MXPA97005895A - Sprayer with precompress pumps - Google Patents

Abstract

The present invention relates to a sprayer with a precompression pump, comprising a pump housing having a pump cylinder, a pump piston mounted for reciprocal movement inside said cylinder to define a variable volume pumping chamber, said piston has a hollow stem defining a discharge passage, a discharge valve seat in said passage facing said chamber, a discharge valve member mounted for reciprocal movement in said housing, said valve member comprises a spring valve in coupling sealing with said valve seat in a closed discharge position, means for the reciprocal movement of said piston and said valve member substantially in unison against the diagonal of a return spring, diversion means within said housing located outside of alignment with a central longitudinal axis of said housing, said means of deflection extending towards said valve member in the path of reciprocal movement of a lower end of said valve member, said lower member impacting against said deflection means during the downward stroke movement of said piston to deflect said lower end away. said axis for mounting said poppet valve to disrupt the sealing engagement of said poppet valve with said valve seat for expelling entrapped air from said pump chamber through said passage downlds

Description

BACKGROUND OF THE INVENTION This invention relates generally to a sprayer with a precompression pump and more particularly to a priming pump chamber arrangement for said sprayer.

As is known, the manually operated precompression pump sprayer, otherwise known as an accumulation pump sprayer, has a reciprocating relief valve member that opens the discharge at a minimum pumping pressure reached during pumping as the pump Pressure in the pumping chamber exceeds the strength of a return spring. The minimum pressure can not be reached to open the discharge while the pumping chamber contains air, which is compressible. Thus, for the precompression pump sprayer to function satisfactorily, the pumping chamber must be primed first, that is, the unwanted air in the chamber must be evacuated and replaced with liquid product to be dispensed.

An approach taken to prime the pumping chamber of a precompression sprayer is presented in U.S. Patent No. 4,051,983 wherein a longitudinally extending rib or groove is formed in the inner wall of the pump frame core in which the reciprocating discharge valve operates. A discharge valve nose, in the form of a head valve, normally rests against a relief of the discharge valve formed in the discharge passage of a hollow piston tube, under the action of an opposite return spring provided. by the return spring of the piston. At the minimum pressure, the head valve is forced in the opposite direction to its valve rest to open the discharge, in the known manner.

The valve head has a seal that seals the coupling with the bore in which the valve is reciprocal. As the air in the pumping chamber without priming is compressible, the piston and the head valve are lowered together when pressing the plunger. At or near the end of the downward movement of the plunger, the seal between the head seal and the wall of the tube in which the head operates is interrupted when the head seal is juxtaposed to the rib or groove. The air in the pumping chamber, which has now been compressed during the downward movement of the python, is evacuated from the pumping chamber directly into the container by the insertion hose that extends into the liquid product in the container. The compressed air flows through the hose by capillary action until the product partially fills the pumping chamber with each subsequent upward movement that attracts liquid product to the pumping chamber. As the liquid product partially fills the pump chamber, it prevents the remaining volume of air in the pump chamber from being evacuated beyond the head seal and into the container. This remaining volume of air must now be purged from the chamber to avoid expedition through the discharge orifice causing undesirable uneven bubbling and dew.

Another approach taken in the priming of the pump chamber of a precompression pump sprayer is exemplified by US Pat. No. 5,064,105 wherein one or more small protuberances are formed in the wall of a pump chamber to deform the pump. Piston seal at or near the end of the downward movement of the piston which allows unwanted air from the pumping chamber to be evacuated inside the container via a side port formed in the pump frame.

Still another approach provided for priming the chamber is presented in U.S. Patent No. 4,923,094 in which the head valve has a radially outwardly extending base which, at the end of the downward movement of the plunger, comes into contact with a projection on an inner wall of the closure forming a priming passage to cause the valve seal of the head to be changed from its confronting wall to open a path to evacuate air from the pumping chamber in the container via a vent of the container.

SUMMARY OF THE INVENTION It is an object of the present invention to provide a means for priming the pumping chamber of a precompression pump sprayer in a simple yet highly efficient and economical manner, said means for further use or in lieu of prime priming means. known pumps. According to the invention, the air is purged from the pumping chamber by means of the discharge orifice by means of the seal of the head rest.

Upon reaching this objective, a fixed priming ramp which may be molded in the pump frame extends towards one end of the discharge valve member in the path of reciprocation thereof so that, at or near the end of the movement toward under the piston, the lower end of the valve member is diverted to one side by the ramp. The valve member, in the form of a normally coaxial head valve with a discharge valve rest formed in the piston. When deflected the head is tilted to one side to interrupt the seal of the discharge valve to allow air to escape from the pump chamber into the atmosphere via the discharge orifice.

