The present invention relates to a device and method for holding a workpiece and, in particular, relates to an adjustable vise.
Irregularly shaped parts are frequently encountered in cast and forged components which require finishing operations. These irregularly shaped parts present significant challenges when being held with a typical vise, as shown in
The present invention provides a vise for holding irregularly-shaped parts with maximum functionality and minimum complexity. Referred to as the Positive Interlock Network vise, or PIN vise, it may be characterized by the following three aspects: Positive, Interlock and Network
The Positive aspect is characterized by the existence or presence of features, rather than by their absence. The positive aspect of the PIN vise of the present invention is that it fits around or even within the part to create a custom contour based on the features of the object being held.
Interlock means that two or more things engage with each other by overlapping or by the fitting of projections and recesses together. The interlock is provided by the physical barrier to movement the pins create.
The Network aspect is achieved through the connection and cooperation of the pin array which allows the object to be held securely.
The present design of the PIN vise reproduces a shape through an array of pins. In a PIN vise according to the present invention, the pins are in physical contact with each other and fit flush together, allowing the pins to be clamped from the top and held in place due to the compressive force and resulting friction created by their intimate contact.
According to an embodiment of the present invention, a vise includes a base and two opposed jaws. At least one of the jaws may be movable with respect to the other so that an object can be gripped therebetween.
The at least one of the two opposed jaws may include a frame having a bottom side and two opposed sides tapering towards the bottom side. The jaw may further include an array of polygon-shaped pins stacked in a bundle, the pins being parallel to one another and disposed on and received by the bottom side and within the frame.
Each pin may have a cross-sectional shape such that when slacked together, the pins fit flush with one another along a minimum functional distance lengthwise and an area defined by the frame is tiled by the pins without any substantial gaps therebetween.
Each pin has an inner end in cooperation for conforming to an object and gripping the object and an outer end against which the pin can be pushed. In some version, the inner end and the outer end are the same and interchangeable.
When stacked together, the pins may be oriented such that the pins form a network and the tapering opposed sides direct force vectors to increase a pin-to-pin clamping force. The pins may be in contact with one another to an extent such that each pin may assert a clamping force against its neighboring pins.
The frame may further include a top plate for clamping down on the pins such that the pins are held in place by the frame.
In some version, the other jaw may be a flat jaw.
In some version, the top plate may have a bottom surface with grooves for complementing and receiving the pins. In other versions, the top plate may have a flat bottom surface to be in contact with the flat sides of the pins.
In some version, the frame may include a bottom plate as the bottom side and a pair of angled plates forming the two angled sides, the bottom plate disposed between the pair of angled plates.
The top surface of the bottom side of the frame may be flat or with grooves for receiving the pins. The slopes of the two opposed sides of the frame are different.
In some version, the pins may each have an identical cross-sectional shape. The shape may be triangle, square or hexagon, or any other shape that can tile a plane without having any overlaps or leaving any gaps.
In some versions, the array of pins may have at least two different cross-sectional shapes. The pins within the external layer in contact with the frame may have a partial or incomplete shape of a triangle, hexagon or trapezoid, or other shapes.
In some version, the pins may have the same cross-sectional shape but some may have different sizes.
The concept of the design of a PIN vise in accordance with an embodiment of the present invention is shown in
The two jaws may be same. The jaws may also be different. For example, a vise may include a jaw with pins and a flat jaw. A vise may include two jaws with pins but the pins on one jaw may be different from the pins on the other jaw.
In one embodiment, the frame 140 includes a bottom side 108 and two opposed sides 110, 110′ tapering towards the bottom side 108. The tapered sides 110, 110′ may have the same or different slopes. The bottom side may have an upper surface having grooves 112 that match the shapes of the pins for the pins to rest on.
A bundle of pins are clamped by the frame. The pins may have substantially the same cross-sectional shape. The pins may also have different cross-sectional shapes so long as when stacked together, the side surfaces of the pins are in contact with one another and there are no substantial gaps between the pins.
The pins may have the same length or different lengths. Each pin has two ends and multiple side surfaces. Two ends may be similar and not distinguishable. Each pin may have a substantially same dimension along its length. When the pins are bundled together, the pins are parallel to one another.
The frame may further include a top brace placed on the top of the pins. The top brace may be tightened by threading members such as screws. The top brace works in corporation with the opposed tapering sides and the bottom side for clamping down the pins such that the pins are held in place.
When the pins are clamped in place within the frame, one end may be called an outer end. The end for gripping the object may be called an inner end.
The slope of the tapering sides of the frame may be selected according to the shape of the pins and the orientation of the pins. In one example, the pins are oriented such that each side of the pin is pushing against a side surface of another pin or the frame. There will be no side which is oriented vertically. In other words, all sides of the pins are oriented at an angle with respect to a vertical axis.
