Patent ID: 12188460

SUMMARY

A liquid delivery system includes a reciprocating drive. The reciprocating drive is coupled to a reciprocating paint pump piston by a coupler. The coupler includes a collar assembly, an elastic member and a sheath.

The above summary is not intended to describe each illustrated embodiment or every implementation of the present disclosure.

DETAILED DESCRIPTION

For the sake of illustration, but not by limitation, aspects of the present disclosure relate to reciprocating liquid pumps. While examples below are illustrated in the context of paint, it is noted that the present features can also be applicable to pumps for use with other types of liquids as well. Further, while examples below are illustrated in the context of a hydraulic-powered reciprocating drive, it is noted that the present features can also be applicable to other types of reciprocating drives as well.

Many paint delivery systems that employ paint pumps are subject to significant wear and tear over their lifetime. It is desired to have a system that allows a user to easily remove the paint pump from its reciprocating drive, for example for cleaning, maintenance, and/or to replace parts.

FIG.1is a perspective view showing an example paint delivery system100. Paint delivery system100includes a frame128, wheels130, a motor system102, a solenoid valve103, a pump assembly106, and a paint reservoir (not shown). Motor system102drives a hydraulic pump which pumps hydraulic fluid to/from a hydraulic fluid reservoir. Motor system102as shown is a gasoline powered engine. However, in other examples motor system102can be electrically powered, hydraulically powered, diesel powered, Power Take Off (PTO) powered, etc. The hydraulic pump and hydraulic fluid reservoir are located generally at reference number135. The hydraulic pump delivers hydraulic fluid (e.g., oil) from the hydraulic fluid reservoir to solenoid valve103. Solenoid valve103includes a solenoid, a valve body, a head port on the valve body, and a rod port on the valve body. The head port on the valve body and the rod port on the valve body can be controlled by an electric current through the solenoid. Solenoid valve103can alternate the flow from the head port on the valve body and the rod port on the valve body through conduits105to ports122and124on hydraulic cylinder114, respectively.

As shown, solenoid valve103is coupled to a controller140. Controller140can include a variety of different hardware and/or software components. In one example, the controller comprises a MOSFET and flip-flop integrated circuit system. In another example, the solenoid of solenoid valve103is controlled by a computer processor and integrated software, for example a circuit board. The circuit board can be communicably coupled, directly to the solenoid of solenoid valve103. Controller140can also be coupled to a memory, such that the controller can report, or store, collected information from a cycle counter and/or a run-time tracker. Controller140can be useful to measure performance of the pump system without manual cycle counting. As shown controller140is proximate solenoid valve103, however, controller140may be located elsewhere.

Pump assembly106includes a hydraulic cylinder114and a paint pump116. Solenoid valve103directs the hydraulic fluid, generated by the hydraulic pump, through the head port on the valve body through a conduit105to a head port122of hydraulic cylinder114. As the hydraulic fluid is directed by the solenoid valve through head port122of hydraulic cylinder114, pressure builds in the cylinder and forces the hydraulic piston to move towards rod port124. As the hydraulic piston moves through cylinder, the hydraulic fluid is forced through rod port124of hydraulic cylinder114, through a conduit105into solenoid valve103through the rod port on the valve body and returned to the hydraulic fluid reservoir.

In one example, as the hydraulic piston moves from the head port122through the cylinder114to rod port124, a ferrous metal located on the hydraulic piston rod moves closer to a first hall effect sensor (not shown inFIG.1) at a stroke limit position. When the hydraulic piston has reached the stroke limit position in the cylinder, the ferrous metal is be detected by the first hall effect sensor. In response to detecting the ferrous metal, the hall effect sensor sends a sensor signal to the controller140. In response, controller140controls the solenoid in solenoid valve103to change states.

Once the solenoid state changes, the hydraulic fluid flowing from the hydraulic pump can flow through solenoid valve103, through conduit104into rod port124of hydraulic cylinder114. Moreover, the hydraulic fluid can be pushed back through head port122of hydraulic cylinder114, through conduit105, into solenoid valve103, and returned to the hydraulic fluid reservoir. When the hydraulic piston has reached a second stroke limit position, the ferrous metal located on the hydraulic piston rod, causes a second hall effect sensor (not shown inFIG.1) to detect the position of the rod. Controller140receives a signal from the second hall effect and then controls the solenoid to change states such that hydraulic fluid flow again reverses. This cycle is repeated such that the hydraulic piston moves in a reciprocating manner. In other examples, the hydraulic piston can be reciprocated in other ways as well.

As the hydraulic piston rod reciprocates, a paint piston rod (not shown inFIG.1), operably coupled to the hydraulic piston rod, also reciprocates. As a result, the paint piston rod pumps paint through paint pump116from the paint reservoir to an outlet hose134connected to a paint applicator (not shown inFIG.1).

