Gate4: Product Explanation

Purpose

It is the intent of Gate #4 to provide a detailed analysis and representation of the assembly process of the Black and Decker Variable Speed Orbital Jigsaw JS660. The gate will also specify a series of system-wide design revisions and examine the challenges within the group.

Figure 1: Black and Decker Variable Speed Orbital Jigsaw JS660

Project Management: Critical Project Review

Cause for Corrective Action

The final two weeks in a semester represent a convergent period of project deadlines. As such, the multitude of projects and exams between members has created a issue with work management with respect to the deviation of tasks between group members. Despite the need to begin the gate at an early date, induvidualized tasks may only be assigned to group members after considering their work external to the course. While this ensures that the project is ultimately completed by the deadline, it invariably results in the uneven distribution of work between the members. In an attempt to resolve this issue, the group discussed the situation in a meeting and decided to divide the work based on the current availability of the individual members. Then members who receive a decreased workload will subsequently be expected to provide additional assistance during the following gate. This permits the project to be completed in a timely manner and largely prevents problems from occurring in close proximity to the deadline. Within the realm of unresolved challenges and in consideration of the rapidly approaching oral presentation, the group must decide upon a presenter. While this is simply an a requirement with respect to the project, the situation has nonetheless managed to create a sense of turmoil within the group. Specific individuals have stated their desire to not be the presenter. However, other group members believe that these members would, in fact, be the ones best suited for the oral portion of the project. To combat this issue, the group has scheduled a meeting. During the confines of the meeting, individual members will discuss their opinions concerning the identity of the presenter and will contribute to the power point presentation.

Product Archaeology: Product Explanation

Products Components

The Black and Decker Variable Speed Orbital Jigsaw JS660 contains a multitude of components which must be reassembled to form the finished product. The components of the jigsaw are detailed in Figure 2.

