XNUMX. XNUMX.Search background

　Electrically assisted bicycles in Japan have become popular since they are city cycles (commonly known as mamachari) with an electric assist unit added. The reason for this is that in 2009, it became legal for bicycles to carry three people as long as they met the standards for two-seater bicycles, making it convenient for children to pick up and drop off their bicycles (less pedaling force required). Bicycles became popular. (If two children were carried, the weight would be over 30 kg, making it unstable to drive by hand, so electric power to assist the pedal force was required.) In addition, in the world (especially Europe), emphasis is placed on sportiness. The spread of electrically assisted bicycles is accelerating. As described above, demand for electrically assisted bicycles is showing signs of increasing demand both in Japan and abroad. In the future, it is likely that most bicycles will be equipped with electric assist, and further development of electric drive units will be required. Therefore, we will analyze the status of patent applications focusing on drive units, which are the main parts of electrically assisted bicycles, and predict future trends in electrically assisted bicycles.

*The production number of electrically assisted bicycles in Japan from 2015 to 2022 has fluctuated from approximately 20 to 33 units. (From the Bicycle Association, General Incorporated Association)　

XNUMX. XNUMX.Technical overview

　There are slight differences in standards for electric assist bicycles depending on the country. In particular, Japanese electrically assisted bicycles must control the assist force so that it reaches zero at 24km/h. On this point, in Europe, there is no need to control the assist force, only the maximum assist speed and maximum output of the motor are regulated. Because of these regulatory differences, electric bicycles made in China, which do not require control functions, are gaining market share in Europe. However, in recent years, attention has been focused on sports-oriented (health-oriented) bicycles that can control pedal force assist, and demand for electric bicycles equipped with drive units that can control the appropriate amount of assist force is increasing.

XNUMX. XNUMX.Search strategy (overview)

　In this search, a patent population was created under the following search strategy.

・First, we focused on Japan in order to understand the trends of domestic manufacturers.
・Applicable to applications filed after January 10, 2015, which is the most recent 1 years. (Because it is on the rise)
・Create a group of drive units for electrically assisted bicycles.
└ Bicycles equipped with electric motors B62M6/40, B62M6/80 IPC (FI) classification code,
　The scope of application is IPC (FI): B60L15/00, which broadly covers electrically assisted bicycles, and F term: 5H125, which is given from the technical perspective of "electrically assisted bicycles", was used.

Applying the above IPC and F-term classification codes, search operations were performed, and 1167 items were set as a population.

<Patent classification>
・ B62M6/40 ・Passenger-propelled bicycle with auxiliary electric motor [2010.01]
・ 5H125AA18 Electrically assisted bicycle (one that assists human power)
(Compatible IPC (FI): B60L15/00 Control means for driving electric propulsion vehicles at a specified speed, e.g. traction motor speed)

4. Application trends (analyzing the determined population)

-Application trends in Japan
　The number of patent applications related to drive units for electrically assisted bicycles is 955/1167 (excluding those that are powered by engines in the abstract). As a result, the number of applications has been on the rise since 2015, and in 2018, the number of applications increased rapidly, reaching 195 applications. In recent years, there has been a trend of increasing demand worldwide, so it appears that efforts are being put into development. Future trends in applications will be closely watched.

*1) Undetermined: Since it will not be published until one year and six months have passed since the application, the application year that includes unpublished gazettes at the time of the search is treated as the undetermined year.

　Prior to the search, it was thought that the ranking of top applicants would be dominated by Panasonic and Yamaha, but it was unexpected that Shimano surpassed Panasonic to take first place. Additionally, Taiyo Yuden, a manufacturer of electronic parts (inductors, etc.), came in 4th place, and was confirmed to be developing products related to bicycle electric units (motor parts).

・Application trends and number of applications of the top 7 applicants

　Shimano has seen a sharp increase in the number of applications since 201. Currently, 2018 applications have been filed in 99, with the largest number of applications related to drive units for electric bicycles, but the number of applications has been on the decline since 2019.
　Furthermore, although the number of applications for Panasonic, Yamaha, and Honda Motor Co., Ltd. has fluctuated slightly, they peaked in 2018-2019 and have been on the decline in recent years. It is assumed that the process is moving from development to manufacturing. Taiyo Yuden had maintained the number of applications at around 2019 until 10, but since 2020, the number of applications has decreased, but development has continued.

