US2311078A

US2311078A - Engine primer

Info

Publication number: US2311078A
Authority: US
Inventors: Arthur L Parker
Original assignee: Individual
Current assignee: Individual
Priority date: 1941-03-03
Filing date: 1941-03-03
Publication date: 1943-02-16
Anticipated expiration: 1960-02-16

Description

A. L. PARKER ENGINE PRIMER Feb. 16, 1943.

Filed March 5; 1941 m w M W 2 f Patented Feb. 16, 1943 UNITED srerssrarer OFFICE ENGINljl PRIMER Arthur L. Parker, Cleveland, Ohio Application March 8, 1941, Serial No. 381,553

' 9 Claims. I (01. 103 2 The present invention relates to new and useful improvements in a device for dispensing fluid to one or more selected points, and more particularly to improvements in a device of this type which is adapted to be used as a primer for engines.

In the prior patents of Arthur L. Parker, No. 1,934,878, dated November 14, 1933, No. 1,942,255, dated January 2, 1934, and No. 2,185,564, dated January 2, 1940, there are shown engine primers:

of this general type and the present invention relates to certain novel improvements in connection therewith. The invention is illustrated particularly in connection with the type of primer shown in the Parker Patent No. 2,185,564 al--' though it is to be clearly understood that other types of primers may be employed with the improvements of the present invention. This type of primer is in the form of a pump which includes a pump barrel or casing within which a piston is reciprocable. There is also provided a valve housing associated with the casin and a distributing valve is disposed within the valve housing. The valve housing has an inlet connection and one or more outlet connections Which are the end of its stroke whereby to permit rotation of the valve upon rotation of the piston in order to properly-position the valve for any selected point of distribution of the fluid. While the piston and valve are engaged, limited axial movement of the piston relative to the valve is permitted in order to effect locking of the piston and the valve in a position closing the outlet port or ports and preventing distribution of the fluid. In order to release the piston from this locked position, it is necessary to effect relative movement of the piston with respect to the valve and this movement of the piston includes an initial axial movement tending to compress any fluid which is trapped within the pump casing.

A primer of this type maybe conveniently used in various installations, as for instance, in airplane installations, Where fuel is withdrawn by the primer from a source of supply, preferably through a strainer, and then forced into the en.- gine for facilitating the starting thereof. The

primer may be installed with the inlet line connected to either the low or the high pressure side of the power fuel pump and it is, of course, desirable to install the primer so that a minimum movement of strokes of the piston is necessary in order to force fuel into the engine. Where the primer is mounted a substantial distance above the source of supply or strainer, the increased head will often cause some of the fluid to drain back so that a number of strokes of the piston are necessary before the inlet line to the primer is filled and the fuel forced to the engine. In order to overcome this difliculty, the primer is sometimes installed with the inlet line thereof connected to the pressure side of the power pump which pumps fuel under relatively low pressure (15 or 20 lbs. per sq. in). After an initial starting of the engine, the power pump will tend to force fuel into the primerinlet line and even when the primer is shut off, the power pump may continue to exert sufficient pressure on the primer inlet line so as to unseat the check valve in the inlet port. This action will result in the maintenance of this same pressure within the primer itself and when the engine and power pump are stopped, the pump casing will be full of fuel'which will be trapped therein by the check valve at the inlet port. Since it is necessary to force the piston axially in the direction of compression for releasing the locking means, this movement is often prevented because of the relative incompressibility of the fuel which is trapped within the pump casing. When this occurs, it is impossible to release the piston from its locked position and such a condition may also result when the primer is connected to the low pressure side of the power pump.

An object of the present'invention is to provide a primer of the above type which is constructed and arranged in such a manner as to permit sufficient movement of the piston under all conditions to release the piston from its locked position.

A further object of the invention is to provide a primer of the above type wherein means are provided for'permitting displacement of the fluid within the pump casing in order to permit the piston to be shifted away from its locked position.

A still further object of the invention is to provide a primer of the above type having a closed chamber which is compressible to permit displacement of the fluid within the pump casing in order to permit the piston to be released from its locked position.

The above and other objects of the invention member 24.

will in part be obvious and will be hereinafter more fully pointed out. 1

In the accompanying drawing:

Figure 1 is a longitudinal sectional view through the primer and showing the piston and valve in a position for pumping fluid therethrough.

Figure 2 is an enlarged fragmentary view, in longitudinal section, showing the position of the piston and its associated parts when released from its locked position.

