Hand-held power tool transmission closure and hand-held power tool

Abstract

A hand-held power tool transmission closure having a base body for closing a transmission housing opening of a transmission housing of a hand-held power tool, in particular a hammer drill or a combi-hammer, wherein the hand-held power tool transmission closure includes a tube protruding from the base body, which extends in the transmission housing when the base body closes the transmission housing opening. The hand-held power tool transmission closure includes an air channel which extends in a first air channel section through the base body and in a second air channel section through the tube so that an air mass can flow through the air channel into and out of the transmission housing.

Claims

1. A hand-held power tool comprising: a transmission housing having a transmission housing opening; a transmission closure comprising: a base body closing the transmission housing opening; a tube protruding from the base body and extending into the transmission housing; and an air channel extending through the base body in a first air channel section and extending through the tube in a second air channel section, so that an air mass is able to flow through the air channel into and out of the transmission housing; an oscillation plate covering the transmission closure; and a spring situated below the oscillation plate and connected to the base body.

2. The hand-held power tool as recited in claim 1 wherein the tube has an inner diameter between 0.2 mm and 0.8 mm.

3. The hand-held power tool as recited in claim 2 wherein the tube has an inner diameter of 0.5 mm.

4. The hand-held power tool as recited in claim 1 wherein the tube protrudes from the base body in such a way that the tube ends at a hammer mechanism situated within the transmission housing.

5. The hand-held power tool as recited in claim 4 wherein the tube ends at a connecting rod of the hammer mechanism.

6. The hand-held power tool as recited in claim 1 further comprising a pressure valve situated in the first air channel section, an overpressure occurring in the transmission housing being decreasable via the pressure valve.

7. The hand-held power tool as recited in claim 6 wherein an underpressure occurring in the transmission housing is compensatable via the pressure valve.

8. The hand-held power tool as recited in claim 6 wherein the pressure valve is designed as a plate-shaped diaphragm having a central opening situated on a journal of the base body.

9. The hand-held power tool as recited in claim 8 wherein the base body includes an annular pressure distribution chamber closed by the plate-shaped diaphragm when the transmission internal pressure and the ambient pressure are the same.

10. The hand-held power tool as recited in claim 1 wherein the base body includes a sealing ring situated to seal the base body circumferentially with respect to the transmission housing opening.

11. The hand-held power tool as recited in claim 1 wherein the base body is designed as a plug.

12. The hand-held power tool as recited in claim 1 further comprising: a power tool housing enclosing the transmission housing.

13. A hammer drill or a combi hammer comprising the hand-held power tool as recited in claim 12.

14. The hand-held power tool as recited as recited in claim 1 wherein the spring is a leaf spring.

15. The hand-held power tool as recited as recited in claim 14 wherein the leaf spring is concave with respect to the oscillation plate and convex with respect to the base body.

16. The hand-held power tool as recited as recited in claim 1 wherein a longitudinal axis of the tube is angled with respect to a planar top surface of the base body.

17. The hand-held power tool as recited in claim 1 wherein the transmission housing houses a hammer mechanism.

18. The hand-held power tool as recited in claim 1 wherein the base body is located in the opening.

19. The hand-held power tool as recited in claim 1 wherein the tube extends through base body.

20. A hand-held power tool comprising: a transmission housing having a transmission housing opening; a transmission closure comprising: a base body closing the transmission housing opening; a tube protruding from the base body and extending into the transmission housing; and an air channel extending through the base body in a first air channel section and extending through the tube in a second air channel section, so that an air mass is able to flow through the air channel into and out of the transmission housing; a pressure valve situated in the first air channel section, an overpressure occurring in the transmission housing being decreasable via the pressure valve; wherein the pressure valve is designed as a plate-shaped diaphragm having a central opening situated on a journal of the base body.

21. The hand-held power tool as recited in claim 20 wherein the base body includes an annular pressure distribution chamber closed by the plate-shaped diaphragm when the transmission internal pressure and the ambient pressure are the same.

