GB1596104A

GB1596104A - Vacuum pump

Info

Publication number: GB1596104A
Application number: GB6364/78A
Authority: GB
Original assignee: Barmag Barmer Maschinenfabrik AG
Current assignee: Oerlikon Barmag AG
Priority date: 1977-02-17
Filing date: 1978-02-17
Publication date: 1981-08-19
Also published as: FR2381191B3; JPS53117809A; IT1105298B; DE7704803U1; FR2381191A1; IT7847993A0

Description

(54) VACUUM PUMP (71) We, BARMAG BARMER MASCHINENFABRIK AKTIENGESELL SCHAFT, a body corporate, organised under the laws of the Federal Republic of Germany, of Remscheid-Lennep, Federal Republic of Germany, do hereby declare the invention, for which we pray that a patent may be granted to us, and the method by which it is to be performed, to be particularly described in and by the following statement: The invention relates to a vacuum pump, in particular a vane pump, for brake power assistance units in motor vehicles wherein the vacuum pump is driven by the combustion engine, in particular a diesel engine, of the motor vehicle and wherein a flange is arranged on the vacuum pump housing for fixing the vacuum pump to the housing of the motor vehicle engine.

Such vacuum vane pumps are provided with lubricating oil from the central engine lubricating system for lubricating and sealing the vaccum pumps. In particular, those vaccum pumps which are driven by means of V-belts or other drive belts by the motor vehicle engine, i.e. not directly by the engine drive shaft or by engine intermediate shafts, are also connected to the lubrication system of the motor-vehicle engine via a compressed oil pipe. The spent lubricating oil is usually recycled together with the exhaust air via an outlet pipe into the housing of the combustion engine. Rigid pipes or flexible tubes are generally used for this purpose.

One disadvantage of the pipes and tubes is that they are very bulky in the relatively narrow engine chamber of the motor vehicle and therefore obstruct servicing of the motor. Assembly and dismantling particularly of the pipes is time-consuming. Furthermore, the use of tubes as connecting elements introduces an inherent uncertainty into the situation because they may be damaged very easily and easily become detached from their connection nozzles as a result of vibration in normal operation if complex safety devices are not provided. In addition, they may be detached from the connection nozzles inadvertently and unnoticed during servicing.

An object of the invention is to provide a vacuum pump which is such that it may be assembled and dismantled rapidly and easily even in restricted engine chambers of the motor-vehicle, the pipe connections with the engine housing requiring little or no servicing, being protected from external tampering and being such as not to obstruct servicing of the engine.

According to the invention there is provided a vacuum pump for a brake power assistance unit in a motor vehicle wherein the vacuum pump is drivable by an internal combustion engine of the motor vehicle, and in which pump a flanged base is arranged on the vacuum pump housing for fixing the vacuum pump to a housing of the motor vehicle engine, the base containing a lubricant feed duct for feeding lubricant to the interior of the vacuum pump and an air and oil outlet duct each of the said ducts opening in a flat surface of the base, which surface abuts the housing of the said engine when the pump is in situ and extends on to the flange(s) of the base, the said flat surface being designed as a sealing surface for the said ducts.

With such a pump, all tube or pipe connections between pump and engine may be dispensed with. The connections for the exhaust air as well as for the inflowing and issuing oil are produced at the same time by flanging the pump on to the engine housing. This represents not only advantageous use of space but also a considerable saving both in material and in working time.

Because the flat surface of the base is designed as a sealing surface for the exhaust air and oil ducts, the danger of leakage points being formed is reduced to a minimum. The attachments may optionally also be sealed off with O-rings in the flat surface of the base.

Depending upon the space available, it may be advantageous for the flat surface of the base to be arranged parallel to the pump shaft.

An embodiment of the vacuum pump accord ing to the invention is shown in the accompanying drawings, in which: Fig. 1 shows a vacuum pump connected by a flanged base to the engine housing of a motor vehicle; and Fig. 2 shows a plan of the flat surface of the base taken on section line II--II in Fig. 1.

As shown in Fig. 1, a rotary vacuum pump 1 of the sliding-vane type is flanged on a housing 4 of a motor vehicle engine by means of a flanged base 2 and bolts 3. An oil inlet duct 5 coming from the central lubrication system of the motor vehicle engine and represented by broken lines enters the vacuum pump 1 on the face of the pump housing.

