GB1577924A

GB1577924A - Hand grip for a portable electric appliance

Info

Publication number: GB1577924A
Application number: GB27211/76A
Authority: GB
Original assignee: Arrow Hart Europe Ltd
Current assignee: Arrow Hart Europe Ltd
Priority date: 1977-06-29
Filing date: 1977-06-29
Publication date: 1980-10-29

Description

(54) A HAND GRIP FOR A PORTABLE ELECTRIC APPLIANCE (71) We, ARROW HART (EUROPE) LIMITED, a British Company, of Plymbridge Road, Estover, Plymouth PL6 7PN, 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 a hand grip for a portable electric appliance, for example a lawn mower, lawn-edge trimmer, hedge cutter or vacuum cleaner. The invention also relates to a handle assembly provided with such a hand grip.

According to one aspect of the invention a hand grip for a portable electric appliance comprises a casing housing a switch means for the electric appliance, said casing comprising a tubular part which is removably connectible to a tubular member of the electric appliance by resilient catch means secured to the casing.

According to a further aspect of the invention a handle assembly for a portable electric appliance comprises a rigid, elongate tubular member, and a hand grip comprising a casing housing a switch means for the electric appliance, said casing comprising a tubular part which is removably connectible to said tubular member by resiliently interengageable first and second catch means associated with said casing and said tubular member, respectively.

In a preferred embodiment of the handle assembly according to the invention, said first catch means comprises at least one resilient arm secured to the casing, the first catch means being surrounded by the tubular part and positionable within said tubular member to resiliently interengage with said second catch means positioned adjacent an open end of said tubular member. The or each arm may have locating means cooperable with the second catch means to prevent relative movement between the hand grip and the tubular member in a first axial direction of said tubular part, the or each locating means being movable out of cooperation with the second catch means, on resilient movement of the or each arm, to permit relative movement between the hand grip and the tubular member in said first axial direction, thereby allowing detachment of the hand grip from the tubular member. Suitably the tubular part is provided with inwardly-projecting abutment means spaced from the open end of said tubular part, abutment of the open end of the tubular member or said second catch means against said abutment means preventing relative movement between the hand grip and the tubular member in a second axial direction opposite to said first axial direction. Typically the tubular member and the tubular part are of circulr cross-section, the tubular member being coaxially positioned inside said tubular part.

The second catch means may consist of one or more inwardly-projecting indentations in the wall of said tubular member. In particular the first catch means may comprise two resilient arms, the locating means of the two arms being cooperable with a diametriclly opposed and inwardlyprojecting pair of indentations constituting said second catch means. In this case, each of the locating means suitably comprise a radially outwardly-directed projection having a groove; opening into its radially outwardly-facing surface, which cooperates with its respective indentation. Each groove suitably has an axially-facing end wall which abuts against an axially-facing surface of its respective cooperating indentation to prevent relative movement between the hand grip and the tubular member in said first axial direction, movement towards each other of said two resilient arms causing the grooves to be moved out of cooperation with their respective indentations. This movement of the two arms towards each other may be effected by turning the tubular part relative to said tubular member.

Alternatively, the second catch means may comprise a sleeve fixed inside the tubular member at, or adjacent to its open end, the or each locating means having an axially facing abutment surface which abuts against a flat, axially facing end surface of the sleeve, to prevent said relative movement between the hand grip and the tubular member in said first axial direction. One or more access holes may be provided in the wall of the tubular member to permit the insertion of a tool (e.g. a screwdriver) therethrough to move the or each resilient arm in a direction perpendicular to the axial direction to move the abutment surface and the flat end surface out of axial alignment.

Whilst the flat end surface and the abutment surface are moved out of axial alignment it is possible to detach the hand grip from the tubular member. Inwardly-projecting indentations, which cooperate with engaging means in the sleeve, may be provided in the wall of the tubular member to secure the sleeve to the tubular member.

The handle assembly may include a plug member connected or connectible to one end of a supply lead and capable of being plugged into the hand grip to make electrical contact with part of the switch means.

