Precision Telescopic Slides

Overview

This guide covers the function, assembly, and use of Vention’s precision telescopic slide ecosystem.

Applications

These slides are typically found in machine-tending applications that require high rigidity and repeatability. Using these slides, drawers can be constructed to hold a large variety of parts.
The slides feature bi-directional opening, which is a key feature for easy loading and unloading.
For an example of a machine-tending application, see Ellison technologies industrial cart.

Technical Specifications

Load capacity (per pair)	230 kg
Open length	1364 mm
Closed length	700 mm
Positional accuracy (with indexing system)	+/-0.03 mm
Bi-directional opening	Yes

Slide Indexing system

Precision telescopic slides do not have a built-in catch to hold them open or closed. Vention offers an indexing system for this function (part number MO-LM-034-XXXX). We recommend adding at minimum a catch for the closed position, to prevent the drawer from sliding open unintentionally.

Adding indexing to your slide allows the accurate positioning of a drawer, which allows a robot to load or unload. Without these parts, a robot will be unable to pick parts out of the drawer reliably. The basic parts of this system are a Spring Plunger (MO-LM-034-0002) and Catch (MO-LM-034-0001). Below are a few ways that they can be employed. See the table below for the number of catches and plungers required to achieve a given number of indexing positions. An indexing position is any place where the drawer or slide must stay positioned.

		Catch (MO-LM-034-0001)	Spring Plunger (MO-LM-034-0002)

Number of indexing Positions	Catches (number required)	Spring plungers (number required)
1	1	1
2	1	2
3	2	2

Design Tips

Make sure you consider these factors when designing precision drawer assemblies:

• Precision telescopic slides are 45 mm wide, which reduces the drawer size by 90 mm from the width of the frame.

• Ensure the slides have room to move along their full travel distance.
• Determine the number of detent positions required for your application and add the appropriate number of catches and spring plungers (see table above).
• Design the drawer in a way that allows for slight adjustment to its width, so the drawer can be adjusted to fit the frame perfectly.

Assembling precision telescopic slides

The following steps should be considered best practice, although some assemblies may require them to be performed in a different order.

1. Assemble frame and drawer. We recommend a bottom-up approach.
2. Attach the slides to the frame side, using the spacer plates and two M8 x 30 mm flat head screw (HW-FN-015-0030). You will need to be able to move the slide through its range in order to properly access the bolt holes. Before tightening, ensure both slides are equally spaced.
3. Attach the slide to the drawer. It’s important to hold the drawer in place during this step: for small drawers, get another person to hold them in place; for larger and heavier drawers, you may have to support it with wooden blocks or other extrusion pieces.
4. Cycle the drawer through its full travel distance, paying attention to any tight spots. Tight spots occur when the drawer and frame are not parallel. To fix them, loosen either the drawer or the frame, and then re-tighten it when the drawer is in the position that was causing issues. The drawer is typically much easier to loosen, so start with it first. Repeating the loosen-cycle-tighten a few times is usually enough to ensure the drawer operates smoothly.
5. If you are using Vention indexing system, attach the catch parts in their desired locations. Leave the spring plunger (MO-LM-034-0002) loose. Move the drawer to the position that it needs to index to and fasten both the plunger and catch parts in place. Adjust the plunger depth until it is fully seated in the catch block. Finally, tighten the nuts on the plunger to lock it in place.

Problems and solutions

Problem: A small amount of play or looseness can be detected when at an indexing position. 
Solution: Check that the fasteners are tight on the catch and spring plunger. Adjust the spring plunger so it is closer to the catch.

Problem: Drawers are hard to move, make a scraping noise when moved, and/or require high force to move past the indexing position.
Solution: Adjust the spring plunger so it is further away from the catch.

Problem: Drawer is hard to open or close, or has tight spots in its travel.
Solution: Note the location of the tight spot and move the drawer to where it is tightest. Loosen the drawer in such a way that its width can change, then tighten it again, without changing its position. This should allow the drawer’s width to match the frames so it will open more smoothly.

Problem: Drawer does not open to its full specified length.
Solution: This is usually the result of misaligned telescopic slides. Use a straight edge, extrusion, or other measuring device to align the telescopic rails on both the frame and drawer.