Pipe clamp with a headed bolt for securing a pipe connection

• US 5,944,365 A
• Filed: 09/25/1997
• Issued: 08/31/1999
• Est. Priority Date: 09/25/1996
• Status: Expired due to Fees

• Current Assignee: DaimlerChrysler AG (Mercedes-Benz Group AG)
• Original Assignee: Daimler-Benz AG (Mercedes-Benz Group AG)
• Inventors: Tiefenbacher, Gerd, Kizler, Wolfgang
• Primary Examiner(s): Reichard, Lynne
• Assistant Examiner(s): BINDA, GREGORY JOHN
• Application Number:
  US08/936,747
• Time in Patent Office: 705 Days
• Field of Search: 29/890.08, 285/187, 285/329, 285/373, 285/419, 285/420, 285/422, 285/905, 285/380, 24/19, 24/279, 24/280, D 8/396, D 8/397, 411/399, 411/401, 411/380, 411/381, 411/382, 411/392
• US Class Current: 285/420
• CPC Class Codes: F16L 21/06 with a divided sleeve or ring clamping around the pipe-ends flanged joints F16L23/00; couplings of the quick-acting type F16L37/00
• CPC Class Codes: Y10S 285/905 Different coefficients of expansion
• CPC Class Codes: Y10T 29/49398 Muffler, manifold or exhaust pipe making

Abstract

A pipe clamp with a headed bolt for securing a pipe connection, in particular pipes of the exhaust system of a motor vehicle which are to be connected to one another, in the case of which the end of a first pipe is pushed into an axially slit end of a second pipe and, when the headed bolt is tightened, the pipe clamp, fitted on the slit pipe end, connects the two pipe ends to one another in a frictionally locking manner, is to be secured against a reduction in clamping force. For this purpose, the pipe clamp is formed of a material which has a higher coefficient of expansion than does the material of the pipes which are to be connected. The head of the headed bolt is elongated, in order to avoid impermissibly high local stressing during tightening of the pipe clamp. Due to the elongate form of the head of a headed bolt, the forces on the pipe clamp which support the tightening torque are reduced by a lengthening of the lever arm with respect to the axis of the headed bolt.

Claims

1. A pipe connection comprising:

pipes of an exhaust system of a motor vehicle which are to be connected together,

a headed bolt and a nut for securing said pipes of said exhaust system of the motor vehicle to one another by fitting an end of a first of said pipes into an axially slit end of a second of said pipes,

a pipe clamp which is to be fitted over the axially slit end and tightened by said headed bolt and the nut to connect the two pine ends to one another in a frictionally locking manner, said pipe clamp defining lugs at opposite ends thereof through which said bolt extends,

a clamping piece which is to be located between the lugs, and

a shaped piece which is to be disposed between one of the lugs and said nut,

wherein said headed bolt has a head in the form of a hammer head, said hammer head defining at least one recess on a side facing away from a shank of the bolt.

2. A pipe clamp according to claim 1, wherein, at least in a central region of the headed bolt, a base of the recess in the hammer head is spaced from the end of the shank of the headed bolt by at least half the value of the diameter of the shank.

3. A pipe connection comprising:

pipes of an exhaust system of a motor vehicle which are to be connected together,

a headed bolt and a nut for securing said pipes of said exhaust system of the motor vehicle to one another by fitting an end of a first of said pipes into an axially slit end of a second of said pipes,

a pipe clamp which is to be fitted over the axially slit end and tightened by said headed bolt and the nut to connect the two pipe ends to one another in a frictionally locking manner, said pipe clamp defining lugs at opposite ends thereof through which said bolt extends,

a clamping piece which is to be located between the lugs, and

a shaped piece which is to be disposed between one of the lugs and said nut,

wherein said headed bolt has a head in the form of a hammer head, said hammer head having two opposite transverse sides, a longitudinal extent of the transverse sides being asymmetrical with respect to an axis of the hammer head.

4. A pipe clamp according to claim 3, wherein, on the two opposite transverse sides of the hammer head, the longitudinal extent is largest at opposite ends, as seen in the longitudinal direction on either side of the axis of the hammer head.

5. A pipe connection comprising:

pipes of an exhaust system of a motor vehicle which are to be connected together,

a headed bolt and a nut for securing said pipes of said exhaust system of the motor vehicle to one another by fitting an end of a first of said pipes into an axially slit end of a second of said pipes,

a pine clamp which is to be fitted over the axially slit end and tightened by said headed bolt and the nut to connect the two pipe ends to one another in a frictionally locking manner, said pipe clamp defining lugs at opposite ends thereof through which said bolt extends,

a clamping piece which is to be located between the lugs, and

a shaped piece which is to be disposed between one of the lugs and said nut,

wherein the headed bolt has a head which is configured to be larger in an axial direction of the pipe clamp than in a direction perpendicular thereto, and

wherein a length of the head in the axial direction is two to three times the diameter of a shank of the bolt.

6. A pipe connection in an exhaust system of a motor vehicle, comprising:

a first exhaust pipe;

a second exhaust pipe having an axially slit end to be fitted over an end of said first exhaust pipe;

a pipe clamp to be fitted over said axially slit end of the second exhaust pipe, said pipe clamp being adjustable via a bolt and a nut which is rotatable to adjust an inner periphery of said pipe clamp to frictionally engage said axially split end of the second exhaust pipe and to bias said axially split end of the second exhaust pipe into frictional engagement with said first exhaust pipe, said pipe clamp defining lugs at opposite ends thereof through which said bolt extends;

a clamping piece which is to be located between the lugs; and

a shaped piece which is to be disposed between one of the lugs and said nut,

wherein said bolt includes a head and a shank defining an axial direction of said bolt, said head including a surface which engages a mating surface of said pipe clamp, said head being resilient relative to said shank in said axial direction.

7. A method of forming a pipe connection in an exhaust system of a motor vehicle, said method comprising the steps of:

selecting a first exhaust pipe;

selecting a second exhaust pipe with an axially split end;

selecting a pipe clamp, said pipe clamp being adjustable via a bolt and a nut;

fitting said axially slit end of said second exhaust pipe over an end of said first exhaust pipe;

fitting said pipe clamp over said axially slit end of the second exhaust pipe;

fitting a clamping piece between lugs defined at opposite ends of said pipe clamp;

fitting a shaped piece between one of the lugs and said nut; and

rotating said nut to adjust an inner periphery of said pipe clamp to frictionally engage said axially split end of the second exhaust pipe and to bias said axially split end of the second exhaust pipe into frictional engagement with said first exhaust pipe;

wherein said bolt includes a head and a shank defining an axial direction of said bolt, said head including a surface which engages a mating surface of said pipe clamp, said head being resilient relative to said shank in said axial direction.