GB1592312A

GB1592312A - Gearboxes

Info

Publication number: GB1592312A
Application number: GB394077A
Authority: GB
Original assignee: DAVALL GEAR CO Ltd
Current assignee: DAVALL GEAR CO Ltd
Priority date: 1978-01-25
Filing date: 1978-01-25
Publication date: 1981-07-08

Description

(54) IMPROVEMENTS IN OR RELATING TO GEARBOXES (71) We, THE DAVALL GEAR COMPANY LIMITED, of 29 Linkfield Lane, Redhill, Surrey, RHi 1JH, a British Company, do hereby declare the invention, for which we pray that a patent may be granted to us, and the method by which it is to be performed, to be particularly described in and by the following statement: This invention relates to drive assemblies incorporating gearboxes, especially for use in locations where the space available is restricted.

The invention is capable of application in many practical forms but is particularly concerned with gearbox drive assemblies used for effecting translatory movement of an essentially flat component, for instance a panel member such as a door, a window or a roof member, in its own plane. It is to be understood, however, that use for this purpose is illustrative only and that the invention is not restricted to effecting translatory movement of flat components only, as other forms of movement and other kinds of component can be moved using mechanisms which incorporate drive assemblies embodying this invention.

According to this invention, there is provided a drive assembly comprising a gearbox having an input shaft and an output shaft coupled thereto by an intermediate spiroid gear train comprising a spiroid gear mounted on each shaft, the output member which is operatively connected with a cooperating member, such that rotation of the input shaft is transmitted to the output member which effects relative movement between the gearbox and the cooperating member.

Preferably, the input shaft is connected to a motor, for example, an electric motor, whereby the shaft can be rotated, possibly via a clutch or flexible coupling.

The intermediate gear train may comprise a spiroid worm mounted on the input shaft and a second spiroid gear mounted on the output shaft, the spiroid elements meshing together and the second spiroid gear constituting the output member. The rotational axes of the two spiroid elements may be arranged to provide a self-locking effect in which the output shaft can be driven in either direction by a torque applied to the input shaft and the input shaft cannot be driven in either direction by a torque applied to the output shaft.

This particular arrangement provides a wide choice of gear reduction ratios, for example, 4:1 to 100:1. Thus, in certain applications, this self-locking feature provides an antitheft arrangement, such as an application being discussed hereinbelow.

The intermediate spiroid gear train may have its output spiroid gear constituting both the gear mounted on the output shaft and the output member meshing with a rack.

The work "rack" is intended herein to include conventional toothed racks, synchronous belts, toothed, ball or roller chain, flexible toothed racks and the like.

A gearbox drive assembly in accordance with the invention, which has been developed in connection with the construction of a motor operated sunlight roof structure for a vehicle, either having a rigid slidable panel or a flexible panel associated with a slidable cross member, will now be described by way of example and with reference to the accompanying drawings in which: Figure 1 is a partial plan view of a gear box drive assembly, with a self-locking feature, for use in a vehicle sunlight roof structure; Figure 2 is a partial sectional view of the assembly shown in Figure 1; and Figures 3 to 8 show various forms of rack that can be used in gearbox drive assemblies in accordance with the invention.

Rigid panel vehicle sunlight roofs comprise a generally rectangular well in the vehicle roof in which a rigid panel is located, the panel being capable of sliding in the fore-and-aft direction of the vehicle between a first end position, in which the panel completely closes the opening in the roof inside the well, and a second end position, in which the panel is largely disposed under (or over) a fixed part of the vehicle roof and the roof opening is unobstructed as much as possible. Flexible sliding roofs also have a roof well and, in its first end position, the slidable cross member is located adjacent the forward transverse rim of the well so that the flexible roof panel, having its forward edge attached to the cross member, is stretched over and thus closes the roof opening. In its second end position, the cross member is adjacent the rearward transverse edge of the roof opening and the flexible roof panel is folded at a plurality of transverse lines and typically rests upon the fixed part of the vehicle roof. In either construction, the forward transverse part of the movable component, i.e. either the forward edge of the rigid roof panel or the slidable cross member per se, can house a motor, preferably an electric motor, actuation of which can be arranged to drive the movable component towards one or other of its end positions, so as to open or close the sliding roof construction.

The movable roof component can house a centrally-located electric motor having two output shafts each extending transversely of the vehicle to the respective side of the roof opening where it forms the input shaft to a gearbox construction embodying the invention. Each output shaft extends laterally from the movable roof component and the output member operatively engages a cooperating member, e.g. a gear rack associated with the respective side edge of the roof opening.

