AU717358B2

AU717358B2 - Line boring machine

Info

Publication number: AU717358B2
Application number: AU40834/96A
Authority: AU
Inventors: Frank Seghezzi
Original assignee: Individual
Current assignee: Individual
Priority date: 1995-05-12
Filing date: 1996-01-05
Publication date: 2000-03-23
Anticipated expiration: 2016-01-05
Also published as: AU4083496A

Description

P/00/011 28/5/91 Regulation 3.2

AUSTRALIA

Patents Act 1990

ORIGINAL

COMPLETE SPECIFICATION STANDARD PATENT Name of Applicant: Actual Inventor Address for service is: Frank Seghezzi Frank Seghezzi WRAY ASSOCIATES 239 Adelaide Terrace Perth, WA 6000 i a a Attorney code: WR Invention Title: "Line Boring Machine" The following statement is a full description of this invention, including the best method of performing it known to me:- -2-

TITLE

Line Boring Machine FIELD OF THE INVENTION This invention relates to a line boring machine.

A line boring machine performs a machining operation on a work-piece by being mounted on the work-piece, rather than the work-piece is mounted on the boring machine as is the case with a conventional boring machine. This requires that the line boring machine be portable and of a compact construction.

BACKGROUND ART •o 10 Typical line boring machines have a spindle shaft on which a work tool can be mounted and a feed shaft for moving the work tool with respect to the worko:I piece. The spindle shaft and feed shaft are typically driven through gear trains which utilise planetary gears, spur gears and/or helical gears, all of which occupy significant space. Consequently, the existing machines can be rather bulky.

S• 15 It is against this background, and the problems and deficiencies associated therewith, that the present invention has been developed. The present invention in particular seeks to provide a line boring machine which is relatively compact in S° construction so as to be readily portable.

DISCLOSURE OF THE INVENTION The present invention provides a line boring machine comprising a spindle shaft, a drive shaft, a drive head drivingly connecting one end of the drive shaft to one end of the spindle shaft, a feed means for axially moving the spindle shaft, the feed means including a feed screw to which the drive head is operatively connected whereby rotation of the feed screw causes the drive head to move axially with respect to the feed screw to thereby cause axial movement of the -3spindle shaft, and first and second drive motors, the first drive motor being drivingly connected to the drive shaft through a first drive transmission means, and the second drive motor being drivingly connected to the feed screw through a second drive transmission means, the first and second drive transmission means each comprising a compound worm and worm gear train.

The compound worm and worm wheel gear train provides a high reduction ratio between each motor and the drive shaft and feed screw respectively, so providing a significant speed reduction and a significant torque increase.

The use of the compound worm and worm wheel gear trains allows the machine to be of compact construction.

Each compound worm and worm gear train preferably comprises a worm :o*.provided on an input shaft connected to the respective motor, a worm wheel mounted on an intermediate shaft and in meshing engagement with the worm, a further worm provided on the intermediate shaft, and a further worm wheel 15 mounted on an output shaft and in meshing engagement with the further worm.

In the first drive transmission means, the output shaft is drivingly connected to eq the drive shaft.

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o In the second drive transmission means, the output shaft is drivingly connected °oet° to the feed screw.

Coe C 9 The feed screw may be drivingly connected to the spindle through gearing. The gearing may include a drive gear which is splined or otherwise slidably supported on the drive shaft for movement therealong while rotating in unison therewith.

BRIEF DESCRIPTION OF THE DRAWINGS The invention will be better understood by reference to the following description of one specific embodiment thereof as shown in the accompanying drawings in which: -4- Figure 1 is a schematic view of a line boring machine according to the embodiment; Figure 2 is a partly sectioned side view of the line boring machine; Figure 3 is a partly sectioned plan view of the line boring machine; Figure 4 is an end view of the line boring machine; Figure 5 is a schematic view of a first compound worm and worm wheel gear train used in the line boring machine; Figure 6 is a schematic view of a second compound worm and worm wheel gear train used in the line boring machine; •9 0 Figure 7 is a schematic view showing the line boring machine mounted on a angle mounting attachment; and o0o0 Figure 8 is a schematic view of facing attachment for use as an accessory 0o.. with the line boring machine.

0* e• 0*° BEST MODE(S) FOR CARRYING OUT THE INVENTION 15 The embodiment shown in the drawings is directed to a line boring machine for carrying out machining operations on a work-piece (not shown). Typically, the line boring machine is mounted directly onto the work-piece in conventional fashion.