Figure 3 is a reduced transverse sectional view through the inner end of the piston and casing.

Figure 4 is a detail sectional view showing the locking slot in the casing.

The construction and operation of the primer is substantially identical to the primer shown in the Parker aforesaid Patent No. 2,185,564 but a brief description will be included herein. Referring more in detail to the accompanying drawing, the pump casing II) is illustrated as including a flange portion II by which the primer may be secured to a suitable support, as for instance, the cowl of an airplane. The outer end of the casing I includes an outwardly offset sleeve portion I2 which is externally threaded and the opposite end of the casing is outwardly offset to provide an internal chamber I3. A valve housing I4 is illustrated as being integral with the casing but this housing may be formed separate therefrom, if so desired. The valve housing includes an inlet connection I5 and one or more outlet connections I6, I! through which the fuel may be distributed. The piston I8 is mounted within the pump barrel or casing with a close sliding fit and the outer end of the piston -may be provided with a handle I9. An annular cap 20 threadedly engages the skirt portion I2 on the casing and also engages a packing follower 2| which is adapted to compress the packing 22 in order to provide a fluid-tightseal.

,The valve housing. I4 is provided with a tapered seat in which is located a conical valve member 23 which is pressed against the seat by a spring 24 having the inner end thereof abutting against the valve member and having the outer end thereof bearing against an abutment The bottom of the valve housing is closed by a cap 25 which is provided with an aperture 26 therethrough. A diaphragm 21 extends across the aperture 26 within the cap 25 and is thus subject to atmospheric pressure.

The valve member is provided with a centrally located port 28 which is in communication with the chamber I3 and there is also provided a radial port 29 which is adapted to selectively register with outlet ports in communication with the outlet connections I6 or I1. The inner end of the port 28 is provided with a valve seat with which a ball check valve 36 is adapted to cooperate for controlling the passage of fluid. The ball 30 is yieldingly pressed against the seat by a plunger 3| which is recessed to house a spring 32 having the inner end thereof bearing against the plunger and having the outer end thereof bearing against the diaphragm 21. The inlet connection I5 is provided with a valve seat formed in the inner end of an annular insert 33 and a ball check valve 34 is adapted to cooperate therewith. A passage 35 afiords communication between the chamber I3 and the inlet connection I5.

The piston I8 is provided with a longitudinal recess 36 and the open end of the recess is closed by a plug '31 which is secured to the piston by a pin 38 or the like. A key 39 extends across the inner end of the piston and through a' slot in the plug 31 and is secured thereto by the pin 38. The wall of the pump casing I 0 is 5 provided with longitudinally extending recesses or keyways 40, 40a which are symmetrically positioned with respect to the outlet connection I6, I1 and with which a projection or looking lug M on the key 39 is adapted to cooperate.

Between the keyways 40, 400., there is provided a locking recess 42 into which the lug M is adapted to extend upon proper manipulation of the piston in order to lock the same. The extended end of the plug 31 is provided with an annular shoulder portion 43 and also with a slot into which a transversely extending projection or key 44 on the valve member is adapted to extend. This slot and key connection provide means whereby the valve member can be rotated upon rotation of the piston when the piston reaches the inner end of its stroke. A cup member 45 is mounted on the extended end of the plug 31 by means of an inwardly extending flange and the opposite end of the cup member is provided with an outwardly extending flange 46. A spring 4! surrounds the cup member and has one end thereof bearing on the flange 46 and the opposite end thereof bearing against the inner end of the piston. The spring and the cup member move with the piston during reciprocation thereof and the parts are so dimensioned that when the piston is moved inwardly during compression, the cup member will contact with the bottom wall of the chamber I3 and at this time, the extended end of the plug 31 becomes engaged with the key 44 on the valve member and further inward movement of the piston will compress the spring 41 and move the lug 4I out of the keyway in the side wall 40 of the pump casing. Thus, the keyways 40 or 40a are adapted to be aligned with the lug 4| so as to permit pumping reciprocation of the piston. When it is desired to turn the valve to an off position, the piston can be rotated so that the lug M will become aligned with the locking recess 42 and when pressure on the piston is released, the spring 41 will force the piston outwardly so that the piston or valve member Will be locked with the lug 44 engaged in the recess 42.