Referring now to Figures 1 and 2, an output shaft 20 (Figure 2) from a motor (not shown) drives a clutch or coupling 21 for an input shaft 23 which is journalled in a gearbox housing 24. The input shaft 23 is mounted in a bearing 25 (Figure 1) and its remote end extends into the gearbox housing 24 and is supported in a second bearing 30 supported in a bearing support 26 integral with a transverse web 27 forming part of the gearbox housing.

Between the bearings 25 and 30, the input shaft 23 carries an input spiroid worm 28 which is in mesh with an output spiroid gear 29 journalled upon a shaft 31 mounted between bearing supports forming part of the gearbox housing 24 and arranged so that the axis of the shaft 31 is displaced from, and at right angles to, the axis of the input 23. The gear 29 has an integral spur gear element 32 on its underside which meshes with a gear rack 38 forming the upright outer side, in effect, of the respective rack of the roof opening frame. The rack 38 is of generally inverted T section, as shown in Figure 2 and as indicated at 34, and the gear teeth of the rack 38 form the inside face of one part of the upright of the T, whereas the other side is formed as a guide channel 35 in which a guide wheel or roller 39, or a series of such wheels or rollers or a slider are located. As shown in Figure 2, the guide wheels or rollers 39 are mounted on dependent shafts 40 appropriately mounted on the outside of the gearbox housing 24 and these serve to ensure that the entire structure undergoes translatory movement forward and rearwardly relative to the gear rack 38, as the motor (not shown) incorporated in the leading edge of the roof panel is actuated.

This particular arrangement of input and output spiroid elements 28,29 provides a selflocking feature, whereby the shaft 31, and hence the spiroid gear 29, can be driven in either direction by a torque applied to the input shaft 23 from the motor via the clutch or coupling 21. However, the application of a torque to the spiroid gear 29, such as by attempting to move the structure relative to the gear rack 38, does not drive the input shaft 23 and, hence, an anti-theft arrangement is provided. Thus, if an attempt is made to slide open the rigid panel of a rigid sliding roof or the slidable cross member of a flexible sliding roof, this self-locking feature prevents such a movement with respect to the gear rack at either side of the roof opening, only the drive from the motor causing the opening or closing of the roof.

Figures 3 to 8 show various forms of gear rack that may be used with the assembly described above. The left hand side of each of Figures 3 to 8 is an elevation and the right hand side a section.

The gear rack shown in Figure 3 is in the form of a conventional rigid rack and that shown in Figure 4 is a synchronous belt.

Figure 5 shows a toothed chain for use as a gear rack and Figures 6a and 6b show a ball chain-and roller chain-type gear rack, respectively.

Figure 7 is a gear rack in the form of a flexible rack having slots between adjacent teeth to provide the necessary flexibility and Figure 8 is another form of flexible gear rack having discrete teeth secured to a fabric or other flexible tension member.

Operation of the electric motor to drive the rigid panel or cross member in either of its directions of movement is effected by supplying current to the motor from the vehicle battery, for instance under the control of a switch which may be located within the vehicle adjacent the driving position. The switch is preferably arranged to have three positions, one of which operates the motor to cause rearward movement of the panel or cross member, a second of which operates the motor in the reverse direction to cause forward, that is closing, movement of the panel or cross member, and a third neutral or off position in which no operation of the motor occurs. The switch can, if designed, be spring-biased to the third position so that operation of the sliding roof panel requires the user to move the switch into and hold it in the respective one of the other two positions. The arrangement can also be so provided that operation of the switch, to cause the motor to open the sliding roof by moving the rigid panel or cross member rearwardly, first initiates lowering of the rear edge of the panel or cross member so that it can then slide rearwardly under the fixed part of the vehicle roof.

The invention thus. provides a gearbox drive assembly which incapable or providing considerable advantages and, in particular, is eminently suited to the particular application discussed above, namely, for effecting translatory movement within its own plane of a flat panel, such as a vehicle sliding roof member, or the corresponding operation of the forward cross member of a flexible vehicle roof construction.

Also, the invention solves the problem of providing a gearbox drive assembly which can be housed within the restricted height provided between the upper and lower surfaces of a rigid sliding panel or flexible roof cross member.

However, it will be appreciated that the assembly described above can be applied to a much wider field of applications, some of the best choices are described below and further possibilities might contain the best features from the construction described above.