The invention will now be described, by way of example, with reference to the drawings accompanying the Provisional specification, in which: Figure 1 is a section through one embodiment of a handle assembly according to the invention, Figure 2 is a section on the line II-II of Figure 1, Figure 3 is an enlarged view of a portion of Figure l, Figure 4 is a section on the line IV-IV of Figure 3, Figure 5 is a section through part of another embodiment of a handle assembly according to the invention, Figure 6 is a different sectional view of the part of the handle assembly shown in Figure 5, and Figure 7 is a section on the line VII-VII of Figure 6.

Figure 1 shows a handle assembly, generally designated by the reference numeral 1.

of an electrically-operated lawn mower.

This handle assembly comprises a metal tube 2 of circular cross-section. a handgrip 3 detachably connected to an open end 4 of the tube 2. and a plug member 5 removably inserted in the handgrip 3. The handgrip 3 comprises two parts 3a and 3b (see Figure 2) of generally U-cross-section and made of electrically insulating material which are either hald together by screws (not shown) or welded, e.g. ultrasonically, together to define the casing of the handgrip 3. Within the casing there is housed an insert, generally designated by the reference numeral 6, and a switch comprising two fixed contact blades 7 and 8 mounted on a rib 9 of electrically-insulating material integrally formed with casing part 3a, and two further fixed contact blades 10 and 11 mounted on a further rib 12 of electrically-insulating material also integrally formed with the casing part 3a. A switch-actuating member 13, carrying a pair of metallic bridging contacts 14 and 15, is actuable by finger pressure against the resistance of a spring (not shown) to position the bridging contacts 14 and 15 in electrical and mechanical contact with the terminal members 7, 10 and the terminal members 8, 11, respectively.

The insert 6 consists of a head portion 16 and a shank portion 17 integrally formed therewith. The shank portion 17 comprises a pair of resilient arms 18, 19 which extend into a tubular end part 20 of the hand grip 3.

Radially-outwardly projecting portions 21, 22 are integrally formed at the free end of the arms 18, 19, respectively. Grooves 23, 24, of substantially V-cross-section open into the radially-outwardly facing surface of the portions 21, 22, respectively; one end of the grooves 23, 24 being open and the opposite end of the grooves 23, 24 having a flat, axially-facing abutment surface 25, 26, respectively. Seated in the grooves 23, 24 are radially-inwardly-projecting pressings 27, 28, respectively, formed in diametrically opposed portions of the metal tube 2, adjacent its open end 4. Each of the pressings 27, 28 has an axially-facing abutment surface 29, 30, respectively, which abuts against the abutment surface 25, 26, respectively, to prevent axial movement of the tube 2, in the direction indicated by the arrow A, relative to the tubular end part 20.

Movement of the tube 2 relative to the end part 20 in the direction opposite to that indicated by the arrow A is prevented by abutment of the open end 4 of the tube 2 against radially-inwardly-projecting flanges 31 integrally formed with the casing parts 3a and 3b at the axially-inner end of the tubular end part 20. The shank portion 17 of the insert 6 passes through an opening 32 defined by the flanges 31. The opening 32 is of non-circular cross-section, e.g. rectangular, to prevent turning of the insert 6 therein.

In order to detach the hand grip 3 from the metal tube 2, the hand grip 3 is first turned through approximately 90" relative to the tube 2 from the position shown in the drawings. There is an initial resistance to this turning movement since pressings 27, 28 are seated in the grooves 23, 24, respectively. However, during the initial part of the turning movement, the arms 21 and 22 are resiliently moved towards each other and the pressings 27, 28 are moved out of the grooves 23, 24, respectively. Once the pressings 27, 28 have been moved fully out of the grooves, 23, 24, respectively, the metal tube 2 can be moved axially relative to the end part 20 in the direction indicated by the arrow A to detach the tube 2 from the hand grip 3. Attachment of the tube 2 to the hand grip 3 can be easily performed by following the procedure outlined above in reverse.

An electric cable 82, having a pair of electric conductors 33 and 34 connected to terminals at the ends of the fixed contact blades 7 and 8, respectively, enters into the hand grip 3 through an opening 35 and is clamped in the head portion 16. As shown in Figures 3 and 4, the head portion 16 is in the form of an open box having a pair of spaced-apart, parallel side walls 36, 37, a pair of spaced-apart, parallel end walls 38, 39, a bottom 80 and an open top 81.

