In this article I will explain how to design of the paper shredder machine. The design process begins by calculating the power required for the cutting process. The power will be a reference in choosing the electric motor. After determining the electric motor, the following design process is the calculation of machine parts according to the concept and construction design. Base on description of the paper shredding machine, we can determine what parts of machine must be calculate dimension and strength. Therefore, part design of paper shredder machine is spur gear transmission, helical gear transmission and main shaft.
Shredder Blade Calculation
The cutting process will occur if cutting forces on each shredder blade exceeds the tear strength of the paper. Cutting forces required on each shredder blade are:
Note:
Fi = Cutting Force per Blade (Kg)
KS = Tear Strength of Paper (mN)
S = Max Paper Load (Sheet)
g = Gravity (m/s2)
Fi = Cutting Force per Blade (Kg)
KS = Tear Strength of Paper (mN)
S = Max Paper Load (Sheet)
g = Gravity (m/s2)
Tear strength of paper can be seen in the paper specification for HVS document type of paper.
The cutting force required to crush a paper is influenced by the number of blade and the number of blade cutting edge. So the cutting forces for vertical and horizontal direction can be formulated as follows:
F1 = Cutting Force for Vertical Direction (Kg)
F2 = Cutting Force for Horizontal Direction (Kg)
Fi = Cutting Force per Blade (Kg)
i = Number of Blade
k = Number of Blade Cutting Edge
Power Requirement for Paper Shredder Design
The power required to crush a paper is influenced by torque and speed of blade. Power Requirement for cutting process can be calculated by formula:
P = Power Requirement (Kw)
T = Torque (kgmm)
n = Blade speed (rpm)
Torque in the blade occurs due to cutting force in the vertical cutting direction (F1) and the the horizontal cutting direction (F2), so the total torque in the blade can be calculated by formula,
Machine Part Calculation for Paper Shredder Design
Based on the machine construction is described in the article paper shredder machine, there are some critical part must be calculated its dimensions and strength. The machine parts are main shaft, spur gear and helical gear.
Main Shaft Design
Main shaft is the supporting shaft for shredder blade. On the shaft, there is a cutting force on each shredder blade whose value according to the results of previous calculations (cutting force for each blade = Fi). The cutting forces will cause the bending load on the shaft. Main shaft also receives a torque that is distributed by the gear transmission. Therefore the main shaft receives a bending load and torque loads simultaneously. Main shaft calculation as it can use the existing formula in the article torque and bending load of shaft together. (Read more: shaft design)
Spur Gear Design
Paper shredder machine uses two pairs spur gear. The first of spur gear is used as a gear drive for the shredder blade. The spur gear serves to make the shredder blade right and left rotating at the same speed but in opposite directions. The second of spur gear is used as gear reducer which serves to reduce a rotation by gear ratio is 1/8. Its ratio is too high, so spur gear transmission system is divided into two parts, namely the first stage spur gear by gear ratio is 1/4 and the second stage spur gear by gear ratio is 1/4. Spur gear calculation for determined spur gear dimension and strength can use the existing formula in the article calculation of spur gear dimension and strength with reference to the power requirement and the speed of standard motors. (Read more: spur gear design)
Helical Gear Design
Paper shredder machine uses a helical gear as a gear reducer of the electric motor. Helical gears have the ability to withstand the radial and axial force so it is good if connected directly to the high speed motor. This machine is fitted helical gear using a ratio of 1/5. Helical gear calculation for determined helical gear dimension and strength can use the existing formula in the article calculation of helical gear dimension and strength with reference to the power requirement and the speed of standard motors. (Read more: helical gear design)
That is a description about the Design of Paper Shredder Machine. If you find misconceptions in this post, please provide the correction in the comment box.
The writer understand better the mind of people what they want to learn through their writing therefore this article is outstanding. Thanks!!!Shredder Choice
ReplyDeleteThe writer understand better the mind of people what they want to learn through their writing therefore this article is outstanding. Thanks!!! Shredder Choice
ReplyDeletehow do we design or buy Shredder Blade?
ReplyDeletethank you for your responses
Deletethe most important factor in the design of the blade is the material specification, material treatment, cutting angle, edge radius, friction etc.
on the next post I will try to explain the details of blade design
thanks
Thanks for u info
DeleteSir plzz tell the further process of design of blade
Deletecan u please tell how to design leaf shreeder machine
show is the design of blades?
ReplyDeletethank you for your responses, on the next post I will try to show the details of blade design
Deletethanks
Thank you for showing us the design process but please upload how to design the blade itself because i think that's the most important part of the shredder. Thanks in advance and more power to you sir!
Deletedesign of blades
ReplyDeleteDo you know how to make cross cut.shredder blade.design? I have contacted you in Facebook.please check your messages
ReplyDeleteThe article says that F2 is a horizontal force but in the picture it is vertical like F1. Am I wrong ? If I am , please correct me.
ReplyDeleteHello! Great article! Right what I needed to read. I'm trying to design a scrap food shredder that may have to shred some wood too. How would equation 1 change for shredding wood rather than paper? I guess I could replace the tear strength of paper (Ks) with the shear strength of wood?
ReplyDeleteThanks!
Oscar
Hi sir can i know the standard gap between collar & blade where trying to shredd plastic bag...
ReplyDeleteKemal Gunes: The article says that F2 is a horizontal force but in the picture it is vertical like F1. Am I wrong ? If I am , please correct me.
ReplyDeletei also need to know the answer. please.