Group 25 - Black and Decker Variable Speed Orbital Jigsaw
- This year (2011) in MAE 277, our group (25) has been given the honor of dissecting and analyzing a Black and Decker JS660 Variable Speed Orbital Jigsaw. With the completion of this project, we hope to understand the components and inner workings of an Orbital Jigsaw, as well as fully comprehend the manner with which we are expected to go about collecting and presenting data and information to future employers/coworkers. Our key points that we will be hitting on for the duration of this project will be Project Planning, Product Dissection, Product Analysis, Product Explanation, and Delivery.
- Throughout the length of the semester, Group 25 has attempted to investigate a variety of engineering considerations and decisions of the Black and Decker Variable Speed Orbital Jigsaw JS660. These considerations were analyzed during various stages of the disassembly and reassembly processes. At the initial stages of the project, the group, as a whole, possessed a limited knowledge of the internal components and functions of the product. However, as the project continued to progress the group became increasingly familiar with the factors that shaped the final design. This subsequently enabled the group to enact appropriate revisions to the design in relation to the economic, environmental, societal, and global factors.
- In an attempt to gain further insight into the inner workings of the jigsaw, the product was disassembled. The dissection process permitted the determination of the jigsaw’s subsystems and method of manufacturing. These subsystems may be primarily separated into three sections: Electrical, Mechanical, and Cooling. Each subsystem was determined to consist of a variety of components, which are connected either physically or by energy or mass transfer. Ultimately, the group concluded that the arrangement of the components and subsystems was largely dictated by the flow of energy. Thus, the electrical system inputs the electrical energy from an external source. This energy is subsequently converted, by the mechanical subsystem, to rotational and then oscillating linear mechanical energy. The cooling subsystem serves to reduce the temperature of the motor and direct debris from the blade.
- The individual components, resulting from the dissection process were then further analyzed. This investigation enabled the determination of the individualized function and form of each component. For instance, the scotch yoke mechanism, the means by which the jigsaw converts rotational mechanical energy to oscillatory mechanical energy, proved to be particularly essential to the operation of the jigsaw. The mechanism consists of the reciprocating shaft, cam gear and roller. As the cam gear rotates, due the electrical motor, the roller offsets the reciprocating shaft in a sinusoidal fashion. This permits the blade to oscillate. Without the scotch yoke mechanism, or an equivalent alternative, the jigsaw would rotate in relation to the electric motor, since the rotational energy would not be appropriately converted. Individual analysis of the components also permitted the determination of the manufacturing process used during production. From a general perspective, the mass-produced nature of the product allows the implementation of die casting and injection molding to manufacture the metal and plastic components, respectively.
- The reassembly process permitted the group to synthesize the information gathered throughout the project. This information subsequently enabled the group to devise a multitude of design revisions for the product. The design revisions suggested largely attempted to improve the jigsaw’s functionality or ease of use. These revisions were suggested in consideration of the intended audience of the product. This audience was based on the likelihood of a particular consumer purchasing and using the product. Hence, we may conclude that the most probable consumer of the jigsaw is the household handyman or do-it-yourselfer.
- Ultimately, we may conclude that the Black and Decker Variable Speed Orbital Jigsaw JS660 is a fairly complex power tool which relies on the arrangement of subsystems and components in order to successfully transfer and convert the flow of energy. This enables the jigsaw to perform its intended overall function: to remove the desired material.
- Brian Bergh - Project Manager
- Ariel Reginer - Communication Liaison
- Travis Burt - Technical Expert
- Colin Lawson - Computer Expert
The purpose of Gate 1 is to provide an initial assessment of the product and the group. This section attempts to profile the variety of engineering decisions made during the design process. Thus, the gate isolates the developmental history of the tool and the energy flow in relation to such factors as consumer interaction and usage. A list of possible product alternatives is detailed and analyzed with regard to the specifications of the Black and Decker Variable Speed Orbital Jigsaw.
Gate1: Product Planning contents include:
- Work Proposal
- Management Proposal
- Product Archaeology
The purpose of Gate 2 is to analyze the product's components by the means of a disassembly process. The gate also enables the determination of the jigsaw's subsystems and the role each component performs in order to carry out the primary function of the tool.
Gate2: Product Dissection Contents include:
- Cause for Corrective Action
- Product Archaeology: Product Dissection
The purpose of Gate 3 is to investigate the characteristics and engineering considerations of each components with the product. This investigation enables the determination of the manufacturing processes implemented during production, the form of the component and the part function. This information permitted the suggestion of several disign revision, which alter the product on the component level.
Gate3: Product Analysis Contents include:
- Product Management
- Product Archaeology
Gate4: Product Explanation Contents include:
- Product Management
- Product Archaeology
The purpose of this gate is to detail the material depicted with the oral presentation portion of the project.
Gate5: Oral Presentation contents include: