Gear wheel

Abstract

A gear wheel (10), operable for transmitting substantial torques without developing or generating undue noise and exhibiting improved vibration damping, is axially mountable for operative rotation on a shaft (25) and includes a disc-shaped or cylindrical base body (11) that defines a recess (12) for passage of the shaft. The base body (11) carries a plurality of teeth (13, 14) radially distributed about the circumference of the base body. A disc-shaped damping element (17) is releasably connected to and against a side or face of the base body so as to accommodate relative movement between the base body and the damping element in response to dynamic loads acting on the operating gear wheel. A second damping element (17) can likewise be releasably connected to and against a second or opposite side or face of the base body so as to correspondingly accommodate relative movement between the base body and the second damping element in response to dynamic loads acting on the operating gear wheel.

Claims

1. A gear wheel axially mountable for operative rotation on a shaft, comprising: a base body defining a recess sized for passage of the shaft and having a plurality of teeth distributed radially along a circumference of the base body, wherein a first side of the base body is a planar radial first wall extending from the recess to the circumference of the base body, and wherein a second side of the base body is a planar radial second wall extending from the recess to the circumference of the base body; and a first disc-shaped damping element releasably entirely connected directly to and against the first side of the base body so as to accommodate relative movement between the base body and the damping element in response to dynamic loads acting on the operating gear wheel, wherein the first damping element has a radially outermost diameter that is smaller than a radially outermost diameter of the base body; wherein the first damping element has a recess that defines a radially inner most diameter that is substantially equal to the base body recess; and wherein the base body and the first damping element are produced from similar materials having similar hardness.

2. The gear wheel in accordance with claim 1, wherein the releasable connection between the first damping element and the base body is configured to accommodate said relative movement in the sub-micrometer to micrometer range.

3. The gear wheel in accordance with claim 2, wherein said relative movement is in the range of approximately 0.01 micrometers and 10 micrometers.

4. The gear wheel in accordance with claim 2, wherein said relative movement is directed in at least one of radially and circumferentially.

5. The gear wheel in accordance with claim 1, wherein said releasable connection of the first damping element and the base body comprises screws.

6. The gear wheel in accordance with claim 1, wherein said releasable connection of the first damping element and the base body comprises first screws disposed radially inside proximate the base body recess at a first radial distance from the base body recess and second screws disposed radially outside proximate the base body teeth at a second radial distance from the base body recess, wherein the second radial is greater than the first radial distance.

7. The gear wheel in accordance with claim 1, wherein the first damping element has a thickness that is smaller than a thickness of the base body.

8. The gear wheel in accordance with claim 1, further comprising a second disc-shaped damping element releasably connected to and against the second side of the base body so as to accommodate relative movement between the base body and the second damping element in response to dynamic loads acting on the operating gear wheel.

9. The gear wheel in accordance with claim 8, wherein each of the damping elements is directly releasably connected to the base body so that said relative movement between the each damping element and the base body generates friction between abutting end faces of the each damping element and the base body.

10. The gear wheel in accordance with claim 1, wherein the gear wheel forms a part of a gear box.

11. The gear wheel in accordance with claim 1, wherein the first damping element extends radially from the recess to an area proximate to the plurality of teeth distributed radially along the circumference of the base body, wherein the first damping element is configured to avoid interfering with engagement of the teeth of the first damping element with corresponding teeth of an adjoining element.

12. The gear wheel in accordance with claim 1, wherein the first damping element has opposing radially extending planar sides.

13. A gear wheel axially mountable for operative rotation on a shaft, comprising: a base body defining a recess sized for passage of the shaft and having a plurality of teeth distributed radially along a circumference of the base body, wherein a first side of the base body is a planar radial first wall extending from the recess to the circumference of the base body; and a first disc-shaped damping element releasably entirely connected directly to and against the first side of the base body so as to accommodate relative movement between the base body and the damping element in response to dynamic loads acting on the operating gear wheel a second disc-shaped damping element releasably connected to and against a second side of the base body so as to accommodate relative movement between the base body and the second damping element in response to dynamic loads acting on the operating gear wheel, wherein the second side of the base body is a planar radial second wall extending from the recess to the circumference of the base body, wherein an inner diameter of the second disc-shaped damping element is larger than the inner diameter of the first damping element; wherein the first damping element has a recess that defines a radially inner most diameter that is substantially equal to the base body recess; and wherein the base body and the first damping element are produced from similar materials having similar hardness.

14. The gear wheel in accordance with claim 13, wherein the second damping element is directly releasably connected to the base body so that said relative movement generates friction between abutting end faces of the first damping element and the base body.

Description

BRIEF DESCRIPTION OF THE DRAWINGS

(1) In the drawing, wherein similar reference characters denote similar elements throughout the several embodiments and views:

(2) FIG. 1 is an elevated perspective view of a gear wheel constructed in accordance with the present invention; and

(3) FIG. 2 is a cross-sectional partial view through the gear wheel of FIG. 1.

DETAILED DESCRIPTION OF THE PRESENTLY PREFERRED EMBODIMENTS

(4) The present invention relates to a gear wheel for transmitting torques, in particular such as a gear wheel of a gearbox that is operable for transmitting high torques, as for example a gearbox for a vertical rolling mill or an extruding drive.

