GB2172227A

GB2172227A - Hydraulic wedge unit

Info

Publication number: GB2172227A
Application number: GB08506646A
Authority: GB
Inventors: Brian Hays
Original assignee: SERMEC ENGINEERING Ltd
Current assignee: SERMEC ENGINEERING Ltd
Priority date: 1985-03-14
Filing date: 1985-03-14
Publication date: 1986-09-17
Also published as: GB8506646D0; GB2172227B

Abstract

The unit comprises two pivoted arms 11, 12 and an hydraulically moved wedge 15 urged between the arms to separate them. The hydraulic piston-cylinder 18, connected to the wedge, is operated from a pump via a solenoid valve controlled by a switch on a handle extending from the rear of the cylinder to a bracket at the forward ends. The unit is for removing casting sprues or splitting logs. <IMAGE>

Description

SPECIFICATION Hydraulic wedge unit This invention relates to a wedge unit for effecting a prising force especially for the removal of sprues from castings.

After a casting has been produced the resulting metal inflows known as sprues require to be broken off as cleanly as possible.

An object of the invention is to provide a device by which a shear force can be applied to the base or proximal end of the sprue to effect a clean break.

According to the invention there is provided a body portion, two arms pivotally mounted on said body portion and extending generally in one direction, a wedge movable in said one direction between said arms to move the latter apart and in the apposite direction to permit movement of said arms towards each other and means for effecting movement of said wedge to drive the arms apart. Preferably a hydraulic piston and cylinder device is provided to actuate said wedge in both directions.

An embodiment of the invention will not be described by way of example with reference to the accompanying drawing in which: Figure 1 is a plan view of the wedge unit with the handle and operating switch omitted, and Figure 2 is a side elevation with the handle and operating switch in chain lines.

The wedge unit comprises a body portion 10 to which is pivotally connected a pair of arms 11, 12 by means of pairs of links 13, 14. The arms 11, 12 extend from the body generally in one direction and are each shaped in tapering manner.

Sandwiched between the two arms 11, 12 is a wedge 15 having a 10 degree taper. The rear end of the wedge is provided with a vertical slot 16 into which engages the leading end 1 7a of a piston 17 of a hydraulic piston and cylinder device 18 mounted on the body poriton 10. The piston end 17a is connected to the wedge by means of a pin 19 which is located in a bore 20 and passes through a bore 21 in the piston end 17a.

As shown in Fig. 1 the arms each have a taper of 5 degrees on the inside surface and an outside surface of 8 degrees relative to the centre line X.

Units may be supplied with various forms of drive means but the basic principle comprises of an oil tank and a pump (not shown). The pump is driven by an electric or air motor.

The output is passed through a pressure relief valve and then a solenoid operated spool valve to the hydraulic cylinder 18 via two hydraulic hoses 21, 22.

The motor is controlled by a standard ON/OFF starter. Voltage is stepped down to 110 Volts A.C. by means of a transformer.

This voltage is used to switch the directional solenoid valve this being controlled by a double button hand switch 25.

In Fig. 2 the switch 25 may be attached to the wedge unit to form a handle. The switch 25 is in this case supported at one end by a plate 26 attached to the rear end of the cylinder 18 and at the other end by a bracket 27 formed of wire and attached by screws 28 to a plate 29 secured to the body portion 10 by a block 30.

As a further handle a vertical rod 31 may be attached to the plate 29. An eye 32 on said rod 31 may be used to support the wedge unit on a hook when the unit is not in use.

A spring 33 is connected to the two arms to assist the return of the arms to a rest position.

In use the wedge unit is placed between the sprues the piston and cylinder 18 activated.

As the wedge advances a shearing force is applied at the base of the sprue and on reaching a particular force the sprue breaks cleanly.

The wedge is then withdrawn by the cylinder and returns to its start position assisted by the spring 33.

The speed of operation of the unit will vary depending upon the requirements of the particular component to be worked, e.g. 3 seconds fully out and 2 seconds for return.

The wedge unit may have various uses e.g.

splitting logs along the grain.

When the wedge unit is used to break two sprues it is moved so that its effective width suits the gap between the sprues. This ensures that a minimum distance is moved prior to the break.

If only one sprue needs breaking the component is dropped into a jig such that the wedge unit may be operated between the solid part of the jig and the sprue to be removed. Jigs for this are very simple in design and construction and are made to suit each individual component to be worked.

1. An hydraulic wedge device comprising a body portion, two arms pivotally mounted on said body portion and extending generally in one direction, a wedge movable in said one direction between said arms to move the latter apart and in the opposite direction to permit movement of said arms towards each other and hydraulic means for effecting movement of said wedge to drive the arms apart.

