DE102014220386B3 - Mechanical roller plunger - Google Patents

Abstract

Proposed is a mechanical roller tappet (1) for an OHV valve train of an internal combustion engine, with a hollow cylindrical housing (2) which can be arranged in an engine-side guide via its outer casing (3) and in the region of one end (4) a pocket (5 ), which receives on a bolt (6) extending cam follower roller (7), wherein in a further end (8) of the housing (2) outgoing bore (9) a push rod system (10) is applied, wherein the housing ( 2) is a pipe section or deep-drawn part, wherein the push rod system (10) as a hollow cylindrical, over its outer casing (11) in the bore (9) of the housing (2) extending sleeve, which in the section of the further end (8) of the housing ( 2) has its curved bottom (12) for direct contact of the push rod and wherein another end annular end (13) of the sleeve (10) on a bottom (14) of the housing (2), which consists of two Is formed on each other to curved tabs (15), which are separated from one of the cam follower roller (7) facing portion of the housing (2) and form the end (4).

Description

The invention relates to a mechanical roller tappet, in particular for an OHV valve train or an injection pump drive an internal combustion engine, with a hollow cylindrical housing which is arranged oscillating about its outer shell in an internal combustion engine leadership and in the region of a forehead has a pocket, the one on a bolt extending cam follower roller, wherein in a projecting from another end of the housing bore a push rod system is applied.

Such a roller tappet is in the textbook Grohe: "gasoline and diesel engines", Vogel-Buchverlag, 11th Edition 1995, ISBN 3-8023-1559-6, p 125-127 described. The roller tappet, as shown in Figure 8.1.5 on p. 127, is solid and has a thick wall in the region of its forehead with an intrusive pushrod system. A mechanical adjustment of a valve clearance takes place on the rocker arm actuated by the pushrod via an adjustment screw in a manner known per se.

The DE 197 48 164 A1 shows a plunger with a deep-drawn housing with a rotation and with retracted tabs for receiving the roller axis.

From the DE 41 31 487 A1 shows a valve clearance adjustment with a selectable in length sleeve 23 (see Sp. 1, Z. 56-68).

The US 2 145 485 A discloses a valve clearance adjustment by means of a screwed into a housing sleeve which is formed with a curved inwardly or outwardly bottom surface for the application of a push rod.

It is also in 3 of the JP 2012-189 055 A a plunger is shown, which consists of two nested, but oppositely oriented sleeves.

It is an object of the invention to provide a simple structure, easy to produce in mass production and weight optimized mechanical roller tappet.

According to the invention this object is achieved in that the housing is a piece of pipe or deep drawn, the push rod system is present as a hollow cylindrical, extending over its outer shell in the bore of the housing sleeve, which in the section of the other end of the housing their curved bottom for direct contact of Push rod has, with its other end annular end is on a bottom of the housing, which is formed of two mutually bent tabs, which are separated from a cam follower facing portion of the housing and form the front.

Thus, there is a roller tappet without the disadvantages mentioned above. The extruded or cast manufacturing used in the St. Technique is dispensed with. The thin-walled representation of the housing of the roller tappet made of deep-drawn sheet steel or of a thin-walled piece of pipe (for example, separation from a pipe string) reduces the manufacturing costs and reduces the mass of the roller tappet, which mass enters into the oscillating valve train masses. Thus, friction work is reduced.

In addition to a preferred application of the roller tappet in a valve or injection pump drive and other applications are conceivable and provided. So this can also be used in a general pump or compressor drive. This opens up to the expert a wide range, up to the conveyor or furniture technology.

According to a particularly preferred variant of the invention, the valve clearance is to be adjusted in the service or Erstmontagefall on the sleeve / the push rod system. This is, for example, thought of sleeves of different lengths, which are paired according to a measurement of the actual game accordingly. Also spacers are provided on the bottom of the housing. Alternatively, the sleeve and the bore of the housing may be provided with a thread, and the valve clearance is adjusted via a (countered) screw-in depth of the sleeve. Corresponding measure account for the rocker arm. For low-cost applications, the setting of the valve clearance may possibly be completely dispensed with.

An essential part of the invention is that the bottom of the housing is not solid and closed, but is formed of two mutually bent tabs, which are simply cut / punched from the lower portion of the housing and then bent towards each other.

In order to achieve more stability in the aforementioned range, it is proposed in concretization of the invention, for example, the ends of the lobes to be welded together.

Although the bag for the cam roller can be closed at one end. However, it is more expedient to present them by means of two flaps which are offset by 90 ° from the bottom flaps and are offset inwards. Their preferred planar design is achieved by embossing or bending.

In order to simplify the roller tappet with a number of other roller tappet on the internal combustion engine secured against rotation, it should be receivable in a holding bridge. For this purpose, it is proposed to apply to the further (upper) end corresponding crown-like material release, which serve to engage respective counterparts of the holding bridge.

For a non-rotating recording of the roller tappet in the engine-side leadership this may be proposed provided with a slot in the housing, which serves to engage a stationary counter body of the internal combustion engine. Alternatively, a Vedrehsicherungskörper such as a needle, a ball, etc. protrude from the housing.

The invention is apparent from the drawing.

1 shows a spatial view of the roller tappet;

2 shows a spatial view of the housing of the roller tappet and

3 shows a longitudinal section through the roller tappet.

Shown in the 1 . 3 a roller plunger 1 for a push rod valve drive of an internal combustion engine. This has a hollow cylindrical, deep-drawn sheet steel housing 2 (Sat. 2 ). The latter is about its largely smooth-walled outer jacket 3 can be arranged in an internal combustion engine side guide.

