DE1528395A1 - Fuel pump - Google Patents

Description

New documents for the

PATENT Attorneys 1 ζ 9 R ^ Q R

dr. ing. H. NEGENDANK · di.pl.ing. H. HAUCK ■ Dipl.-Phys. W. SCHMITZ ^

HAMBURG- MÜNCHEN DELIVERY ADDRESS: HAMBURG 36 NEW WALL 41

TKI .. 36 74 38 AND 36 4118

P 15 28 395 »1 TJLIGR. NKGIDIFITINT IiHBVlO

Borg-Warner Oorp. Münchenia mozartstrasse 23

TEL.5380086

TELBGH. NKGEDAFATENT MUNICH

Hamburg, April 15, 1969

Fuel pump "

The invention relates to a fuel pump, in particular for pumping fuel from a tank a fuel injection system with a variable stroke pump tappet and one with a drive shaft connected, the tappet by means of a drive cam driving the crankshaft.

Fuel pumps of the type mentioned are known. However, they have the disadvantage that they during their operation develop annoying noises. These noises within the pump are often caused by the periodic Separation of the drive member caused by the Purapen plunger.

It is the object of the invention to create a fuel pump in which disruptive noise is generated

009027/0255 * original bathroom

. '■■ ..- 2 possibility are avoided.

The task at hand is with a fuel pump a pump plunger of variable stroke and a connected to a drive shaft, the plunger by means of a Drive cam driving crankshaft solved in that according to the invention on the cam part of the crankshaft a sleeve is mounted and a loading member acting on the sleeve continuously attaches the sleeve to the plunger Nooke nteil brings to the plant and that between the sleeve and the end of the ram facing it has an elastic member aijaeordered.

The loading member thus always presses the sleeve from the same side, namely from the tappet against the cam part the crankshaft. During the rotation of the cam part cannot do this periodically as a result of its Unbalance the sleeve as far as the bearing clearance allows, push back and forth. A noise development between the Sleeve and the cam part is avoided. Another source of noise was the connection between the sleeve " and the plunger, due to the fact that the end of the plunger is now elastic, for which purpose an elastic member is used, which has a noise-dampening effect is also part of this connection, at which a periodic contact takes place, the development of noise largely suppressed.

009827/0255

Bach is an expedient embodiment of the invention in addition to the elastic member and the loading member in the drive shaft or S.tb'ßelzug, an elastic connecting member between the drive shaft and the crankshaft "is provided. This elastic connecting member, that couples the two shafts mutual twisting of the crankshaft and drive shaft, This means that the different moments of inertia between the motor and the drive shaft are on the one hand and On the other hand, the crankshaft is better balanced during operation and the phase shift is reversed the direction of movement of the pump plunger increased "

According to an expedient embodiment of the invention, the loading element consists of a FscIdeo 3s irasü, 1- ;; ^r I-> ch also be designed as a connecting rod comprising the sleeve, which by means of a vacuum pump, the sleeve of the plunger viegzieben * Both loading members work. reiofiettix elastic «, ura a permanent zLoiraafc ^ swisehen '3 sleeve and aera 17oei: en1,; eil sufreost zn -5I ⁵ ^ aϊΐen,

als LelsstuiagrigXiii'l 'V) Sw Feder beutsw!;, ΊύΏη exist

v9rlas? .fv -. "- id ^ n Br: ick; isaGr ¹ U ₁ ,

? -it '-.?. - liian' * ye r *:>"t; ^Kisii?

the sleeve ^ - such «

009827/025 &

BATH

The spring arrangement has a particularly varied effect on the sleeve.

The fuel pump according to the invention, which in particular can be used advantageously in automobile construction, works largely noiseless, although like other conventional fuel pumps they operate at practically constant pressure has a variable delivery rate.

The invention is explained in more detail with reference to the exemplary embodiments shown in the drawing.

Fig «1 a longitudinal section of the« rei ^ wE ^^ ra-ets' pump of the vor lying invention!

Figo 2 is a view taken along 2-2 of Mnie Fxg * 1 ° _s 3 is a view taken along line 3 = 3 · the Figo 2 _S ° and

Figo 4 shows a modification of the pump from Figo 2 _S containing a drive for a Takirampu.mpe

fcs designations beaeicbneti same part © xo den voz ^ view en ₀

To ilen geicbnisns-Pß wircl aie rumtie äev Toriie ^^ nu ^ v-

^BATH

dung generally represented and encompassed by the Hummer 10 Eitien drive part 11, a pump part 12 and a Steam separation part 13.