The line boring machine 10 includes a machine body 11 onto which two motors 13, 15 are mounted, as shown in Figure 1 of the drawings. In this embodiment, the two motors comprise a first electric motor 13 and a second electric motor The first electric motor 13 operates under the control of a first control unit 17 connected to the motor by cable 18. The second electric motor 15 operates under the control of a second control unit 19 connected to the motor by mains power cable 20. The two control units 17, 19 are connected electrically to a main power supply (not shown) by way of cable 21.

The machine body 11 includes a main housing 23 which in this embodiment is typically formed of a suitable metal such as cast iron or aluminium. The machine body 11 also includes a head stock 25 which provides a drive head 26. The head stock 25 supports a spindle housing 27 which extends between the head stock and the main housing 23. A spindle shaft 29 is rotatably supported within the spindle housing 27 in needle roller thrust bearings (not shown). One end of the spindle shaft 29 extends beyond the spindle housing 27 and carries a holder 31 which is adapted to receive and hold a work tool or accessory device.

The head stock 25 is slidably supported on a stablising shaft 32 which extends got: between the head stock and the main housing 23, with the stabilising shaft being fixed in cantilever fashion to the main housing 23. With this arrangement, the o; drive head 26 is slidably movable along the stabilising shaft 32. Graduations 33 are provided on the stabilising shaft 32 to provide a visual indication of the extent of movement of the drive head 26 with respect to the stabilising shaft 32.

A first drive means 41 is provided for rotating the spindle shaft 29, and a second drive means 42 is provided for moving the spindle shaft 29 axially.

too**: 0°° The first drive means 41 includes a drive shaft 43 drivingly connected to the end 0..

of the spindle shafts 29 remote from the holder 31 through a gear train mounted within the drive head 26. The gear train 45 includes a drive gear 47, which is in the form of a spur gear, mounted on the drive shaft 43 for axial movement therealong while rotating in unison with the drive shaft. This connection between the drive shaft 43 and the drive gear 47 comprises a spline connection which includes an external spline 49 on the drive shaft 43 and a complimentary internal spline 50 on the drive gear 47. With this arrangement, rotational torque applied to the drive shaft 43 is transmitted through the spline connection to the drive gear 47 while allowing the drive gear to move axially along the drive shaft in unison with movement of the drive head.

-6- The first motor 13 is drivingly connected to the drive shaft 43 through a first drive transmission means 52 which includes a first compound gear train 48, as best seen in Figure 5 of the drawings. The drive transmission means 52 includes an input shaft 51 one end of which is drivingly coupled to the first motor 13 through a coupling 53. A first worm 55 is provided on the input shaft 51. A worm wheel 57, which mounted on an intermediate shaft 59, is in meshing engagement with the worm 55 such that rotational torque applied to the input shaft 51 is transmitted to the intermediate shaft 59, with appropriate speed reduction and torque increase transmitted through the meshing worm 55 and worm wheel 57.

A second worm 61 is provided on the intermediate shaft 59. The second worm 61 is in meshing engagement with a worm wheel 63 mounted on an output shaft The output shaft 65 is connected to the drive shaft 43. Rotational torque applied to the intermediate shaft 59 is transmitted through the meshing worm 61 oooo and worm wheel 63 to the output shaft 65 and then to the drive shaft 43. The

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15 meshing worm 61 and worm wheel 63 provides a speed reduction and a torque o increase between intermediate shaft 59 and the output shaft With this arrangement, the high speed, low torque output of the first electric motor 13 is transmitted through the compound gear train 48 (comprising worm 55, worm wheel 57, worm 61 and worm wheel 63), to provide a low speed, high 20 torque output at the drive shaft 43. As previously mentioned, rotational torque 45 8666"from the drive shaft 43 is transmitted through the gear train 45 to the drive spindle 29.

The second drive means 42 comprises a screw mechanism 70 which includes feed screw 71 mounted on the main housing 23 and a nut 73 mounted on the drive head 26 in threaded engagement with the feed screw 71. Rotation of the feed screw 71 causes the nut 73 to move axially along the feed screw to thereby cause the drive head 26 to move towards or away from the main housing 23, according to the direction of rotation of the feed screw 71. This movement of the drive head 26 causes axial movement of the drive spindle 29 and so displacement of any work tool or other device (not shown) mounted thereon at the holder 31.

