Jacobs Vehicle Systems

Last updated
Jacobs Vehicle Systems
Type Subsidiary of Cummins
IndustryManufacturing
Headquarters Bloomfield, Connecticut,
United States
Area served
Worldwide
Parent Cummins
Website http://www.jacobsvehiclesystems.com

Jacobs Vehicle Systems, Inc. is an American company that engineers, develops and manufacturers commercial vehicle retarding and valve actuation technologies. The company produces light-duty, medium-duty, and heavy-duty engine brakes, recreational vehicle exhaust brakes, aftermarket parts and tune-up kits to heavy-duty diesel engine manufacturers in its domestic market in America, as well as in Asia and Europe. The company was incorporated in 1990 and is based in Bloomfield, Connecticut. Jacobs Vehicle Systems, Inc. operates as a subsidiary of Altra Industrial Motion Corporation. [1] On 9 February 2022, Cummins, Inc. announced an agreement to acquire Jacobs Vehicle Systems from Altra. [2]

Contents

History

The Jacobs Engine Brake has been on the market since 1961, better known as the “Jake Brake”. The value of an engine retarder had been recognised many years earlier. In England in 1905, the motor car manufacturer Rover provided on its "16-20" model an auxiliary camshaft and modified exhaust cams which, when selected via a camshaft pedal, lifted the exhaust valve twice to every revolution of the shaft, causing air to be taken in from the exhaust pipe on every downward movement of the piston, compressed on the upward stroke, and then exhausted. Rover declared that "the braking effect of this device is very pronounced - in fact, for all ordinary purposes it can be used without recourse to the friction brakes". Some 26 years later, and despite the advances in friction braking, the need for such a system was experienced by inventor Clessie L. Cummins. In August 1931, Clessie Cummins, Ford Moyer, and Dave Evans driving a Cummins diesel powered Indiana truck from New York to Los Angeles attempted to set a new truck speed record across the continent. All went well until the descent of the Cajon Pass leading into San Bernardino, CA, a long and steep gravel road which almost led to the demise of the truck and its driver, Clessie Cummins. [3] In 1955, Clessie began studying what might be done to turn his engine into an effective “brake”, or vehicle retarder. An idea for a practical method came to Clessie in 1957. The idea revolved around taking advantage of perfectly timed motion already built into Cummins and Detroit Diesel engines; these engines have a third cam on the main camshaft that activates the fuel injector of each cylinder. A simple retrofit mechanism could transfer motion to open the exhaust valve. A patent was ultimately granted by the U.S. Patent Office. Although the principles were proven by mechanically transferring the injector motion, a more practical method was to use a fully hydraulic motion and force transfer. The first retarder housings of the prototype design were installed on a Cummins diesel engine in a truck owned and operated by the Sheldon Oil Company. [4] The initial run with the engine brake was to one of their plants just at the eastern base of the grade, down the Sierras on U.S. Highway 50 near Lake Tahoe.

In April 1960, Jacobs Manufacturing Company made the decision to establish its new Clessie L. Cummins Division, (now named Jacobs Vehicle Systems) for the manufacture of the engine brake. The first production units for the Cummins NH series engines left the factory in 1961, followed shortly by a brake for the Detroit 71 series. [5]

The firm split in 1986 and chuck manufacturing now takes place in Clemson, South Carolina and engine brake production in Bloomfield, CT. [6]

How A Jake Brake Works

A “Jake Brake” is an engine compression release brake used especially for steep hill downgrades. The Jake Brake opens the exhaust valves when the piston is near top dead center (where ignition normally occurs). On the upstroke, the piston compresses the air in the cylinder to 1/15th its original volume, which creates drag on the engine. The Jacobs Engine Brake then releases the compressed air and the energy stored in it before it can push back on the piston during the down stroke. The Jake Brake turns a power producing engine into a power absorbing air compressor and in turn, causes the truck to slow down. Inside of the truck, the driver can choose how many cylinders to activate; the more cylinders activated, the more slowing of the truck.

Jacob Vehicle System Technologies

Exhaust Brakes

Uses back pressure to increase braking power by restricting the flow of exhaust gasses and increasing backpressure inside the engine. The increased backpressure in the engine creates resistance against the pistons, slowing the crankshafts rotation and helping to control the vehicle speed. [7]

Bleeder Brakes

The bleeder brake is a simplified version of traditional engine brakes. When the bleeder brake is turned on, a piston extends to its full stroke and stays there, holding the exhaust valve open a small, fixed distance throughout the entire four-stroke engine cycle. Since the bleeder brake only holds the exhaust valve open a fixed distance, it can be designed so that it does not put any load on the camshaft and most of the overhead components. [8]

Compression Release Brakes

When activated, the Jacobs Engine Brake opens the exhaust valves near the top of the compression stroke, releasing the highly compressed air through the exhaust system. Little energy is returned to the piston, and as the cycle repeats, the energy of the trucks forward motion is dissipated, causing the truck to slow down. [9]