The drive part 11 consists of an electric drive motor 14 with a drive shaft 15 and an eccentric camshaft 16, which by means of the resilient Coupling 17 is connected to the drive shaft 15. The camshaft 16 is supported by a plurality of bearings 19 stored within the housing 18. The housing 18 is connected to the housing by means of a plurality of bolts 21 10 connected for the electric motor 14. The camshaft 16 extends into a cavity 22y within the Housing 18 is formed and carries a sleeve 23 which is mounted on one end of the camshaft 16 by means of a bearing 24 is stored.

It is thought that the electric motor 14 is a Doppelschlussmp.tor which runs at substantially constant speed under various conditions and a high Has tightening torque.

The pump part 12 consists of the housing 30 with the stepped cylindrical longitudinal bore 31 and a pump plunger 32, which moves back and forth in the bore 31.

- 6 Ö09827 / Ö25 & ^ -.-.

'BAD ORIGINAL

• -6 - ·

The pump tappet 32 carries a spring retainer 33 which connected by the screw 34 at one end. The screw 34 carries a rubber part 35 »which contacts the drive sleeve 23 on the camshaft 16. Sine spring 36 is pressed together in a recess 37 in the housing 30 and presses the spring retainer 33 The spring 36 urges the piston 32 to the left as shown during part of a pumping stroke. One Spring 38 to cancel the bearing play is also stored within the housing 18 in the recess 22 and presses against the drive sleeve 23 »The spring 38 is preferably made from a continuous piece of spring material in a generally U-shaped arrangement bent and rests against the sleeve 23 so that the Sleeve 23 and camshaft 16 to the left as shown are pressed, whereby play in the camps 19 and 24 is absorbed.

The pump plunger 32 is cylindrical with an enlarged Head frame 39 is provided, which extends into an enlarged part of the borehole 31. The headpiece 39 separates the enlarged part of the borehole in two pumping chambers n, be ze idinet as 31a and 31b. Of the outer diameter of the cavity 31a is preferably twice as large as the borehole 31 'through which it extends

- 7 -
the pump plunger 32 extends.

The head 39 of the plunger 32 did with a detached cylindrical borehole 40 and a Mngskanal 41 provided which the borehole 40 with the inner chamber 31a connects. A spring loaded discharge valve 42. is held in the borehole 40 by an end cap 43 fixedly connected to the head 39. The cap 43 has a central opening 44j which extends towards Kaimner 31b opens, 3 a circular spring as an inlet valve 45 is opposite the chamber 31b and regulates the flow of fuel from fuel inlet 46. Chamber 31a is through the outlet opening 47 with a Yersorgmigsanlage of fuel for a burn raaschiae (not shown) tied together.

The steam cleaning part 13 reads from etDem ώχϊ ö; em - housing "30 firmly connected housing 50 with elaein inner hobli-auiii 51 ■■, - sieer lialg ₅ 4 & aaif & iTnebm ^^ s siosca WiSo ^ staBüsteil 553 _ΰ ύίϊΐ ^ Έ. AuslaSöff ^ uüg.5- aim ^ i ^ es Iiatspfsii ^ eiG ^ soffeiaog: ^ 5 » the

tf-eats He; ^ aetofftai · ^ 5i "- vvlvsiiüen, -I ' " - ^ opening

dos 2 \ Xu: vrQf: u-2; il- \ '■: i. "■" :: ■:; / ■> ■, -. T; Ö- ^ a> - " , sii, the ■

- 8th -

G; '. & c / 7/0 ^{2 f} : B - _{BAD ORIGINAL}

- 8 pump 10 also to be attached inside the tank 56.

The vapor equalization opening 55 opens into a grooved chamber 57 which is connected to the uppermost part of the fuel tank 56 via a connection 58. A float 59 is located in the chamber 57 and closes it against the opening 55. The float 59 is centered in the chamber 57 by grooves 60 in the side walls and is prevented by drivers 61 at one end of the connecting tube 58 from moving the Block outflow pipe 58. The float 59 is set so that it closes the opening 55 when the fuel level in the tank is insufficient! in order to lift the float 59 from the opening 55, z, B _o -v © nn the vehicle with little fuel in the tank is on an incline Connection pipe 58 into chamber 51 "

