IP-2023-000104 - [2024] EWHC 233 (IPEC)

The invention in the Patent is entitled “Method and system for calculating and reporting slump in delivery vehicles”. The vehicles in question are concrete mixing trucks. “Slump” is a characteristic of concrete mix; the greater the slump, the more fluid is the mix. When the mix is delivered by the vehicle to the site where the concrete is to be used, its slump must be within the tolerance required, i.e. fluid enough to be workable but not too fluid such that the concrete will not dry in a satisfactory way.

The Patent explains that it was part of the prior art to install in the vehicle a means to measure slump. The slump of the mix is related to the driving force required to rotate the barrel on the vehicle containing the mix. Thus, measuring the torque required to rotate the barrel permits measurement of the slump. If the slump is too low, water can be added at the site to achieve the correct level. If the slump is too high, the Patent states, the truck has to return to the depot in order to add particulate concrete ingredients to fix the problem. Information taken from sensors measuring the torque loading on the barrel can be stored. Later retrieval and use with other such data permits better measurement of the slump.

The specification identifies the invention claimed as an improved means for calculating and reporting slump. The specification then explains the invention by quoting claim 1. This is claim 1 as divided by CCL into integers, along with integer numbers, but here omitting the reference numbers contained in the claim:

“[A] A system for calculating and reporting slump in a concrete delivery truck having a concrete mixing drum and hydraulic drive for rotating the mixing drum, the system comprising:

[B] a rotational sensor mounted to the mixing drum and configured to sense a rotational speed of the mixing drum,

[C] a hydraulic sensor coupled to the hydraulic drive and configured to sense a hydraulic pressure required to turn the mixing drum, and a processor computing a slump value using the sensed hydraulic pressure required to turn the mixing drum from the hydraulic sensor,

characterised in that the processor is operative to:

[D] (i) compare current pressure and speed measurements to previously stored pressure and speed measurements,

[D] (ii) determine if the speed and pressure are stable,

[D] (iii) erase the stored pressure and speed measurements if the speed and pressure measurements are not stable,

[D] (iv) store the current pressure and speed measurements,

[E] continue said steps (i) to (iv) until pressure and speed measurements have been stored for a full drum rotation, and then calculate a current slump value using the stored pressure and speed measurements.”

The Patent expires in February 2025.