I claim the ornamental design for a turnbuckle lock, as shown and described.
FIG. 1 is a top, front, right side perspective view of a turnbuckle lock showing my new design;
FIG. 2 is a right side elevation view thereof;
FIG. 3 is a left side elevation view thereof;
FIG. 4 is a top plan view thereof;
FIG. 5 is a bottom plan view thereof;
FIG. 6 is a front elevation view thereof;
FIG. 7 is a rear elevation view thereof;
FIG. 8 shows the turnbuckle lock attached to a turnbuckle, wherein a pivotable arm is in a locked position; and,
FIG. 9 shows the turnbuckle lock attached to a turnbuckle, wherein the pivotable arm is in an unlocked position.
The broken away symbols in the drawings indicate that any portion of the article beyond what is shown forms no part of the claimed design. The broken lines shown in FIGS. 8 and 9 illustrating a turnbuckle are for the purpose of illustrating environment and form no part of the claimed design.