2. An hydraulic wedge device as claimed in claim 1 wherein said hydraulic means comprise a cylinder attached to the body, a piston operating in the cylinder and having one end fixed to the rear end of the wedge, and a pump to supply fluid to the cylinder.

3. An hydraulic wedge device as claimed in claim 2 wherein the body extends transversely on both sides of the cylinder and the ends of

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

Claims

**WARNING** start of CLMS field may overlap end of DESC **. SPECIFICATION Hydraulic wedge unit This invention relates to a wedge unit for effecting a prising force especially for the removal of sprues from castings. After a casting has been produced the resulting metal inflows known as sprues require to be broken off as cleanly as possible. An object of the invention is to provide a device by which a shear force can be applied to the base or proximal end of the sprue to effect a clean break. According to the invention there is provided a body portion, two arms pivotally mounted on said body portion and extending generally in one direction, a wedge movable in said one direction between said arms to move the latter apart and in the apposite direction to permit movement of said arms towards each other and means for effecting movement of said wedge to drive the arms apart. Preferably a hydraulic piston and cylinder device is provided to actuate said wedge in both directions. An embodiment of the invention will not be described by way of example with reference to the accompanying drawing in which: Figure 1 is a plan view of the wedge unit with the handle and operating switch omitted, and Figure 2 is a side elevation with the handle and operating switch in chain lines. The wedge unit comprises a body portion 10 to which is pivotally connected a pair of arms 11, 12 by means of pairs of links 13, 14. The arms 11, 12 extend from the body generally in one direction and are each shaped in tapering manner. Sandwiched between the two arms 11, 12 is a wedge 15 having a 10 degree taper. The rear end of the wedge is provided with a vertical slot 16 into which engages the leading end 1 7a of a piston 17 of a hydraulic piston and cylinder device 18 mounted on the body poriton 10. The piston end 17a is connected to the wedge by means of a pin 19 which is located in a bore 20 and passes through a bore 21 in the piston end 17a. As shown in Fig. 1 the arms each have a taper of 5 degrees on the inside surface and an outside surface of 8 degrees relative to the centre line X. Units may be supplied with various forms of drive means but the basic principle comprises of an oil tank and a pump (not shown). The pump is driven by an electric or air motor. The output is passed through a pressure relief valve and then a solenoid operated spool valve to the hydraulic cylinder 18 via two hydraulic hoses 21, 22. The motor is controlled by a standard ON/OFF starter. Voltage is stepped down to 110 Volts A.C. by means of a transformer. This voltage is used to switch the directional solenoid valve this being controlled by a double button hand switch 25. In Fig. 2 the switch 25 may be attached to the wedge unit to form a handle. The switch 25 is in this case supported at one end by a plate 26 attached to the rear end of the cylinder 18 and at the other end by a bracket 27 formed of wire and attached by screws 28 to a plate 29 secured to the body portion 10 by a block 30. As a further handle a vertical rod 31 may be attached to the plate 29. An eye 32 on said rod 31 may be used to support the wedge unit on a hook when the unit is not in use. A spring 33 is connected to the two arms to assist the return of the arms to a rest position. In use the wedge unit is placed between the sprues the piston and cylinder 18 activated. As the wedge advances a shearing force is applied at the base of the sprue and on reaching a particular force the sprue breaks cleanly. The wedge is then withdrawn by the cylinder and returns to its start position assisted by the spring 33. The speed of operation of the unit will vary depending upon the requirements of the particular component to be worked, e.g. 3 seconds fully out and 2 seconds for return. The wedge unit may have various uses e.g. splitting logs along the grain. When the wedge unit is used to break two sprues it is moved so that its effective width suits the gap between the sprues. This ensures that a minimum distance is moved prior to the break. If only one sprue needs breaking the component is dropped into a jig such that the wedge unit may be operated between the solid part of the jig and the sprue to be removed. Jigs for this are very simple in design and construction and are made to suit each individual component to be worked. CLAIMS

3. An hydraulic wedge device as claimed in claim 2 wherein the body extends transversely on both sides of the cylinder and the ends of the body are attached, each by a link, to the two arms respectively, the arms being also connected by a tension spring.

4. An hydraulic wedge device as claimed in claim 2 or 3 wherein the pump is driven by a motor, the pump output is passed through a pressure relief valve and a solenoid operated spool valve to the cylinder, and the solenoid valve is controlled by a switch mounted on a handle the rear end of which is supported by a plate attached to the rear end of the cylinder and the front end of which is supported by a bracket to the body.

5. An hydraulic wedge device substantially as described with reference to the accompanying drawings.