Figure 2: Parts List

Black and Decker JS660 Parts List
Part Number	Part Designation	Component Function	Part Number (1)	Quantity	Visual Representation
1	Power Cord	The power cord is the long, black length of wire that extends from the back of the tool and serves to transfer electricity from an external source to the tool.	372067-16	1	Picture 1: Power Cord
2	Power Cord Clamp	The power cord clamp is a piece of metal which, when screwed into the body, restricts the movement of the power cord.	329301-00	1	Picture 2: Power Cord Clamp
3	Jigsaw body	The Jigsaw body is the plastic, black and orange exterior casing to the power tool. It consists of two halves. The body serves to contain the internal mechanical components of the jigsaw.	N/A	1	Picture 3: Jigsaw Body
4	Body Screw	The body screws attach the two halves of the Jigsaw body together. They have a 5/16 inch head diameter, and are 3/4 of an inch in length.	330045-02	8	Picture 4: Body screw
5	Reciprocating shaft Assembly	The Reciprocating shaft assembly is the metal extension connected to the blade holder. It is an essential component in the scotch yolk mechanism, which converts rotational to linear mechanical energy.	90517289	1	Picture 5: Reciprocating Shaft Assembly
6	Carbon Brushes	The Carbon brushes are black rectangular boxes that complete the circuit to the electric motor. They are clipped into the Jigsaw body.	N/A	2	Picture 6: Carbon Brushes
7	Armature Assembly	The Armature Assembly is the inner portion of the electric motor. The carbon brushes make contact to the armature in order to complete the circuit for the motor. When electricity is flowing through the system, the armature rotates rapidly within the Field assembly. Thus, the armature assembly serves to create rotational mechanical energy.	N/A	1	Picture 7: Armature Assembly
8	Field Assembly	The Field Assembly is the exterior portion of the electric motor. Electricity is transferred to the field assembly by means of two red wires. When power is flowing into the field assembly, the component causes the armature to rotate rapidly through the implementation of magnetic fields. As such, the field assembly serves to create rotational mechanical energy.	N/A	1	Picture 8: Field Assembly
9	Blade Guard	The Blade Guard is the length of steel which blocks the blade. The blade guard serves to protect the user from accidentally placing an appendage within the path of the blade.	N/A	1	Picture 9:Blade Guard
10	Trigger	The trigger regulates the flow of electrical energy within the tool. It is a black, rectangular box within the Jigsaw body.	585385-00	1	Picture 10: Trigger
11	Power Cord Clamp Screws	The Power Cord Clamp Screws attach the Power Cord Clamp to the jigsaw body.They have a 5/8 inch head diameter and are 1/4 inch in length.	370748	2	Picture 11: Screw
12	Base Plate	The Base Plate is the steel plate the jigsaw body rests upon. It serves to provide a stable platform for the tool during operation.	90517431	1	Picture 12: Base Plate
13	Angle Adjustment Lever	The Angle Adjustment Lever is the steel handle which adjusts the base plate angle. 90529814	90529814	1	Picture 13: Angle Adjustment Lever
14	Angle Adjustment Handle	The Angle Adjustment Handle is the black thumb tab attached to the end of the Angle Adjustment Lever. It serves to provide an easy point for the user to grip the angle adjustment handle.	90514276	1	Picture 14: Angle Adjustment Handle
15	Handle Screw	The Handle screw secures the Angle Adjustment Handle to the Angle Adjustment Lever. This screw has a 3/16 inch head diameter and is 9/16 inches in length.	330019-41	1	Picture 15: Handle Screw
16	Detent Spring	The Detent spring is contained within the base plate assembly. It permits the insert to move and lock within the base plate assembly.	90521871	1	Picture 16: Detent Spring
17	Lock Plate	The Lock Plate is the metal plate within the base plate assembly. It holds the insert, detent spring and angle indicator within the base plate assembly.	90521871	1	Picture 17: Lock Plate
