GB1561781A - Dispensing containers - Google Patents

Description

(54) IMPROVEMENTS IN DISPENSING CONTAINERS (71) We, TELEHOIST LIMITED, a British Company, of Manor Road, Cheltenham, do hereby declare the invention, for which we pray that a patent may be granted to us, and the method by which it is to be performed, to be particularly described in and by the following statement:- This invention relates to dispensing containers of the kind in which a liquid, particulate or otherwise flowable material is contained for controlled dispensation therefrom. The invention has been developed in relation to grease canisters for use with lubrication equipment and results in an improved lubrication system but is not limited thereto.

According to the invention there is provided a dispensing container for grease or other flowable material to be dispensed, com- prising an outer housing in the form of a canister having an end closure plate which provides an outlet through a coupling element, an impervious flexible bag fitting in the canister and sealed at its mouth around said outlet, there being provided within the bag a fixed tubular liner which extends away from the closure plate so that as the canister is emptied the part of the bag remote from the outlet collapses into the liner.

Means are conveniently provided for enabling an operator to ascertain when the volume of flowable material remaining within the bag has reached a predetermined value which corresponds to that at which the container should be replaced by a full container. Said means may comprise transparent windows in the housing through which a visual indication of the state of fullness or otherwise of the bag can be obtained. Alternatively or additionally, a pressure-sensitive electrical switch may be fitted in the pump to actuate an indicator lamp, or a spring-loaded contact engaged by the piston may be employed, the engagement occurring when the throw of the piston increases due to lack of the flowable material in the container.

The use of a grease container according to the invention, in an installed lubrication system for commercial vehicle maintenance and other machine maintenance, introduces a number of advantages in the working of the system. Hence the invention gives rise to an improved lubrication system comprising a pump with mounting means for installation, a replaceable grease container as above defined coupled to the pump inlet.

The invention will now be described by way of example with reference to the accompanying drawings which illustrate lubricating equipment for use on commercial vehicles and other machines, which equipment includes a disposable grease container.

In the drawings: Figure 1 is a side sectional view of the lubricating equipment including the container, Figure 2 is an end view corresponding to Figure 1, Figure 3 shows a detail as a section at the line III-III of Figure 2, and Figure 4 illustrates a detail variant.

The grease container includes a cylindrical outer housing or canister 1 containing an impervious flexible bag 3 which when charged with grease substantially fills the canister. Within the bag is a rigid element in the form of a tubular liner or shroud 2 extending from the mouth of the bag about half way to the closed end of the bag.

The bag is sandwiched between the liner 2 and the canister wall and the mouth of the bag is sealed around an end plate 4.

Specifically the canister wall, the liner 2 and an annulus 4a projecting from the end plate 4 are turned over and crimped together to provide a leak-proof seal. The bag 3 is completely filled with grease in such manner that all air is excluded and, during operation of the equipment, grease is slowly withdrawn from the canister and the bag 3 collapses so that it eventually adopts the configuration shown in broken lines at the left hand side of Figure 1.

The purpose of the liner or shroud 2 is to ensure that the bag 3 is prevented from collapsing in such manner than the outlet from the canister is closed before all the grease has been withdrawn. The closed end part of the bag 3 collapses into the liner 2 and, since the liner is approximately hall the initial height of the bag, the collapse continues until the bag is in a completely reentrant shape. The outer housing 1 is provided with a vent aperture 5 to allow entry of air into the housing as the grease is withdrawn from the bag 3. The end plate 4 has an outlet through a central cylindrical portion 4b which is provided with an internal thread formation which cooperates with a threaded boss 10 forming the inlet of a pneumatically operated pump 11, a seal 12 being provided which prevents external leakage of grease and internal leakage of air.

In use, movement of a large piston 16 of the pump within a cylinder 23 under the action of a spring 17 and consequent movement of a small piston 18 in a cylinder 19 causes a reduction in the pressure within the cylinder 19 of the pump thereby inducing a flow of grease from the canister past a disc valve 20. Air under pressure is applied through a port 21 and is controlled by an air valve in the duct 27 operated by a solenoid 28. Under pressure, the large and small pistons 16 and 18 are displaced to the right, i.e. inwardly of the cylinder 19 and the grease is delivered from the pump cylinder 19 via a discharge orifice 22 to meters (not shown) which control the amount of grease to be supplied to a lubrication point of a vehicle or other machine.

Return movement of the grease to the canister is prevented by the disc valve 20.

The end of the cylinder 23 to which the compressed air is supplied is closed by an end plate 25 and an O-ring 24 which are held in position by a circlip 26. When the air in cylinder 23 is vented to atmosphere, the spring 17 moves the large piston 16 outwardly of the cylinder and the cycle of operations starts again. The timing of the cycle is controlled by an electric timer (not shown) which operates the solenoid air valve, the period for which compressed air is supplied to the cylinder 23 being thus adjustable to suit the components to be lubricated.

One or more windows 29, indicated in Figure 2 only, may be formed in the wall of the canister or outer housing 1 so that the user of the equipment can observe the state of collapse of the bag 3.