Description

BRIEF DESCRIPTION OF THE DRAWINGS

(1) In the figures, identical and equivalent components are provided with identical reference numerals.

(2) FIG. 1 shows a schematic and perspective representation of a sectional view of a hand-held power tool transmission closure according to the present invention;

(3) FIG. 2 shows a schematic representation of the hand-held power tool transmission closure from FIG. 1, which closes a transmission housing opening;

(4) FIG. 3 shows a schematic representation of the hand-held power tool transmission closure from FIG. 2, viewed from the rear and with a plotted intersection line A-A;

(5) FIG. 4 shows a schematic sectional representation of the hand-held power tool transmission closure according to intersection line A-A from FIG. 3, when the transmission internal pressure and the ambient pressure are essentially the same;

(6) FIG. 5 shows a schematic sectional representation of the hand-held power tool transmission closure according to intersection line A-A from FIG. 3, when the transmission internal pressure exceeds the ambient pressure;

(7) FIG. 6 shows a schematic sectional representation of the hand-held power tool transmission closure according to intersection line A-A from FIG. 3, when the transmission internal pressure drops below the ambient pressure;

(8) FIG. 7 shows a schematic illustration of a hand-held power tool, including a hand-held power tool transmission closure according to the present invention.

DETAILED DESCRIPTION

(9) A hand-held power tool transmission closure 10 in FIG. 1 includes a base body 1, which is provided to close a transmission housing opening, which is not illustrated. Hand-held power tool transmission closure 10 includes a tube 2 protruding from base body 1, which in the present case is provided as a metal tube. Hand-held power tool transmission closure 10 includes an air channel, which is formed by a first air channel section L1, which extends through base body 1, and by a second air channel section L2, which extends through tube 2. Due to this air channel formed by air channel sections L1, L2, an air mass LM is able to flow into and out of the transmission housing (See FIG. 2).

(10) In the present case, tube 2 has an inner diameter D of 0.5 mm. Since tube 2 protrudes from the underside of base body 1, tube 2 extends within the transmission housing when base body 1 closes a transmission housing opening. A sealing ring 6, which in the present case is made from an elastically deformable rubber, is situated circumferentially on base body 1.

(11) As illustrated in FIG. 1, hand-held power tool transmission closure 10 includes a pressure valve 3 situated in first air channel section L1, which in the present case is designed as a plate-shaped diaphragm having a central opening 3. Pressure valve 3 designed as a plate-shaped diaphragm is situated on a central journal 4 of base body 1. Base body 1 furthermore includes an annular pressure distribution chamber 5, which is closed by pressure valve 3 designed as a plate-shaped diaphragm.

(12) Due to pressure valve 3, an air mass LM may escape from the transmission housing, which is illustrated by the dashed line with arrow pointing away from base body 1. Moreover, an air mass LM is able to enter the transmission housing, from the transmission surroundings via pressure valve 3, which is indicated by the dashed line with arrow pointing in the direction of tube 2. The pressure regulating function of pressure valve 3 is explained in greater detail farther below with reference to FIGS. 4 through 6.

(13) FIG. 2 shows a hand-held power tool transmission closure 10, which closes a transmission housing opening 70 of a transmission housing 80. Base body 1 of hand-held power tool transmission closure 10 is held in transmission housing opening 70 by a circumferentially running sealing ring 6 and held in its position by a leaf spring 40 situated below an oscillation plate 50.

(14) As is also apparent from FIG. 2, tube 2 protrudes from base body 1 in such a way that tube 2 ends in the vicinity of a connecting rod 30 of hammer mechanism 60. More specifically, tube 2 protrudes from base body 1 in such a way that it extends up to movement axis A of connecting rod 30 without engaging with the range of motion of connecting rod 30, i.e., in particular without coming into contact with connecting rod 30regardless of a particular connecting rod length. Due to the installation situation shown in FIG. 2, an air exchange of transmission housing 80 is achieved without a lubricant being able to escape therefrom.