In operation the fuel is normally © red arrive by gravity from the tank 56 through the Invitation 46 to the cavity 51 ", the motor 14 is turned on j, offset, shaft 15 and 16 die.Hockenwelle Io rotation and moved (3.ΘΏ PumpeastÖßel 32 IrLn and her * WatesBä siaes rope of its lift is fuel öurcb the Eialafö "? @ Iriril

00 & 827/0255

45 sucked into the chamber 51b. The camshaft 16 rotates see further, the plunger 32 is forced to the right and compresses the fuel in the chamber 31b. The inlet valve 45 closes and the fuel in the chamber 31b is pushed through the outlet valve 42 and the channel 41 into the chamber 31a. During the rest During the pumping process, the spring 36 forces the plunger 32 to the left, whereby the "valve 42 closes and the Fuel is forced out of chamber 31a through outlet port 47. ■

It should be noted that the pump portion 12 performs a dual function Inlet valve 45 is sucked into chamber 31b at the same time fuel is pressed from chamber 31a through outlet valve 47 when the ram 32 is closed moved to the left. The same is done during the sealing process Fuel compressed within chamber 31b. Half of that displaced from chamber 31b Fuel fills the chamber 31a, the other half is due to the cross-sectional difference between Head 39 UAd the main part of the plunger 32 through the outlet port 47 forced.

The fuel pressure at the outlet port 47 is in

- 10 - 00 9827/02 5 S bad original

- ΊΟ - · ■ - ■■ ..

essentially determined by the strength of each 36 who The amount of fuel delivered is determined by the longitudinal displacement of the pump tappet during each work cycle 32 'determined.

In order for the pump part 12 to work properly ensure that fuel vapors from the fuel supplied to the pump chamber 311: can be separated. The resistance part 53 acts as a barrier to to separate the bubbles formed within the fuel from the heavier, liquid part of the fuel. The pump normally works in the position shown and bubbles go through opening 55 on float 59 over, through pipe 58 back to tank 56. The liquid Part of the fuel passes through inlet valve 45 into chamber 31b. As already described, the valve seals 5.9 the inlet 55 against the ingress of air or Steam from the feed pipe 58 into the inlet valve 4-5, when there is insufficient fuel in the tank 56 1st to make the swimmer 59 swim or if the vehicle happens to be on an incline with a nearly empty tank. It is important, that the steam at a point directly at the fluid inlet port to the pumping chamber is separated to prevent the re-formation of bubbles in the liquid just before the

- 11 -

0098277025g

Avoid entering the pump.

As already described, the hat) of the pump tappet 32 is variable and depends on the fuel requirements of the internal combustion engines to be supplied. The spring 56 determines the nominal working pressure of the liquid to be delivered. The pressure exerted by the leather is determined by the pressure of the liquid against the head 39 and the body of the plunger 3? balanced. During normal operation, the backward movement of the tumbler ram 32 is therefore limited by the fluid pressure. A limited backward movement of the plunger 32 brings about a periodic contact between the drive sleeve 23 and the rubber part 35 _f which is attached to the end of the plunger 32. It has been shown that this periodic contact causes undesirable noises »

The intensity of these sounds is due to the. the following measures have been reduced to a minimum = (a) The attachment of a (xU:? itin.buffer 35 causes a vjäLche-n contact between'the drive sleeve 23 and the tappet 32, · (b) The flexible FupplüBg 17 '- rftx-minäert the impact between the sleeve S3 mod the Eappe 3S ₂ iüdem she BrshDe swi.sclien der Hockt jwelle 16 uoäer JiQ'fcjSie'öswelle 15 equips _s dsbei äis wisksaas fs "ä ^ ieit dfi-s i-iöt ^ ra

009827 / O25R 1 ^

Original

decreases and increases the phase shift until the direction of movement of the pump plunger 32 is reversed; and (c) The spring 38 always pushes the sleeve 23 and the camshaft 16 to the left, as indicated in the drawing is. The spring 38 acts against the unbalanced forces created by the camshaft 16 and the eccentric sleeve 23 mounted thereon arise, counteracting and thus essentially preventing radial movement or bearing play of the eccentric shaft 16 and the sleeve 23, which at the time of contact in the bearings 19 and 24 can occur.

In Fig. 4 a modification of the pump of Fig. 2 is shown, which includes a vacuum pump 70 driven by motor 14.