The plug 31 is provided with a relatively small aperture 48 therethrough and this aperture provides restricted communication between the chamber I3 and the recess 36. A compressible chamber is disposed in the recess 36 within the inner end of the plug 31. This compressible chamber is illustrated as including a tubular bag 49 having a flexible wall portion and the end of the bag is closed by a plug 50. The wall portion of the bag is secured in sealed relationship with the closing plug 50 by means of a clamping ring 5| or the like. The bag is filled with air or other fluid which is more compressible than the fuel or other fluid to be pumped by the primer.

- The compressible bag substantially fills the recess 36 in the piston I8 although it is illustrated as being slightly spaced from the walls thereof so that the fuel will gain access to the recess '36 through the restricted aperture 48.

In operation, the ,piston is forced inwardly so that the locking lug passes out of the locking recess 42 and the piston may then be turned into alignment with one of the keyways 40, 40a. As illustrated in Figure 1, the lug 4| is disposed in v the keyway 40 and the valve port 29 is in communication with the outlet line It. In this position of the parts, the piston can be manually reciprocated by means of the handle 19. On the outward suction stroke of the pistons I8, fuel will be drawn from the inlet line l past the check valve 34 and into the chamber l3 and the piston casing through the port 35. Upon inward movement of the piston l8, the check valve 34 will be closed and the ball check valve 30 will be opened so that fuel is forced through the port 39 into the outlet line I6 from which the fuel is directed to the desired location. During priming, any suction pull on the outlet connection from the engine will create a vacuum in the recessbeneath the plunger 3| by means of the port 3la therethrough. The diaphragm being subject to atmospheric pressure, will shift inwardly so as to increase the tension of the spring 32 and. thus tightly seat the ball check valve 311. After initial priming, the engine is started and the primer is turned to an off position, that is, the piston 18 is forced inwardly so as to withdraw the lug 4| from the recess 40 and the piston is then rotated so that the lug 4| can be positioned within the lock recess 42. In this locked position of the primer, the port 29 will be shifted with the valve member 23 so that it is out oi register with the outlet lines.

As previously indicated, the piston casing becomes completely filled with fuel so that a subsequent release of the locking means for the piston and valve is rendered difficult or impossible by reason of the fact that the piston must be moved inwardly in the direction of compres sion for releasing the lug 4[ from the locking recess 42. For instance, where the inlet line [5 is connected to the high pressure side of the power pump, continued operation of the power pump by the engine will tend to transmit the pressure of the power pump through the inlet line and against the check valve 34. When this pressure is sufficient to overcome the close tendency of the check valve 34, the pressure will be transmitted to the fluid filling the chamber [3 and the recess 36. Then, when the engine is stopped, the check valve 34 prevents release of this additional pressure so that it may be impossible to shift the piston l8 inwardly to release the locking device. However, the provision of the compressible chamber 49 permits the piston to be moved inwardly at least a suflicient distance to release the lug 4| from the locking recess 42. During this inward forcing of the piston, the compressible bag 49 will be forced inwardly in some manner, as shown in Figure 2,.

to compress the air therein and permit a corresponding displacement of the relatively incompressible fuel so as to facilitate unlocking of the piston and valve member.

From the foregoing description, it will be seen.

that the present invention provides an improved and highly eificient engine primer assembly wherein manual operation of the primer is greatly facilitated. Furthermore, the present invention provides a primer which can be manually operated under all conditions. Thus, the compressible air bag within the piston operates as a safety device to permit displacement of any trapped fluid in order to permit release of the piston and valve from locked position. The compressible fluid within the bag is such as to permit downward movement of the piston from a locked position by permitting the necessary displacement of fluid which is trapped within the casing.

While one form of the invention has been shown for purposes of illustration, it is to be clearly understood that various changes in the details of construction and arrangement of parts may be made without departing from the scope of the invention as set forth in the appended claims.

I claim:

1. A fluid dispensing device comprising a pump casing having a reciprocating piston therein, a distributing valve associated with the casing for controlling distribution of the fluid, means operable to" provide a releasable connection between the piston and the valve near the end of the compression stroke of the piston whereby rotation of the piston will effect rotation of the valve to different set positions, locking means for preventing rotation of the connected piston and valve from an inoperative position preventing distribution of fluid and said locking means being releasable upon initial movement of the piston in the direction of compression, and means providing a variable chamber associated with the dispensing device and responsive to displacement of fluid within the casing for permitting displacement of the fluid in the casing upon movement of the piston away from its locked position whereby to facilitate release of the locking means.

