GB2232011A

GB2232011A - Terminal adapter in an electric motor

Info

Publication number: GB2232011A
Application number: GB8910809A
Authority: GB
Inventors: Georg Strobl
Original assignee: Johnson Electric SA
Current assignee: Johnson Electric SA
Priority date: 1989-05-11
Filing date: 1989-05-11
Publication date: 1990-11-28
Also published as: DE9005359U1; JPH0326261U; GB8910809D0; CN2079382U

Abstract

A fractional horsepower PMDC motor includes adapting means 20, 22, 24 for adapting the configuration of terminals 14 of the motor. The adapting means comprises a plastics support 20 and a conductor 22 which bridges a gap 52 in the support. A second terminal 24 is riveted to the conductor above the gap 52, where access can be held to the end of the second terminal 24 to form the rivet. By supporting the conductor 22 on either side of the second terminal 24, pressure on the second terminal 24 when installing the assembled motor will not cause deformation of the conductor 22 which might otherwise cause the second terminal 24 to short with the end cap 4. <IMAGE>

Description

TERMINAL ADAPTER IN AN ELECTRIC MOTOR The present invention relates to a terminal adapter in an electric motor.

Typically a fractional horsepower permanent magnet direct current motor is provided with two spade terminals which project axially from the motor end cap. When the end user requires a different termi nal configuration, it is necessary to redesign the motor end cap, which is not a simple option as the end cap generally supports a bearing for the motor shaft and may support the motor brush gear also. Accordingly it is desirable to provide a device which will clip on the end cap, over the motor terminals, to change the terminal configuration.

The present invention provides a fractional horsepower PMDC motor comprising an end cap and a first terminal, and adapting means for adapting the terminal configuration of the motor, said adapting means comprising an electrically insulating support arranged to be carried on said end cap, a conductor carried by said support and arranged to electrically contact said first terminal, and a second terminal joined to said conductor, wherein said conductor bridges a gap in the support and the second terminal is joined to said conductor in the region of said gap.

By connecting the second terminal to the conductor at a region which bridges a gap in the support it is possible to gain access to the underside of the conductor to facilitate connection of the conductor and second terminal whilst the conductor is mounted on the support. Also, as the support supports the conductor to either side of the second terminal it will ensure that it is held clear of the end cap in the event that pressure is applied to the second terminal, in the direction of the end cap, during installation of the motor.

Other, preferred, features and advantages of the invention will be apparent from the following description and the accompanying claims.

The invention will be further described by way of example with reference to the accompanying drawings in which: Figure 1 is an exploded view of a permanent magnet direct current motor forming an embodiment of the invention; Figure 2 is an enlarged cross-sectional view along the line II-II of Figure 1 of the assembled motor; and Figure 3 is an enlarged cross-sectional view along the line III-III of Figure 1 of the assembled motor.

Referring to the drawings, a fractional horsepower PMDC motor forming an embodiment of the invention comprises a deep drawn can-like steel casing 2 having a plate-like metal end cap 4 which closes its open end 6. A plastics holder 8 inside the casing 2 carries brushgear and suppression elements for the motor (not shown). The holder 8 and end cap 4 each have radially extending tangs 10, 12 which are seated in cutouts 13 in the end 6 of the casing 2. The end 6 of the casing 2 is swaged over to hold the end cap 4 and holder 8 in place.

Two first terminals 14 for connection of a power supply to the motor extend axially away from the end cap 4 and are insulated from the end cap by the holder 8.

The end cap 4 has a boss 16 which houses a bearing (not shown) supporting a shaft 18 of the motor.

Adapting means for changing the terminal configuration of the motor, that is the position and/or shape of the terminals 14, comprises a plastics support 20, a pair of conductors 22 and a pair of prong-like terminals 24.