The housing 2 has a forehead in the area of his 4 a pocket 5 which consists of two of the forehead 4 depending tabs 16 is formed and between it a bolt 6 with a cam roller 7 take up. As you can see, the bolt is 6 end in holes 17 the tabs 16 attached. Every tab 16 is executed plan and over a Einkröpfung 18 above its bore 17 shifted in the direction of the axial line.

In one of another forehead 8th of the housing 2 outgoing bore 9 is a pushrod system 10 applied. The latter is present as a hollow cylindrical, thin-walled sleeve, which over its outer jacket 11 in the hole 9 of the housing 2 runs. She has in the section of the other, open forehead 8th of the housing 2 a bulged, one-piece tailed soil 12 , which serves to contact a push rod, which acts on the other end on a rocker arm. Optionally, the sleeve 10 also directly actuate a rocker arm.

It should be emphasized that the sleeve 10 with her other end of the ring 13 on a floor 14 of the housing 2 stands, which consists of two of the one forehead 4 of the housing 2 separate and mutually bent lobes 15 is formed. The rags 15 run 90 ° offset to the tabs 16 , About a height of the pressed sleeve 10 the valve clearance is adjusted mechanically, which need not be explained in detail at this point. On hydraulic adjustment measures is thus omitted.

It can be seen in the 1 . 2 moreover, that from the wider forehead 8th of the housing 2 two diametrically opposed material releases 19 out. These serve to hold the roller tappet 1 before its final assembly to the internal combustion engine in a transport bridge.

To protect against twisting in its combustion engine side guide, the roller tappet 1 on the outer jacket 3 his case 2 a slot 20 on. This is provided for engagement of an outgoing from the leadership, complementary Verdrehsicherungsansatzes.

LIST OF REFERENCE NUMBERS

1

roller plunger

2

casing

3

outer sheath

4

a forehead

5

bag

6

bolt

7

Cam nose role

8th

another forehead

9

drilling

10

Push rod system, sleeve

11

outer sheath

12

ground

13

annular end

14

ground

15

cloth

16

flap

17

drilling

18

Einkröpfung

19

Material exemption

20

Long hole

21

forehead

Claims (10)

Mechanical roller tappet ( 1 ), in particular for an OHV valve drive or an injection pump drive of an internal combustion engine, with a hollow cylindrical housing ( 2 ), which has its outer shell ( 3 ) can be arranged in an oscillating manner in an internal combustion engine leadership and in the field whose one forehead ( 4 ) a pocket ( 5 ), one on a bolt ( 6 ) running cam roller ( 7 ), wherein in one of another forehead ( 8th ) of the housing ( 2 ) outgoing bore ( 9 ) a push rod system ( 10 ) is applied, characterized in that the housing ( 2 ) is a pipe section or deep-drawn part, wherein the push rod system ( 10 ) as a hollow cylindrical, over its outer shell ( 11 ) in the hole ( 9 ) of the housing ( 2 ) extending sleeve, which in the section of the further forehead ( 8th ) of the housing ( 2 ) its arched floor ( 12 ) for direct contact of the push rod, with its other end annular end ( 13 ) on a floor ( 14 ) of the housing ( 2 ), which consists of two lobes ( 15 ) formed from one of the cam chuck ( 7 ) facing portion of the housing ( 2 ) are separated and the forehead ( 4 ) form. Roller tappet according to claim 1, characterized in that by means of the sleeve ( 10 ) the valve clearance is mechanically adjusted. Roller tappet according to claim 2, characterized in that the sleeve ( 10 ) into the hole ( 9 ) of the housing ( 2 ) is plugged or pressed and that for setting the valve clearance length-grouped held sleeves ( 10 ) are used. Roller tappet according to claim 2, characterized in that the sleeve ( 10 ) into the hole ( 9 ) of the housing ( 2 ) screwed and on the depth of engagement the valve clearance is set. Roller tappet according to claim 2, characterized in that the sleeve ( 10 ) into the hole ( 9 ) of the housing ( 2 ) is inserted or pressed and are provided for setting the valve clearance in thickness grouped held spacer rings, which directly on the ground ( 14 ) of the housing ( 2 ) and on which the sleeve ( 10 ) is at least indirectly. Roller tappet according to claim 1, characterized in that the bag ( 5 ) for the cam roller ( 7 ) from two offset by 90 ° to the lobes ( 15 ) from one forehead ( 4 ) depending tabs ( 16 ) is formed between which the bolt ( 6 ) with the cam roller ( 7 ) on which pin ( 6 ) end in holes ( 17 ) of the tabs ( 16 ) is attached. Roller tappet according to claim 6, characterized in that each tab ( 16 ) plan and over a Einkröpfung ( 18 ) above the bore ( 17 ) is shifted in the direction of the axial line. Roller tappet according to claim 1, characterized in that from the further end ( 8th ) of the housing ( 2 ) two diametrically opposed material releases ( 19 ) for a holder of the roller tappet ( 1 ) in a guide or transport bridge. Roller tappet according to claim 1, characterized in that the outer casing ( 3 ) of the housing ( 2 ) either with a slot ( 20 ) is provided for engagement of an outgoing from the engine side guide Verdrehsicherungsansatzes or that of the outer shell ( 3 ) of the housing ( 2 ) projecting radially a projection one or more parts for a rotationally secured engagement in a slot of the engine-side guide. Roller tappet according to claim 1, characterized in that the lobes ( 15 ) on one end ( 4 ) of the housing ( 2 ) on their adjacent foreheads ( 21 ) are welded / soldered together.

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