In order to provide a remote indication that the bag is empty, the pump is fitted with a switch responsive to the pressure in cylinder 19 or to an abnormally large stroke of the pistons 16 and 18. As shown in Figure 3 an insulated spring-loaded contact 30 projects into the path of piston 16 for the purpose of signalling an abnormally large stroke. When the bag in the canister is depleted of grease, the pressure stroke of piston 16 increases as the result of low pressure in cylinder 19 and the piston engages and earths the contact 30, which is connected to the timer by a lead 31. The earthing is arranged to result in the lighting of an indicator lamp disposed for example in the cab of- a vehicle to warn the driver that the grease container needs to be replaced.

In the variant shown in Figure 4, a pressure responsive switch 32 is fitted. A small spring strip 33 is attached to the end plate 4 so that, as the bag 3 collapses when it is almost empty, continued withdrawal of the grease causes the spring strip 33 to deflect to reduce the cross-sectional area of the gap 34 through which the grease has to pass.

This reduction in area results in a reduction in pressure within the cylinder 19 during an outward stroke of the pistons 16 and 18, the reduction in area being related to the degree by which the pressure is reduced. The pressure-sensitive switch 32 then responds to a predetermined pressure reduction to actuate a warning light or indicator to inform the user of the equipment that the canister should be replaced.

The described apparatus is particularly applicable in the case of an installed lubrication system, the pump having a mounting bracket 35 for installation and being connected to an installed air pressure line and wired into supply, timer and indicator circuits.

The container is prepared by completely filling the bag with grease under controlled conditions such that all air is excluded, and applying a screw closure plug (not shown) to the opening 4b. It is supplied in this prepared state and can be stored until required for use. when put to use it remains sealed against ingress of air and contaminants and the bag collapses as grease is withdrawn until practically all the grease has been used. Another prepared container is then fitted by way of replacement. The advantages of using the replaceable container instead of a reservoir replenished periodically by a maintenance engineer are that cleanliness is ensured in that the grease is at all time enclosed to protect against the entry of dirt into the grease and hence into the lubricated vehicle or machine, and also that the grease is delivered with little wastage and without pumping troubles due to air ingress. Where grease is drawn from a conventional reservoir periodically filled there is risk of dirt entry and also of a cavitation cone forming in the centre of the grease such that air tends to enter the pump at an early stage and while the reservoir is still partly full, these defects being overcome only by frequent routine inspection.

WHAT WE CLAIM IS: 1. A container for grease or other flowable material to be dispensed, comprising an outer housing in the form of a canister having an end closure plate which provides an outlet through a coupling element, an impervious fiexible bag filling in the canister and sealed at its mouth around said outlet, there being provided within the bag a fixed tubular liner which extends away from the closure plate so that as the canister is emptied the part of the bag remote from the outlet collapses into the liner.

2. A container according to claim 1, wherein the length of the liner is half the length of the bag from the mouth thereof.

3. A container according to claim 1 or claim 2, including a window in the canister for viewing the state of collapse of the bag.

4. A container according to any one of the preceding claims coupled to a pump arranged to withdraw material through said outlet and to discharge the withdrawn material under pressure and means associated with the pump responsive to a condition thereof which indicates that the container needs to be replaced.

5. A container coupled to a pump according to claim 4, including a pressureresponsive electrical switch subject to the grease pressure in the pump.

6. A container coupled to a pump according to claim 5, including a springloaded electrical contact disposed in the pump for completing a warning circuit when the pump throw is abnormally large.

7. A lubrication system comprising a pump with mounting means for installation, a replaceable grease container according to any one of the preceding claims and coupled to the pump inlet 8. A container for grease or other flowable material to be dispensed, substantially as herein described with reference to Figures 1, 2 and 3 or Figures 1, 2 and 4 of the accompanying drawings.

9. A lubrication system according to claim 7, and substantially as herein described with reference to the accompanying drawings.

**WARNING** end of DESC field may overlap start of CLMS **.

Claims (9)

**WARNING** start of CLMS field may overlap end of DESC **. cone forming in the centre of the grease such that air tends to enter the pump at an early stage and while the reservoir is still partly full, these defects being overcome only by frequent routine inspection. WHAT WE CLAIM IS:

1. A container for grease or other flowable material to be dispensed, comprising an outer housing in the form of a canister having an end closure plate which provides an outlet through a coupling element, an impervious fiexible bag filling in the canister and sealed at its mouth around said outlet, there being provided within the bag a fixed tubular liner which extends away from the closure plate so that as the canister is emptied the part of the bag remote from the outlet collapses into the liner.

2. A container according to claim 1, wherein the length of the liner is half the length of the bag from the mouth thereof.

3. A container according to claim 1 or claim 2, including a window in the canister for viewing the state of collapse of the bag.

4. A container according to any one of the preceding claims coupled to a pump arranged to withdraw material through said outlet and to discharge the withdrawn material under pressure and means associated with the pump responsive to a condition thereof which indicates that the container needs to be replaced.

5. A container coupled to a pump according to claim 4, including a pressureresponsive electrical switch subject to the grease pressure in the pump.

6. A container coupled to a pump according to claim 5, including a springloaded electrical contact disposed in the pump for completing a warning circuit when the pump throw is abnormally large.

7. A lubrication system comprising a pump with mounting means for installation, a replaceable grease container according to any one of the preceding claims and coupled to the pump inlet

8. A container for grease or other flowable material to be dispensed, substantially as herein described with reference to Figures 1, 2 and 3 or Figures 1, 2 and 4 of the accompanying drawings.

9. A lubrication system according to claim 7, and substantially as herein described with reference to the accompanying drawings.