Pulling tool for extracting ring inserts

• US 5,787,561 A
• Filed: 06/07/1995
• Issued: 08/04/1998
• Est. Priority Date: 10/15/1993
• Status: Expired due to Fees

• Current Assignee: The Harmand Family Limited Partnership
• Original Assignee: Harmand Family Limited Partnership A California Limited Partnership
• Inventors: Harmand, Brice
• Primary Examiner(s): Watson, Robert C.
• Application Number:
  US08/475,638
• Time in Patent Office: 1,154 Days
• Field of Search: 29/262, 29/261, 29/265, 29/252, 29/254, 29/280, 29/283
• US Class Current: 29/255
• CPC Class Codes: B25B 27/06 inserting or withdrawing sleeves or bearing races
• CPC Class Codes: Y10T 29/53657 to apply or remove a resilient article [e.g., tube, sleeve, etc.]
• CPC Class Codes: Y10T 29/53843 Tube, sleeve, or ferrule inserting or removing

Abstract

The pulling tool has a pulling head for gripping an insert, such as an ene valve seat or a pre-combustion chamber, and for pulling it out of a recess. A gripping mechanism for an annular insert, such as a valve seat, may grip the insert by its inner edges. Such a gripping mechanism includes a shaft that slides freely through a bore in the body in a direction parallel to the body. At the end of the shaft is a cone, which cooperates with at least two toothed claws. The toothed claws may be pivotally mounted on a lower extension of the body or may be integrally formed with one another as a collet and flex radially outwardly. The body may have a lever that, when depressed, lifts the shaft, pulling up on the cone, causing the claws to move outward, and causing teeth to penetrate the metal of the insert on its inner diameter to lock into the insert. A gripping mechanism for an insert having a central or eccentric opening, such as a pre-combustion chamber, may have a pivoting claw arm with a tooth on one end. The end of the arm with the tooth is inserted into the opening of the insert at an oblique angle. A set screw forces the claw arm to pivot, which causes the tooth to penetrate the metal of the insert from behind. A pneumatic puller may be used with either gripping mechanism to remove the gripped insert from the recess.

Claims

1. A pulling tool for extracting an insert from a recessed area, said insert having an outside surface, an inside surface, a first diameter, and an opening between said outside and inside surfaces, said opening having a second diameter smaller than said first diameter, comprising:

a pulling head having an axis;

a shaft having a first end and a second end, said first end being attached to said pulling head so that said shaft is coaxial with said axis of said pulling head;

a single claw pivotally mounted on said pulling head for pivoting on an axis perpendicular to and off-axis with respect to said shaft, said claw having first and second elongated claw portions with a pivot pin therebetween;

said first elongated claw portion having a tooth for engaging said inside surface of said insert when said first elongated claw portion extends through said opening at an oblique angle with respect to said shaft, said pulling head contacting said outside surface when said first elongated claw portion extends through said opening at said oblique angle;

means for applying a gripping force to said second elongated claw portion for pivoting said first elongated claw portion toward said inside surface of said insert; and

means for applying a pulling force to said shaft for urging said pulling head in a direction away from said recessed area.

2. A pulling tool as in claim 1 wherein said means for applying a pulling force comprises:

a cylinder having an inner diameter, a first end and a second end;

a piston disposed within said cylinder;

means for introducing compressed air into said second end to drive said piston toward said first end so that it strikes an interior of said first end; and

means for releasing said compressed air from said cylinder after said piston has struck said interior of said first end so that said piston returns to said second end;

wherein said second end of said shaft is attached to said second end of said cylinder and the force created by said piston striking said interior of said first end is transferred to said shaft.

3. A pulling tool as in claim 1 wherein said first and second elongated claw portions are oriented at a nonzero angle with respect to one another.

4. A pulling tool as in claim 3 wherein said non-zero angle is approximately 125 degrees.

5. A pulling tool as in claim 3 wherein said means for applying gripping force to said second elongated claw portion comprises a set screw.

6. A pulling tool as in claim 5 wherein said second elongated claw portion is parallel to said shaft when said first elongated claw portion extends through said opening.

7. A pulling tool as in claim 6 wherein said means for applying a pulling force comprises:

a cylinder having an inner diameter, a first end and a second end;

a piston disposed within said cylinder;

means for introducing compressed air into said second end to drive said piston toward said first end so that it strikes an interior of said first end; and

means for releasing said compressed air from said cylinder after said piston has struck said interior of said first end so that said piston returns to said second end;

wherein said second end of said shaft is attached to said second end of said cylinder and the force created by said piston striking said interior of said first end is transferred to said shaft.

8. A pulling tool as in claim 1, wherein:

said claw has a notch for removably engaging said pivot pin; and

said pulling tool further comprises a spring-biased pin in contact with said second claw portion for biasing said notch into engagement with said pivot pin.