The vacuum pump 70 comprises a housing 71 which is connected to the housing 18 and having a cylindrical longitudinal bore 72 in which a piston is slidably mounted 73rd The bore 72 is intended to be closed at one end by a flap valve 74 which is held in position by an end cap 75. The cap 75 is screwed onto the housing 71 and had a neck-like portion 76 and a cylindrical bore 77 along its length. The tale-like part 76 canoe

00 9827/025 5

■■ - 13 -

Pick up flexible pipe or pipeline that is connected to a vacuum reference control for the fuel injection system with which the pump 10 is used target.

The piston 73 reciprocates in the bore 72 and is Connected to the sleeve 23 via a connecting rod? 8. The piston 73 has an annular recess 79, .die a unilateral sealing ring 80 carries. That Housing 71 has an annular groove 81 aif around the Piston 73 goes around and has a radial air vent 82.

During operation, the vacuum pump 70 works as follows: The switched-on motor 14 rotates, the camshaft 16 and the sleeve 23. The camshaft 16 causes the piston 73 reciprocates in the borehole 72. While moving down or when the piston 73 moves to the right as shown in the drawing, is through the inlet valve 74 air is sucked into the bore 72. During a compression cycle, so when the piston 73 to the left goes, the valve 74 closes and the air inside the bore 72 is compressed. Part of the hole 72 compressed air is forced past the sealing ring 80 and exits through the outlet opening 82.

0 9 8 2 7/0256 bad original

The sealing ring 80 has the shape of a lying Y ¹ S in cross section and acts in one direction, ie it allows air to pass through during the sealing process, but prevents air from flowing back during the suction process.

In the in Pig. 4, the spring 38 can be omitted. As soon as a partial yakuum in the Bore 77 is reached, a total force acts against the piston 73 and moves it to the left. This total force takes away radial movement or bearing play attributable to bearings 19 and 24. The vacuum pump 70 therefore fulfills the same function as the spring 38 by reducing the part of the noise which is due to bearing play development avoids.

This invention provides an improved fuel pump that operates at substantially constant pressure gives a variable delivery rate and is of appropriate size and cost for use in automotive engineering is.

The pump of the present invention effectively eliminates the noises due to the variable stroke of the plunger.

- 15 01) 9827/0265

It should be pointed out that this invention is not to be restricted to this particular constriction and to the embodiments shown and "described, at most to the extent that the claims are thereby" restricted. 2s is for the specialist without further? be seen since ¹ ? Jumps can be made without deviating from the principles of this original invention.

BATH ORIGINAL 009827/0756

Claims (1)

t e η ΐ ο η s ρ γ ii c b . ? Ι ^: Ρ: ΐη ^ ΐθί'ίpUTIlO ⁰ j * yiPbeSOnderCi ¹ "Vr" ^ Öri f ^ Oll ¹ "" VOYl Brenn— ^ toff «ι ¹ « a ^ nI: to a Brsnn ^ toffoinr.pr: ΐ ^ .η-l'-t ^ n, with oinom rumpenstoß "> variable strokes and an η-it a drive stage connected, don Ct ^ PeI medium ?? ^ ins ^ *? Itζ? ^ ObRnoci ^ on ¹⁷ "" ^ ntroiiosna ^ n Furbel ^T .7e "'."'. E, raw marked, ei. ^ I? On the woc> enteil 3er el '. * ^! · 1 *? (1 ^) eit: e H ¹ Ul? e (° ^) stored i ^ t and e "^; n fjuf die H'il ^ o ¹ ^ "* Γ"., ^! " ^ϊ ""!" ^ nd " ⁰ ""OZ ^^ O ^ nnpnde— Bf ^a ") ar! t '.' iV2 ^r "- ^c " 3tö3el (3?) Brings to the fctetiteil rrur attachment and d9.P sv; i. ° chen der Hu] ^ e and the. °. ^ rennstoffp-unpe mch claim 1, characterized in that !? According to the elastic oil member (35) and the prestressing load member (38, 78) in the drive shaft or tappet train, an elastic connecting member (17) is provided between the drive shaft and the crankshaft. 3. Fuel pump according to claims 1 and 2, characterized in that the loading member consists of a wedged between the tappet (32) and the sleeve ^ r ¹⁷ ■ 00 98 27/0255 & Aö - • 17- (33) exists. 4. Fuel pump according to claims 1 to 3, characterized in that the spring (38) consists of two helical, parallel compression springs consists, the ends of which are located on the sleeve are connected to one another. 5. Fuel pump according to claims 1 and 2, characterized in that the loading member consists of a die Sleeve (23) comprising connecting rod (78), which by means of a vacuum pump, the sleeve from the plunger (32) pulls away. BATH 009827/0255