18	Base Plate Bolt	The Base Plate Bolt connects the base plate to the jigsaw body.	90514219	1	Picture 18: Base Plate Bolt
19	Base Plate Washer	The Base Plate Washer is placed along the base plate bolt.	90514216	1	Picture 19: Base Plate Washer
20	Insert	The Insert is the black, plastic piece within the base plate assembly.	90514228	1	Picture 20: Insert
21	Angle Indicator	The Angle Indicator is the black, plastic dial which depicts the current base plate angle.	90514273	1	Picture 21: Angle Indicator
22	Blade Clamp	The Blade Clamp is the piece which holds the blade in place.	582593-00	1	Picture 22: Blade Clamp
23	Angle Plate	The Angle Plate is the white, plastic plate that rests on top of the base plate. It provides a level platform to attach the angle adjustment lever to the base plate.	N/A	1	Picture 23: Angle Plate
24	Blade Support	The Blade Support is the black, steel piece which guides the blade during movement.	90517418SV	1	Picture 23: Blade Support
25	Pivot Pin	The Pivot Pin is the steel pin within the blade support. It permits the blade support to rotate.	90514424	1	Picture 25: Pivot Pin
26	Roller	The Roller is the final gear within the gear train leading to the Reciprocating Shaft assembly. It functions to translate rotational mechanical energy to linear mechainical energy.	795688-00	1	Picture 26: Roller
27	Gear Train washer	The Gear Train washer is the small, steel washer within the gear train assembly. It functions to keep the roller is place.	823954-00	1	Picture 27: Washer
28	Dust Chute	It is the black, plastic tube that runs through the angle indicator and channels the material debris from the fan.	90514401	1	Picture 28: Dust Chute
29	Special lock plate bolt	The Special lock plate bolt is the long, black bolt within the lock plate. It functions to attach the lock plate to the base plate.	90514219	1	Picture 29: Special Lock Plate Bolt(1)
30	Cam Gear	The Cam Gear is the primary gear within the gear train assembly. It is connected to the roller. It serves to translate mechanical energy from rotational to linear.	N/A	1	Picture 30: Cam Gear
31	Counterweight plate	The Counterweight plate is the large, metal plate within the gear train assembly. It serves to dampen the resonance from the motion of the blade.	N/A	1	Picture 31: Counterweight
32	Connecting Plate	The Connecting Plate is the metal piece which connects the armature assembly to the gear.	N/A	1	Picture 32: Connecting Plate
33	Roller Needle Bearing	The Roller Needle Bearing is attached to the connecting plate. It functions to reduce the friction from rotation.	N/A	1	Picture 33: Roller Needle Bearing
34	Thrust Plate	The Thrust Plate is the metal plate between the connecting plate and the counterweight plate. It provides support between the motor and the gear assembly.	N/A	1	Picture 34: Thrust Plate
35	Snap Ring	The Snap Ring is the metal ring securing the gear to the gear train assembly.	N/A	1	Picture 35: Snap Ring
36	Cam	The cam is the black, plastic piece within the smart select assembly. It alters the position of the smart select plate.	90514375	1	Picture 36: Cam
37	Smart Select Casing	The Smart Select Casing is the black, plastic body that houses the components corresponding the Smart Select dial.	N/A	1	Picture 36: Smart Select Casing
38	Pc Board	The Pc Board is the black, plastic piece which holds the cam in place in the Smart Select Housing.	90517283	1	Picture 37: Pc Board
38	Smart Select Plate	The Smart Select Plate is the metal piece within the Smart Select Casing. It alters the movement of the blade in relation to the	90514354	1	Picture 38: Smart Select Plate
39	Duct	The Duct is the plastic, black piece which diverts the dust away from the blade.	90514324	1	Picture 39: Duct
40	Smart Select Dial	The function of this component is to alter the movement of the blade with respect to the dial setting.	N/A	1	Picture 40: Dial