9. A pulling tool for extracting an insert from a recessed area in a housing, said insert having an outer sidewall, an inner dimension, and a top portion having an exterior surface and an interior surface, said top portion having an opening therethrough having a diameter less than said inner dimension, said pulling tool comprising:

a pulling head comprising;

a body having an upper portion and a lower portion, said lower portion having a claw attachment area disposed therein;

a pivot pin disposed within said claw attachment area;

a removable claw having a distal end and a proximal end, said removable claw being pivotably disposed on said pivot pin so that said distal end extends beyond said lower portion of said body, said distal end having a tooth extending therefrom;

means for applying a gripping force to said proximal end of said removable claw for pivoting said distal end of said removable claw and said tooth;

a shaft having a first end and a second end, the first end being attached to said upper portion of said body;

pulling force means in contact with said shaft for applying a pulling force to said shaft for urging said pulling head in a direction away from said recessed area;

wherein said pulling head is disposed in contact said exterior surface of said top portion with said distal portion of said removable claw extending through said opening at an angle, said means for applying a gripping force causes said tooth to engage said interior surface of said top portion, and the pulling force causes said distal end of said removable claw to pull against the interior surface of said top portion to pull said insert away from said recessed area.

10. A pulling tool as in claim 9 wherein the pulling force means comprises:

a cylinder having an inner diameter, a first end and a second end;

a piston disposed within said cylinder;

means for introducing compressed air into said second end to drive said piston toward said first end so that it strikes an interior of said first end; and

means for releasing said compressed air from said cylinder after said piston has struck said interior of said first end so that said piston returns to said second end;

wherein said second end of said shaft is attached to said second end of said cylinder and the force created by said piston striking said interior of said first end is transferred to said shaft.

11. A pulling tool as in claim 9 wherein said distal end and said proximal end of said removable claw are disposed at a non-zero angle with respect to each other.

12. A pulling tool as in claim 11 wherein said nonzero angle is approximately 125 degrees.

13. A pulling tool as in claim 9 wherein said means for applying a gripping force to said proximal end comprises a set screw rotatably disposed within said body so that a portion of said set screw is partially extendable into said claw attachment area.

14. A pulling tool as in claim 11 wherein said proximal end is substantially parallel to said shaft when said distal end is inserted through said opening.

15. A pulling tool as in claim 9, wherein said removable claw further includes a notch between said distal end and said proximal end for engaging said pivot pin.

16. A pulling tool as in claim 15, further comprising a spring-biased pin disposed within said body so that a portion of said spring-biased pin extends into said claw attachment area, said spring biased pin being adapted for applying a biasing pressure against said proximal portion of said removable claw for biasing said notch into engagement with said pivot pin.

17. A pulling tool for extracting a pre-combustion chamber from a diesel engine, the pre-combustion chamber having a generally cylindrical shape, a top portion and an opening through said top portion, said opening having an opening dimension smaller than an inner diameter of said generally cylindrical shape and being disposed eccentrically with respect to an axial center of said pre-combustion chamber, the pulling tool comprising:

a body having an upper portion and a lower portion, said lower portion having a recessed area therein;

a pivot pin disposed within said recessed area;

a pivoting claw having a distal portion, a pivot point, and a proximal portion disposed at an angle relative to said distal portion, said pivoting claw being pivotably mounted on said pivot pin at said pivot point so that said proximal portion is retained within said recessed area and said distal portion extends beyond said lower portion of said body;

an engaging tooth extending from said distal portion in a generally upward-facing direction;

pivoting force means disposed within said body and in contact with said proximal portion of said pivoting claw for applying a pivoting force to said proximal portion for pivoting said pivoting claw at said pivot point;

a shaft having a first end and a second end, the first end being attached to said upper portion of said body;

pulling force means in contact with said shaft for applying a pulling force to said shaft for urging said body in a direction away from said diesel engine;

wherein when said body is disposed in contact with an exterior surface of said top portion of said pre-combustion chamber and said distal portion of said pivoting claw is inserted through said opening substantially at said angle, said pivoting force means applies a pivoting force causing said distal portion of said pivoting claw to pivot toward an interior surface of said top portion so that said tooth engages said interior surface, and the pulling force causes said distal portion of said removable claw to pull against the interior surface of said top portion to pull said pre-combustion chamber away from said diesel engine.

18. A pulling tool as in claim 17 wherein said pivoting force means comprises a set screw rotatably disposed within said body so that a portion of said set screw is partially extendable into said recessed area.

19. A pulling tool as in claim 17 wherein said proximal portion of said pivoting claw is substantially parallel to said shaft when said distal portion is inserted through said opening.

20. A pulling tool as in claim 17, further comprising a spring-biased pin disposed within said body so that a portion of said spring-biased pin extends into said recessed area, said spring biased pin being adapted for applying a biasing pressure against said proximal portion of said pivoting claw for biasing said pivot point into engagement with said pivot pin.