Variable Valve Actuation

Allows for real-time adjustment to valve opening and closing for precise control of valve motion. By creating a hydraulic link between the cam and the valve, VVA tunes the engine across its operating range. [10]

High Power Density

Provides large displacement retarding power in small and medium displacement engines. HPD consists of two dedicated rocker arms and two collapsible bridges per cylinder, which enables a second braking event during each engine cycle. [11]

Customers

C&C Trucks, CNHTC, Cummins, DAF, Daimler, Detroit Diesel, Deutz, DFM, Doosan, FAW, FOTON, FUSO, HINO, HYUNDAI, Navistar, Paccar, SDEC [12]

Related Research Articles

<span class="mw-page-title-main">Reciprocating engine</span> Engine utilising one or more reciprocating pistons

A reciprocating engine, also often known as a piston engine, is typically a heat engine that uses one or more reciprocating pistons to convert high temperature and high pressure into a rotating motion. This article describes the common features of all types. The main types are: the internal combustion engine, used extensively in motor vehicles; the steam engine, the mainstay of the Industrial Revolution; and the Stirling engine for niche applications. Internal combustion engines are further classified in two ways: either a spark-ignition (SI) engine, where the spark plug initiates the combustion; or a compression-ignition (CI) engine, where the air within the cylinder is compressed, thus heating it, so that the heated air ignites fuel that is injected then or earlier.

<span class="mw-page-title-main">Miller cycle</span> Thermodynamic cycle

In engineering, the Miller cycle is a thermodynamic cycle used in a type of internal combustion engine. The Miller cycle was patented by Ralph Miller, an American engineer, U.S. Patent 2,817,322 dated Dec 24, 1957. The engine may be two- or four-stroke and may be run on diesel fuel, gases, or dual fuel.

<span class="mw-page-title-main">Two-stroke engine</span> Internal combustion engine type

A two-strokeengine is a type of internal combustion engine that completes a power cycle with two strokes of the piston during one power cycle, this power cycle being completed in one revolution of the crankshaft. A four-stroke engine requires four strokes of the piston to complete a power cycle during two crankshaft revolutions. In a two-stroke engine, the end of the combustion stroke and the beginning of the compression stroke happen simultaneously, with the intake and exhaust functions occurring at the same time.

<span class="mw-page-title-main">Four-stroke engine</span> Internal combustion engine type

A four-strokeengine is an internal combustion (IC) engine in which the piston completes four separate strokes while turning the crankshaft. A stroke refers to the full travel of the piston along the cylinder, in either direction. The four separate strokes are termed:

  1. Intake: Also known as induction or suction. This stroke of the piston begins at top dead center (T.D.C.) and ends at bottom dead center (B.D.C.). In this stroke the intake valve must be in the open position while the piston pulls an air-fuel mixture into the cylinder by producing a partial vacuum in the cylinder through its downward motion.
  2. Compression: This stroke begins at B.D.C, or just at the end of the suction stroke, and ends at T.D.C. In this stroke the piston compresses the air-fuel mixture in preparation for ignition during the power stroke (below). Both the intake and exhaust valves are closed during this stage.
  3. Combustion: Also known as power or ignition. This is the start of the second revolution of the four stroke cycle. At this point the crankshaft has completed a full 360 degree revolution. While the piston is at T.D.C. the compressed air-fuel mixture is ignited by a spark plug or by heat generated by high compression, forcefully returning the piston to B.D.C. This stroke produces mechanical work from the engine to turn the crankshaft.
  4. Exhaust: Also known as outlet. During the exhaust stroke, the piston, once again, returns from B.D.C. to T.D.C. while the exhaust valve is open. This action expels the spent air-fuel mixture through the exhaust port.
<span class="mw-page-title-main">Atkinson cycle</span> Thermodynamic cycle

The Atkinson-cycle engine is a type of internal combustion engine invented by James Atkinson in 1882. The Atkinson cycle is designed to provide efficiency at the expense of power density.

<span class="mw-page-title-main">Compression release engine brake</span> Mechanism of some diesel engines

A compression release engine brake, compression brake, or decompression brake, frequently called a Jacobs brake or Jake Brake, is an engine braking mechanism installed on some diesel engines. When activated, it opens exhaust valves to the cylinders, right before the compression stroke ends, releasing the compressed gas trapped in the cylinders, and slowing the vehicle.

<span class="mw-page-title-main">Engine braking</span>

Engine braking occurs when the retarding forces within an engine are used to slow down a motor vehicle, as opposed to using additional external braking mechanisms such as friction brakes or magnetic brakes.

<span class="mw-page-title-main">Cummins B Series engine</span> Motor vehicle engine

The Cummins B Series is a family of diesel engines produced by American manufacturer Cummins. In production since 1984, the B series engine family is intended for multiple applications on and off-highway, light-duty, and medium-duty. In the automotive industry, it is best known for its use in school buses, public service buses in the United Kingdom, and Dodge/Ram pickup trucks.