XNUMX. search result

　Panasonic and Yamaha, which are the top manufacturers in filing applications, have confirmed that Shimano has become the number one company in terms of number of applications since 2017 and is maintaining its number one position. Shimano is a world-famous bicycle parts manufacturer, and in recent years they have been focusing on the development of electric drive units, and it can be seen that they are working on this as one of Shimano's main products. In addition, bicycle parts other than electric drive units are being sold around the world, and many bicycle manufacturers (finished bicycle products) in Europe, Taiwan, the United States, etc. are using Shimano, so electric drive units are now being sold around the world. I can tell (from general information). Panasonic has mostly sold electrically assisted bicycles mainly for domestic demand, but since around 2017, he has started producing electrically assisted bicycles (completed products) for sports purposes. There were multiple applications for. Additionally, it has been reported that Yamaha's sports electric drive units have been shipping since around 2015 and are currently showing their presence in Europe.

　As mentioned above, the number of patents related to electric bicycle drive units was dominated by the two main filing manufacturers, but it appears that Shimano has newly entered the development of electric bicycle drive units, leading to a development competition among the three manufacturers. In Europe, electric drive units from Bosch and Yamaha are widely used, and it will be interesting to see how Shimano, as a long-established manufacturer of bicycle parts, will develop drive units for electric bicycles. Additionally, Yamaha and Panasonic will also be focusing on trends in their efforts to expand. We are also seeing new manufacturers (start-ups, Chinese) enter the market, so we must keep an eye on trends in the development of electric drive units for bicycles. Furthermore, why is Honda Motor Co. included if it does not develop drive units (mechanisms) for electrically assisted bicycles? There are many applications related to control systems for drive units (including electric bikes), and these include patents related to control systems for electric bicycle drive units, so they were included in the population of this study.　
*Explained in trend reports of major companies.

5.1 Shimano’s trends

　Electrically assisted bicycles developed by Shimano around 2010 mainly had an electric drive unit with a motor built into the hub (front wheel). This configuration had an electric motor attached to the front wheel hub to control vehicle speed and motor output.
　The one that was filed in 2018 moves the electric assist unit to the crank and has a larger number of sensors, controlling the assist force by sensing the human load applied to the pedals.

references:JP 2020-1578
　The present application is a single-axis type drive mechanism, and has specifications that allow detailed assist control using various sensors. Additionally, since it is a single-shaft drive mechanism, it has the characteristic of direct assist output, which is preferred in Europe and other countries.
*Applications have also been filed in Germany, which suggests that Shimano is gradually focusing on electric parts by leveraging its parts brand power.

　Additionally, it has been reported that the company is selling assist unit components (see the image below) worldwide under the name "SHIMANO STEPS."
*Uses a single-axis drive unit mechanism.

　Shimano has recently applied for a technology that mechanically learns and controls data obtained from a large number of sensor information (JP 2020-6834,JP 2023-151357 etc.), it is predicted that in the future, control of electric parts including electric assist units will be commercialized that incorporates AI/ML.

5.2 Panasonic’s trends

　Panasonic is already known to be a Japanese manufacturer of electrically assisted bicycles since before 2010.
　Panasonic's electric assist drive mechanism around 2010 has a drive unit configuration that includes a pedal crankshaft, but it is composed of two axes: a human power axis for pedaling, and an axis for generating torque (an electric motor) for assisting. The main thing was that However, in recent years (2018), drive units that have been applied for have developed units that can be used in two configurations, single-shaft and dual-shaft, and units that are only single-shaft or dual-shaft. It appears that they are developing a variety of drive units with two specifications: one that provides direct assist torque with a single-shaft type, and one that provides mild assist torque with a two-shaft type. As for future control technology, there are currently no efforts to use AI/ML to control the drive unit, but Panasonic's AI/ML technology has already been adopted in other products and is necessary. It is thought that the development will be rapid if a gender emerges. The current latest model (2024) is a power-assisted bicycle that is easy to use, compact, easy to carry (carrying children), and suitable for commuting to school and for the elderly. The company also sells e-BAKE ``XEALT,'' which emphasizes sportiness.

　Panasonic's basic drive unit configuration. Initially, the drive unit configuration for electrically assisted bicycles. *Patent 4906982[Figure 2] See

　Further, this figure is a sectional view of a drive unit having a uniaxial configuration. A drive unit that can be used in both a single-axis configuration and a two-axis configuration. This configuration has been filed for a structure (Fig. 7) that is mainly a two-axis configuration, but a modified example is the configuration shown in (Fig. XNUMX).
references:JP 2020-79016
(The configuration of Figure 2 is JP 2023-49765also adopted)