Other objects, advantages and novel features of the invention will be more apparent from the following detailed description when taken in conjunction with the accompanying drawings.

BRIEF DESCRIPTION OF THE DRAWINGS Figure 1 is a vertical sectional view of the sprayer with precompression pump according to the invention illustrated in its rest condition; Figure 2 is a view similar to that of Figure 1 showing the piston in a downward movement position when priming the pump; Y Figure 3 is a sectional view taken substantially along line 3-3 of Figure 2.

Detailed Description of the Invention Now referring to the drawings in which the similar reference character refers to similar and corresponding parts in all views, the sprayer with manually operated precompression pump is illustrated in its rest condition in Figure 1 and is generally denotes 10. The pump comprises a pump frame 11 in the form of a gradual cylinder having a large diameter cylindrical section 12 and a smaller diameter cylindrical section 13. The former forms a frame for the return spring of the piston 14, an entry passage 15 that has an entry port 16 and supports an immersion hose 17 extending inside the container (not shown) of the liquid product to be dispensed.

The frame 11 is press-fitted or otherwise securely mounted to a crown portion 18 of the closure 19 illustrated with internal cord for mounting the pump sprayer to the neck of the container (not shown).

The pump sprayer further comprises a pump piston 21 having a piston seal 22 in sliding seal coupling with the cylindrical section 12 for this defining a variable volume pumping chamber 23. The piston includes a hollow piston tube 24 which defines a discharge passage 25, a plunger head 26 which is mounted to the tube and which facilitates manual operation by the user.

The discharge passage communicates inside the head with a discharge orifice 27 of an orifice cup 28 mounted on the head and which, together with a head probe 29, defines turning mechanics for imparting twist or swirl to the liquid product under pressure so that it is expelled through the hole in the form of a fine mist.

The pump sprayer further includes a discharge valve member 31 which may be a hollow part molded part having a conical nose portion 32 which forms a head valve and which has a deformable annular seal 33 between the opposite ends. The seal 33, which extends conically upwards in the shape of a chevron, is normally in slidable seal engagement with the inner wall of the cylindrical section 13.

To prime the pump chamber according to this invention, the pump frame has a molded priming ramp 34 positioned within the lower end of the section 13, which extends upwardly of the valve member 31 and which is positioned in the path of the pump. the bottom end wall 35 of the valve member. The priming ramp 34 has a wall that slopes slightly in a given direction in the opposite direction of the longitudinal axis of the pump frame 11.

A rest 37 for the discharge valve is formed in the discharge passage 25 at a lower end thereof confronting the pumping chamber. The relief for the discharge valve may be in the form of a circular edge defined at the intersection between the inner cylindrical wall 38 of the piston tube and the conical wall 39 at the inner terminal end of the discharge passage 25. The conical wall may have the shape of a slope different from the nose portion 32 so as to define a discrete circular edge for the rest of the discharge valve.

To prime the pump, the head of the plunger 26 is manually pressed against the counteracting force of the return spring 14 extending between the lower end of the cylindrical section 13 and the underside of an annular shoulder 14 formed below the seal of the chevron 33. The compressible air within the pumping chamber is compressed during movement towards the piston and the valve member 31 is lowered together with the piston to the position of Figure 2. Since the priming ramp 34 is placed only on one side of the central axis of the pump frame, with its sloping end wall 36 in alignment with the bottom end wall 35 of the valve member, the wall 35 is hit against the wall end slope 36 in the position of Figure 2 to deflect the lower portion of the valve member 31 to the right as seen in Figure 2. This deflection causes the nose portion 32 of the valve member to deviate to the left as seen in Figure 2 around the seal 33 that acts as a pivot. In other words, the valve member 31 is tilted in relation to the central axis of the pump frame, so that the axes of the valve member and the pump frame, which now coincide before hitting the priming ramp, coincide now. to the impact as seen in Figure 2.

This momentary deviation or tilting of the valve member interrupts the seal between the nose portion 32 and the rest of the discharge valve 37 and forms a slightly open opening 42 (Figure 3) to momentarily open the discharge. Thus, any air that has been trapped in the pumping chamber is compressed and escapes into the atmosphere through the open aperture 42, the discharge passage 25 and the discharge orifice 27.

