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(11) | EP 1 475 189 A1 |
| (12) | EUROPEAN PATENT APPLICATION |
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| (54) | Movable head for vises |
| (57) The pressure element (3), which can move with respect to the body (1) of the head
through the effect of the typical manual lever (5), approaching or moving away from
the complementary fixed head, is driven by said lever (5) through a bushing (10) with
a smooth outer surface, related to the body (1) through a pin (11), and to whose free
end the pressure element (3) is solidly joined; to this effect, the orifice in which
said bushing moves has a smooth section (6), while the bushing (10) is threaded internally,
receiving a section, also threaded (9) of a shaft that has another opposingly threaded
section (8), and which in turn combines with a threaded section (7) of the aforementioned
orifice on the body (1) of the head, all in such a way that the speed at which the
pressure element (3) moves forward or backward is doubled for one turn speed of the
manual lever (5); in addition, the distance between the lever (5) and the pressure
element (3) is considerably shorter for the same distance traveled by the latter,
and the threads of the vise are protected from the surrounding environment. |
OBJECT OF THE INVENTION
[0001] This invention refers to a movable head, which in combination with a fixed head and a guide, makes up a vise or handscrew able to clamp one object to another.
[0002] The object of the invention is to enable the pressure element of said head to advance quickly by means of a double thread, and also for said thread to be hidden within the head and suitably protected from the environment surrounding it.
BACKGROUND OF THE INVENTION
[0003] It is a known fact that, in the basic structure of a vise, handscrew or clamping screw, there is a fixed head that is integrated into one of the ends of a guide with a constant profile, on which a movable head travels on a slide. This head, together with the aforementioned fixed head, makes up the clamp gripping the object or objects in question.
[0004] The fact that the movable head can travel on the guide enables the clamping element to quickly approach the fixed head; however, definitive clamping takes place in a secondary maneuver in which the pressure element of the movable head moves, in turn, with respect to said head. To this effect, the latter has a threaded orifice, parallel to the guide, in which a screw moves. This screw finishes on one end with the aforementioned pressure element, while a driving element to supply the necessary turning motion to the screw is fastened to the end opposite the fixed head.
[0005] A vise of this type is shown, for example, in the Spanish utility model with application number U9900362, or in the utility model with application number U200202066.
[0006] This structure, which is essentially common to the vast majority of conventional vises of this type, presents a problem that primarily revolves around the following aspects:
- The traveling movement of the pressure element, to definitively close the vise on the items to be secured, is relatively slow because of the number of turns that must be applied to the screw in order to make the latter advance. If a broad scope of action is desired for this pressure element, the screw must also be of a considerable length, which has a negative impact on the vise's size.
- The aforementioned screw is usually in the open, so its thread is constantly exposed to external agents. While it is easy to lubricate, it is very difficult to maintain this lubrication over time, as the lubricant is just as easily lost. There is also a risk that dirt may adhere to the lubricant and be carried into the movable head's threaded orifice, possibly damaging the thread of said orifice or the thread of the screw itself.
DESCRIPTION OF THE INVENTION
[0007] The movable head that the invention proposes has been designed and structured in order to resolve the problems stated in the different areas discussed in a fully satisfactory manner.
[0008] More specifically, and starting with the basic structure of a conventional vice or clamping screw, which was previously mentioned, the object of the invention focuses on the fact that its movable head, instead of incorporating a threaded orifice, has a partially threaded orifice, obviously also parallel to the orifice for sliding on the guide, while the pressure element is mounted on a sliding bushing instead of on a conventional screw. This bushing, on the orifice's non-threaded section, is threaded internally and coaxially joined to a shaft, on which two sections with opposing threads are defined, i.e., one right-threaded and another left-threaded, so that one of them has a thread that is complementary to the one in the aforementioned bushing, while the other has, in turn, a thread that is complementary to the one in the threaded section of the head's orifice.
[0009] Thus, the turning motion given to the aforementioned shaft through its free end has a dual effect: on the one hand, the axial movement of the shaft itself on the threaded section of the head; and on the other hand, the movement, also axial and in the same direction, of the bushing with respect to said shaft, i.e., of the pressure element. Thus, the travel speed of said pressure element with respect to the body of the head will be double for one screw thread and for the same number of turns applied to the element driving the shaft, such as, for example, the typical diametric lever.
[0010] Obviously, in order for the vise or clamp to work in the way that has been described, said bushing must not be able to turn. To this effect, it will be duly secured to the body of the head with a pin.
[0011] In a complementary manner, the thread joining the shaft and bushing is permanently isolated from the outside, within a chamber, accessible through a lubricator.
[0012] The same effects are achieved by replacing the aforementioned bushing with a solid arm, extending into a threaded rod with a smaller diameter, which moves inside a bushing which, in turn, replaces the aforementioned shaft and which, in this case, has the two opposing threads. One is in its hollow interior, and the other on its outside; the latter relates to the threaded section in correspondence with the orifice on the body of the head.
DESCRIPTION OF THE DRAWINGS
[0013] To complement this description and for the purpose of allowing for better understanding of the characteristics of the invention, in accordance with an example of its preferred embodiment, a set of drawings of an illustrative and non-restrictive nature, in which the following items are represented, is attached as an integral part of this description:
Figure 1. Shows, according to a schematic representation in side elevation and cross-section view, a movable head for vices embodied in accordance with the object of this invention, which is shown with the pressure element in its position of maximum retraction.
Figure 2. Shows a representation similar to the previous figure, of the same assembly in said figure, now with the pressure element in maximum driving position, in other words, in the position of maximum approach to the fixed head of the vise.
Figures 3 and 4. Show representations similar to those in figures 1 and 2, but corresponding to a variation in the embodiment of the device.