Product Reassembly

Ease of assembly

To describe the difficulty of the product assembly, we have defined a relative complexity scale. The ease of assembly for this product will be rated on a scale between 1 through 5.

[1]- The tools required to complete the step are minimal and the process is simple to perform and conceptually comprehend.

[2]- The step requires the implementation of the correct tool. The task may be slightly conceptually or physically difficult to perform.

[3]- The step requires the use of one or more tools in a abstract manner. The task is conceptually difficult but may not be physically challenging.

[4]- This step one or more tools in addition to individual intuitiveness. The task is both conceptually and physically challenging for individuals who lack experience in the particular area.

[5]- The step requires multiple tools and strict procedural following. The process will be time consuming.

For the duration of the assembly description, the ratings given to each step will be notated by the scaled number encapsulated in square brackets (e.g. [5] ).

Tools Required:

The tools required for the dissection process are listed below.

• Hands
• T-10 Screwdriver
• T-20 Screwdriver
• Phillips head screwdriver
• 1/4 inch flat head screwdriver
• Needle nose pliers
• Snap Ring Pliers

Product Assembly

Table 1: Assembly Process

Assembly Process
Step	Description	Tool Required	Difficulty level	Visual Representation
1	Place the black smart select cam into the black smart select casing. Orient the longer thinner end of the cam away from the casing, such that the shorter end of the cam is going into the casing. Orient the tab on the flat piece of the cam to the 12 o’clock position, and place it into the inset hole in the hollow section of the casing.	Hand	[1] This step was rated to be a 1 because it is a simple combination of two parts, with a rotation accounting for orientation.	Picture 41: smart select casing
2	Place the pc board onto the cam shaft that is protruding through the hole. Orient the smaller alignment pin located on the pc board with the small hole located on the casing.	Hand	[1] This step was rated to be a 1 because it is a simple layering of parts.	Picture 42: smart select casing
3	Apply the smart select plate to the casing. Orient the plate with the protruding section of the plate facing the base, and the longer portion of the plate lying in the opposite direction of the base piece; insert into place.	Hand	[1] this step was rated to be a 1 because it is a simple insertion of a part.	Picture 43: smart select plate
4	Place the smart select dial assembly into the left side of the jigsaw body. Orient the smart select cam so it protrudes through the smart select dial hole out of the shell and the two screw holes on the casing align with the screw holes within the shell. The metal plate will fit into the grove allotted to that part within the body of the jigsaw. The part will be oriented vertically along with the shell.	Hand	[1] This step was rated to be a 1 due to the simplicity of the act of inlaying the smart select dial assembly into the jigsaw casing.	Picture 44: smart select dial assembly
5	With pliers, twist the smart select cam that is located within the hole in the shell and twist clockwise until it is no longer able to rotate. Note: Do not use excessive force.	Needle nose pliers	[2] This step was rated to be a 2 due to the need for the proper usage of a tool. The concept of the task is still fairly simple though.	Picture 45: shaft rotation
6	Take the smart select dial and orient the selector indicator tab to the 12 o’clock position in respect to the body, apply pressure and snap into place. Note: Hold the smart select assembly in place while doing so.	Hand	[1] This step was rated to be a 1 because although manual labor is necessary, it is not exceedingly difficult, and the concept is simple.	Picture 46: smart select dial
7	Place the reciprocating shaft assembly into the front portion of the jigsaw shell, about half an inch from the front of the shell. Orient vertically with the blade holder on the bottom, and insert into the appropriate groves in the shell, allotted for the shaft securing parts.	Hand	[1] This step was rated to be a 1 because it is a simple inlaying of a part.	Picture 47: reciprocating shaft assembly
8	Note that the dust cover has it’s own compartment as well within the shell, so take care that it sits in there correctly.	Hand	[1] This step was rated to be a 1 because it is a simple inlaying of a part.	Picture 48: Dust cover
9	Assemble the gear train. Start with the connecting plate; apply grease to the post.	Hand	[1] This step was rated to be a 1 because the application of grease is a simple concept and involves no manual labor	Picture 49: Connecting plate
10	Slide the roller needle bearing onto the post of the connecting plate. Orientation does not matter.	Hand	[1] This step was rated to be a 1 due to the simplicity of the task.	Picture 50: Needle berring
11	Place the thrust plate around the post of the connecting plate, through the cylindrical hole, not oval hole. The oval hole should line up with the circular hole in the connecting plate, such that the thrust plate lays lengthwise along the connecting plate. orientation does not matter, which side is “up” or “down”.	Hand	[1] This step was rated to be a 1 because this is a simple layering of parts.	Picture 51: thin metal plate
