Dirt Collecting Floor Mat Apparatus

This invention relates to a floor mat apparatus for installing at the entrance to an area which is required to be kept free of dirt or bacteria, the floor mat apparatus serving to collect dirt or bacteria from the footwear of people walking through the entrance or from the wheels of trolleys passing through the entrance.

It is known from British patent specification No. 1 475 366 to form a floor mat from PVC having a high content of plasticizer so that the surface of the mat is tacky and the dirt or bacteria on peoples' shoes or on trolley wheels will adhere to the surface of the mat. Such mats are laid on the floor at the entrance to the area which is to be kept free of dirt or bacteria, for example in a hospital, or in a semiconductor or pharmaceutical plant. It is necessary to clean the mats relatively frequently in order to maintain the dirt and bacteria absorbing properties. This cleaning is carried out using water to which a detergent has been added. Unfortunately, if the mats are cleaned when in position at the entrance where they are placed for use, the cleaning water washes under the mats and consequently the mats become very slippery and therefore dangerous. It is virtually impossible to clean the mats on the floor without incurring this problem, unless perhaps extreme precautions are taken, which precautions are time consuming and involve restricting the normal passage of people and increasing the number of cleaning personnel required. Alternatively, the mats may be removed to some other area for cleaning and drying. However, the mats are very heavy and therefore difficult to handle easily and this procedure necessitates several sets of the costly mats, one set laid down in use, a second set cleaned ready to replace the one set, and a third set being cleaned and dried.

The present invention provides a floor mat apparatus comprising a length of mat material having a tacky surface for collecting dirt and/or bacteria, means for supporting the mat over an area across which personnel pass, means for moving the mat across said area so that a fresh portion of the mat is moved into said area and a used portion of the mat is moved out of said area, and means for cleaning the used portion after being moved out of said area.

Embodiments of this invention will now be described, by way of examples only, with reference to the accompanying drawings, in which:

FIG. 1 is a diagrammatic longitudinal section through a floor mat apparatus;

FIG. 2 is a similar section through a second apparatus;

FIG. 3 is a similar section through a third apparatus.

FIG. 4 is a similar section through a fourth apparatus; and

FIG. 5 is a plan view of one form of mat belt.

Referring to FIG. 1, a gap is provided in the floor at the entrance to an area or room 1 which is to be kept free of dirt or bacteria. The floor area represented by this gap is provided by the floor mat apparatus 2. The gap may be formed by a recess in the floor, in which the apparatus is installed, or the apparatus may be placed on an existing floor with ramps at each end leading from the existing floor level up to the top of the apparatus. This apparatus comprises a pair of parallel, spaced rollers 3,4 about which is trained an endless steel or chain belt 5. The roller 4, remote from the "clean" area 1, is arranged to be driven by an electric motor 4a in such direction that the belt 5 moves in the direction away from the clean area 1 over its upper stretch. The mat with tacky surface is shown in the form of an endless belt 6, longer than the belt 5, and may comprise a single mat or several mats 6a joined together as shown in FIG. 5. It is suspended as shown and held by the upper stretch of the belt 5.

A cleaning bath 7, containing water with a detergent added, is positioned below and a rotating brush 8 is provided, dipping at its lower side in the water and brushing the mat at its upper side. A rubber squeegee 9 is provided to press against the mat and wipe off excess water to speed the drying. The mat hangs freely under its own weight against both the brush 8 and the squeegee 9. Instead of or in addition to the squeegee 9, an air blower 9a may be provided (FIG. 3) having a nozzle 9b directed at an angle to the belt 6 against the direction of movement of belt 6.

In use, the roller 4 is driven by its electric motor to move the belt 5 and hence the belt 6, so that the tacky mat moves in the direction of the arrow. This movement may be continuous or intermittent: for example, a light beam (see detector 20) interrupted by a person walking over the mat may be used to drive the electric motor (see control line 21) for some duration, either immediately or after a delay sufficient to allow the person to walk from the mat. The portion of mat leaving the area of the gap in the fixed floor passes towards the cleaning bath, where the brush 8 cleans the mat and the squeegee removes excess water. By the time this cleaning portion of the mat passes around roller 3 to come into use again, it is dried.

The rate of moving the mat across the effective floor area may be made adjustable to the actual traffic density or dust input at the particular entrance where it is installed. The cleaning of the mat is not limited to the use of the brush 8 which is shown: for example, the mat may pass directly under the surface of the water in the bath 7. The rubber squeegee may be arranged to be turned manually from time-to-time to touch the brush 8 to clean the squeegee.

The belt 6 may be made up of several pieces of mat, each for example 2 meters long. The effective area between the rollers 3,4 (which is substantially level at its opposite end with the fixed floor on either side of the apparatus) is typically 1 to 3 meters, but may be more depending upon such factors as traffic density, and dust input.

Preferably the tack mat includes a mechanical reinforcing, for example of fabric or steel mesh. This may be embedded in the mat or applied to the reverse side of the mat.

The cleaning bath may include means for filling it automatically to a predetermined level. Also, it may include filtering means for removing solids, for example, which are cleaned from the mat.

FIG. 2 shows a modified arrangement which enables a reduction in the height of the apparatus. Thus, the belts 5 and 6 are of the same length but are trained inwardly over the brush 8 and then over an intermediate roller 10.

FIG. 3 shows an apparatus for refreshing the mat with plasticizer. Thus a bath 11 of plasticizer solution is provided. Normally as shown, the belt 6 is washed by the brush 8 in bath 7, dried by blower 9a and returns in due course to the upper section for use. However, at night for example, when no traffic is passing, a control means 30 is energised to run the belt 6 for a time period with the washing brush operating, to thoroughly wash the tacky belt. Then rollers 12 are lifted mechanically by the control means so that the belt 6 is no longer in contact with the washing brush 8 but the belt drive is continued for a time period to effect thorough drying. Then rollers 13 are mechanically lowered by the control means so that the belt passes through the plasticiser solution to regenerate the tacky material. Finally, rollers 13 are lifted and the belt is driven for a time period to dry the belt 6. The apparatus is thus fully reconditioned ready for use in the morning.

FIG. 4 shows an apparatus similar to that shown in FIG. 1, and includes a system for replenishing plasticizer material to the mat. This system includes plasticizer applicator means 40 operable to displace the rollers 13 to deflect the mat 6 into contact with the plasticizer material contained within the plasticizer bath 11 in a manner similar to that described with regard to FIG. 3.

It will be noted that these apparatus provide automatic cleaning of the mat, avoiding the problems of slippery mats and minimizing the requirement for cleaning personnel.

Any one of numerous appropriate chemical formulations may be employed for the synthetic plastic mat with tacky surface. One possible example comprises 40 parts polyvinyl chloride (PVC), 58 parts dibutyl phthalate and 2 parts barium cadmium as stabilizer. Another example comprises 40 parts PVC and 60 parts di-(2-ethylhexyl) phthalate. Another possible example comprises 45 parts PVC, 55 parts dioctyl phathalate and 1 part barium cadmium stabilizer. In the above examples, all proportions are given in parts by weight. Endless variations are possible for maximum tackiness, migration rate, etc.