US 6973762 B2
A device to lift a throat of an envelope to spread open the envelope. The device comprises a suction cup mounted to a pitching arm; a hook movably mounted adjacent to the suction cup; means for lowering the pitching arm to allow the suction cup to seal with the throat with a suction force, and raising the pitching arm to allow the suction cup to lift the throat; and an actuation device for placing the hook under the throat after the throat has been lifted by the suction cup so as to mechanically maintain the lifted position of the throat. Accordingly, the method of maintaining the lifted position of a throat includes the steps of: 1) positioning the suction cup over the throat; 2) pressing the suction cup against the throat to seal with the throat; 3) raising the suction cup to lift the throat; and 4) placing the hook under the lifted throat to mechanically maintain the lifted position of the throat. It is preferred that the suction force can be provided by a vacuum pump, and preferably a piston operated vacuum pump.
1. A device for lifting a throat of an envelope to a lifted position, comprising:
a suction device sealed against the throat by a suction force within the suction device;
a mechanical device located adjacent said suction device;
first means for moving the suction device so as to lift the throat to the lifted position;
second means for placing the mechanical device under the throat after the throat has been lifted to the lifted position by the suction device so as to mechanically maintain the throat at the lifted position at times when the suction force is removed to permit the insertion of materials into the envelope; and
a pitching arm upon which the suction device is mounted, wherein the first means lowers the pitching arm so that the suction device contacts and seals against the throat and raises the pitching arm so that the suction device lifts the throat to the lifted position;
wherein the mechanical device comprises a finger movably connected to the pitching arm, the finger having a hook which is located adjacent to the suction device and which is movable between a first position under the suction device and a second position removed from the suction device, and wherein the second means is used to move the finger whereby the hook is placed in the first position after the throat has been lifted to the lifted position thereby mechanically maintaining the throat at the lifted position at times when the suction force is removed.
2. The device of
3. The device of
This is a continuation of application Ser. No. 09/408,054, U.S. Pat. No. 6,425,223, filed Sep. 29, 1999, titled Method and Device for Maintaining the Opening Position of an Envelope.
The present invention relates generally to a document inserting machine and, more specifically, an envelope opening device in the inserting machine.
In an inserting machine for mass mailing, there is a gathering section where enclosure material is gathered before it is inserted into an envelope. This gathering section is sometimes referred to as a chassis subsystem, which includes a gathering transport with pusher fingers rigidly attached to a conveyor belt and a plurality of enclosure feeders mounted above the transport. If the enclosure material contains many documents, these documents must be separately fed from different enclosure feeders. After all the released documents are gathered, they are put into a stack to be inserted into an envelope in an inserting station. Envelopes are separately fed to the inserting station, one at a time, and each envelope is placed on a platform facing down with its flap flipped back all the way. At the same time, mechanical fingers or a vacuum suction device are used to hold the front face of the envelope on the platform while the throat portion of the back face of the envelope is pulled upward to open the envelope. The stack of enclosure material is than automatically inserted into the opened envelope.
In the past, vacuum suction has been used to open envelopes as a precursor to material insertion. For example, U.S. Pat. No. 5,052,168 (DeWitt el al.) discloses a method and an apparatus to spread open an envelope where two suction cups are placed on the opposing faces of the envelope. An air flow is drawn through two respective suction arms to produce a negative air pressure to allow the suction cups to seal with the respective faces of the envelope. The suction cups are then moved away from each other in order to spread open the envelope. A vacuum pump, along with a plurality of bleed valves, release valves and dump valves, is used to produce the necessary suction force. In the method disclosed by DeWitt et al, only one suction cup is used to pick up the throat of the envelope. In general, it is preferred that a number of suction cups be positioned around the throat section of the envelope in order to spread open the envelope. The number of suction cups used is usually determined by the width of the envelope. As shown in
Like other similar designs, the method disclosed by DeWitt et al. uses a constantly running vacuum pump to draw the air flow in order to open and maintain the opening position of envelopes for either material insertion or extraction. The various valves in the vacuum manifold are opened or closed whenever vacuum is required for the suction cups to pick up the faces of the envelope. Typically, a large A.C. vacuum pump is required to produce the necessary suction force. The disadvantages of using such a vacuum pump in an inserting machine include:
1) energy is wasted because the power consumption of a large pump is high;
2) energy is wasted because the pump is kept running even when it is not used to open an envelope; and
3) the noise levels generated by the constantly running pump are high.
It is advantageous to provide a method and a device for opening envelopes in an inserter station wherein the vacuum or low air pressure needed for suction is produced intermittently for a short period of time and, after the throat is opened, the envelope opening position can be mechanically maintained as long as it is required without relying on the suction force within the suction cup.
The device to spread open an envelope having a throat, according to the present invention, includes: a pitching arm; a suction cup attached to the pitching arm; a hook located adjacent to the suction cup; a pitching device for pitching the pitching arm in a first direction to cause the suction cup to contact and to seal with the throat by a suction force within the suction cup, and for pitching the pitching arm in a second direction to cause the suction cup to lift the throat to spread open the envelope into an opening position; and an actuator for causing the hook to be placed under the throat after the throat has been lifted by the suction cup so as to mechanically maintain the envelope in the opening position at times when the suction force is removed.
Accordingly, the method to spread open an envelope having a throat, wherein a suction cup is used to lift the throat to spread open the envelope into an envelope opening position, includes the steps of: 1) positioning the suction cup over the throat of the envelope; 2) moving the suction cup into contact with the throat; 3) lifting the throat by the suction device to spread open the envelope into the envelope opening position; and 4) placing a mechanical device under the throat so as to maintain the envelope opening position.
The above method further includes the step of removing the mechanical device from the throat, releasing the throat from the suction cup, and preparing the device for opening another envelope in the next cycle.
The method and device for maintaining the opening position of an envelope will become apparent upon reading the description taken in conjunction with
As shown in
With the present invention, the vacuum or low air pressure in the suction cup 20 is only needed for a short time, just long enough to pickup and lift the envelope throat 104 and to place the hook 34 under the envelope throat 104. After that, the envelope opening position is mechanically maintained by keeping the solenoid 40 energized.
It should be noted that the illustrations in
When it is time to remove the suction force, the cam 150 is again rotated by motor 160 in order to push the piston 136 toward the inlet 134 to minimize the volume of the air chamber 132, resetting the vacuum pump 130 to its recharged position.
It should be noted that although the envelope opening devices depicted in
Although the invention has been described with respect to preferred versions and embodiments thereof, it will be understood by those skilled in the art that the foregoing and various other changes, omissions and deviations in the form and detail thereof may be made without departing from the spirit and scope of this invention.