12	Apply grease to the inside of the large oval hole in the counter weight.	Hand	[1] This step was rated to be a 1 because applying grease is a simple concept and requires no manual labor.	Picture 52: counter weight addition
13	Orient the counter weight with the side with impressed corners facing the connecting plate and the smaller oval hole over the oval hole of the thrust plate.	Hand	[1] This step was rated to be a 1 because it is a simple layering of parts.	Picture 53: add weight
14	Place the post of the connecting plate inside the large oval hole of the counter weight.	Hand	[1] This step was rated to be a 1 because it is a simple layering of parts.	Picture 54: counter weight
15	Place the cam gear over the post and roller needle bearing, and rotate until fully seated. Place the cam gear with the spoke pointing away from the gear train assembly.	Hand	[1] This step was rated to be a 1 because it is a simple layering of parts.	Picture 55: large gear placement
16	In the grove in the center of the cam gear, apply the snap ring on the post from the connecting plate. Make sure the snap ring is fully seated in the retaining groove.	Snap ring pliers or needle nose pliers	[2] This step was rated to be a 2 due to the need for the implementation of the correct tool and its proper usage.	Picture 56: snap ring
17	Apply grease to the teeth of the cam gear.	Hand	[1] This step was rated to be a 1 due to the minimal manual labor required.	Picture 57: apply grease
18	Apply grease to the post on the cam gear.	Hand	[1] This step was rated to be a 1 due to the minimal manual labor required.	Picture 58: apply grease
19	Place the gear train washer on the post of the cam gear, and make sure that the washer is oriented concave up.	Hand	[1] This step was rated to be a 1 because it is a simple layering of parts.	Picture 59: gear train washer
20	Place the roller onto the gear post, with the smooth cylindrical part with no teeth oriented away from the gear train assembly.	Hand	[1] This step was rated to be a 1 because it is a simple layering of parts.	Picture 60: small gear
21	Orient the gear assembly so the roller is facing the reciprocating shaft assembly at the front of the jigsaw body. Turn the cam gear so that the roller is at the 3 o’clock position when the plate is vertical, with the thrust plate extending down. The hole in the gear train base should be oriented towards the bottom of the shell, and the gear train assembly should be placed into the shell vertically, aligning with the two screwholes in the smart select dial assembly. The gear train needs to be inserted at an angle, aligning the roller with the oval opening in the reciprocating shaft assembly. Then slide it into place.	Hand	[2] This step was rated to be a 2 because, although a tool was unneccesary, the concept of the orientation of the gear assembly is slightly more complex, and is key to the ease of insertion into the jigsaw body.	Picture 61: gear train assembly
22	Assemble the motor. Place the armature assembly inside the field assembly, with the fan end of the armature assembly on the opposite end of the field assembly as the wire and carbon brush.	Hand	[1] This step was rated to be a 1 due to the simple combination of parts, no skills required.	Picture 62: motor assembly
23	Orient the fan towards the gear train, and make sure the numbered, flat, portion of the field assembly is facing up. The gear train will need to be raised out of the shell slightly in order to allow the armature gear shaft to fit into the hole allotted to it. From here the gear train and the motor need to be maneuvered together in order to settle them into the shell. Once the motor is settled into the jigsaw body, be sure to route the two red wires connected to the field assembly under the placement of the upper carbon brush between the plastic parts. Make sure the motor assembly is able to rotate freely.	Hand	[3] This step was rated to be a 3 because, although no tool is involved, it requires the maneuvering of multiple components simultaneously in order to work correctly. The concept of this step is fairly complex, and may possibly require the assistance of an additional person.	Picture 63: motor
24	Secure the gear train into the shell with the two 1 1/2 in screws. screw them into the screw holes allotted to them along the gear train.	Flat head screw driver	[2] This step was rated to be a 2 due to the implementation of a tool, and the need for its proper usage.	Picture 64: screws
25	Clip the carbon brushs into their places on either side of the copper portion of the armature assembly. Pressure needs to be applied in order for them to be snapped in properly, and the black wires connecting the carbon brushes to the field assembly need to be tucked underneath them.	Hand	[1] This step was rated to be a 1 because of the minimal manual labor needed to complete the task.	Picture 65: carbon brushes
26	Route the red wires up along the handle portion of the shell, note the picture, following the groves in the shell, and place the trigger assembly into the handle.	Hand	[1] This step was rated to be a 1 because it is a simple inlaying of parts.	Picture 66: red wires
