Group 22 - Swingline Electric Stapler
Purpose of Product
The purpose of the Swingline Electric Stapler is to provide a way for a user to bind papers together with a staple without requiring any force to be applied by the user.
How it works
When paper is put into the stapler, it presses on a trigger. When the trigger is activated, the stapler arm is pressed down and a staple is driven through the papers. A metal plate under the papers bends the staple to prevent it from unintentionally coming off.
Types of Energy Used
The stapler converts electrical energy (in the form of DC current from a battery or converted from AC current from a wall outlet) to mechanical energy that is used to force the staple through the paper.
Before disassembly, staples were put into the staple tray, and the product was tested. The product ran as expected, stapling a small stack of papers together without problems. As it operated, a blue LED light flashed at the base of the stapler. The plastic casing didn't move at all during operation, just the metal stapler arm. A low noise could be heard, probably coming from motors and gears operating.
Before disassembly, we expected to find about sixty components in total in the stapler. We felt this was a reasonable number because we expected there would be many small parts needed inside the stapler. We expected to find five different materials used to make the various components, with most of the parts being plastic or a type of metal.
All steps easy unless otherwise noted.
Screwdriver used is regular Phillips screwdriver unless noted. Used to remove all screws.
If no tool mentioned, operation done with hands.
- Staple remover was removed by pressing on indentation with the symbol and pulling towards the back of the stapler
- Black casing was removed by pinching at the front and sliding towards the back of the stapler (to completely remove, move to the back as far as it easily goes, then pinch the front of the piece and pull firmly until it comes off)
- Sticker showing battery positioning was cut with a slot screwdriver
- Stapler was turned over, and the black padding and white “Swingline” sticker were peeled off
- Two screws on left hand side of casing was removed with screwdriver
- Six screws on bottom of casing were removed wish screwdriver
- Blue staple depth tabs were removed by pulling off
- Casing was removed by carefully pulling each half (left and right) in opposite directions. Pulled until completely separated, but some slack still in wires
- Battery contacts removed by sliding out of their slots
- Screws holding circuit on left side of casing removed with screwdriver
- Blue manual-auto switch pulled out
- Manual trigger removed by pulling off support pegs (Needed slot screwdriver to pry trigger off of supports)
- Casings completely removed and set aside
- LED bulb removed
- Two screws holding metal gear frame to bottom casing on left side removed with screwdriver
- Two screws holding metal gear frame to bottom casing on bottom removed with screwdriver
- Bottom casing removed and set aside
- Black-and-red and red-and-white-and-black wires running from bottom casing disconnected from circuit board
- Black-and-red wires running from lower front of stapler removed
- Main circuit board screw removed
NOTE: single black wire pulled out of socket during next step, making complete reassembly impossible
- Circuit board removed and wrapped around toward back of stapler
- Screws holding metal gear casing and plastic gear casing removed
- Slot screwdriver used to bend lock washer until it could be removed from the last gear shaft
- Plastic and metal casings separated
- Shaft at back and spring coil removed
- Gear casing separated from staple slide
- Screws holding plastic and metal bottom casings removed, and pieces separated
|Part #||Part Name||Quantity||Material and Reason for Choice of Material||Manufacturing Process||Image||CAD Crawings|
|1||Spring||1||Steel, needs to be sturdy, but compressible||Machined|
|5||Casing||4||ABS Plastic||Injection Molded|
|7||Battery Contacts||2||ABS Plastic, Steel||Injection Molded, Cut|
|8||LED Light||1||ABS Plastic||Injection Molded|
|9||Manual Start Button||1||Plastic||Injection Molded|
|10||Staple Remover||1||Plastic, Steel||Injection Molded, Machined|
|13||Fame for Gears||1||Steel||Machined|
|17||Drive Shaft Housing||1||Steel||Metal Casting|
|19||Drive Spacer||1||Plastic||Injection Molding|
|22||Frame for Button||1||Steel||Metal Casting|
|23||Circuit Board||1||Silicon, Plastic||Manufactured|
|26||Plastic Display||1||ABS Plastic||Injection Molding|
|27||Small Circuit Board||1||Plastic, Silicon||Manufactured|
|28||Plastic Slide||1||ABS Plastic||Injection Molding|
|29||Plastic Housing||1||ABS Plastic||Injection Molding|
|31||Plastic Ends||1||ABS Plastic||Injection Molding|
|34||Small Plastic Housing||1||Plastic||Injection Molding|
We suggest the following changes be made to the product:
- Make wires more secure
We felt the inside workings of the stapler were too delicate. Many of the wires running from the main circuit board to the various parts of the stapler were not attached securely enough. The wires were very thin and could easily be cut or pulled out of their connections if not handled with extreme care. If heavier adhesives or thicker wires were used, this would be less of a problem.
- Change staple tray
The staple tray is easily jammed. It is supported on two rails, one on each side of the tray. When the button is pressed to eject the tray so staples can be loaded, the tray usually gets caught up on its rails. The user then needs to pull on the tray to create enough clearance to load the staples into the tray, and the force needed is usually significant. We suggest polishing the rails and the tray, or using a lubricant, in order to decrease the friction between the rails and the tray and prevent the jamming. The rails and the tray could be manufactured so that the fit between them is more exact, which could also help prevent jamming. If the fit is too loose, there could be too much play between the parts, allowing them to jam, which seems to be the case now. If the fit is too tight, however, the friction between the parts increases, which could also cause it to jam.
- Increase clearance where paper is inserted
Due to the rigidity of the stapler's casing, there is little clearance where the paper is inserted. This prevents the user from stapling large documents. Increasing this clearance would allow more papers to be stapled at once, although it would increase the overall size of the stapler. Also, a stronger motor or different gear ratios might be needed to ensure the stapler has the power to force the staple through a thicker stack of papers.