Pump assembly106is coupled to linear guides131that allow vertical movement of pump assembly106. Actuator133retains pump assembly106in place and/or actuates pump assembly106to raise and lower. As shown, actuator133includes an electric motor and screw drive. In other examples, actuator133can include other items as well. As shown, pump assembly106can be raised such that paint intake216can be coupled to the bottom of paint pump116. Once paint intake216is coupled to paint pump116, pump assembly106can be lowered such that the weight of pump assembly106and/or paint pump116is supported by the ground, bottom of a fluid reservoir, or other surface.

FIGS.2A-2Dshow views of pump assembly106, in one example.FIG.2Ais a front perspective view of a portion of pump assembly106. In this view, cover101is coupled to one or more components of pump assembly106. Cover101can protect internal components from external conditions. Cover101can also prevent items from getting caught in the reciprocating motion of the paint pump. In some examples, cover101is at least semi-transparent.

FIG.2Bis a perspective view of a portion of pump assembly106, with cover101removed to expose sensor204, sensor206, coupler213, hydraulic rod210and paint rod212. Sensor204and sensor206sense the location of coupler213. In some examples, sensors204and sensor206correspond to minimum and maximum positions of coupler213. Coupler213couples hydraulic rod210to paint rod212, and hence, the location of coupler213is indicative of the positions of hydraulic rod210and paint rod212. Therefore, when sensor204or sensor206detects coupler213, the sensor output is also indicative of the location of hydraulic rod210and paint rod212(e.g., these rods reaching a minimum or maximum stroke limit).

As shown, in the present example, minimum sensor204and maximum sensor206are hall effect sensors that can detect the change in an electromagnetic field. In other examples, minimum sensor204and maximum sensor206could include different types of sensors. As shown, both minimum sensor204and maximum sensor206include a magnet that generates a magnetic field. When coupler213comes within a threshold distance from the magnet, the magnetic field changes in a detectable way. This change is indicative of coupler213being at either location proximate the minimum sensor204or maximum sensor206. The locations of minimum sensor204and maximum sensor206can be relative to coupler213, in such a way, that when coupler213reaches either sensor, the hydraulic rod210and/or paint rod212is either at their maximum or minimum stroke position.

Illustratively shown in these figures the source of reciprocating motion is hydraulic rod210which is part of a hydraulic drive system. In other examples, hydraulic rod210can be replaced by a different reciprocating mechanism that is driven in a different way.

FIG.2Cis a sectional view of pump assembly106taken along plane corresponding to C-C shown inFIG.2A. As can be seen inFIG.2C, pump assembly106includes head port122of hydraulic cylinder114, rod port124of hydraulic cylinder114, a paint rod212, a hydraulic rod210, a hydraulic piston224, a paint intake216, a hydraulic cylinder cavity218, a minimum sensor204, maximum sensor206, and coupler213.

An actuator (e.g., solenoid valve103) directs a hydraulic fluid into hydraulic cylinder cavity218through head port122of hydraulic cylinder114. The hydraulic fluid forces hydraulic piston224to move down through hydraulic cylinder cavity218. As hydraulic piston224moves down through hydraulic cylinder cavity218, paint rod212moves down through paint pump cavity and pushes paint out a hose outlet (e.g., through a hose to paint applicator). In addition, hydraulic fluid is forced back through rod port124of hydraulic cylinder114, into the solenoid valve and returned to a hydraulic fluid reservoir.

In one example, when hydraulic piston224is at a stroke limit position, coupler213is proximate maximum sensor206, and maximum sensor206generates a sensor signal indicative of coupler213reaching the maximum position. In response to receiving the sensor signal, controller140reverses the state of the solenoid valve and causes the hydraulic fluid to flow into hydraulic cylinder cavity218through rod port124of hydraulic cylinder114, thereby reversing the direction of piston224. As piston224travels up, the hydraulic fluid is forced out of head port122of hydraulic cylinder114, into the solenoid valve and returned to the hydraulic fluid reservoir. Paint rod212also moves up through the paint pump cavity and draws the paint in through paint intake216. When the hydraulic piston has reached its upper stroke limit position, coupler213is sensed by minimum sensor204is reversed the hydraulic fluid flow into hydraulic cylinder cavity218through head port122of hydraulic cylinder114.

FIG.2Dis a sectional view showing an area of pump assembly106proximate coupler213, in greater detail. Coupler213includes a collar214, a sheath208, and an elastic member209. While examples below are illustrated in the context of elastic member209including an O-ring, it is noted that other types of elastic members can be utilized as well.

Collar214couples hydraulic rod210to paint rod212. Collar214includes collar elements215-1,215-2(collectively referred to as collar elements215), that fit over, and form a collar around, hydraulic rod210and paint rod212proximate interface217. In some examples, there may be more or fewer collar elements215. To keep collar elements215of collar214in contact with hydraulic rod210and paint rod212, O-ring209and/or sheath208are fit over the exterior surface of collar214to inhibit lateral movement of elements215of collar214relative to the stroke direction of hydraulic rod210and paint rod212.

Accordingly, O-ring209couples collar elements215together. O-ring209can also be sized such that it is compressed by sheath208. In some examples, the compression of O-ring209by sheath208applies a retaining force on sheath208such that sheath208is retained on collar elements215during cycling of piston224. As shown, O-ring209fits within channel219. Channel219keeps O-ring209in place around collar elements215.

