a planar end face;

abutting said one end of said piston rod against said planar end face; and

friction welding said one end of said piston rod to said end face to fixedly connect said fork-shaped member to said piston rod.

2. A method as defined in claim 1, wherein said depression is formed by material deforming technique.

3. A method as defined in claim 2, wherein forming said depression is carried out subsequently to the bending of said flat steel strip.

4. A method as defined in claim 2, wherein forming of said depression is carried out simultaneously with the bending of said flat steel strip while the latter is in cold condition.

5. An arrangement of the character described comprising a cylinder;

a piston in said cylinder having a piston rod projecting with one end thereof beyond one end of said cylinder;

a fork-shaped member having a curved bottom portion against which said one end of said piston rod abuts, said fork-shaped member being constituted by a flat steel strip bent without twisting into U-shaped configuration; and

a friction weld connecting said one end of said piston rod with said bottom portion of said fork-shaped member.

6. An arrangement as defined in claim 5, wherein said flat steel strip is of rectangular outline having substantially parallel side faces.

7. An arrangement as defined in claim 5, wherein said curved bottom portion of said fork-shaped member is formed at the side thereof facing the cylinder with a central depression having a planar circular end face forming a welding face against which said one end of said piston rod abuts.

8. An arrangement as defined in claim 7, wherein said planar circular end face is at least along part of its circumference surrounded by a rim having an inner conical surface.

9. An arrangement as defined in claim 5, wherein the diameter of said circular end face is at least equal to the diameter of said one end of said piston rod.

10. An arrangement as defined in claim 5, wherein said fork-shaped member has a pair of substantially parallel legs defining a free space therebetween and wherein the diameter at said one end of said piston rod is larger than the width of said free space.

11. An arrangement as defined in claim 5, wherein said one end of said piston rod has a planar end face forming a welding face in engagement with said bottom portion of said fork-shaped member.