Openings 40 and 41 are provided in the walls 36 and 38, respectively, and serve to locate opposite ends of the part 42 of the cable 82 positioned within the head portion 16. A curved, internal partition wall 43 partly obstructs a direct cord path between the openings 40 and 41 and defines one side of the shortest cord path between the two openings 40 and 41. A resilient blade or finger 44, integrally formed with, and projecting from, the end wall 39 presses the cable part 42 against a substantially convexly-curved surface 45 of the wall 43, thereby resiliently gripping or clamping the cable 82 in the head portion 16. The surface 45 is provided with means for deterring movement of the cable part 42 with respect to the wall 43 at least in one direction along the shortest cord path. In Figures 1, 3 and 4, the deterring means comprises saw teeth 46, although other types of deterring means, such as ribs (not shown) could be used. The finger 44 is shown positioned so as to form an acute angle a with the cable part 42. This acute angle, together with the inclination of the saw teeth 46, deters movement of the cable 82 through the head portion 16 in the direction indicated by the arrow B (Figure 3).

Prior to securing the two casing parts 3a, 3b together, the resilient finger 44 may be manually moved out of contact with the cable part 42 thereby enabling the cable 82 to be freely moved through, and accurately positioned in, the head portion 16. In this case, access to the finger 44 is gained through the open top 81 of the head portion 16. If the two casing parts 3a, 3b are subsequently secured together, it is not possible thereafter to readjust the position of the cable 82 in the head portion 16.

However, if the two casing parts 3a, 3b are subsequently detachably secured together e.g. screwed or bolted together, it is possible thereafter to separate the casing parts enabling either readjustment of the cable position in the head portion 16 or the removal of the cable 82 and replacement by another cable.

The insert 6 is suitably moulded in one piece from thermoplastics material. A rectangular aperture 47 is provided in the bottom 80 of the head portion 16 for the insertion of a tool during the moulding process to enable the forming of the underside 83 of the finger 44. The underside 83 of the finger 44 is thus spaced from the bottom of the head portion 16.

The plug member 5 comprises a pair of contact members 50 and 51 which make electrical and mechanical contact with the terminal members 10 and 11, respectively.

Electrical conductors 52, 53 of an electric cable 54 are securely connected to the contact members 50, 51, respectively. A cable clamp for the cable 54 is schematically shown at 55. In practice this cable damp may be of similar construction to the head portion 16 described hereinbefore. A thermal cut-out (not shown) may be installed in the plug member 5.

Another embodiment of the handle assembly is shown in Figures 5, 6 and 7 (where appropriate similar reference numerals have been used to identify similar parts in the embodiment shown in Figure 1 to 4 and the embodiment shown in Figures 5 to 7).

In the handle assembly shown in Figures 5 to 7, a sleeve 100 is positioned inside the end 4 of the metal tube 2. The sleeve 100 has radially-outwardly-projecting portions 101 (see Figure 5) and 102 (see Figure 6) at its opposite ends which provide axially-facing abutment surfaces 103 and 104, respectively. The end 4 of the tube 2 abuts against the surface 103 and prevents further axial movement of the sleeve 100, relative to the tube 2, in the direction indicated by the arrow X.

Radially-inwardly projecting and diametrically opposed pressings 105, 106 are provided in the tube 2, adjacent its end 4, and abut against the surface 104 to prevent axial movement of the sleeve 100, relative to the tube 2, in the opposite direction to that indicated by the arrow X.

The sleeve 100 has a non-circular opening 107 therein through which the shank portion 17 of the insert 6 passes. The shank portion 17 consists of a single, resilient arm 108 of rectangular cross-section having a radiallyoutwardly projecting portion 109 integrally formed therewith. The portion 109 has a pair of abutment surfaces 110 and 111 which abut against a portion 112 of the axiallyfacing end face of the sleeve 100 and a portion 113 of the radially inwardly-facing surface of the sleeve 100, respectively. The abutment of the surface 110 with the portion 112 prevents movement of the tube 2 and sleeve 100 axially in the direction indicated by the arrow X relative to the tubular end part 20. The axially-facing end face of the portion 101 abuts against the flanges 31 and prevents movement of the tube 2 and sleeve 100 axially, in the direction opposite to that indicated by the arrow X, relative to the tubular end part 20.