FIG.3is a flow diagram showing an example operation300of removing a paint pump from a reciprocating drive. For sake of illustration, but not by limitation,FIG.3will be described in conjunction withFIGS.4A-4Dand in the context of assembly106shown above inFIGS.2A-2D. Operation300begins at block302where the pump assembly is optionally lowered until the paint intake216is resting on the ground or other surface such that paint pump116or other components are supported by the ground or other surface.

Operation300proceeds at block303where cover101is removed from pump assembly106.FIG.4Ashows an example where cover101is removed. In some examples, there may not be a cover101, in those examples, this step is not required.

Operation300proceeds at block304where sheath208is raised above collar214.FIG.4Bshows one example of this.

Operation300proceeds at block306where O-ring209is freed from collar214. As shown in at leastFIG.4B, a beveled area211can be provided to ease in freeing of O-ring209. Beveled area211is a type of finger groove that allows a user's finger or other tool access lower portions on O-ring209such that it can be lifted out of channel219.

Operation300proceeds at block308where O-ring209is raised and placed on rod210, as shown inFIG.4C. To facilitate positioning of O-ring209on rod210, in one example, O-ring209, at rest, has an inner diameter that is less than or equal to the outside diameter of rod210, such that O-ring209is deformed to fit on rod210and an elastic force/friction force of O-ring209retains O-ring209on rod210. The size and properties of O-ring209can be chosen such that when O-ring209deformed to fit on rod210it does not exceed a yield point. In some examples, O-ring209at rest has an inner diameter that is 90-98% of the outside diameter (or convex hull) of the rod210. In some examples, a feature can be included on rod210to help in retaining O-ring209. In some examples, O-ring209is placed on a different portion of assembly106other than rod210.

Operation300proceeds at block310where sheath208is rested on O-ring209.FIG.4Cshows an example where sheath208is rested on O-ring209. This allows a user to free their hand that would normally be used to hold sheath208above collar elements215. A common problem in current systems is that sheath208is unsupported and when the lower assembly is removed the sheath208can fall into the liquid source. Another common problem is that a user tries to hold sheath208and both collar elements215at the same time and one of the objects fall into the liquid source. Having a device that supports sheath208helps prevent these problems. O-ring209, in some examples, has a size and physical properties (e.g., elasticity, asperity, etc.) that allow it to support sheath208.

Operation300proceeds at block312where collar elements215are detached from rods210and212.FIG.4Dshows an example where collar elements215are detached from rods210and212.

Operation300proceeds at block314where paint pump116is removed from the assembly. Nut402can be loosened which releases paint pump116from the other components of pump assembly106. As noted in block302, the paint pump116may be supported by paint intake216, and thus a user can tip paint pump116away from the assembly without supporting the full weight of paint pump116.

FIG.5is a perspective view of an example pump coupler assembly. As shown, assembly500includes sheath208, collar elements215, and O-ring209. As shown elements215-1and215-2are substantially identical parts. In other examples, each element215-1,215-2may be different from one another. In some examples, collar elements215-1,215-2include machined portions. In some examples, collar elements215-1,215-2include cast portions. As shown, collar elements215include an exterior retaining channel that is configured to receive O-ring209. The exterior retaining channel can have a beveled portion (shown on element215-1) that allows for easy removal of O-ring209. In some examples, O-ring209is a geometric torus having a minor diameter that is greater than the depth of the exterior retaining channel of collar214, such that sheath208compresses O-ring209.

Collar elements215also include an interior channel (shown on element215-2) that receives portions of the reciprocating drive and paint pump to couple the reciprocating drive to the paint pump.

According to one example, a paint delivery system includes a reciprocating paint pump that is coupled to a reciprocating hydraulic piston by a coupler. The coupler includes two or more collar elements that are disposed over the interface between the reciprocating paint pump and the hydraulic piston. An interior channel of the two or more collar elements couple the reciprocating paint pump and the hydraulic piston, such that reciprocating motion of the hydraulic piston is transferred to the reciprocating paint pump. The two or more collar elements are held in place over the interface between the reciprocating paint pump and the hydraulic piston by an O-ring or other elastic device. The collar elements have an exterior retaining channel where the O-ring seats. The exterior retaining channel includes a beveled area that aides in removal of the O-ring by a user. A sheath can also be disposed over the collar elements and O-ring. When the sheath is placed over the O-ring, it compresses the O-ring. This compression also provides a friction force that keeps the sheath on the collar elements during pump operation.

The descriptions of the various examples of the present disclosure have been presented for purposes of illustration but are not intended to be exhaustive or limited to the examples disclosed. Many modifications and variations will be apparent to those of ordinary skill in the art without departing from the scope and spirit of the described examples. The terminology used herein was chosen to explain the principles of the examples, the practical application or technical improvement over technologies found in the marketplace, or to enable others of ordinary skill in the art to understand the examples disclosed herein.