In the next upward movement, as the operator releases the downward pressure on the plunger head allowing the piston to return to its position of Figure 1 under the force of the return spring, the head is fully readied again, the volume of the pumping chamber expands and sucks product up through the insertion hose and through the port 16 and the passage 15 into the pumping chamber 23. The liquid, under the atmospheric pressure in the container exceeding the pressure of the sub-atmosphere in the expanding pumping chamber fills the chamber as the chevron seal 33 passes in or near the upward movement of the valve member. The liquid can be admitted into the pumping chamber as the seal 33 rises slightly out of and / or is forced in the opposite direction from the inner wall of the cylindrical section 13.

One or two complete movements as those previously mentioned should be sufficient to fully prime the pump. Thus, the approach to prime the pump according to the invention may be the only priming provided for the pump sprayer. Otherwise, the present approach can be used in addition to known priming means such as that provided for the pump sprayer of the 4,051,983 patent.

For example, a protrusion 43 or equivalent groove may be provided in the inner wall of the frame section 13 at a predetermined location. Thus, during priming, when the valve member 31 is at or near the end of its downward movement, the chevron seal 33 makes contact with the protrusion 43 (or groove) thereby breaking its sealing action with the interior wall of the section. 13 to allow any air in the pumping chamber to be evacuated directly into the container by the insertion hose, as described in the '080 patent.

Any unwanted air remaining in the pumping chamber, when using the priming means of the invention, will be evacuated from the pumping chamber through the opening 42 and the discharge passage to the atmosphere via the discharge orifice.

Similarly, if the pump priming means is in the form of a protrusion provided in the wall of the pumping chamber at the lower end to distort the piston seal to evacuate air from the chamber through the side port , similarly as in the patent 5,064,105, the priming means according to the invention can be provided in lieu of or in addition to said known priming means.

From this it can be seen that a more highly effective simple approach has been taken in the evacuation of the unwanted air from the pumping chamber of a precompression pump sprayer to the atmosphere through the discharge orifice simply causing the member Head valve is tilted to one side to momentarily interrupt the seal of the discharge valve forming a slight opening through which unwanted air is released.

Obviously, many modifications and variations of the present invention are possible in light of the above teachings. It should be understood therefore that within the scope of the appended claims the invention can be practiced in a manner other than that specifically described.

Claims (7)

1. Claims 1. A sprayer with a precompression pump, comprising a pump frame having a pump cylinder, a pump piston mounted for reciprocation within said cylinder so as to define a variable volume pumping chamber, said piston having a hollow tube defining a discharge passage, a rest for the discharge valve in said passage facing said chamber, a discharge valve member mounted for reciprocation within said frame, said valve member comprising a valve head in sealing engagement with said valve rest in a closed discharge position, means for reciprocating said piston and said valve member substantially in unison against the impulse of a return spring, means deflecting inside said frame placed out of alignment with a central axis of said valve. frame, said diverting means extend towards said valve member in the path of reciprocation a lower end thereof, said lower end is struck against said diverting means during the downward movement of said piston to deflect said lower end in the opposite direction of said axis to tilt the repose of the valve to issue the air trapped in said pumping chamber through said discharge passage.
2. 2. The pump sprayer according to claim 1, wherein said valve member has an inlet valve seal in contact with a wall of a reduced diameter section of said frame to control a supply passage to said pump chamber, said frame it has means cooperating with said inlet valve seal during the downward movement of said piston to deliver trapped air from said chamber out of said frame through said inlet passage.
3. 3. The pump sprayer according to claim 1, wherein said diverting means comprises a priming ramp.
4. . 4. The pump sprayer according to claim 2, wherein said cooperating means comprise at least one longitudinal priming rib on said wall of said section.
5. 5. The pump sprayer according to claim 3, wherein said priming ramp has a surface that slopes in the opposite direction to the central axis.
6. 6. The pump sprayer according to claim 1, wherein said piston has a piston seal in slidable sealing engagement with said cylinder, said rest of the relief valve is positioned at one end of said discharge passage adjacent to said seal. piston.
7. 7. The pump sprayer according to claim 1, wherein said discharge valve comprises a head valve having a conical nose portion engageable with said discharge valve rest. EXCERPT OF THE INVENTION A precompression pump sprayer is primed by the provision of a priming ramp to deflect the lower end of a head valve member at the end of the downward movement of the plunger to tilt the valve member to disrupt its action of sealing with the rest of the discharge valve allowing the air to be released from the pumping chamber through the discharge orifice and into the atmosphere.