Manifold vacuum, or engine vacuum in an internal combustion engine is the difference in air pressure between the engine's intake manifold and Earth's atmosphere.

An exhaust brake is a means of slowing a diesel engine by closing off the exhaust path from the engine, causing the exhaust gases to be compressed in the exhaust manifold, and in the cylinder. Since the exhaust is being compressed, and there is no fuel being applied, the engine slows down the vehicle. The amount of negative torque generated is usually directly proportional to the back pressure of the engine.

Clessie Lyle Cummins was the founder of the Cummins Engine Co. He was an entrepreneur who improved on existing diesel engines, created new diesel engine designs, was awarded 33 United States patents for his inventions, and set five world records for endurance and speed for trucks, buses and race cars.

<span class="mw-page-title-main">Retarder (mechanical engineering)</span>

A retarder is a device used to augment or replace some of the functions of primary friction-based braking systems, usually on heavy vehicles. Retarders serve to slow vehicles, or maintain a steady speed while traveling down a hill, and help prevent the vehicle from "running away" by accelerating down the hill. They are not usually capable of bringing vehicles to a standstill, as their effectiveness diminishes as vehicle speed lowers. They are usually used as an additional "assistance" to slow vehicles, with the final braking done by a conventional friction braking system. As the friction brake will be used less, particularly at higher speeds, their service life is increased, and since in those vehicles the brakes are air-actuated, it helps to conserve air pressure too.

The following outline is provided as an overview of and topical guide to automobiles:

<span class="mw-page-title-main">Volvo FH</span> Motor vehicle

The Volvo FH is a heavy truck range manufactured by the Swedish company Volvo Trucks. It was originally introduced in late 1993 as the FH12 and FH16. FH stands for Forward control High entry, where numbers denominate engine capacity in litres. The FH range is one of the most successful truck series ever having sold more than 400,000 units worldwide.

<span class="mw-page-title-main">Uniflow steam engine</span>

The uniflow type of steam engine uses steam that flows in one direction only in each half of the cylinder. Thermal efficiency is increased by having a temperature gradient along the cylinder. Steam always enters at the hot ends of the cylinder and exhausts through ports at the cooler centre. By this means, the relative heating and cooling of the cylinder walls is reduced.

<span class="mw-page-title-main">Two-stroke diesel engine</span> Engine type

A two-stroke diesel engine is a diesel engine that uses compression ignition in a two-stroke combustion cycle. It was invented by Hugo Güldner in 1899.

Internal combustion engines come in a wide variety of types, but have certain family resemblances, and thus share many common types of components.

<span class="mw-page-title-main">Internal combustion engine</span> Engine in which the combustion of a fuel occurs with an oxidizer in a combustion chamber

An internal combustion engine is a heat engine in which the combustion of a fuel occurs with an oxidizer in a combustion chamber that is an integral part of the working fluid flow circuit. In an internal combustion engine, the expansion of the high-temperature and high-pressure gases produced by combustion applies direct force to some component of the engine. The force is typically applied to pistons, turbine blades, a rotor, or a nozzle. This force moves the component over a distance, transforming chemical energy into kinetic energy which is used to propel, move or power whatever the engine is attached to. This replaced the external combustion engine for applications where the weight or size of an engine were more important.

<span class="mw-page-title-main">4 VD 14,5/12-1 SRW</span> Motor vehicle engine

The 4 VD 14,5/12-1 SRW is an inline four-cylinder diesel engine produced by the VEB IFA Motorenwerke Nordhausen from 1967 to 1990. The engine was one of the standard modular engines for agricultural and industrial use in the Comecon-countries. Approximately one million units were made.

References

  1. https://www.nasdaq.com/article/altra-industrials-unit-to-merge-with-fortives-as-business-cm1027557 [ bare URL ]
  2. "Cummins to acquire engine braking and cylinder deactivation company to advance its path to a zero emissions future".
  3. Cummins, Clessie (1967). My days with the Diesel. Philadelphia and New York: Chilton Books. p. 131.
  4. "Cummins Diesel History". Mr. Sharkey.
  5. "1961: CUMMINS NH220 855-CUBIC-IN. ENGINE". Overdrive Retro.
  6. Cummins, Clessie (1967). My days with the Diesel. Philadelphia and Toronto: Chilton Company and Ambassador Books, Ltd.
  7. "Exhaust Brakes". Jacobs Vehicle Systems.
  8. "Jacobs Vehicle Systems Develops "Bridge Brake" Technology". truckpartsandservice.com. Truck Parts and Services.
  9. "Compression Release Brakes". Jacobs Vehicle Systems.
  10. "Variable Valve Actuation". Jacobs Vehicle Systems.
  11. "High Power Density". Jacobs Vehicle Systems.
  12. "Jacobs Vehicle System Customers". Jacobs Vehicle Systems.