In one embodiment, as shown in
There are two principal forces to assess: 1) the clamping force which retains the pins in a desired position (Pin Clamping Force), and 2) the damping force of the vise on the part to be held (Vise Clamping Force). The pin clamping force is determined by the force applied to the top brace, achieved by simple screw force for example, and the vise clamping force is applied using a vise handle, seen in
The jaw may include a mounting plate 104. The mounting plate 104 is similar to a flat jaw 10 of a common vise shown in
In another embodiment, the vise is comprised of a number of independent members. A pair of angled plates 128, 130 resting on the mounting plate 104, along with the mounting plate, form a tapered frame in which an array of pins 114 are held. Directly on the top of the mounting plate and between the pair of angle plates is a fixed plate 132, the surface of which is designed with grooves 112 that match and receive the shape of the pins. Likewise, an adjustable insert plate 124 is designed with a surface having grooves 126 that mate to and receive the shape of the pins to be disposed between the array of pins and a top brace 120.
The adjustable insert plate 124 is not rigidly held, but rather it rests on top of the pins. It can be clamped down by simple screw force or by any other standard means such as cam-action, toggle or hydraulic clamping. The top brace 120 may be clamped by a two-point clamping using two threaded members or by a three-point clamping using three threaded members. The top brace 120 may also be clamped by a uniform clamping by a toggle. The adjustable insert plate 124 may be made from materials with high hardness, such as brass or steel, for the benefit of its rigidity.
To set the vise, an object is placed between two jaws. In the example shown in
The geometry of the pins can act as a locating surface for elevating a part or holding flat parts at a particular angle, e.g., a 45 degree angle using the square pins, as shown in
One of the jaws may be flat 400, working together with a pin vise jaw 100, as shown in
Many variations may be applied to the design. Instead of using square pins, other shapes may be used. The shapes of the pins may be triangle, square, rectangle, hexagon, or any shape that can tile a plane without having any overlaps or leaving any appreciable or substantial gaps. The size of the pins can be varied to produce “high-definition” workpiece holding. The pin material can be readily changed to a softer type for delicate workpieces. The length of the pins can be adjusted as well.
The presently disclosed design makes exchange of the pins extremely simple, and the exchange can be done within minutes to reset the pin array. With the addition of a simple setup jig, that time could be reduced greatly.
The PIN vise was found to be more resistant to an applied torque on a spherical part than flat jaws or the more commonly used V-blocks. As shown in
Many possibilities of applications of the present invention exist outside of workpiece holding in manufacturing. This basic design can be applied in any industry that requires complex surfaces which change on a regular or semi-regular basis. For example, the technology could be modified and advanced for use in applications such as vacuum forming or molding for packaging in shipping, where the product to be shipped is used to create a positive mold and the pins are retained in the shape by clamping. Large companies in the thermoforming industry are actively engaged in research to develop technology to eliminate the need for back drilling. Some have attempted to use nano-foamed metals instead of traditional castings as the starting block for the mold piece. The holes are too small, however, and clog too quickly at the molecular level as the device is used, even in clean rooms. Alternatively, 3D printing is capable of complex geometries, but it is limited and/or costly for production operations.
The disclosed design has been demonstrated to allow for fine detail replication, and that without any refinement for the purpose. Indeed, the very same prototype, which was used to hold objects, was also used in vacuum forming for proof-of-concept. The greatest drawback is that highly smooth objects cannot be created as with machined molds. Although it is potentially viable that the pins may be machined and still provide some benefit by the reduction in hole drilling, non-critical surface detail may not require such processing.
For example, when shipping items, the appearance and detail replication is not of first-importance. Function is the primary necessity. Competitor products in the packing industry include enclosed-bag foam, bubble wrap, brown paper wadding, air packs, Styrofoam peanuts, and biodegradable peanuts. These items have a similar function of filling volume rather than directly forming to the product(s). If a customizable form could be created to shape sheet plastic to any desired geometry, the space requirement for storage and the commensurate waste would be greatly reduced.
As will be clear to those of skill in the art, the embodiments of the present invention illustrated and discussed herein may be altered in various ways without departing from the scope or teaching of the present invention. Also, elements and aspects of one embodiment may be combined with elements and aspects of another embodiment. It is the following claims, including all equivalents, which define the scope of the invention.
This application claims priority from U.S. Provisional Patent Application Ser. No. 62/505,464, filed May 12, 2017, the entire content of which is incorporated herein by reference.
Number | Date | Country | |
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62505464 | May 2017 | US |