WO2010097668A1

WO2010097668A1 - Tank filler spout with closure valve

Info

Publication number: WO2010097668A1
Application number: PCT/IB2010/000261
Authority: WO
Inventors: David Biraud
Original assignee: Agco Sa
Priority date: 2009-02-27
Filing date: 2010-02-11
Publication date: 2010-09-02
Also published as: GB0903370D0; GB2468147A

Abstract

A filler spout assembly for fitting to an orifice in a wall of a liquid storage tank is provided. The assembly comprises a tube (18) which extends into the tank (10) from the orifice (14). The tube (18) serves to deliver liquid into the tank during a filling process. The lowermost end of the tube has a ball check valve fitted thereto. The valve comprises a ball (22) which closes the end of the tube (18) when in a closed position. The ball (22) falls under gravity into an open position when not held closed by a closure member (26). The assembly further comprises a float (32) connected to a lever (34) which cause the closure member (26) to force the ball into the closed position when the float (32) rises into a raised position.

Description

DESCRIPTION

TANK FILLER SPOUT WITH CLOSURE VALVE

The invention relates to filler spouts for liquid storage vessels and in particular relates to means to limit the maximum fill level of the vessel.

In storage vessel applications it is often desirable to limit the maximum fill level reached when the vessel is being filled. For example, an exhaust treatment storage tank fitted to a tractor is preferably left with a pocket of air at the top of the vessel at all times. In order to prevent freezing of the treatment fluid in the system during cold weather, means are often provided to drain the pipes and pump the fluid back into the tank. Therefore, an available volume for this retrieved fluid is required.

Furthermore, space at the top of the tank is often desired to allow for expansion of the fluid contained therein, for example upon freezing.

It is an object of the invention to provide a filler spout assembly with means to limit the maximum fill level of a liquid storage tank which is cheap and simple to implement.

According to the invention there is provided a filler spout assembly for fitting to an orifice in a wall of a liquid storage tank, the assembly comprising a tube which extends into the tank from the orifice and serves to deliver liquid into the tank during a filling process, the end of the tube remote the orifice having a ball check valve fitted thereto and comprising a ball which is moveable under gravity from a closed position, in which the ball closes the end of tube, to an open position, the assembly further comprising a float connected to a lever, and a closure member arranged to force the ball into the closed position when the float rises into a raised position. By providing a closure member which forces the ball into closed position in response to movement of the float a simple yet effective automatic level limitation is provided using mechanical components.

The assembly preferably further comprises retaining means which serves to hold the ball in position relative to the tube. The retaining means may also serve to guide the ball between the open and closed positions. In a preferred arrangement the retaining means comprises a cage like structure which allows the free flow of liquid as it enters into the tank through the tube. The lever and closure member are preferably pivotally connected to the retaining means to allow movement around a substantially horizontal axis. This allows the float to move within a range of movement in an arc around the horizontal axis. A stop member may be included which acts upon the retaining means and serves to limit the lower movement of the float so as to prevent the lever from reaching a vertical position in which a rising fluid level would be ineffective.

The lever and closure member are preferably integrated into a single component to increase ease of manufacture and assembly whilst also lowering the cost.

The closure member may include a cam-type arrangement which acts directly upon the outside surface of the ball. In this case, the cam may present a small projection which allows the ball to drop into an open position thus allowing fluid to enter through the tube and into the tank. Conversely, when the float rises into a raised position (corresponding to the maximum fill level of the tank) the closure member presents a larger projection which forces the ball upwards into the closed position.

Preferably, the end of the tube remote the orifice comprises a narrowed bore which provides seating of the ball thus improving the sealing effect.

The filler spout assembly in accordance with the invention may be fitted to any liquid storage tank which requires means to limit the maximum fill level of the tank. However, the invention lends itself particularly well to liquid vessels associated with a vehicle such as car or tractor and is not limited to fuel storage. For example, the filler spout assembly may be fitted to treatment storage tanks which store engine exhaust treatment fluid for reducing harmful emissions.

Fluid tanks, especially on tractors which require fitting around various components, are often irregularly shaped. This has been found to cause a problem when fitting level gauges for example wherein the filler spout is disposed higher up in the tank. Upon filling the tank, the maximum level reached may far exceed the highest usable part of the level gauge thus rendering a reliable measurement impossible. By installation of the filler spout assembly in accordance with the invention, the maximum level in the tank can be predetermined thus keeping the level of the fluid within the bounds of the gauge at all times.

Further advantages of the invention will become apparent from the following description of a specific embodiment in which:- Figure 1 is a sectional view through part of a liquid storage tank fitted with a filler spout assembly in accordance with the invention and shown with the ball check valve in the closed position;

Figure 2 is a sectional view of the assembly of Figure 1 shown with the ball check valve in the open position;

Figure 3 is a perspective exploded view of the filler spout assembly of Figure 1;

Figure 4 is a front view of the lower end of the filler spout assembly of Figure 1 ;

Figure 5 is a side view of the lower end of the filler spout assembly of Figure 1 ; and,

Figure 6 is a sectional view through the lower part of the filler spout assembly of

Figure 1 showing the ball check valve in the closed position.

With reference to the drawings, a liquid storage tank 10 is located on a vehicle (not shown) and is arranged to store diesel exhaust fluid (DEF) such as urea solution. The tank 10 is typically formed of blow moulded plastic although the makeup of the tank is not of significant relevance to the understanding of the invention.