TYPES OF APPLICATION a) Vehicle windows and ventilators.

b) House and greenhouse windows, hinged or sashed.

c) Shutter blinds for shops and vehicles.

d) Drawers in desks and security cabinets.

e) Sun blinds.

f) Sluice gates, dampers, fire doore, garage doors.

g) Vehicle seat adjustment actuators.

h) Curtain actuators.

i) General opening and closing of apertures.

It will be appreciated also that the output member could comprise a capstan about which is wound a cable or rope, constituting the cooperating member, such that, on rotation of the input shaft, the capstan is rotated to effect relative movement between the gearbox and cable or rope.

WHAT WE CLAIM IS: 1. A drive assembly comprising a gearbox having an input shaft and an output shaft coupled thereto by an intermediate spiroid gear train comprising a spiroid gear mounted upon each shaft, the output shaft carrying an output member which is operatively connected with a cooperating member, such that rotation of the input shaft is transmitted to the output member which effects relative movement between the gearbox and the cooperating member.

2. An assembly as claimed in Claim 1, in which the input shaft is connected to a motor, whereby the shaft can be rotated.

3. An assembly as claimed in Claim 2, in which the input shaft can be rotated by the motor via a clutch or flexible coupling.

4. An assembly as claimed in any of Claims 1 to 3, in which the intermediate gear train comprises a spiroid worm mounted on the input shaft and a second spiroid gear mounted on the output shaft, said spiroid elements meshing together and the second spiroid gear constituting the output member.

5. An assembly as claimed in Claim 4, in which the rotational axes of the two spiroid elements are arranged to provide a self-locking effect in which the output shaft can be driven in either direction by a torque applied to the input shaft but the input shaft cannot be driven in either direction by a torque applied to the output shaft.

6. An assembly as claimed in any preceding claim, in which the output member comprises a toothed drive wheel meshing with an elongate gear rack in the form of a rigid-toothed gear rack a synchronous belt or a flexible-toothed gear rack, said elongate gear rack constituting the cooperating member.

7. An assembly as claimed in any preceding claim, in which the gear ratio is 4:1 to 100:1.

8. A drive assembly substantially as hereinbefore described with reference to the accompanying drawings.

9. A sliding rigid panel, vehicle sunlight roof comprising a substantially rigid, planar panel locatable in a correspondingly dimensioned well in a vehicle roof, the panel being capable of sliding in the fore-and-aft direction of the vehicle, in use, between a first end position, in which the panel closes the opening in the roof well, and a second end position, in which the panel is disposed substantially under or over a fixed part of the vehicle roof, and a drive assembly for the roof and as claimed in any preceding claim, which is connected between the panel and vehicle roof and which provides said sliding movement of the panel in the fore-and-aft directions of the vehicle.

10. A flexible, sliding vehicle sunlight roof comprising a slidable cross member located in the front end of a flexible roof panel located in a well in a vehicle roof, the cross-member being capable of sliding in the fore-and-aft direction of the vehicle, in use, between a first end position, in which the flexible panel closes the opening in the roof well, and a second end position, in which the flexible panel causes the roof well opening to be open, and a drive assembly for the roof and as claimed in any of Claims 1 to 8, which is connected between the cross member and vehicle roof and provides said sliding movement in the fore-and-aft directions of the vehicle.

11. A vehicle sunlight roof as claimed in Claim 9, or 10, in which the cooperating member is located on a side of the vehicle roof well and the remainder of the construction including the output member, is located at the front end of the rigid panel or on the cross member, as the case may be.

12. A vehicle sunlight roof as claimed in Claim 11, in which the front end of the rigid panel or the cross member comprises a transverse channel member in which the remainder of the gearbox is located.

13. A sliding rigid panel, vehicle sunlight roof or a flexible sliding vehicle roof substantially as hereinbefore described with reference to the accompanying drawings.

**WARNING** end of DESC field may overlap start of CLMS **.

Claims

**WARNING** start of CLMS field may overlap end of DESC **.

The invention thus. provides a gearbox drive assembly which incapable or providing considerable advantages and, in particular, is eminently suited to the particular application discussed above, namely, for effecting translatory movement within its own plane of a flat panel, such as a vehicle sliding roof member, or the corresponding operation of the forward cross member of a flexible vehicle roof construction.

Also, the invention solves the problem of providing a gearbox drive assembly which can be housed within the restricted height provided between the upper and lower surfaces of a rigid sliding panel or flexible roof cross member.