(15) FIG. 3 shows hand-held power tool transmission closure 10, including base body 1 and tube 2 protruding from the underside, a rear view of hand-held power tool transmission closure 10 being illustrated in FIG. 3 (viewed from the right with respect to FIG. 2). An intersection line A-A is plotted in FIG. 3, whose section A-A is explained in greater detail below with reference to FIG. 4.

(16) Section A-A illustrated in FIG. 4 shows hand-held power tool transmission closure 10 in its state when transmission internal pressure DI within transmission housing 80 and ambient pressure DU outside transmission housing 80 are essentially the same. Pressure valve 3 designed as a plate-shaped diaphragm rests on journal 4 of base body 1 in the undeflected state. No air exchange takes place via first and second air channel sections L1, L2 and via pressure valve 3. This is the case, for example, when the hand-held power tool has not been in operation for a long period of time or if a pressure compensation has already occurred during the operation of the hand-held power tool.

(17) FIG. 5 shows the state of hand-held power tool transmission closure 10 when transmission internal pressure DI exceeds ambient pressure DU, i.e., when an overpressure prevails in the transmission housing. This is the case, for example, when the hammer mechanism has heated a lubricant present in the transmission housing. An air mass LM flows into tube 2 protruding from base body 1 according to the dashed line with arrow and moves along air channel section L2 defined by tube 2 in the direction of base body 1. From there, air mass LM enters pressure distribution chamber 5 according to the dashed line with arrow, pressure distribution chamber 5 being situated in first air channel section L1 of base body 1. Due to an elastic deflection of pressure valve 3 provided as a plate-shaped diaphragm, air mass LM may escape from base body 1 on its upper side. As is also apparent from FIG. 5, pressure valve 3 designed as a plate-shaped diaphragm is lifted off of a first valve seat 1 situated on the outer circumference of base body 1. After a pressure compensation has taken place, pressure valve 3 returns to its initial position shown in FIG. 4.

(18) FIG. 6 now shows the state of hand-held power tool transmission closure 10 when transmission internal pressure DI drops below ambient pressure DU, i.e., when an underpressure prevails in transmission housing 80. This is the case, for example, when the hammer mechanism cools after a power tool operation. An air mass LM indicated by the dashed line with arrow may flow into annular pressure distribution chamber 5 on the upper side of base body 1 via pressure valve 3 designed as a plate-shaped diaphragm. Pressure valve 3 designed as a plate-shaped diaphragm lifts off of a second valve seat 1, which is situated on central journal 4 of base body 1. As indicated by the dashed line with arrow during the further progression, air mass LM flows further through base body 1 along first air channel section L1 until it reaches tube 2 protruding into air channel section L2 of base body 1 for the purpose of exiting tube 2 at its end, as illustrated by the dashed line with arrow. After a pressure compensation has taken place, pressure valve 3 returns to its initial position shown in FIG. 4.

(19) A hand-held power tool 100 is illustrated in FIG. 7. This hand-held power tool includes a power tool housing 90, which surrounds a transmission housing 80. A hammer mechanism 60, including a connecting rod 30, is situated within transmission housing 80. Hand-held power tool transmission closure 10 is situated in a transmission housing opening 70 and is covered on the upper side by an oscillation plate 50 of hand-held power tool 100. Tube 2 protruding from base body 1 of hand-held power tool transmission closure 10 ends in the vicinity of connecting rod 30 of hammer mechanism 60. Due to tube 2 protruding from base body 1, an undesirable exit of the lubricant from transmission housing 80 is avoided.

LIST OF REFERENCE NUMERALS

(20) D inner diameter of the tube DI transmission internal pressure DU ambient pressure L1 first air channel section L2 second air channel section LM air mass 1 base body 1 first valve seat 1 second valve seat 2 tube 3 pressure valve 3 central opening 4 central journal 5 pressure distribution chamber 6 sealing ring 10 hand-held power tool transmission closure 30 connecting rod 40 leaf spring 50 oscillation plate 60 hammer mechanism 70 transmission housing opening 80 transmission housing 90 power tool housing 100 hand-held power tool