The tube 2, is detached from the handgrip 3 by resiliently moving the arm 108 so that the surface 111 is moved away from the portion 113 and the surface 110 is moved out of alignment with the portion 112. The tube 2 and sleeve 100 can then be axially moved in the direction X relative to the end part 20 so that it is detached from the handgrip 3.

An access hole 114 is provided in the wall of the tube 2 for the insertion of the end of a tool, e.g. a screwdriver, to resiliently move the arm 108 so as to enable detachment of the tube 2 from the handgrip 3.

Since, in the embodiment of the handle assembly shown in Figures 5 to 7, the handgrip 3 does not have to be turned, relative to the tube 2, to effect release of the handgrip 3 from the tube 2, it is not essential for the tube 2 to be of circular cross-section, and the invention is intended to embrace a handle assembly having a non-circular (e.g.

square) cross-section. The tube 2 may also be made of a non-metallic material (e.g.

plastics material).

It is also possible for the resilient catch means to be formed integrally with the casing instead of being in the form of an insert which is retained in the casing by the casing parts when the latter are secured together.

It should be realised that in other embodiments (not shown) of a handle assembly according to the invention, resilient means (e.g. a resilient arm or arms) may be mounted in the tube 2 for interengagement with catch means (e.g. an abutment or abutments) on the casing.

In our co-pending APplication No. 27212/ 76 (Serial No. 1577925) there is described a cord clamp having features similar to the cord clamp provided by the insert 6 of the handle assembly hereinbefore described.

WHAT WE CLAIM IS: 1. A hand grip for a portable electric appliance comprising a casing housing a switch means for the electric appliance. said casing comprising a tubular part which is removably connectible to a tubular member of the electric appliance by resilient catch means secured to the casing.

2. A hand grip according to claim 1. in which the casing consists of two or more parts secured together, and the catch means is in the form of a separate insert which is retained within the casing by the casing parts when the latter are secured together.

3. A handle assembly for a portable electric appliance comprising a rigid, elongate tubular member, and a hand grip comprising a casing housing a switch means for the electric appliance, said casing comprising a tubular part which is removably connectible to said tubular member by resiliently interengageable first and second catch means associated with said casing and said tubular member, respectively.

4. A handle assembly according to claim 3, in which said first catch means comprises at least one resilient arm secured to the casing, the first catch means being surrounded by the tubular part and positionable within said tubular member to resiliently interengage with said second catch means positioned adjacent an open end of said tubular member.

5. A handle assembly according to claim 4, in which the or each arm has locating means cooperable with the second catch means to prevent relative movement between the hand grip and the tubular member in a first axial direction of said tubular part, the or each locating means being movable out of cooperation with the second catch means, on resilient movement of the or each arm, to permit relative movement between the hand grip and the tubular member in said first axial direction, thereby allowing detachment of the hand grip from the tubular member.

6. A handle assembly according to claim 5, in which the tubular part is provided with inwardly-projecting abutment means spaced from the open end of said tubular part, abutment of the open end of the tubular member or said second catch means against said abutment means preventing relative movement between the hand grip and the tubular member in a second axial direction opposite to said first axial direction.

7. A handle assembly according to any of claims 4 to 6, in which the tubular member and the tubular part are of circular cross-section, the tubular member being coaxially positioned inside said tubular part.

8. A handle assembly according to any of claims 4 to 7, in which the second catch means consists of one or more inwardlyprojecting indentations in the wall of said tubular member.

9. A handle assembly according to claim 8, in which the first catch means comprises two resilient arms, the locating means of the two arms being cooperable with a diametrically opposed and inwardly-projecting pair of indentations constituting said second catch means.

