text: 1. Field of the Invention
  The present invention concerns a lock having a bolting means for bolting a latch bolt.
  2. Description of the Background Art
  More precisely, this invention concerns a lock installable in, e.g., a door leaf. The lock includes a case and a latch bolt movable within the case between a locking position, in which the latch bolt at least partly projects from the case, and an unlocking position, in which the latch bolt is retracted within the case. Generally, a lock of this kind includes some kind of bolting means adapted to bolt the latch bolt in at least its locked position. Such bolting means is generally factory mounted on one side of the case for access from a corresponding side of a door. Consequently, to comply with possible customer needs, it is necessary to manufacture two locks having the bolting means on opposite sides of the case.
  U.S. Pat. No. 5,779,287 discloses a lock having an optional bolting means, i.e., a bolting means that is separately delivered with the lock and that may be mounted in the lock by the user at need. This prior art lock includes a lock case having opposed walls and a latch bolt slidable between a locking position and an unlocking position. Each of the opposed walls is provided with an aperture for optionally receiving a holding bolt. The holding bolt is positionable in each aperture in a first, relatively retracted position allowing sliding of the latch bolt from its locking position to its unlocking position, and in a second relatively inserted position preventing sliding of the holding bolt from its locking position to its unlocking position. The optional bolting means further includes a spring for yieldably retaining the holding bolt in its first and second positions. The apertures are shaped such that once the holding bolt has been introduced in a selected aperture, it is automatically kept there by the spring pressing it towards a portion of the aperture preventing its withdrawal. However, withdrawal of the holding bolt is possible upon manually rotating it through a small, limited angle against the action of the spring. Since the free end of the holding bolt of this prior art lock needs to be axially and radially guided, the lock requires a relatively thick door leaf and particularly an escutcheon mounted onto the door leaf to guide the holding bolt and also to prevent its rotation and unintentional removal.