A Dissertation on the Construction of Locks: Containing, First - Reasons and Observations, Demonstrating All Locks, which Depend on Fixed Wards, to be Erroneous in Principle, and Defective in Point of Security. Secondly - a Specification of a Lock, Constructed on a New and Infallible Principle, Which, Possessing All the Properties Essential to Security, Will Prevent the Most Ruinous Consequences of House Robberies, and be a Certain Protection Against Thieves of All Descriptions |
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Expressions et termes fréquents
action admit againſt appear applied art of Lock-making Baron's barrel bear becomes block bolt bring cells common complete confidence conſtructed containing contrive courſe defective demonftrate depend deſcribed direct direct line edge effect effort equal exactly excellence expreffed extreme point face falſe key fame fecurity fhall fide figure fitted FIXED WARDS fliders fome force formed fprings frame fubject fuch fufficient furface give given greater groove hath height imperfection importance impreffion improvement infallible inftrument ingenuity interior invention lefs levers liable liberty likewiſe Lock machine means mechanical method moft moſt motion movement muſt notches obfervation objects obtaining opening operation oppofite paffage PATENT perfect perfectly plate poffefs poffible pofition practice prefent preffure prepared principle proceed produce projected proper key prove purpoſe receive rendered reprefents require robbery ſecurity ſpace tally thefe theſe thofe thoſe tion tumblers unequal uſe variations withdrawn workman
Fréquemment cités
Page 43 - ... by thofe keys, which as is well known, may be procured at the old iron (hops to fit almoft any lock in ufe. Such robberies are generally committed where the fervants are allowed to take the key with them, when fent on errands, it being impracticable while the key is fixed in the lock. The variations...
Page 31 - The inviolable reftraint upon this lock, by which means it is fubjected only to the action of the key, is lodged in the part E, which is a thin plate, bearing at each extremity on a block, and having of courfe a vacant fpace beneath, equal in height to the thicknefs of the blocks on which it refis.
Page 14 - ... which acts upon the tumbler as the tumbler acts upon the bolt: the application therefore of any force to the tumbler, which is fuperior to the force of the fpring, will caufe it to quit its hold, and fet the bolt at liberty.
Page 32 - ... unequal pressure upon the levers, be formed into a groove in a direct line with the edge of the plate E, which the notches are exactly fitted to receive. The least motion of the machine, while the levers are in this...
Page 18 - By giving (fays he) an uniform motion to the tumblers, and prefenting them with a face which exaitly tallies with the key, they ftill partake, in a very great degree, of the nature of fixed wards; and the fecurity of his lock is thereby rendered in a proportionable degree defective. Thus, fuppofe the falfe key to have pafled the wards, and to be in contact with the moft prominent of the tumblers, the impreffion, which the flighteft touch will leave on the key, will direct the application of the nie...
Page 42 - ... fufpended till the notches on the projections of the fliders are forced, by the preflure of the key, into a line with each other : a groove being thus formed on the fpherical furface of the barrel...
Page 27 - As nothing (says he) can be more opposite in principle to fixed wards than a lock which derives its properties from the motion of all its parts, I determined that the construction of such a lock should he the 'subject of my experiment.
Page 36 - The key must therefore be made first, and the inequalities upon the surface of the bit worked as chance or fancy may direct, without any reference to the lock. The key being thus completed and applied to the surface of the levers, will, by a gentle...
Page 43 - ... of the levers ; the other from the number of points contained on the projected furface of each lever ; by which the pofition of its notch may in the fmalleft degree be varied.
Page 7 - The principle on which all locks depend, is the application of a lever to an interior bolt, by means of a communication from without ; so that, by means of the latter, the lever acts upon the bolt, and moves it in such a manner as to secure the...
Informations bibliographiques
| Titre | A Dissertation on the Construction of Locks: Containing, First - Reasons and Observations, Demonstrating All Locks, which Depend on Fixed Wards, to be Erroneous in Principle, and Defective in Point of Security. Secondly - a Specification of a Lock, Constructed on a New and Infallible Principle ... Numéro 13077 de Goldsmiths'-Kress library of economic literature |
| Auteur | Joseph Bramah |
| Éditeur | author. Sold, 1785 |
| Original provenant de | Université d'Oxford |
| Numérisé | 1 déc. 2006 |
| Longueur | 46 pages |
| Exporter la citation | BiBTeX EndNote RefMan |