27	The flat part of the trigger will be facing down with the trigger box on top of the platform. It will resemble an upside down T.	Hand	[1] This step was rated to be a 1 because it is a simple inlaying of parts.	Picture 67: trigger
28	Run the black power cord back down along handle, routed along the same path as the red wires, and set between the orange screw holes. Nestle the black wedge portion of the power cord into the wall of the shell.	Hand	[1] This step was rated to be a 1 because it is a simple inlaying of parts.	Picture 68: power cord
29	Screw on the power cord clamp with the two small power cord clamp screws for it. Clamp on tighly.	Philips head screwdriver	[2] This step was rated to be a 2 due the the usage of a tool.	Picture 69: power cord plate
30	To place the blade support into the jigsaw cavity, the thrust plate in the gear train needs to be raised to its highest height, to allow space for the blade support to be slid into place. Refer to picture for orientation.	Hand	[1] This step was rated to be a 1 because it is a simple inlaying of a part.	Picture 70: blade support
31	Place the duct into the hollow portion of the blade support, be sure to insert at an angle.	Hand	[1] This step was rated to be a 1 because it is a simple inlaying of a part.	Picture 71: dust chute
32	Place the pivot pin into the hole of the blade support and duct in order secure it, be sure the hole in the duct and blade support are aligned.	Hand	[1] This step was rated to be a 1 due to the simplicity of the task.	Picture 72: blade support pin
33	Place the blade guard around the reciprocating shaft assembly, make sure the pins fit into the allotted holes. Refer to the picture for orientation.	Hand	[1] This step was rated to be a 1 due to the simplicity of the task.	Picture 73: blade guard
34	Assemble the base plate separately. Snap the insert into the rear most slot of the raised cylindrical portion of the base plate. Orient the insert such that the thicker ridged portion is towards the rear of the base plate, the end with the raised cylindrical portion. Apply pressure to snap the insert into place. Note: Make sure it is fully secure.	Hand	[1] This step is rated to be a 1 due to the simplicity of the task.	Picture 74: Insert
35	Add the lock plate and lock bolt onto the base plate by inserting it up through the bottom of the cylindrical portion of the base plate into the largest, center slot, with the bolt oriented vertically towards the top of the plate. The silver securing bolt on the lock plate should be oriented towards the back end of the base plate.	Hand	[1] This step is rated to be a 1 due to the simplicity of the task.	Picture 75: lock plate
36	Simultaneously add the detent spring and the angle plate atop of the base plate bolt. The spring should rest in the groves on the back portion of the insert and the index, oriented so the pointed part of the spring is pointed downward. Orient the index so that the thicker portion is towards the rear of the base plate, and the thinner flat surface is towards the front and on the bottom. Apply force to hold the spring in place while adding. Note: it needs to be manually held in place	Hand	[2] This step is rated to be a 2 because it requires heightened attention and physical involvement in order to keep the components in the correct placement within the assembly.	Picture 76: detent spring and insert
37	Screw the lever arm onto the base plate bolt in a counter clockwise motion, with the flatter side of the lever facing down, toward the base plate, and the rounded edged side facing up. Rotate until snug.	Hand	[1] This step is rated to be a 1 because of the simple task required.	Picture 77: lever arm
38	Add the base plate to the jigsaw body by inserting the lever arm into the allotted slot in the shell, with the raised edge of the base plate oriented towards the front of the saw, aligning the saw blade with the hole in the base plate. Insert a body screw into the insert on the base plate. Note: take care to make sure the deaton spring does not shift.	Hand	[1] This step is rated to be a 1 due to the simplicity of the task.	Picture 78: base plate
39	Move onto the angle indicator. Place the dust chute through the angle indicator with the numbers of the angle indicator oriented away from the mouth of the chute.	Hand	[1] This task was rated to be a 1 because this is a simple combination of parts.	Picture 79: dust chute and angle indicator
40	Place the angle indicator assembly into the bottom portion of the shell, below the motor, into the allotted place. Make sure the angle indicator is set at 0 in the viewing window on the jigsaw body (opposite side).	Hand	[1] This step was rated to be a 1 because it is a simple inlaying of parts.	Picture 80: angle indicator
41	Close the jig saw body by adding the right half of the shell. Be sure to close everything by hand first to make sure nothing is pinched in the tightening of the screws. Screw in all nine body screws into the body of the jigsaw.	T-20 screwdriver	[2] This is rated to be a 2 because of the implementation of the correct screwdriver and it's proper usage.	Picture 81: close shell
42	Finally flip the saw over to screw the thumb tab onto the lever arm of the base plate.	T-10 Screwdriver	[2] This step was rated to be a 2 because of the implementation of the correct screwdriver and it's proper usage.	Picture 82: thumb tab

