US3435778A

US3435778A - Adapter for mounting hydraulic pump

Info

Publication number: US3435778A
Application number: US660708A
Authority: US
Inventors: Anthony L Ascuitto; Vito J Romani
Original assignee: NATIONAL PUMP AND INJECTOR SALES AND SERVICE
Current assignee: NATIONAL PUMP AND INJECTOR SALES AND SERVICE
Priority date: 1967-08-15
Filing date: 1967-08-15
Publication date: 1969-04-01
Anticipated expiration: 1986-04-01

Description

April 1, 1,969 A. ASCUITTO ET l. 3, I ADAPTER FOR MOUNTING HYDRAULIC PUMP' Filed Au 15, 1967 Viz-a 20014111 United States Patent US. Cl. 103218 4 Claims ABSTRACT OF THE DISCLOSURE An improved mounting bracket is described herein, which is used for mounting an hydraulic starting pump on the housing of a marine diesel engine, and to permit an auxiliary drive shaft in the engine to be directly coupled to the actuating shaft of the pump.

Background 0f the invention It has been usual in the past to start the smaller diesel marine engines by means of a usual electric starter. For this purpose, one of the auxiliary drive shafts such as the balnece shaft in the diesel engine has usually been used to drive a pulley which, in turn, is coupled by a belt to an electric generator in the electric starter circuitry. The electric generator maintains a charge on the storage battery which, in turn, is used to energize the electric starter.

In recent years, it has been found more expedient to use compressed air for starting such marine diesel engines. For that reason, the aforesaid generator has been replaced by an hydraulic pump. The purpose of the pump is to pump hydraulic fluid into a accumulator, and thereby build up air pressure in the accumulator. When the air pressure in the accumulator drops below a selected threshold, for example, during starting of the diesel engine, the pump retains the air pressure to the desired level, after the engine has started and drives the pump. A simple bypass is provided for the hydraulic fluid after the selected air pressure has been reestablished in the accumulator, all in a manner well understood in the art.

Problems have been encountered, however, when it was attempted to couple the aforesaid hydraulic pump to the diesel engine balance shaft. The balance shaft in one common type of diesel engine, for example, terminates inside the engine housing in a relatively large rotatable flange. In order to drive the generator in the eariler installations using electric starters, another flange was coupled to the aforementioned flange in facing coaxial relationship, and the latter flange was provided with a short stub extension shaft.

The stub extension shaft extended along the axis of rotation of the balance shaft and out the end of the engine. The aforesaid pulley was mounted on the stub shaft, originally to drive the generator in the earlier electric starter system. It was the practice in the past, when the electric starter was replaced by an hydraulic pump compressed air starting system, to drive the hydraulic pump by means of a belt drive from the pulley on the stub extension shaft. This proved to be somewhat unsatisfactory due to slippage and installation complications. Therefore, attempts have been made in the past to direct-couple the stub shaft to the hydraulic pump. However, even these latter direct couplings in the past have invloved complications and have proven to be generally unsatisfactory. Moreover, the previously used direct couplings often result in the leakage hydraulic fluid from the pump entering the engine housing and being mixed with the engine oil to form a harmful mixture within the engine.

3,435,778 Patented Apr. 1, 1969 Summary of the invention The present invention provides an improved and simple coupling and adapter bracket, whereby the hydraulic pump for the compresed air starting system may be rigidly and securely mounted on the housing of the diesel engine, and whereby the pump may be directcoupled to the balance shaft of the engine without the need for flexible couplings, or the like. Moreover, the improved coupling and adapter bracket of the invention is such that there is no tendency for any leakage hydraulic fluid from the pump to enter the housing of the engine.

Brief description of the drawings FIGURE 1 is a side sectional view showing the bracket of the invention mounted in place on the end of a diesel engine; and

FIGURE 2 is an end view of the bracket, taken essentially along the line 22 of FIGURE 1.

Description of one embodiment of the invention Only those portions of the diesel engine which are significant in explaining the improved coupling bracket of the invention have been shown in FIGURE 1. As described above, the diesel engine has a housing 10. The housing, in turn, has an opening 12 at one end which normally is covered by an appropriate cover plate.

It is usual in the marine diesel engine to incorporate auxiliary crankshafts on either side of the main crankshaft. One of these crankshafts, as mentioned above, is designated the balance shaft, and has been used in the past to drive the electric generator in the electric starting system of the installation. A portion of the balance shaft of the engine is designated 14 in FIGURE 1. It will be understood, of course, that the balance shaft 14 is rotatably driven when the engine is operating.

A flange 14a is mounted at the end of the balance shaft 14, and this flange rotates coaxially with the balance shaft. A second flange 16 is secured to the flange 14a, for example, by means of bolts 18. The flange 16 is coupled to the flange 14a in facing relationship, as shown in FIGURE 1. A 'stub shaft 20 is formed integral with the flange 1'6, and when the flange 16 is coupled to the flange 14a, as shown in FIGURE 1, the stub shaft 20 is precisely positioned for rotation about the axis of rotation of the balance shaft 14.