PREFERRED EMBODIMENT OF THE INVENTION
[0014] The figures described show how the body of the head (1) incorporates a transverse orifice (2) in correspondence with one of its ends. This orifice serves to allow said body or movable head (1) to move along a guide not shown in the drawings, whose cross section coincides in shape and dimensions with that of the orifice (2). The head (1) is locked onto this guide because of the head's tendency to tilt laterally when its pressure element (3) is acted on, locking that may be favored by the existence of a brake (4) on the head (1), next to the orifice (2). The brake (4) is equipped with a toothed front that acts on the edge of the guide. In any case, the pressure element (3) can move parallel to said guide when a manual lever (5) is acted on, all in a conventional manner.
[0015] In accordance with the invention, and as can especially be seen in figures 1 and 2, at the end of the body (1) of the head, opposite the orifice (2), there is a second orifice parallel to the first one, formed by two coaxial sections. One section (6), the one closest to the pressure element (3), has a smooth surface, and the other (7) has an inner thread on which a shaft moves. The shaft, in turn, has two sections: a section (8) opposing the pressure element (3), which screws onto the aforementioned section (7) of the orifice on the body (1), and a second section (9), whose diameter is considerably smaller and whose thread direction is the opposite of the one on section (8), which in turn screws into a bushing (10). This bushing has a threaded inner surface in correspondence with section (9), and its outer surface slides on the unthreaded section (6) of the aforementioned orifice, while its free end receives the aforementioned pressure element (3) by means of a rivet or any other means. Said bushing (10) can only move axially in its housing as it is related to the body (1) of the movable head with the collaboration of a pin or similar device (11).
[0016] This allows maximum travel for the pressure element (3), with a minimal length for the combination of the bushing (10) and the shaft (8-9), with minimal effort applied to the manual lever (5).
[0017] On the other hand, the establishment of a lubricator (12) on the body (1) of the movable head is planned. This lubricator, as can especially be seen in figure 2, allows the chamber (13) defined between the shaft and bushing to be suitably lubricated, maintaining these elements in optimum operating conditions.
[0018] The alternative shown in figures 3 and 4 has also been foreseen, with practically the same performance characteristics. In this version, the structural characteristics of the body (1) of the movable head are fully maintained, especially with regard to the existence of the smooth and threaded sections (6) and (7) of its orifice for housing the means by which the pressure element (3) moves; however, in this case, these driving elements consist of a shaft (14) with a tubular structure, in other words, in the shape of a bushing with an inner thread (15) and an outer thread (16), whose direction is the opposite of the former's, so that while the latter relates said shaft to the threaded section (7) of the orifice on the body (1) of the head, its inner thread (15) receives the threaded end (17) of a rod, whose free section (18) moves in the smooth section (6) of the orifice on the head (1), already mentioned on several occasions, and also receives the pressure element (3) by means of a rivet (19) or any other means.
[0019] As previously stated, this solution offers the same functional performance as those represented in figures 1 and 2, and keeps all of the threads permanently hidden. In this case, the lubricator (12) is also maintained, to supply lubricant to the chamber (13') that is formed between the tubular shaft (14), the threaded arm (18) and the orifice on the body (1) of the head in which these elements move.
1. Movable head for vises, of the type that incorporates an elongated body (1) on one
of whose ends there is a transverse orifice (2) for the movement of said body (1)
along a guide, as it travels to quickly approach the fixed head in which said guide
ends, and on whose other end there is a second orifice parallel to the first one,
in which a means of travel parallel to said guide moves for a pressure element (3),
by acting on them with the collaboration of a manual lever (5); this movable head
for vises is characterized in that the aforementioned orifice on the end of the body (1) opposing the guide incorporates
two sections (6) and (7), one smooth and the other threaded, so that an element (10-18)
slides on the smooth section (6); the pressure element (3) is solidly joined to the
outer end of this element (10-18), which is related to a shaft (8-14) by means of
a thread; this shaft (8-14) has two opposing threads, so that it relates to said element
through one of them, while it relates to the threaded section (7) of the orifice on
the body (1) of the head with the other one; this shaft (8-14) receives the mechanism's
manual lever (5) diametrically through its free end.
2. Movable head for vises, according to the first claim, characterized in that the shaft (8) incorporates two coaxial sections with different diameters: section
(8) with a larger diameter, through which it relates to the threaded section (7) of
the orifice on the body (1) of the head, and a second section (9) with a considerably
smaller diameter, threaded in the opposite direction from the former, which moves
in the hollow interior of the element (10) supporting pressure element (3); said element
(10) is made up of a bushing with a smooth outer surface and a threaded inner surface.
3. Movable head for vises, according to the first claim, characterized in that the shaft (14) is made up of a bushing with an outer thread (16), which is complementary
to the threaded section (7) of the orifice on the body (1) of the head, and with an
inner thread (15) through which it receives the threaded end (17) of the element (18)
to which the pressure element (3) is solidly joined; this element (18) is made up
of an arm with a smooth outer surface that moves in the also smooth section (6) of
the hole on the body (1) of the head and which extends axially into the aforementioned
threaded section (17).
4. Movable head for vises, according to previous claims, characterized in that the sliding element (10-18) to which the pressure element (3) is solidly joined is
related to the smooth section (6) of the orifice on the body (1) of the head through
a pin (11) which prevents it from turning while allowing longitudinal movement.
5. Movable head for vises, according to previous claims, characterized in that on the wall of the orifice (6-7) on the body (1) of the head there is a lubricator
(12) providing access to the chamber (13-13') defined within said orifice by the element
(10), (18) and by the shaft (8-9), (14).