Button operated combination lock

• US 4,748,833 A
• Filed: 09/15/1981
• Issued: 06/07/1988
• Est. Priority Date: 10/21/1980
• Status: Expired due to Term

• Current Assignee: Nagasawa Manufacturing Co., Ltd.
• Original Assignee: 501 Nagasawa Manufacturing Company Limited
• Inventors: Nagasawa, Chiyokichi
• Primary Examiner(s): Gall, Lloyd A.
• Application Number:
  US06/302,606
• Time in Patent Office: 2,457 Days
• Field of Search: 70/298, 70/297, 70/207, 70/209, 70/214, 70/220, 70/224, 70/287, 70/288, 70/299, 70/129, 70/315, 70/133, 292/39, 292/142, 292/172
• US Class Current: 70/214
• CPC Class Codes: E05B 37/16 with two or more push or pull knobs, slides, or the like E05B65/461 takes precedence
• CPC Class Codes: Y10T 70/5788 Push pin or button
• CPC Class Codes: Y10T 70/722 Manually operable
• CPC Class Codes: Y10T 70/7322 Permutation

Abstract

This invention relates to a so-called "keyless" type button operated combination lock which can be unlocked by a button operation and locked by a handle operation. A number of buttons exposed on the front side of a case can be set in a combination and a key plate that engages with a bolt lock and keeps it in the locked state is unlocked by setting the buttons, and actuator keys to which they are attached, to a combination but prevents unlocking if the unlocking operation is erroneously carried out. These keys are made in the same shape and size, and the set positions for the memory state and the non-memory state can be interchanged by reversing key positions. These keys are loosely inserted into corresponding slits in the key plate and permit the selection of various operating conditions in conjunction with the key plate slits. When the keys are brought into the "ON" state, they are detachably hooked to the lock plate. The handle, which is operative in the interlocking arrangement with the bolt lock, permits the key plate and the lock plate to simultaneously operate under engagement with each other via a cam pin. Another cam pin engages only with the above-mentioned cam pin and with the lock plate. These cam pins are interchangeable with each other so that the lock of the invention can be fitted to the door as a right-handed type or a left-handed type.

Claims

1. In a button operated combination lock of the type in which a number of button operable actuator keys are disposed with the surfaces thereof accessible in a case frame so as to be capable of being set in a selected combination lock memory state and engaging with, and disengaging from, a key plate, said key plate being engaged with a bolt lock;

the improvement wherein said key plate is slidably supported inside said case frame and has a number of slits bored at predetermined positions therein;

all of said actuator keys being in the form of similar flat plates, each of said said keys being loosely inserted into a corresponding one of said slits and being retractable from said case frame;

a transverse slot formed in each of siad keys intersecting and engaging with said key plate loosely, each of said slots running parallel to and being displaced longitudinallly from the transverse centerline of its associated key, said keys being set in said selected memory state by mounting a preselected set of said keys in said lock with the slots thereof displaced from the transverse centerline in a first direction relative to said key plate with the remainder of said keys being mounted in said lock in inverse relationship to the preselected keys with the slots thereof displaced from said transverse centerline in a direction opposite to said first direction, the slots thereof engaging the key slits when the keys are actuated;

a lock plate slidably mounted in said case frame;

said lock plate and said actuator keys each including means for detachably retaining said actuator keys to said lock plate; and

handle means operative in an interlocking arrangement with said bolt lock and engaging with said key plate and with said lock plate for alternatively opening said lock or resetting said keys in the selected combination memory state by detaching said actuator keys from said lock plate.

2. The button operated combination lock as defined in claim 1 wherein said keys have an outer shape so as to be capable of being inverted and said slots are so formed as to enable selection of a memory position and an non-memory position, said keys being linearly symmetric when said keys are inverted.

3. The button operated combination lock as defined in claim 1 wherein said means for detachably retaining the actuator keys to the lock plate comprises notches formed at both end portions of said keys and hook springs disposed on said lock plate capable of hooking to said notches.

4. The button operated combination lock as defined in claim 1 wherein a set block having said key plate and said keys set thereto is screwed detachably to said case frame form the back of said case frame.

5. The button operated combination lock as defined in claim 1 wherein said handle includes a cam pin on one side thereof engaging with said lock plate and a cam pin on the other side thereof engaging with said lock plate.

6. The button operated combination lock as defined in claim 5 wherein said handle further includes a rack gear and a pinion, said rack gear having both of said cam pins thereon, said rack gear engaging said pinion.