2. A fluid dispensing device comprising a pump casing having a, reciprocating piston therein, a distributing valve associated with the casing for controlling distribution of the fluid, means operable to provide a releasable connection between the piston and the valve near the end of the compression stroke of the piston whereby rotation of the piston will effect rotation of the valve to different set positions, locking means for preventing rotation of the connected piston and valve from an inoperative position preventing distribution of fluid and said locking means being releasable upon initial movement of the piston in the direction of compression, and means providing a closed compressible chamber located within the dispensing device and responsive to displacement of fluid therein for permitting displacement of the fluid in the casing upon movement of the piston away from its locked position whereby to facilitate release of the locking means.

3. A fluid dispensing device comprising a pump casing having a reciprocating piston therein, a distributing valve associated with the casing for controlling distribution of the fluid, means operable to provide a releasable connection between the piston and the valve near the end of the compression stroke of the piston whereby rotation of the piston will effect rotation of the valve to different set positions, locking means for preventing rotation of the connected piston and valve from an inoperative position prevent- 4. A fluid dispensing device comprising a pump casing having a reciprocating piston therein, a distributing valve associated with the casing for controlling distribution of the fluid, means operable to provide a releasable connection between the piston and the valve near the end of the compression stroke of the piston whereby rotation of the piston will effect rotation of the valve to different set positions, locking means for preventing rotation of the connected piston and valve from an inoperative position preventing distribution of fluid and said locking means being releasable upon initial movement of the piston in the direction of compression, said piston having an internal recess, means providing restricted communication between the recess and the casing whereby to permit fluid to gain access to the recess, and means providing a closed com pressible chamber located within the said recess and responsive to displacement of the fluid for permitting displacement of the fluid in the casing upon movement of the piston away from its locked position whereby to facilitate release ,of the locking means.

preventing rotation of the connected piston and valve from an inoperative position preventing distribution of the fluid and said locking means .being releasable upon initial movement of the piston in the direction of compression, means providing an internal recess within the piston and said recess being in communication with the pump casing, and means disposed within said recess and responsive to fluid pressure for per mitting displacement of the fluid in the casing upon movement of the piston away from its locked position whereby to facilitate release of the locking means.

6. A fluid dispensing device comprising a pump casing having a reciprocating piston therein, a distributing valve associated with the casing for controlling distribution of the fluid, means operable to provide a releasable connection between the piston and valve for effecting rotation of the valve to various set positions upon rotation of the piston but permitting reciprocation, of the piston independently of the valve, and means providing a variable chamber associated with the dispensing device and responsive to displacement of fluid within the casing for permitting displacement of the fluid and the piston toward a position for rotating the valve to predetermined set positions,

'7. A fluid dispensing device comprising a pump casing having a reciprocating piston therein, a distributing valve associated with the casing for controlling distribution of the fluid, means operable to provide a releasable connection between the piston and the valve near the end of the compression stroke of the piston whereby rotation of the piston will effect rotation of the valve to various set positions, locking means for pre- .piston away from its locked position whereby to facilitate release of the locking means.

8. A fluid dispensing device comprising a pump casing having a reciprocating piston therein, a valve housing associated with the casing and having a distributing valve therein for controlling distribution of the fluid, a check valve controlling the inlet to the valve housing and permitting admission of fluid on the suction stroke of the piston but preventing discharge of the fluid through the inlet on the compression stroke of the piston, means operable to provide a releasable connection between the piston and the valve near the end of the compression stroke of the piston whereby rotation of the piston will effect rotation of the valve to different set positions, locking means for preventing rotation of the connected piston and valve from an inoperative position preventing distribution of fluid and said locking means being releasable upon initial movement of the piston in the direction of compression, and means providing a variable chamber associated with the dispensing device and operable in the event that the fluid is under sufficiently high pressure to fill the casing by opening the check valve at the inlet to the valve housing for permitting limited displacement of the fluid in the casing upon movement of the piston away from its locked position whereby to facilitate release of the locking means.

9. A fluid dispensing device comprising a pump casing having a reciprocating piston therein, a distributing valve associated with the casing for controlling distribution of the fluid, means operable to provide a releasable connection between the piston and the valve near the end of the compression stroke of the piston whereby rotation of the piston-will effect rotation of the valve to various set positions, locking means for preventing rotation of the connected piston and valve from an inoperative position preventing distribution of fluid and said locking means being releasable upon initial movement of the piston in the direction of compression, and means disposed within the piston and providing a variable chamber connected with the dispensing device and operable in the event that the casing is filled with fluid to permit limited displacement of the fluid upon movement of the piston away from its locked position whereby to facilitate release of the lockmg means.

- ARTHUR L. PARKER.