Berkshire precision tool

This application claims the benefit of and incorporates by reference essential subject matter disclosed in U. Provisional Patent Application No. The present invention relates to end mills in general, and to single piece toroidal end mills in particular. There is a need for an effective alternative to current products that can utilize the rotational speeds and feed rates of modern machine tools in a production environment.

Every machine shop is looking for ways to maximize its productivity within the operating parameters of its machine tools. Many cutting tool companies are bringing tools to market that, though very productive in theory, are often not practical in all applications and environments given the horsepower, torque, or rigidity restrictions required to properly utilize their geometries. Many of the machine tools currently in use, do not have the horsepower or torque capabilities required by these milling tools.

There is also a need for a tool that can help the domestic mold making industry. That tool must be able to machine small mold cavities in a productive manner. It is known to use a toroidal end mill to rough pockets, cavities and cores at accelerated speeds and feeds over those typically used with a conventional style end mill. Another great use for a toroidal end mill is the finishing of a flat surface. Aggressive feed rates are also possible with a single axis movement.

These movements permit the machining of hardened material, thereby creating an additional benefit. Prior art toroidal end mills typically use carbide inserts. End mills with carbide inserts have several drawbacks, including: 1 increased tool cost; 2 potential for relative movement between an insert and the tool holder during the machining process, which can degrade the ability of the tool to hold specifications; 3 they typically have a negative rake angle that can undesirably plow work piece material during the machining process; 4 they typically have a shock value in machining that is less than a solid tool, and are therefore more susceptible to damage e.

Where inserts are not used, manufacturers will often use a solid, ball nosed end mills. These ball nosed end mills have disadvantages as well. A ball nose end mill has a zero surface feet per minute SFM in the center of the end mill. In addition, when a ball mill is cutting material in a side movement the center drags, or when operating in a plugging or inward movement, the center of the ball mill comes under extreme force. Ball mills also often leave a less than desirable surface finish.

According to the present invention, a one-piece toroidal end mill having an axis of rotation is provided. The end mill includes a shank section and a fluted section. The shank section extends along the axis of rotation. The fluted section extends along the axis of rotation, and has a first end, a second end opposite the first end, an outer surface, and a plurality of teeth.

The first end is integrally attached to the shank section. Each of the plurality of teeth has a cutting surface and a shoulder surface. The cutting surface includes a cutting edge, and extends from the tip toward the shank section, between and contiguous with the shoulder surface and the outer surface.

The shoulder surfaces intersect with one another to form a center void disposed between the cutting surfaces. The present invention provides several advantages over prior art end mills with or without inserts. First, it is our experience that the present invention end mill increases the effective machining of machines with lower horsepower and torque capabilities.

Such machines can achieve typically higher cubic inch removal rate per minute of operation with the present invention than they could achieve using a conventional end mill or insert standard tool. The higher cubic inch removal rates are achieved with light depth of cut e. It is our further experience that accelerated speeds and feeds greater than that conventionally used for a given material, with shallow depth of cut, are possible with the present invention end mill.

With the present invention solid design end mill, material specific end mills can be produced and remanufactured to meet the manufacturing needs without costly retooling. The present invention end mills can also be readily manufactured in forms having more than two flutes, thereby further increasing the feed rates possible with the tool.

These and other features and advantages of the present invention will become apparent in light of the drawings and detailed description of the present invention provided below. Apart from apparel, Berkshire owns many other consumer products companies including Forest River, a maker of recreational vehicles; Duracell, the worldwide maker of alkaline batteries; Albecca Inc. FlightSafety provides high-tech training to pilots and aircraft maintenance technicians using advanced flight simulator technology.

In addition, Flight Safety designs and manufactures flight simulators for their own use as well as to sell to airlines and military organizations. NetJets operates as a shared ownership program for customers wanting the scale, flexibility, and access to a large fleet of aircraft.

Customers acquire a specific percentage of the aircraft allowing them to use it for a set number of hours per year. TTI is a worldwide distributor of small electronic components, usually ordered in bulk, that are used in a variety of different applications including electronic manufacturing services, design and systems engineers, as well as military and commercial customers.

Their largest retailing business is their Berkshire Hathaway Automotive operation which as of had 82 dealerships located throughout the United States, particularly in Arizona and Texas. Their most notable retailing business, Nebraska Furniture Mart, operates four retail stores with a total of 4.

While the growth of the organization has slowed in recent years, something that was bound to happen, the strength and competitive advantage of Berkshire Hathaway continues to be rivaled by very few. Updated on Jul 13, , pm.

Sign in. Log into your account. Privacy Policy. Sign up. Password recovery. Thursday, January 13, Forgot your password? Get help. Create an account. Traits Of An Unfear Organization. Value Investing. Table of Contents show. Insurance 2. GEICO 2. Berkshire Hathaway Primary Group 2. Berkshire Hathaway Reinsurance Group 3. Railroad 3. He cited Berkshire's policy of letting its companies "deal individually with their own labor and personnel decisions.

About Special Metals workers in Huntington, W. Health care is among the biggest issues in the contract talks as the union tries to avoid paying more for a higher deductible insurance plan, United Steelworkers Local 40 President Chad Thompson said Thursday. Thompson said Sanders' office reached out to offer help to the striking workers.

He spoke to the senator by phone. He added that he appreciates Sanders offering support and hopes the increased attention will help talks advance. Thompson was disappointed not to reach a deal by Christmas. He said negotiations will restart next week, more than three months into the strike.