Perfect Drive, Every Time Canon’s Precision Cartridge System That Optimises Drive Transmission in Laser Printers

Canon has filed a patent for an improved cartridge mounting system for image forming apparatus – printers, copiers and multifunction devices – that refines the way drive force is transmitted from the printer’s main assembly to the replaceable cartridge. The invention introduces a cartridge-side pushing member that actively adjusts the inclination angle of the drive output member during engagement, ensuring smoother and more precise power transmission every time a cartridge is inserted.

The Problem

Laser printers and copiers rely on replaceable cartridges – typically toner cartridges or process cartridges – that contain the photosensitive drum, toner and other components needed to produce printed pages. When a cartridge is inserted into the printer’s main assembly, a mechanical coupling must engage between the printer’s drive motor system and the cartridge’s drum and other rotating components. This coupling must be reliable, engage smoothly and transmit rotational force accurately for the life of the cartridge.

A common approach to this coupling involves a drive output member in the main assembly that engages with a receiving element in the cartridge. For this engagement to work well, the drive output member must be correctly aligned with its counterpart in the cartridge. If the drive output member is at the wrong inclination angle at the moment of engagement, the coupling may be imprecise, cause wear on the coupling components, generate noise or result in inconsistent image quality.

Conventional systems use a main-assembly-side pushing member to set the inclination of the drive output member. However, the interaction between this pushing member and the drive output member can be further optimised if the cartridge itself also participates in positioning the drive output member at the correct angle during the coupling process.

What This Invention Does

Canon’s invention adds a cartridge-side pushing member to the cartridge. This element works in coordination with the main-assembly-side pushing member – the component in the printer body that already pushes the drive output member to set its inclination. By also incorporating a pushing member in the cartridge, the system gains additional control over the inclination angle of the drive output member during coupling.

Specifically, the cartridge-side pushing member is configured such that its interaction with the main-assembly-side pushing member changes the inclination angle of the drive output member – in a controlled, purposeful way. This bidirectional positioning approach enables the drive coupling to achieve a more precisely controlled alignment state, improving the quality and consistency of drive transmission from the main assembly to the cartridge.

The result is an image forming system where the cartridge actively participates in achieving optimal drive coupling geometry – rather than simply receiving whatever coupling position the main assembly presents.

Key Features

Cartridge-side pushing member. A dedicated pushing element in the cartridge actively participates in positioning the drive output member, complementing the main-assembly-side pushing member to achieve more precise coupling alignment.

Bidirectional inclination control. By having both the main assembly and the cartridge contribute to setting the drive output member’s inclination angle, the system achieves a controlled equilibrium position optimised for reliable drive transmission.

Photosensitive drum coupling. The cartridge includes a photosensitive drum – the core image-forming component – ensuring that the precise drive transmission enabled by this system translates directly to improved image quality and consistency.

Detachable cartridge architecture. The cartridge is detachably mountable to the main assembly, maintaining the user-replaceable cartridge design that is central to Canon’s product line while improving the drive coupling system.

Compatibility with existing drive architecture. The system builds on the existing main-assembly-side pushing member infrastructure, adding the cartridge-side element as an enhancement rather than requiring a complete redesign of the drive system.

Who Is Behind It?

Canon Kabushiki Kaisha is one of the world’s largest imaging technology companies, with a dominant position in the laser printing, copier and multifunction device market. The inventors are Shigemi Kamoshida, Isao Koishi, Goshi Ozaki, Tetsuo Uesugi, Noriyuki Komatsu and Yukio Kubo. This application is a divisional of AU 2024200755. The application is managed by Spruson & Ferguson in Sydney.

Why It Matters

Print quality consistency and cartridge reliability are among the most commercially sensitive aspects of the laser printer market. Customers judge printer performance by the consistency of output across millions of pages and the smoothness of the cartridge replacement experience. Drive coupling failures or misalignments that cause image quality defects – banding, uneven density, drum-related artefacts – are a significant source of customer dissatisfaction and warranty claims.

Canon’s ongoing investment in cartridge drive system patents reflects the importance the company places on engineering excellence in the mechanical interface between printer and cartridge – an area where marginal improvements in reliability and image quality have significant commercial implications. With IPC classifications covering rotational couplings (F16D 3/04, F16D 1/112) and electrophotographic apparatus (G03G 15/00, G03G 15/08, G03G 21/16, G03G 21/18), the patent spans the mechanical and electrophotographic engineering at the heart of Canon’s printing technology.

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AU 2026201557 was published in the Australian Official Journal of Patents on 19 March 2026 and is open for public inspection. Patent applications represent inventions that are sought to be protected and do not necessarily reflect commercially available products.