Bhoma is not Bhima.
Briefly, from my "Interpretation " article:-
"The Bhoma, sometimes called Kala, is a representation of the son of Wisnu and Basundari, and thus is the child of water and earth. The joining of water and earth results in the growth of plants, which in a society dependent upon agriculture equates to prosperity. In Sanscrit, Bhoma means "born of the earth". Thus Bhoma can be taken to represent the growth of vegetation.
When Bhoma appears in the base of the keris blade this is a reinforcement of the Mt. Meru representation, as the lower slopes of Mt. Meru are covered in foliage, and this is the abode of Bhoma.
But Javanese symbolism is very often polysymbolism, and the nature of Bhoma is as a protective element, so the inclusion of Bhoma in keris iconography also provides protection from evil."
This links to the complete article.
http://www.kerisattosanaji.com/INTERPRETATIONPAGE1.html
The image of Bhoma that I have posted here is only one way in which he can be represented. Other human-like figures can be found on keris blades. The puthut is fairly common, this is a figure in a meditating position.
We can find a lot of different figures associated with the keris, and they were all put there for a reason, but sometimes that reason is not always obvious, this is one of the reasons why it is necessary to move beyond simply trying to study keris and direct our study at the entire culture and society. The keris is only one blossom of an entire culture. It is absolutely impossible to understand anything at all about the keris unless we first gain at the very least a basic understanding of the culture which gave it birth.