Support 20 comprises an annul us of plastics material having a central aperture 26 which fits over the boss 16. A plurality of resilient nibs 28 (one is shown in figure 2) are positioned to hook under the edge 30 of apertures 32 in the end cap 4 to hold the support 20 on the end cap. A pin 34 is received in an aperture 36 in the end cap to further locate the support.

Each conductor 22 lays in a recess 38 in the upper surface 40 of the support 20. The conductors comprise a first end 42 having an aperture 44 for receiving an end 46 of a second terminal 24, and a second end 48 for making contact with a first terminal 14.

Referring to Figure 2, the first ends 42 project under an overhanging lip 50 formed on the support 22 and across a gap 52 in the support. Lip 50 has an aperture 54 which snugly receives the stem 56 of terminal 24. Stem 56 is of slightly larger diameter than end 46 so as to rest on the conductor 22. The end 46 projects through the aperture 44 and is swaged over to rivet the terminal 24 to the conductor 22.

Referring to figure 3, the terminal 14 projects through an aperture 58 in the support 20 and between the legs 60 of a cutout 62 in the end 48 of conductor 22 and is folded over to bear against the end 48. A tab 64 on the end 48 is folded over to hold the terminal 14 flat against the conductor end 48.

To assemble the motor, the conductors 20 are positioned in the recesses 32, the ends 42 being slid under the overhangs 50. The ends 46 of the second terminals are inserted through aperture 54 in the overhangs 50 into the apertures 44, the stems 56 resting on the upper surface of the conductors 22.

The ends 46 are then swaygd over to form a rivet like connection, access being had from the underside of the support 22 through the gaps 52.

The support 20, conductors 22 and terminal 24 thus form a unit which can be attached to a standard motor to adapt the configuration of the terminals 14. The unit is clipped on the end cap 2, nibs 28 clipping under the lips 30 of the apertures 32 and the terminals 14 and tabs 60 being folded over to effect electrical connection from the terminals 14 to the terminals 24.

As seen in Figure 2, the end 42 of the conductor 22 is supported on either side of the aperture 44, and hence terminal 56, so that pressure on terminal 24 when installing the motor will not bend the conductor 22 and cause a risk of the terminal 24 shorting with the motor casing. The overhang 50 further stabilises the terminal 56 against lateral movement.

Various modifications may be made to the described embodiment and it is desired to include all such modifications as fall within the scope of the accompanying claims.

Claims

1. A fractional horsepower PMDC motor comprising an end cap and a first terminal, and adapting means for adapting the terminal configuration of the motor, said adapting means comprising an electrically insulating support arranged to be carried on said end cap, a conductor carried by said support and arranged to electrically contact said first terminal, and a second terminal joined to said conductor, wherein said conductor bridges a gap in the support and the second terminal is joined to said conductor in the region of said gap.

2. A motor as claimed in claim 1, wherein the conductor is supported on an upper surface of the support, a lower surface of the support facing the motor end cap, and said conductor passes beneath a portion of the support having an aperture therein through which the second terminal projects, thereby to support the second terminal against lateral movement.

3. A motor as claimed in claim 1 or 2, wherein the first terminal is folded over the conductor to make electrical contact therewith and a portion of the conductor is folded over the first terminal to hold said first terminal and conductor in contact with each other.

4. A motor as claimed in claim 1, 2 or 3, wherein the second terminal is rivetted to the support.

5. A motor as claimed in any one of claims 1 to 4, comprising two first terminals, two conductors and two second terminals.

6. A motor as claimed in any one of claims 1 to 5, wherein the motor end cap is of metal.

7. Adapting means for adapting the terminal configuration of an electric motor, said adapting means comprising an electrically insulating support arranged to be mounted on an end cap of the motor, a conductor on the support and arranged for making electrical contact with a terminal of the motor, and a second terminal attached to the conductor, wherein the second terminal is attached to the conductor at a region which bridges a gap in the support.

8. A fractional horsepower permanent magnet direct current motor substantially as hereinbefore described with reference to the accompanying drawings.