-7- The second motor 15 is drivingly connected to the feed screw 71 through a second drive transmission means 82 which includes a second compound gear train 83 which is best shown in Figure 6 of the drawings. The drive transmission means 82 includes input shaft 85 one end of which is drivingly coupled to the second motor 15 through a coupling 87. A second worm 89 is provided on the input shaft 85. A worm wheel 91 mounted on an intermediate shaft 93 is in meshing engagement with the worm gear 95 such that rotational torque applied to the input shaft 85 is transmitted to the intermediate shaft 93, with appropriate speed reduction and torque increase transmitted through the meshing worm 89 and worm wheel 91. A second worm 95 is provided on the intermediate shaft 93.

The second worm 95 is in meshing engagement with a worm wheel 97 on an output shaft 99. The output shaft 99 is provided with the feed screw 71.

Rotational torque applied to the intermediate shaft 93 is transmitted through the meshing worm 95 and worm wheel 97 to the output shaft 99 and then to the S 15 feedscrew 71. The meshing worm 95 and worm wheel 97 provides a speed reduction and a torque increase between intermediate shaft 85 and the output S*shaft 99.

With this arrangement, the high speed, low torque output of the second electric motor 15 is transmitted through the compound gear train 83 comprising worm 89, 20 worm wheel 91, worm 95 and worm wheel 97, to provide a low speed, high torque output at the feed screw 71.

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In operation, the rate at which the drive spindle rotates the tool and the rate at which the tool moves axially with respect to a work-piece on which it is performing a machining operation can be controlled by the operator by way of two control units 17, 19. Control unit 17 allows the operator to selectively regulate the speed of the first electric motor 13 which in turn controls the rate at which the spindle 29 rotates the tool. The control unit 19 allows the operator to selectively control the rate at which the tool is advanced or withdrawn with respect to the work-piece. In particular, the control unit 19 regulates the speed of the second electric motor 15 which drives the feed screw 71 and so controls the rate at which the drive head 26 is moved with respect to the main casing 23.

-8- The use of the compound worm gear assemblies 48, 83 is particularly advantageous in providing a machine which is of compact construction and thereby readily portable.

The machine 10 can be used in association with various accessory devices, one of which is shown in Figure 7 and another of which is shown in Figure 8.

Referring now to Figure 7, there is shown an angle plate 101 which can be used to mount the machine 10 onto a work-piece and to allow the machine 10 to be angularly adjusted with respect to the work-piece as necessary.

Figure 8 illustrates an angle facing attachment 103 having a boring bar 105 which can be connected to the holder 31 of the spindle shaft 29.

It should be appreciated that the scope of the invention is not limited to the scope o of the embodiment described. In particular, it should be understood that the motors 13, 15 need not be electric motors; they can, for example, be hydraulic motors or pneumatic motors operating under the control of a suitable control circuit.

a. i Throughout the specification, unless the context requires otherwise, the word "comprise" or variations such as "comprises" or "comprising", will be understood to imply the inclusion of a stated integer or group of integers but not the :...xclusion of any other integer or group of integers.

exclusion of any other integer or group of integers.

Claims

1. A line boring machine comprising a spindle shaft, a drive shaft, a drive head drivingly connecting one end of the drive shaft to one end of the spindle shaft, a feed means for axially moving the spindle shaft, the feed means including a feed screw to which the drive head is operatively connected whereby rotation of the feed screw causes the drive head to move axially with respect to the feed screw to thereby cause axial movement of the spindle shaft, and first and second drive motors, the first drive motor being drivingly connected to the drive shaft through a first drive transmission means, and the second drive motor being drivingly connected to the feed screw through a second drive transmission means, the first and second drive transmission means each comprising a compound worm and worm gear l train.

2. A line boring machine according to claim 1 wherein each compound worm and worm gear train comprises a worm provided on an input shaft connected to the respective motor, a worm wheel mounted on an intermediate shaft and in meshing engagement with the worm, a further worm provided on the intermediate shaft, and a further worm wheel mounted on an output shaft and "in meshing engagement with the further worm. °°oo° 20

3. A line boring machine according to claim 2 wherein the output shaft is drivingly connected to the drive shaft in the first drive transmission means.

4. A line boring machine according to claim 2 or 3 wherein the output shaft is drivingly connected to the feed screw in the second drive transmission means.

5. A line boring machine according to any one of the preceding claims wherein the feed screw is drivingly connected to the spindle through gearing.

6. A line boring machine according to claim 5 wherein the gearing includes a drive gear which is splined or otherwise slidably supported on the drive shaft for movement therealong while rotating in unison therewith.

7. A line boring machine in substantially as herein described with reference to the accompanying drawings. Dated this THIRTY-FIRST day of DECEMBER 1999 FRANK SEGHEZZI Applicant Wray Associates Perth, Western Australia Patent Attorneys for the Applicant 4