Assisted opening mechanism for a folding knife

1. A folding knife comprising:

a pair of handle sides;

a blade having a sharpened working end and a tang end pivotally connected between the pair of handle sides for rotational movement between an open position where the blade is extended from the pair of handle sides and a closed position where the blade is interposed between the pair of handle sides; and

an assisted opening mechanism including an elongated bar spring mounted to one of the pair of handle sides and spaced parallel to the blade, and a contact pin extending from the tang of the blade configured to rotate with the blade movement from a first end position through a first intermediate range, a second intermediate range, a third intermediate range into a second end position such that the contact pin may rotate from the first end position through the first intermediate range without being biased by the elongated bar spring into engagement with the bar spring through the second intermediate range where the elongated bar spring engages the contact pin and biases the blade towards the first intermediate range, and the contact in may further rotate past an inflection point into the third intermediate range where the pin is biased towards the second end position, the contact pin forcibly engages the bar spring to hold the blade in the closed position and no other mechanism additionally holds the blade closed.

2. The folding knife of claim 1 wherein the one of the pair of handle sides includes a scale part having a recessed cavity defined therein and a liner part covering the recessed cavity.

3. The folding knife of claim 2 wherein the bar spring is disposed within the recessed cavity, the liner part having an arcuate slot defined therein in open communication with the cavity, the contact pin extending through the arcuate slot into the cavity.

4. The folding knife of claim 2 wherein the bar spring has a first end restrictively seated within a slot defined in the recessed cavity and a second end having an angled face.

5. The folding knife of claim 4 wherein the contact pin abuts the angled face when the blade is in the closed position.

6. A folding knife comprising:

a pair of handle sides, one of the pair of handle sides includes a scale part having a recessed cavity defined thereon and a liner part covering the recessed cavity, the liner part having an arcuate slot defined therin in open communication with the cavity;

a blade having a sharpened working end and a tang end pivotally connected between the pair of handle sides for rotational movement between an open position where the blade is extended from the pair of handle sides and a closed position where the blade is interposed between the pair of handle sides; and

an assisted opening mechanism including an elongated bar spring disposed within the recessed cavity and spaced parallel to the blade, and a contact pin extending from tang of the the blade through the arcuate slot into the cavity, such that the contact pin is configured to rotate with the blade movement from a first end position through a first intermediate range, a second intermediate range, a third intermediate range into a second end position; such that the contact in may rotate from the first end position through the first intermediate range without being biased by the elongated bar spring into engagement with the bar spring through the second intermediate range where the elongated bar spring engages the contact in and biases the blade towards the first intermediate range, and the contact in may further rotate past an inflection point into the third intermediate range where the pin is biased towards the second end position where the elongated bar spring forcibly engages the bar spring to hold the blade in the closed position; the bar spring having a first end restrictively seated within a slot defined in the recessed cavity and a second end having an angled face, the contact pin abuts the angled face when the blade is in the closed position and no other mechanism additionally holds the blade closed.

7. A method of using a folding knife comprising:

providing a folding knife having a pair of handle sides;

providing a blade having a sharpened working end and a tang end with a contact pin extending from said tang end; and

providing an assisted opening mechanism including an elongated bar spring having one end mounted fixedly between the pair of handle sides and an opposite end movable as a cantilever;

moving said blade from an operative open position to a closed position,

said moving said blade causes said contact pin to move from a from a first end position through a first intermediate range, a second intermediate range, a third intermediate range, and into a second end position;

the contact pin is rotated from the first end position through the first intermediate range without being biased by the elongated bar spring

the contact pin is then moved further to become engaged with the bar spring throughout the second intermediate range where the elongated bar spring engages the contact pin and biases the blade towards the first intermediate range; and

moving the contact pin further to rotate past an inflection point into the third intermediate range where the pin is biased towards the second end position where the elongated bar spring forcibly engages the bar spring to hold the blade in the closed position without an additional mechanism to assist in holding.