| US4495709A | 1985-01-29 | |||
| US4143463A | 1979-03-13 | |||
| US3896554A | 1975-07-29 | |||
| DE2907009A1 | 1980-08-28 |
| 1. | The rear support 4 tilts the steel rule at an angle to the workpiece 5. tilting of the steel rule reduces the area of the steel rule in contact wi the workpiece. |
| 2. | The downward force FI. applied by hand to the cutterguard increases t pressure per square C/M onto the workpiece 5 via the steel rule. |
| 3. | Th increased pressure helps reduce slip while using the steel rule as a guide f a cutter. |
| 4. | 2 The top surface 1 is long enough to allow the hand to span the cutterguard. The fingers and thumb can then apply the force downwards FI in the be position over the steel rule to obtain maximum pressure and maximum grip the workpiece. |
| 5. | Fig.2 Section AA shows the finger shield shaped up from the top surface 1. Its position on the top surface is as far forward as possible to perm maximum downward force from the hand and yet still protect the fingers fr the cutting blade. |
| 6. | The cutterguard is fastened to the steel rule by the central clip 6. T central clip presses down on the steel rule which in turn is supported by t support 7. The support 7 runs longitudinally from the central clip 6 to t end support 8. The end supports 8 are there to support the rear of t ruler when a force is applied to the front edge of the ruler from t cutterguard. |
| 7. | The central clip 6 and the supports 7 also allow the ruler to slide along t cutterguard. The cutterguard can then be used as a depth guage Fig.4. SUBSTITUTE SHEET. |
1. The object of the invention is to make safer, the cutting of paper and cardboard, or any such material, when using a sharp bladed knife and a steel rule as a straight edge to guide the cutting blade.
2. T e straight edge holder and knifeguard, here after referred to as the cutterguard, is a clear plastic moulding that clips directly onto most 300mm or 12 inch long steel rules. Fig.l.
3. The cutterguard is shaped as shown in Fig.2 Section A-A to form a shield 3 to protect the fingers thumb and hand from the sharp bladed knife when cutting.
4. The cutterguard is also shaped 4 to tilt the steel ruler up at an angle to the flat workpiece 5 with the aim of improving the grip on the workpiece and reducing the possibility of slip when cutting.
The advantages of the cutterguard are:-
(1) Safer cutting by protecting fingers.
(2) Reduces slip of straight edge giving greater accuracy of cut.
(3) Can be used as a depth guage, measuring and marking aid.
(4) Makes the steel ruler easier to pick up and handle.
(5) Gives support to the steel rule when marking or scribing or cutting strips of narrow material Fig.3.
SUBSTITUTE SHEET
DESCRIPTION
5. The cutterguard is shaped to slip onto most existing steel rules 300mm o inches long. The cutterguard can be the full length of the rule or dow 200mm long Fig.l.
6. The cutterguard is best made of clear plastic, to allow a clear view of steel rule and its divisions.
7. It has a central clip 6 which applies pressure onto the top surface of steel rule 2 and presses the rule down onto supports protruding from moulding under the steel rule 7.
8. The support that runs from the central clip 6 to each end of the cutterg acts as a support when the rule is pressed down onto the workpiece. support is mainly required at the extreme ends of the cutterguard 8.
9. The cutterguard can be easily clipped on and off the steel rule. clipping on, the steel rule can be orientated to suit*, the required sid the rule to be used.
10. During use it is best to position the cutterguard in the middle of the s rule Fig.l.
11. When using as a depth guage, the cutterguard can be slid along the rul the required depth or measurement Fig.4.
12. When using the cutterguard as an aid to cutting, the rule should be pl as shown Fig.5 with the fingers positioned along the cutterguard and be the shield as shown arrows F.l pressing down firmly with fingers and t to set the steel rule at the desired position on the workpiece F2 be cutting.
' SUBSTITUTE SHEET