(5) The gear wheel 10 depicted in FIGS. 1 and 2 has a disc-shaped or cylindrical base body 11 disposed radially within gear wheel 10 which defines a recess 12 for the passage of an axial shaft 25. The base body 11 of gear wheel 10 may, as is known, be shrunk or contracted onto (or otherwise mounted on or about) the shaft 25.

(6) Radially distributed along the outer circumference of the base body 11 of gear wheel 10 are a plurality of teeth. In the embodiment depicted in the drawings, closely similar or identical first teeth 13 and second teeth 14 provide helically-toothed rims 15 and 16, respectively.

(7) As will be apparent to those skilled in art, however, the inventive gear wheel need not be constructed as such a double helically-geared wheel, and embodiments having or incorporating by way of example a single helically-geared wheel and/or with straight-gear wheels should be understood as being within the intended scope and contemplation of the invention.

(8) A disc-shaped damping element 17 is releasably connected to the base body 11 of gear wheel 10 on or against at least one side or face of the body 11. In the illustrated embodiment of a double helically-geared wheel 10 in FIGS. 1 and 2, a separate disc-shaped damping element 17 is releasably connected to the base body 11 on each of the two opposite sides or faces thereof, so as to accommodate relative movements between the base body 11 and each of the damping elements 17 in response to operating forces and operating torques or stiffness fluctuations in the toothed engagement of wheel 10.

(9) As currently preferred, in the depicted embodiment this relative movement between base body 11 and each of the damping elements 17 lies in the sub-micrometer to micrometer range, in particular between about 0.01 m and 10 m.

(10) Each of the damping elements 17 shown in FIGS. 1 and 2 is releasably connected to base body 11 by screws 18, 19 on the respective side of body 11. In the depicted embodiment, first radially-inner screws 18 releasably connect each damping element 17 to base body 11 adjacent to or proximate the shaft-accommodating recess 12 of body 11, and second radially-outer screws 19 releasably connect each damping element 17 to base body 11 adjacent to or proximate the teeth 13, 14 of body 11. As seen in FIG. 1, each of the first and second screws 18, 19 are, in this particular embodiment, substantially evenly distributed circumferentially about damping elements 17 and form or define rings 20, 21 of the screws 18, 19.

(11) The attachment of the damping elements 17 to base body 11 via the screws 18, 19 allows and accommodates the desired relative movement during operation between the damping elements and the base body 11 of gear wheel 10. In addition, screws 18, 19 releasably connect each damping element 17 directly to base body 11 so that, during relative movement therebetween caused by operational loads or vibrations of the gear wheel 10, friction that develops or is generated between the respective damping element 17 and base body 11 effectively counteracts vibrations, thus reducing the development of noise.

(12) The adjoining or abutting end faces 22, 23 of base body 11 with each respective damping element 17 thus rub against one another during operation of the gear wheel as a result of the relative movement between the base body 11 and damping elements 17.

(13) Each damping element 17 of gear wheel 10, like the base body 11 of the gear wheel, includes a defined recess 24 for accommodating passage of the shaft 25. In the embodiment of the invention shown in the drawings, the inner diameter of the recess 24 of at least one of the disc-shaped damping elements 17 substantially corresponds to the inner diameter of the recess 12 of base body 11 of the gear wheel 10 and the outer diameter of shaft 25.

(14) More particularly, in the embodiment shown in FIGS. 1 and 2 gear wheel 11 abuts a shoulder of shaft 25 at the left face end of base body 11. Accordingly, the disc-shaped damping element 17 that is positioned on that left side of base body 11 defines a shaft passage recess 24 having a slightly larger inner diameter that is adapted to accommodate the shoulder of shaft 25.

(15) Each disc-shaped damping element 17 has an axial thickness that is smaller than the axial thickness of base body 11.

(16) The outer diameter of the each disc-shaped damping element 17 is smaller than the outer diameter of base body 11, so that the teeth 13, 14 are accessible without interfering with their meshed engagement with the teeth of an adjoining gear wheel or other element.

(17) In preferred embodiments, the base body 11 of gear wheel 10 and the damping elements 11 are produced from similar materials of similar hardness and, by way of preferred example, are produced from steel.

(18) Thus, the present invention provides a gear wheel of a gearbox 10, comprising a base body 11 carrying teeth 13, 14, and a disc-shaped damping element 17 releasably connected, on at least one side or face of the body 11, such that operating loads acting on gear wheel 10 cause relative movement between the damping element 17 and the base body 11. This relative movement preferably runs in the circumferential and/or radial direction and lies in the sub-micrometer to micrometer range. In the preferred embodiments herein described, the (or each) damping element 17 is directly connected to base body 11 of gear wheel 10 so that friction is generated between the adjacent or abutting end faces 22, 23 of the damping element 17 and base body 11. As a result of this construction and operating functionality, undesirable vibrations and the development of noise during operation and use of the gear wheel 10 is effectively counteracted and substantially eliminated or reduced.

(19) The invention is not limited by the embodiments described above which are presented as examples only but can be modified in various ways within the scope of protection defined by the appended patent claims.