As explained above, in the previous asemblies, a cover plate was provided across the opening 12 in the end of the engine housing 10, and the stub shaft 20 extended through an opening in the cover plate. Appropriate oil seals were provided to seal the stub shaft 20 to the cover plate. In the practice of the present invention, the cover plate is removed, and the cover plate is replaced by an adapter mounting and coupling bracket 22 constructed in accordance with the concepts of the present invention.

The adapter bracket 22 includes a central hollow bosslike body portion 22a which receives the stub shaft 20. The bracket also includes a first flange 22b which is formed integral with the body portion 22a at the left hand end of the body portion. The flange 22b is mounted on the engine housing 10 by means, for example, of appropriate bolts 24. The bolts 24 may be the same bolts which previously held the cover plate on the housing in the prior art installation.

A counterbore 26 is provided at the left hand end of the boss-like 'body portion 22a adjacent the flange portion 22b. The counterbore 26 receives, for example, a flexible oil seal 27 which may be composed, for example, of rawhide, or the like. The seal 27 serves effectively to seal the stub shaft 20 to the adapter bracket 22.

A second flange 22c is formed integral with the right hand end of the boss-like body portion 22a. An hydraulic 3 pump 28 is mounted on the flange 220 by means, for example, of appropriate bolts 30. The bolts 30 extend through a flange 32 on the pump and through the flange portion 220 of the adapter bracket 22.

The pump 28 has an actuating shaft 34, and when the pump is mounted in position, as illustrated in FIGURE 1, the shaft 34 extends into the body portion 22a of the adapter bracket, in axial relationship with the stub shaft 20, and into the stub shaft, as shown, the stub shaft having a hollow tubular configuration so as to receive the actuating shaft 34. The tubular stub shaft is provided with an internal longitudinal keyway which receives a key 36. The key 36 is coupled to the actuating shaft 34 of the pump, so that the stub shaft 20 may drive the actuating shaft 34.

It will be appreciated that any hydraulic fluid which may leak from the pump 28 into the interior of the bracket 22 has no tendency to flow into the engine housing 10 in the illustrated assembly of FIGURE 1. A drain 38 is provided in the boss-like body portion 22a of the coupling bracket, and this drain extends radially through the wall of the body portion. An appropriate conduit may be coupled to the drain 38, so as to convey any hydraulic fluid which may enter into the body portion 22a back to the sump of the pump 28.

It will be appreciated that the improved adapter bracket of the invention rigidly and securely mounts the pump 28 on the end of the engine housing 10. The mounting of the pump by the bracket is positive and secure, with the actuating shaft 34 of the pump being precisely aligned with the stub shaft 20, such that no flexible coupling is required in order for the balance shaft 14 to drive the pump 28.

Any hydraulic fluid which may leak from the pump 28 into the boss-like body portion 22a of the adapter bracket passes down through the drain 38 and back to the sump of the pump. In this way, three is no tendency for the hydraulic fluid to enter the engine housing and form a harmful mixture with lubricating oil in the diesel engine itself.

As described above, the hydraulic pump 28 pumps hydraulic fluid into an accumulator in order to build up air presure in the accumulator. When a selected air pressure has been reached, and in a manner known to the art, an automatic bypass opens up and unloads the pump. However, whenever the pressure drops in the accumulator, the pump automatically acts to return it to the original selected pressure.

The improved mounting bracket of the invention provides, therefore, a simple and rugged one-piece mounting means for the pump, whereby the actuating shaft of the pump is precisely and accurately aligned with the stub shaft for a positive and direct-coupling between the stub shaft and the pump. The bracket of the invention is simple to mount, in that in many applications it merely replaced the cover plate originally mounted on the engine.

While a particular embodiment of the invention has been described, it is clear that modifications may be made. It is intended, therefore, in the claims to cover all modifications which come within the scope of the invention.

What is claimed is:

1. An adapter bracket for mounting a pump on the end of an engine, said engine having a rotatable stub shaft coupled to a drive shaft therein, and said pump having an actuating drive shaft, said adapter bracket comprising:

a hollow boss-like body portion;

a first flange at one end of said boss-like body portion and configured to be mounted on the end of the engine with said hollow body portion coaxial with the axis of rotation of said stub shaft and with said stub shaft extending into said body portion; and

a second flange at the other end of said boss-like body portion and configured to have the pump mounted thereon in position so that said actuating drive shaft of the pump extends into said hollow boss-like body portion in coaxial relationship with said stub shaft and into keyed relationship with said stub shaft.

2. The adapter bracket defined in claim 1, in which said first and second flanges are integral with said bosslike body portion.

3. The adapter bracket defined in claim 1 and which includes a counterbored section at one end of said body portion adjacent said first flange for receiving a seal effective to seal said stub shaft to the adapter bracket.

4. The adapter bracket defined in claim 2 and which includes a drain for hydraulic leakage fluid from the pump, said drain being formed radially in said body portion and extending through the wall thereof.

References Cited UNITED STATES PATENTS ROBERT M. WALKER, Primary Examiner.

US. Cl. X.R.