The term “automation company” is a rather broad term which can apply to component hardware manufacturers, software companies, machine builders, or system integrators. Your specific need will determine which of these companies you seek out.
Automation hardware manufacturers are companies that make the controllers used to automate machines. Even here, this term is very broad as it can encompass Programmable Logic Controllers (PLCs), Programmable Automation Controllers (PACs), Human Machine Interfaces (HMI), and even the buttons used in the machines. This category covers any company that makes hardware used in automated machines intended for use in factories. Common manufacturers include Siemens, Allen-Bradley, Parker, Cognex, Phoenix Contact, Omron, and many many more.
Automation software companies make software that is used by system integrators and end users to program and interact with the hardware manufactured by the hardware companies. This is often the programming software for a specific manufacturer’s PLC but it also comprises HMI programming, OLE for process control (OPC), supervisory control applications.
Machine builders are automation companies that create machines from individual automation components. This type of automation company focuses on the mechanical aspect of creating a machine to perform a specific task. It is relatively common for these companies to have some software engineering staff on hand to program the machines for most tasks.
System integrators handle more complex automation tasks that are often beyond the scope of a single machine or require more complex development that the typical machine builder handles. This type of automation company has a very broad level of experience with different types of hardware and is often tasked with integrating systems from different machine builders. System integrators also implement supervisory control systems for data mining and dashboarding.