10. A handle assembly according to claim 9, in which each of the locating means comprises a radially outwardly-directed pro

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

Claims

**WARNING** start of CLMS field may overlap end of DESC **. surface of the sleeve 100, respectively. The abutment of the surface 110 with the portion 112 prevents movement of the tube 2 and sleeve 100 axially in the direction indicated by the arrow X relative to the tubular end part 20. The axially-facing end face of the portion 101 abuts against the flanges 31 and prevents movement of the tube 2 and sleeve 100 axially, in the direction opposite to that indicated by the arrow X, relative to the tubular end part 20. The tube 2, is detached from the handgrip 3 by resiliently moving the arm 108 so that the surface 111 is moved away from the portion 113 and the surface 110 is moved out of alignment with the portion 112. The tube 2 and sleeve 100 can then be axially moved in the direction X relative to the end part 20 so that it is detached from the handgrip 3. An access hole 114 is provided in the wall of the tube 2 for the insertion of the end of a tool, e.g. a screwdriver, to resiliently move the arm 108 so as to enable detachment of the tube 2 from the handgrip 3. Since, in the embodiment of the handle assembly shown in Figures 5 to 7, the handgrip 3 does not have to be turned, relative to the tube 2, to effect release of the handgrip 3 from the tube 2, it is not essential for the tube 2 to be of circular cross-section, and the invention is intended to embrace a handle assembly having a non-circular (e.g. square) cross-section. The tube 2 may also be made of a non-metallic material (e.g. plastics material). It is also possible for the resilient catch means to be formed integrally with the casing instead of being in the form of an insert which is retained in the casing by the casing parts when the latter are secured together. It should be realised that in other embodiments (not shown) of a handle assembly according to the invention, resilient means (e.g. a resilient arm or arms) may be mounted in the tube 2 for interengagement with catch means (e.g. an abutment or abutments) on the casing. In our co-pending APplication No. 27212/ 76 (Serial No. 1577925) there is described a cord clamp having features similar to the cord clamp provided by the insert 6 of the handle assembly hereinbefore described. WHAT WE CLAIM IS:

1. A hand grip for a portable electric appliance comprising a casing housing a switch means for the electric appliance. said casing comprising a tubular part which is removably connectible to a tubular member of the electric appliance by resilient catch means secured to the casing.

jection having a groove, opening into its radially outwardly-facing surface, which cooperates with its respective indentation.

11. A handle assembly according to claim 10, in which each groove has an axially-facing end wall which abuts against an axially-facing surface of its respective cooperating indentation to prevent relative movement between the hand grip and the tubular member in a first axial direction, movement towards each other of said two resilient arms causing the grooves to be moved out of cooperation with their respective indentations.

12. A handle assembly according to claim 11, in which movement of the two arms towards each other is effected by turning the tubular part relative to said tubular member.

13. A handle assembly according to claim 5 or 6 or claim 7 when dependent upon claim 5 or 6, in which the second catch means comprises a sleeve fixed inside the tubular member at, or adjacent to its open end, the or each locating means having an axially facing abutment surface which abuts against a flat, axially facing end surface of the sleeve, to prevent said relative movement between the hand grip and the tubular member in said first axial direction.

14. A handle assembly according to claim 13, in which the wall of the tubular member is provided with one or more access holes to permit the insertion of a tool therethrough to move the or each resilient arm in a direction perpendicular to the axial direction to move the abutment surface and the flat end surface out of axial alignment enabling the hand grip to be detached from the tubular member.

15. A handle assembly accordng to claim 13 or 14, in which inwardly-projecting indentations, which cooperate with engaging means in the sleeve, are provided in the wall of the tubular member to secure the sleeve to the tubular member.

16. A handle assembly according to any one of claims 1 to 15, including a plug member connected or connectible to one end of a supply lead and capable of being plugged into the hand grip to make electrical contact with part of the switch means.

17. A handle assembly according to any of claims 3 to 16, in which the casing consists of two or more parts secured together.

18. A handle assembly according to claim 17, in which the first catch means comprises a separate insert which is retained within the casing by the casing parts when the latter are secured together.

19. A handle assembly according to any of claims 3 to 17, in which the first catch means is formed integrally with said casing or casing parts.

20. A handle assembly constructed and arranged substantially as herein described with reference to, and as illustrated in, Figures 1 and 2 or Figures 5, 6 and 7 of the drawings accompanying the provisional specification.