A filler spout assembly 12 is secured in position in an orifice 14 which is formed in a wall 15 by appropriate securing means. The assembly comprises a filler cap 16 which can be removed in a known manner by a simple unscrewing action. The cap 16 serves to cover the filler spout during normal operation of the vehicle and prevent dust from entering.

The assembly 12 comprises a tube (or neck) 18 which extends into the tank 10 from the orifice 14. The tube 18 is secured in position so that its outermost end is flush with the tank wall 15 and is sealed in position to prevent leakage of the stored liquid. The tube 18 comprises a circular cross section which is uniform over its upper region.

During a filling process the cap 16 is removed and a filling nozzle (not shown) is inserted into the tube 18 from the outside. The filling nozzle ejects treatment fluid into the tank 10 through the tube 18. The lower end of the tube 18, that is the end remote the orifice 14, comprises a region having a narrowed bore 20 which provides a seat for a ball 22 of a ball check valve. Retaining means 24 includes a cage which retains the ball 22 whilst also allowing fluid to flow through the narrowed bore 20 into the tank 10.

The ball 22 is moveable from a closed position (Figure 1), in which the ball 22 closes the end of the tube 18, to an open position (Figure 2) in which fluid can flow freely through the tube 18 and into the tank 10. Gravity provides the force which moves the ball 22 from the closed position into the open position. In accordance with the invention a closure member 26 provides the force to move (and hold) the ball 22 into the closed position as will be described below.

With reference to Figure 3, a spindle 28 is secured between two holes 29 along the lower edge of retaining cage 24. A pivoting member 30 is pivotally connected to the retaining cage 24 by the spindle 28 to allow movement around the horizontal axis defined by spindle 28. A float 32 in the form of a spherical ball is secured to the pivoting member 30 in the end of one of three extensions which forms a lever 34. A second extension of the pivoting member 30 forms the aforementioned closure member 26 whilst a third extension provides a stop member 36 which will be described below.

With reference again to Figure 2, when the level 40 of the treatment fluid is low in tank 10, float 32 drops to its lowermost extent which is determined by stop 36 which acts upon the lower edge of retaining cage 24. Closure member 26 presents a minimal cam-protrusion to the lower surface of ball 22 thus allowing it to fall under gravity into an open position in which fluid can enter the tank freely through tube 18.

The dimensions of stop 36 are such that the angle of lever 34 does not reach a vertical position. This ensures that any rise in level 40 can effect a movement in float 32.

As the filling process continues the level of treatment fluid 40 rises to an extent where it comes into contact with float 32. Due to displacement physics the float 32 rises with the fluid level 40 and causes a rotational movement of pivoting member 30 around the axis defined by spindle 28. As shown in Figure 1 this causes closure member 26 to present a larger cam- protrusion to ball 22 thus forcing it upwards into a closed position in which ball 22 seats in a sealed manner in narrowed bore region 20. Upon effective sealing of the lower end of tube 18 further filling of the tank 10 is prevented. The filler spout assembly 12 as described allows a maximum fill level of the tank 10 to be predefined below the level of ball 22 using simple mechanical components. The mechanics provided by lever 34 ensures that the ball check valve remains closed regardless of the height of the fluid column which congregates in tube 18.

During a filling process using a filler pistol with automatic deactivation means, the closure valve closes the end of the tube when the level of fluid in the tank reaches a level sufficient to raise the float 32. The sealing provided by lifted ball 22 is sufficient to limit the flow into the tank thus causing back-filling of the tube 18. This, in turn, causes the filler pistol to shut-off as it senses the raised level of fluid.

In summary, there is provided a filler spout assembly for fitting to an orifice in a wall of a liquid storage tank is provided. The assembly comprises a tube which extends into the tank from the orifice. The tube serves to deliver liquid into the tank during a filling process. The lowermost end of the tube has a ball check valve fitted thereto. The valve comprises a ball which closes the end of the tube when in a closed position. The ball falls under gravity into an open position when not held closed by a closure member. The assembly further comprises a float connected to a lever which cause the closure member to force the ball into the closed position when the float rises into a raised position.

Claims

1. A filler spout assembly for fitting to an orifice in a wall of a liquid storage tank, the assembly comprising a tube which extends into the tank from the orifice and serves to deliver liquid into the tank during a filling process, the end of the tube remote the orifice having a ball check valve fitted thereto and comprising a ball which is moveable under gravity from a closed position, in which the ball closes the end of tube, to an open position, the assembly further comprising a float connected to a lever, and a closure member arranged to force the ball into the closed position when the float rises into a raised position.

2. An assembly according to Claim 1, further comprising retaining means to hold the ball in position relative to the tube.

3. An assembly according to Claim 2, wherein the lever and closure member are pivotally connected to the retaining means to allow movement around a substantially horizontal axis.

4. An assembly according Claim 3, further comprising a stop member which acts upon the retaining means and serves to limit the lower movement of the float to prevent the lever from reaching a vertical position.

5. An assembly according any preceding claim, where the lever and closure member are integrated into a single component.

6. An assembly according to any preceding claim, wherein the closure member includes a cam-type arrangement which acts directly upon the outside surface of the ball.

7. An assembly according to any preceding claim, wherein the end of the tube remote the orifice comprises a narrowed bore which the outside surface of ball closes when in the closed position.

8. A liquid storage tank fitted with a filler spout assembly according to any preceding claim.

9. A tank according to Claim 8, wherein the float is positioned to limit the maximum fill level of the tank which is below the ball.