5.3 Trends at Yamaha Motor

　Like Panasonic, Yamaha Motor is a major domestic manufacturer that develops electrically assisted bicycles, and was the first company in Japan to develop and sell electrically assisted bicycles. It is famous that it was sold under the name "PAS" at the time (1993). After that, we tried to expand into Europe, but when it was first sold in Europe, electrically assisted bicycles did not require manual assistance, but instead were accepted as ones that could simply control the vehicle speed and power (they could also be self-propelled). However, as the Japanese-style electric assist control was not popular, sales were sluggish and the company had to reconsider its strategy. In 2014, we developed a drive unit that improved on the previous problem (reviewed the control method of the electric assist mechanism) and expanded it to Europe again. The drive unit has been developed and commercialized for Japan and Europe, and it is reported that in 2019, the cumulative production of drive units reached 500 million units.
　Based on the application status, Yamaha Motor's drive unit is being developed in two configurations: a single-shaft type and a two-shaft type.The single-shaft type is easy to output a direct feeling, and the two-shaft type is good at mild output. It has been confirmed that the development of an electrically assisted bicycle that takes advantage of the characteristics of

references:JP 2019-147528
　It has a two-axis configuration with a pedal axis and an assist torque generating axis, and torque is detected and controlled from the pedal axis. *See Figure 1

references:JP 2019-31257
　An application has been filed for a drive unit with a single-shaft configuration in which the pedal shaft and the assist torque generation shaft share a common shaft. *See Figure 1

　In addition, in applications filed after 2022, there are many inventions related to control for efficiently supplying electric power (battery) in the configuration of the electric drive unit as described above.JP 2022-118600,JP 2023-30689 etc. can also be seen.

5.4 Trends in Honda Motor Co., Ltd.

　It was in March 2023 that there was information that Honda Motor Co., Ltd. was entering the electrically assisted bicycle market. What was announced was "SmaChari", which is related to the control of electrically assisted bicycles. The control-related invention is a method for controlling a motor drive force according to a pedal force estimated by a calculation unit that estimates the pedal force, without complicating the structure for detecting the pedal force or requiring modification of the bicycle. It is something to control. References:JP 2020-124945

　Figure 100 shows the configuration of the electric assist. In FIG. XNUMX, a control unit XNUMX controls the drive of a motor based on what is detected by various sensors. It appears that this type of control linked to a smartphone app has been commercialized as ``SmaChari.''

5.5 Nidek trends

　Nidek's company name was changed from the company name of Nidec to "Nidek" in 2023. The patent in 2023 is registered under the old company name.
　Nidek is developing brushless DC motors and anticipates demand for motors used in electrically assisted bicycles.
　The electric vehicle 100 is an electrically assisted bicycle that assists the user's pedaling force, and the drive device 10 is configured with a power transmission mechanism 103 to form a drive mechanism for an electrically assisted bicycle.

references:JP 2022-121335
　FIG. 100 An electric vehicle 101 includes a vehicle body 102, two wheels 103, a power transmission mechanism 10, a drive device 104, and a power supply section XNUMX. FIG. XNUMX is a perspective view of the inside of the drive device.

5.6 Bosch trends

　Bosch produces electric drive units for sports electric assist bicycles. In recent years, the company has been focusing on providing drive units for electrically assisted bicycles, ``Bosch eBike Systems.'' The technology applied in Japan includes a method of operating an electrically assisted bicycle that can be driven by muscle strength and additionally motor power, an assist force from the motor drive unit, and a method for handling obstacles in an obstacle course according to the obstacles. However, assist control is performed to overcome this problem more easily and reliably than in the conventional case. In this way, we are focusing on the development of an electrically assisted drive unit that allows for detailed control of assist force.
references:JP 2023-81345

5.7 ZF trends

　It is a manufacturer of automobile parts, and manufactures drive units (for vehicles) that are compatible with electrification. During this research, we found a patent related to a bicycle drive unit that was filed by ZF, so we would like to introduce it here.
references:Special table 2023-519268

``Drive unit (10) for a human-powered vehicle, in particular for a bicycle or EPAC, comprising a bottom bracket shaft (14), an electric auxiliary drive (16) and an output shaft designed as a hollow shaft. (22) are arranged coaxially with each other.”

XNUMX.Summary

　A trend analysis of patent applications has confirmed that motor control for electrically assisted bicycles is evolving year by year.
　In the future, there will be a need for control that can be applied to a wider range of human power.
　The technology for processing data detected by sensors incorporates AI/ML technology to perform human-friendly control (e.g., responding to pedal force, responding to the surrounding environment, complying with laws and regulations), and requires optimal assist control in response to constantly changing conditions. It is expected that (As of 2023, some bicycle manufacturers have already adopted it, but it is not enough)

Investigation Part 1 Iwata