Spent oil and the exhaust air from the vacuum pump are recycled into the engine housing 4 via a duct 6 also shown by broken lines.

The vacuum pump 1 sucks the air from the brake power assistance unit (not shown) via a connection 7.

The vacuum pump, which may, for example, be a vane pump, is driven by the motor vehicle engine via V-belt pulleys 8, 9 and a V-belt (not shown).

Figure 2 shows the openings of the oil inlet duct 5 as well as the exhaust air and oil outlet duct 6 in the flat surface of the flange base 2.

The flange connection may be centered by means of alignment pins or by centering bands (not shown) on the duct openings. Concentric grooves may optionally be worked in the flat surface of the base towards the duct openings and these grooves may receive O-rings for sealing the connections in the flat surface of the base.

A particularly compact sttucture of the vacuum pump with its connecting ducts may be obtained by so locating the ducts 5 and 6 that they extend through ribs of the vacuum pump housing into the flanged base and open in the flat surface of the base.

WHAT WE CLAIM IS:- 1. A vacuum pump for a brake power assist ance unit in a motor vehicle wherein the vacuum pump is drivable by an internal com bustion engine of the motor vehicle, and in which pump a flanged base is arranged on the vacuum pump housing for fixing the vacuum pump to a housing of the motor vehicle engine, the base containing a lubricant feed duct for feeding lubricant to the interior of the vacuum pump and an air and oil outlet duct, each of the said ducts opening in a flat surface of the base, which surface abuts the housing of the said engine when the pump is in situ and extends on to the flange(s) of the base, the said flat surface being designed as a sealing surface for the said ducts.

2. A vacuum pump according to Claim 1, wherein the connections in the said flat surface of the base are sealed with O-rings.

3. A vacuum pump according to either preceding claim wherein the said flat surface of the base is arranged parallel to the pump shaft.

4. A vacuum pump according to any preceding claim, which is in the form of a vane pump.

5. A vacuum pump substantially as herein described with reference to the accompanying drawings.

**WARNING** end of DESC field may overlap start of CLMS **.

Claims

**WARNING** start of CLMS field may overlap end of DESC **. ing to the invention is shown in the accompanying drawings, in which: Fig. 1 shows a vacuum pump connected by a flanged base to the engine housing of a motor vehicle; and Fig. 2 shows a plan of the flat surface of the base taken on section line II--II in Fig. 1. As shown in Fig. 1, a rotary vacuum pump 1 of the sliding-vane type is flanged on a housing 4 of a motor vehicle engine by means of a flanged base 2 and bolts 3. An oil inlet duct 5 coming from the central lubrication system of the motor vehicle engine and represented by broken lines enters the vacuum pump 1 on the face of the pump housing. Spent oil and the exhaust air from the vacuum pump are recycled into the engine housing 4 via a duct 6 also shown by broken lines. The vacuum pump 1 sucks the air from the brake power assistance unit (not shown) via a connection 7. The vacuum pump, which may, for example, be a vane pump, is driven by the motor vehicle engine via V-belt pulleys 8, 9 and a V-belt (not shown). Figure 2 shows the openings of the oil inlet duct 5 as well as the exhaust air and oil outlet duct 6 in the flat surface of the flange base 2. The flange connection may be centered by means of alignment pins or by centering bands (not shown) on the duct openings. Concentric grooves may optionally be worked in the flat surface of the base towards the duct openings and these grooves may receive O-rings for sealing the connections in the flat surface of the base. A particularly compact sttucture of the vacuum pump with its connecting ducts may be obtained by so locating the ducts 5 and 6 that they extend through ribs of the vacuum pump housing into the flanged base and open in the flat surface of the base. WHAT WE CLAIM IS:-

1. A vacuum pump for a brake power assist ance unit in a motor vehicle wherein the vacuum pump is drivable by an internal com bustion engine of the motor vehicle, and in which pump a flanged base is arranged on the vacuum pump housing for fixing the vacuum pump to a housing of the motor vehicle engine, the base containing a lubricant feed duct for feeding lubricant to the interior of the vacuum pump and an air and oil outlet duct, each of the said ducts opening in a flat surface of the base, which surface abuts the housing of the said engine when the pump is in situ and extends on to the flange(s) of the base, the said flat surface being designed as a sealing surface for the said ducts.