Difficulty During the Assembly Process

Not many challenges were faced while assembling our product, since most of the steps were very straight forward and were of minimal complexity. We only ran into a few moments of hesitation before fully re-assembling it. the first occured while inlaying the gear train into the jigsaw casing; we had to figure out at what position the roller should be set in order for the gear train to be set into the mold. The second situation was while we were trying to inlay the motor. We had to figure out how to maneuver the other components in the most convenient and simplest fashion, for user friendliness, in order to allow the shaft assembly of the motor to be inset. Also, after laying the motor in, we noticed that something was off because our motor wasn't laying flat, and it took us a couple seconds to realize there were some wires irregularly bent under the motor. We then added that detail into the assembly process detail. And the final situation what while adding the base plate to the jigsaw shell, we were having trouble keeping the angle selecting dial (previously set in the shell) at 0. So we decided to switch the order of our steps to note that the base plate should be added before the angle indicator is set in place. Over all it was a fairly simple re-assembly though.

Original Assembly

The Black and Decker Varriable Speed Orbital Jigsaw JS660 was originally mass produced roboticly as well as production lines within in a factory. The separate parts were made and assembled individually, much like our assembly of the different components, and then put together within the body of the jigsaw in much of the same fashion as we did. Examples of this being the gear train and the base plate. The difference's between the manufacturer's process and our's is that there was no aid from robotics and and specialized tools that production line utilize for simple and increased production. Also, generally speaking, production lines only require a person to know how to assembly a few components and then it is sent to the next station and so on and so forth until the jigsaw is complete. We had the task of assembling the entire product and ensure it was assembled correctly for operation.

Assembly vs. Disassembly

The assembly process and disassembly process for this product is generally the same, although some slight variations in the order of things may occur. The individual components may be taken out all at once, then be dissected individually, or the different components could be broken down into their base parts as they are removed from the body cavity of the jigsaw. But overall, the basic order of the main components, such as the base plate, the motor, gear train, and reciprocating shaft, must be disassembled and assembled in the same order; following the flow of energy.

Design Revisions

Design Revision 1

Reciprocating and Jigsaw Combination

Diagram 3: Alternating Modes. Please note that the image is solely intended to provide a representation of the alternating modes. The body of the revision would be more similar to a jigsaw rather than the reciprocating saw depicted. (3)

In an attempt to improve the range of functionality of the Black and Decker Variable Speed Orbital Jigsaw, it is suggested that the original product be combined with a reciprocating saw. The design revision would feature a pivoting main section (scotch yoke) of the saw which could rotate to either 90 or 0 degrees in order to change the product into either a jigsaw or a reciprocating saw. The saw would also possess a locking mechanism in order to secure the saw in its intended use. The shaft of the motor would be attached to a small gear whose teeth are at a 45 degree angle. This would permit the primary gear to be oriented with the flat side perpendicular to the length of the motor's armature assembly. While the motor and the trigger would remain stationary, the scotch yoke mechanism would be able to rotate to change the form of the tool to either a jigsaw or a reciprocating saw. The tool would be held as if it is a reciprocating saw regardless of the orientation, in that one hand will be grasping the main portion of the body. The base plate, the component which provides a flat surface to push the jigsaw, would be likely be affixed to the the body of the tool. To ensure stability, the base plate would not detach. This would not interfere with the operation of the saw while it is in the reciprocating mode since the base place would be attached to the main body with the regard to permit proper handholds. In terms of audience, the revision would provide an increased appeal toward the household consumer. Since both the reciprocating saw and the jigsaw are specialized tools, whose intended purpose is designated for specific tasks only, the alteration would require the consumer to purchase only a single product. The societal factor for the design revision stem from the desire to increase the ease of use and the functionality of the product. The largest advantage of the product revision rests with the increase in functionality due to the fact that the revision is providing an additional function to the product. Since the household do-it-yourself-er likely does not require the use of either a jigsaw or a reciprocating saw frequently, the purchase of both tools represents a hassle. In addition, the household consumer is no longer forced to carry two tools to the job site. The revision thus reduces the required space to store the tools necessary to perform the functions of both tools. While the price of the product would increase, the overall price should be less than the combined prices of the two tools separately since there is component overlap. Thus, the design revision represents the cheaper option for the consumer rather than purchasing both a jigsaw and a reciprocating saw.

Diagram 1: Jigsaw Mode

Diagram 2: Reciprocating Mode

Design Revision 2

Alternative Energy Source: Propane

Another potential design revision for the Black and Decker jig saw would be to convert the power source of the jigsaw to propane. The design revision would include a tube traveling form the back end of the jigsaw, similar to where the power cord attaches now, to a propane tank that could be holstered on a belt. In order for this conversion to take place, a small propane engine would need to be manufactured or purchased from a supplier and implemented in the tool. Also, a type of ignition system would have to be developed to start the motor. A possibility for this could be similar to a striker on a grill. This change would remove the requirement for a power cord, making the jigsaw portable. Not only would this increase the saws portability, but also increase the saws range of operation limitless. If a larger propane storage tank was kept on the users vehicle, the jigsaw could be used in a variety of places where electricity is not available. This would address global factors by allowing the saw to be used in places without access to power outlets. Examples of these areas include rural areas, third world countries, and outdoors in general. Also, being that no company produce's a propane jigsaw, if this was the only company to produce a saw of this sort, buyers would have no other options which would increase sales. This utilization of propane would create a new aspect for customers and give them more options to choose from. Diagram 3 provides a representative image of the propane revision for a small engine.

