Manipulator with internal and external handles: One system for different component geometries
A manipulator with internal and external grips picks up components from either the outside or the inside, depending on which gripping direction the component geometry allows. Zeilhofer Handling Technology develops these manipulators individually for components with a wide variety of geometries, from aerospace and mechanical engineering to general industrial manufacturing.
What looks similar at first glance often differs considerably in practice, especially in whether a component offers a stable outer contour for clamping or whether access is only possible from the inside. If each access direction requires a separate fixture, unnecessary setup times, additional investments, and more storage space for interchangeable fixtures result.
The answer is a manipulator with interchangeable gripping jaws for internal and external gripping. A comparable approach for components with particularly complex geometries is described in the article "Individual Grippers and Fixtures: Custom Construction for Every Geometry" .
Why the choice of gripping direction often fails in practice
Components differ in weight, shape, and surface finish, but above all in how securely they can be gripped. This is precisely where the real challenge often lies in practice: some components lack a stable, undamaged gripping point on their outer edge, for example, because the surface is delicate or the contour too irregular. Others, on the other hand, can only be gripped from the outside because there is no access to the interior.
Maintaining a separate holder for each access direction is time-consuming, ties up storage space, and increases investment costs. A related problem with frequently changing components is also described in the article " Manipulator with interchangeable gripper system for flexible production processes ".
One system, two gripping directions: Interchangeable jaws instead of two devices
The core of the solution consists of interchangeable jaws on the articulated arm manipulator . Depending on the component, the appropriate jaw variant is used, either for external or internal gripping, for example via a bore, a recess, or an inner rim.
Instead of maintaining two separate handling devices or undertaking complex modifications, simply changing the gripping jaws is sufficient. This saves setup time and increases flexibility in daily production, especially for components with significantly different accessibility. The gripping jaws are among the fixtures that we individually design as part of the overall system; you can find more information on the page Fixtures, Grippers, Suction Cups & Magnets .
This is how switching between the inside and outside handles works.
Changing the jaws follows a fixed procedure and usually requires no additional tools:
Place the component and move the manipulator into the changeover position.
Release the locking mechanism of the current jaws
Remove the jaws and attach suitable jaws for the new gripping direction.
Close the lock and perform a function test.
Pick up the next component and continue working.
This reduces a setup process, which would traditionally have meant several minutes of downtime, to a quick adjustment during operation.
Secure gripping for a wide variety of components
Whether gripping from the inside or outside doesn't change the fundamental requirement: the component must be securely fixed and guided in a controlled manner. The manipulator supports virtually the entire weight of the component, allowing even bulky or heavy parts to be positioned precisely with minimal effort. This reduces physical strain on workers and noticeably lowers the risk of accidents.
Our articulated manipulators can handle loads up to 800 kg, and the ZH90 lifting axis even up to 1,200 kg, both with pendulum-free guidance. The article "Manipulator, Crane, or Chain Hoist: Which is for What? " describes the general advantages of a manipulator over a crane or chain hoist.
Interchangeable jaws compared to other solutions
When accessing different components, three basic approaches can be distinguished, with noticeable differences in effort and flexibility:
One fixed device per gripping direction: very quick changeover, but high investment and storage costs, as a separate system is required for both inside and outside gripping.
Modification of the existing equipment: lower investment, but long setup times, tool usage and system downtime with each change
Interchangeable jaws: one basic device for both gripping directions, changeover in minutes without special tools, low investment with high flexibility
Custom-designed for your components
Each component has its own requirements regarding weight, shape, and accessibility. Therefore, we design each mounting individually. The planning process takes into account, among other things:
Component weight
Dimensions and geometry
Gripping options from inside and/or outside
Surface finish
focus
required freedom of movement
Requirements of the production process
Based on this, a customized recording is created that can be optimally integrated into the existing production process.
Less downtime, more process reliability
Because internal and external gripping can be performed on the same manipulator, switching to a second device and the associated downtime are eliminated. This directly impacts system availability: less downtime, a more consistent material flow, and noticeably shorter setup times, especially when the order sequence changes frequently. A similar principle for components with particularly complex geometries is also described in the article "Manipulator with Interchangeable Spreading Mandrel" .
Typical areas of application
aviation
automotive industry
Mechanical engineering
Medical technology
Precision engineering
general industrial manufacturing with a high variety of components
Interchangeable jaws ensure maximum flexibility wherever components need to be gripped from both the inside and the outside.
From consultation to commissioning
Consultation: We review your component range and clarify which components can be accessed from the outside and which can only be accessed from the inside.
Concept: You will receive a design proposal for the manipulator, clamping jaws and control system, including an initial price indication.
Manufacturing: Design and construction in our plant in Holzkirchen, with our own technicians, certified according to ISO 9001 and TISAX Level 2
Commissioning: Assembly, training and commissioning directly at your site, worldwide, with optional maintenance contract
One solution, many access directions
No two components are alike, and often accessibility is the deciding factor in whether gripping must be done from the inside or the outside. Instead of maintaining a separate system for each variant, interchangeable gripping jaws combine both gripping directions in a single manipulator. This creates a solution that adapts to the component, not the other way around.
Frequently asked questions about the manipulator with internal and external handle
What is a manipulator with an internal and external handle?
A manipulator with internal and external grips has interchangeable gripping jaws, allowing components to be securely gripped either from the inside or the outside, depending on their geometry.
For which components is an inside or outside handle suitable?
An external handle is suitable for components with a stable, undamaged outer contour. An internal handle is used when the outer surface is delicate, does not offer a secure clamping point, or the component has a hole, recess, or inner edge.
How quickly can you switch between the inside and outside handles?
In most cases, a single movement is sufficient, without any special tools. The exact time required for the change depends on the chosen locking mechanism and the individual design of the mount.
What advantages do interchangeable jaws offer compared to two separate devices?
Changing the jaws costs significantly less than operating two separate systems. You save on double the investment, require less floor space, and can get through your daily production without lengthy setup times.
Is it possible to retrofit an existing manipulator with an internal and external handle?
Often yes, provided the existing recording interface allows it. The best approach is for us to take a close look at your existing system and tell you what is technically possible.
Up to what weight can components be handled?
Our articulated manipulators can handle components up to 800 kg, while the ZH90 lifting axis can handle up to 1,200 kg. Both guide the load without pendulum movement; the specific design depends on the weight, geometry, and gripping direction of the respective component.
For which industries is this solution suitable?
Industries that benefit the most are those with a high diversity of components and different access requirements, such as aviation, automotive, mechanical engineering, medical technology and other industrial manufacturing.
Further topics from the blog and guide
Guide: Manipulator, crane or chain hoist: Which one is for what?
Manipulator with interchangeable gripper system for flexible production processes
Custom grippers and fixtures: Special construction for every geometry
Manipulator with interchangeable spreading mandrel: One system for all roller diameters
How do you want to handle your components flexibly and safely?
Do you have components with varying gripping requirements and are looking for a fixture that covers both internal and external gripping? Our engineers will be happy to advise you and design a customized solution for you, Made in Germany, from a single source.
Our guide, "What is a manipulator?", offers more in-depth information on manipulators, their variations, and selection criteria.
