1. Field of Invention
The invention relates to a method of locking a positioning mechanism, more particularly, a method of locking a rotating, tilting and positioning vise with cam profile shaped locks.
2. Description of Prior Art
The traditional hand engraving vise which has been in existence since the nineteenth century, consists of a ball base resting in a doughnut type cradle. The top half of the ball is made to pivot on a center axis. On top of this are the vise jaws. When the engraver, jeweler or craftsman desires to hand engrave an arc on an object that is clamped in the jaws, he simply turns the vise with one hand, while the other hand holds the engraving point on the surface of the object that is being engraved. The location of the rotating object being engraved has a direct affect on the degree of difficulty in engraving an arc. The location of the rotating pivot position depends on where the object is clamped in the jaws of the vise. An arc is easiest to engrave when it has its center location closest to the center pivot position of the rotating vise. Engravers and jewelers therefore become accustomed to unclamping, moving and reclamping the object in the vise jaws many times in the course of a project. Unfortunately, clamping and unclamping to position the object in reference to the vise pivoting location can become a problem since the objects engravers and jewelers work on are often delicate and can be damaged if clamped incorrectly. In addition, a lot of time is used unclamping and clamping. Another example of the need to position a working area of an object in the center of a rotating vise is when delicate hand working operations are executed with a microscope. The microscope is centered over the rotating pivot position of the vise. The field of view through the microscope is limited and in order to keep a particular spot in view, the axis of rotation needs to stay in the center of the field of view of the scope, otherwise the area being viewed will swing out of view when the vise is rotated.
Tilting prior art engraving vises utilized a partial sphere for the bottom half of the rotating assembly set in a cradle base made of materials such as rubber and leather. The weight of the vise and the material the cradle is made of determines how much grip is on the sphere to prevent the vise from titling unexpectedly. This method of holding the tilting vise can be unpredictable and the entire vise assembly has been known to fall and tilt unexpectedly.
Disclosed in publication titled GRS POSITIONING VISE by GRS Corporation as well as photographs by applicant of a disassembled GRS Corporation positioning vise is a rotating positioning vise. The vise jaw apparatus on top of this prior art vise is made to slide around for positioning and then lock. The locking mechanism utilizes one spring in earlier models for holding the lock state. Later models used two springs. The one or two springs are connected to a lever. This lever has detent holes in it. There are two steel ball bearings fixed in position in the block that are spaced the same distance as the detent holes in the lever. When the positioning is locked, the holes in the lever do not line up with the holes. In this state the lever is pushing against a friction plate to lock the positioning of the vise. To unlock a user moves the spring loaded lever and the detent holes in the lever then align with the two ball bearings in block. This allows the lever to be lowered and thus loosens the pressure on the friction plate that allows the user to position the vise. The lever requires two hands to overcome the resistance of the springs to unlock. Additionally there is a wear point on a “lock button” described in the GRS Corporation publication. When it is worn, the mechanism will not lock well and requires repair shims. As is true to other prior art, this vise does not have a lock mechanism to lock the tilt.
In short, an improved positioning vise should have a unique and simple method to lock the positioning as well as the tilting movements. The locking mechanisms should be easily and quickly locked and unlocked at will by the user without a lot of resistance effort or needing to use both hands to lock and unlock. The locks should take up any wear themselves and not require repair shims.
It is the object of this invention to provide lever operated cam locking mechanisms for an engraver's, jeweler's or craftsman vise, however the nature of the invention could be utilized for other applications. The small lock handles on this vise application can be operated with one hand. The mechanical advantage is that eccentric cams allow a lot of mechanical advantage and holding power without a lot of resistance for a user to lock and unlock the mechanisms.
The preferred embodiment of the invention is described below with reference to attached drawing figures, wherein:
A rotating, positioning and tilting vise with cam locks in accordance with the present invention is illustrated in
Operation
Referring to
Referring to
Referring to
Note: Cam-shape-profile 32 and cam-shape-profile 54 have been drawn as an eccentric shaped cam, meaning that their profile is round or circular and off center from the round rod they are made on. A cross section of cam-shape-profile 54 is illustrated in
Accordingly, the reader will see that the invention provides a rotating, positioning and tilting vise that allows ease of freedom of movement for a jeweler, engraver or craftsman. The locking method is unique and yet a simple method to lock the positioning as well as tilting movements. The locking mechanisms are easily and quickly locked and unlocked at will by the user without a lot of resistance effort or needing to use both hands to lock and unlock. The mechanical advantage of eccentric cams allows a lot of holding power without a lot of resistance for a user to lock and unlock the mechanisms. Although the invention has been described with reference to the illustrated embodiment, it is noted that equivalents may be employed and substitutions made herein without departing from the scope of the invention as recited in the claims. For example: Eyebolt 52, u-joint-ball 50 and u-joint-socket 48 could be replaced with different linkages that would give the equivalent effect. For instance a cable or wire could be used here. The locking tilt and the top positioning lock could be used by themselves in an apparatus. Base-plate 2 and cradle 4 could be combined and made from one piece without departing from the scope of the invention. Although the device was made for jewelers, engravers, and craftsman, the invention can be used by other trades that would benefit from a locking tilting apparatus or a locking positioning apparatus.
Accordingly, the scope of the invention should be determined not by the embodiment illustrated, but by the appended claims and their legal equivalents.
Number | Name | Date | Kind |
---|---|---|---|
86173 | Dickenson | Jan 1869 | A |
132127 | Wilcox | Oct 1872 | A |
269708 | Thompson | Dec 1882 | A |
274242 | Plummer | Mar 1883 | A |
340429 | Maynard | Apr 1886 | A |
420968 | Seaman | Feb 1890 | A |
420969 | Seaman | Feb 1890 | A |
420970 | Seaman | Feb 1890 | A |
481238 | Muehlmatt | Aug 1892 | A |
565425 | Donlevy et al. | Aug 1896 | A |
790540 | Valentine | May 1905 | A |
829771 | Francis | Aug 1906 | A |
911667 | Muehlmatt | Feb 1909 | A |
983091 | Skow et al. | Jan 1911 | A |
1333432 | Maller | Mar 1920 | A |
1397293 | Plummer | Nov 1921 | A |
1555774 | Thompson | Sep 1925 | A |
1665819 | Plummer | Apr 1928 | A |
1697117 | Hilstad et al. | Jan 1929 | A |
1936968 | Neal | Nov 1933 | A |
1981253 | Schulz | Nov 1934 | A |
2070025 | Phillips | Feb 1937 | A |
2260995 | Kruczek | Oct 1941 | A |
2310025 | Giern et al. | Feb 1943 | A |
2371435 | Galorneau | Mar 1945 | A |
3815892 | Tulk | Jun 1974 | A |
4066231 | Bahner et al. | Jan 1978 | A |
4086704 | Masaichi | May 1978 | A |
4243212 | Bunyea et al. | Jan 1981 | A |
4306709 | Hurn | Dec 1981 | A |
4352489 | Wagster | Oct 1982 | A |
4702465 | McConnell | Oct 1987 | A |
4744552 | Glaser | May 1988 | A |
5224692 | Anderson et al. | Jul 1993 | A |
6071031 | Bailey | Jun 2000 | A |
6698738 | Wiebe | Mar 2004 | B2 |
6978989 | Glaser et al. | Dec 2005 | B2 |
7097170 | Glaser et al. | Aug 2006 | B2 |