However, it will be appreciated that the assembly described above can be applied to a much wider field of applications, some of the best choices are described below and further possibilities might contain the best features from the construction described above.

TYPES OF APPLICATION a) Vehicle windows and ventilators.

b) House and greenhouse windows, hinged or sashed.

c) Shutter blinds for shops and vehicles.

d) Drawers in desks and security cabinets.

e) Sun blinds.

f) Sluice gates, dampers, fire doore, garage doors.

g) Vehicle seat adjustment actuators.

h) Curtain actuators.

i) General opening and closing of apertures.

It will be appreciated also that the output member could comprise a capstan about which is wound a cable or rope, constituting the cooperating member, such that, on rotation of the input shaft, the capstan is rotated to effect relative movement between the gearbox and cable or rope.

WHAT WE CLAIM IS: 1. A drive assembly comprising a gearbox having an input shaft and an output shaft coupled thereto by an intermediate spiroid gear train comprising a spiroid gear mounted upon each shaft, the output shaft carrying an output member which is operatively connected with a cooperating member, such that rotation of the input shaft is transmitted to the output member which effects relative movement between the gearbox and the cooperating member.
2. An assembly as claimed in Claim 1, in which the input shaft is connected to a motor, whereby the shaft can be rotated.
3. An assembly as claimed in Claim 2, in which the input shaft can be rotated by the motor via a clutch or flexible coupling.
4. An assembly as claimed in any of Claims 1 to 3, in which the intermediate gear train comprises a spiroid worm mounted on the input shaft and a second spiroid gear mounted on the output shaft, said spiroid elements meshing together and the second spiroid gear constituting the output member.
5. An assembly as claimed in Claim 4, in which the rotational axes of the two spiroid elements are arranged to provide a self-locking effect in which the output shaft can be driven in either direction by a torque applied to the input shaft but the input shaft cannot be driven in either direction by a torque applied to the output shaft.
6. An assembly as claimed in any preceding claim, in which the output member comprises a toothed drive wheel meshing with an elongate gear rack in the form of a rigid-toothed gear rack a synchronous belt or a flexible-toothed gear rack, said elongate gear rack constituting the cooperating member.
7. An assembly as claimed in any preceding claim, in which the gear ratio is 4:1 to 100:1.
8. A drive assembly substantially as hereinbefore described with reference to the accompanying drawings.
9. A sliding rigid panel, vehicle sunlight roof comprising a substantially rigid, planar panel locatable in a correspondingly dimensioned well in a vehicle roof, the panel being capable of sliding in the fore-and-aft direction of the vehicle, in use, between a first end position, in which the panel closes the opening in the roof well, and a second end position, in which the panel is disposed substantially under or over a fixed part of the vehicle roof, and a drive assembly for the roof and as claimed in any preceding claim, which is connected between the panel and vehicle roof and which provides said sliding movement of the panel in the fore-and-aft directions of the vehicle.
10. A flexible, sliding vehicle sunlight roof comprising a slidable cross member located in the front end of a flexible roof panel located in a well in a vehicle roof, the cross-member being capable of sliding in the fore-and-aft direction of the vehicle, in use, between a first end position, in which the flexible panel closes the opening in the roof well, and a second end position, in which the flexible panel causes the roof well opening to be open, and a drive assembly for the roof and as claimed in any of Claims 1 to 8, which is connected between the cross member and vehicle roof and provides said sliding movement in the fore-and-aft directions of the vehicle.
11. A vehicle sunlight roof as claimed in Claim 9, or 10, in which the cooperating member is located on a side of the vehicle roof well and the remainder of the construction including the output member, is located at the front end of the rigid panel or on the cross member, as the case may be.
12. A vehicle sunlight roof as claimed in Claim 11, in which the front end of the rigid panel or the cross member comprises a transverse channel member in which the remainder of the gearbox is located.
13. A sliding rigid panel, vehicle sunlight roof or a flexible sliding vehicle roof substantially as hereinbefore described with reference to the accompanying drawings.
14. A vehicle window, ventilator, hinged

window, sashed window, shutter blind, furniture drawer, sun blind, sluice gate, damper, fire door, garage door, vehicle seat, curtain or any other member which is associated with a structure for movement with respect thereto and which incorporates a drive assembly, as claimed in any of Claims 1 to 8, interconnecting the member and structure to provide said movement therebetween.