Due to the changes to the structure and the motor, the new jigsaw design would likely cost more than the current one as such changes would require new factory equipment to create the product. In addition, the reliance on propane supply may negatively affect sales in areas were propane is scarce due to the fact that electricity will be usually be cheaper in said areas. Also, the propane powered jigsaw will likely be more complicated to operate, possibly alienating more casual users. Overall, even with these possible stated issues, the design would increase the number of areas in which the jigsaw is useful, apply to a specific consumer base, and ultimately increase profits.

Diagram 4: Propane Revision

Design Revision 3

Propulsion System

Diagram 5: Belt - Track Up

Lastly, another revision created was is intended to assist the user in feeding the saw into the material during the cutting process. This would be accomplished by creating driving system that would use two rubber belts that would run along either side of the base plate. One of the major selling points of the jig saw is its ability to allow freedom and mobility while cutting complex shapes. Taking this into consideration during the revision process, a plausible solution was formed to still allow users to keep that desired freedom. The drive system would be able to be used only when needed by the user. This could be accomplished by having the belts on a movable support that would easily raise or lower the belts above or slightly below the surface of the base plate by the switch of a lever. This new system would contain its own separate electric motor and the speed of the motor could be controlled by a simple dial allowing for various speeds depending on the material. There would be a roller at the front of this support and the driveshaft at the rear, just as a vacuum works to rotate the brush. In between the roller and drive shaft, there would be a supporting structure that would support the belt to restrict the belt from deflection. It was decided to use belts because the use of wheels would seem incapable of creating the amount of friction needed to drive the saw forward without them slipping. A set of belts that are supported along there complete contact area should provide plenty of friction and require less down force by the user on the unit. For a tool such as this, the typical user is not a construction worker, but a hobbyist, small craftsman, or “do it yourselfer” at home. Because of the lack of experience or other available tools to aid in cutting, this system can greatly contribute to this demographic of users.

Diagram 6: Belt - Track Down

One of the key advantages of this new system is that it would take less effort by the user during operation. Even though the jigsaw is fairly light, it takes some effort to push the saw while cutting through a material. This, in turn, would help reduce some of the fatigue on the user and create a more pleasurable experience using the tool. Another advantage of this system is that it would allow for a more accurate cut. When attempting to cut a straight line with a jigsaw, without the help of a straight edge, it can be very difficult due to the vibration from the reciprocating motion of the blade, on top of just trying to move an object in a straight line without any assistance. Because the drive belts would be operated by the same motor and rotating at the same speed, it could help keep the blade steadier and aid in creating a straighter cut. Though a straight cut can be accomplished by means of other tools such as a circular saw, not every consumer may own one of these tools. An option such as the drive system would help users limited on select tools. This propulsion system would contribute mostly to the societal factor due to the benefits of the reduced effort and aiding in a more preferable cut. While this may increase the cost of the product, the trade off for a tool that can better assist the user in these ways overcompensates for the new price difference. Another contributing factor is that this system would be easy to use for all customers in various countries.

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Citations

(1) Black and decker js660 type 1 jigsaw parts. (2011). Retrieved from http://www.ereplacementparts.com/black-and-decker-js660-type-jigsaw-parts-c-4167_4262_31814.html

(2) Euro industry. (2011). Retrieved from http://euro-industry.com/main.php?index=details&cat=119∏=23196850

(3)Propane cylinder. (2011). Retrieved from http://www.homedepot.com/buy/tools-hardware-power-tools-welding-welding-supplies-accessories-accessories/worthington-pro-grade-14-1-oz-propane-cylinder-179413.html

(4)Black & decker js660 jig saw with smart select dial. (2011). Retrieved from http://www.amazon.com/Black-Decker-JS660-Smart-Select/dp/B001JJD0Y4