DESC:Fig. 2 : Shows the perspective view of the toggle linkages of the present invention improved mold clamping unit in toggle injection molding machine
Fig. 3 : Shows the side perspective view and the cross-sectional front view of the die height platen of the present invention improved mold clamping unit in toggle injection molding machine
Fig. 4 : Shows the side perspective view and the cross-sectional front view of the moving platen of the present invention improved mold clamping unit in toggle injection molding machine

Meaning of the reference numerals in the present invention
100 : a Toggle Clamping unit
101 : Toggle linkage crosshead
102 : Toggle linkages
103 : Binary links
104 : Ternary links
105 : Crosshead links
106 : Moving platen
107 : A die height platen
108 : Bushing
109 : Toggle Pin
110 : Strain Rod
111 : Controller
112 : Stationary Platen

Detailed Description of the Invention
In order to provide foregoing objects, the present invention provides An Improved Mold Clamping Unit In Toggle Injection Molding Machine. The present invention provides an invention that eliminates the possibility of fretting or corrosion; thus, it eliminates the breakdowns, which in turn extends the life of the machine; boosts the production output, reduces the maintenance cost and eliminates the extra material cost and manufacturing cost of the machine.
Referring to Fig. 1 to 4, the present improved toggle clamp for injection molding machine comprises of:
• a Toggle Clamping unit (100);
wherein,
the toggle clamping unit (100) comprises of:

• Toggle linkage crosshead (101)
• Plurality of Toggle linkages (102)
• Moving platen (106)
• A die height platen (107)
• Stationary platen (112)
• Plurality of Bushing (108)
• Plurality of Toggle Pin (109)
• Plurality of Strain Rod (110)
• Controller (111)
Wherein it uses existing Toggle linkage crosshead (101), Toggle Pin (109), Strain Rod (110), Controller (111).
In the present invention, Said toggle linkages (102) connects the die height platen (107) to the moving platen (106); wherein the toggle linkages (102) comprises of:
• Plurality of Ternary links (104)
• Plurality of Binary links (103)
• Plurality of Crosshead links (105)
Ternary Links (104) may be connected to each other through casting support and possible to have one Ternary Link (104) at top side and one Ternary Link (104) at Bottom side. This minimize Ternary Links (104) from eight to four that is two Ternary Links (104) at Top and Two Ternary Links at Bottom. However, this is expensive solution. The machining cost of both the designs are very high. Hence, Ternary Links (104) (8 ternary links) in place two numbers or four numbers. There are eight ternary links (104) used to reduce the number of toggle holes on the die height platen (107); thereby reduces the number of bushings (108) used to protect the die height platen (107). Ternary Links (104) in this invention are without Bushing. Ternary Links have fixed joint with Toggle Pins. Die Height Platen in this invention has Bushings inside (Fig. 2).

Use of these ternary links (104) reduces the complexity of manufacturing of the ternary links (104); thereby it reduces the manufacturing cost and the machining cost. It makes it possible to provide bushings (108) on the die height platen (107) rather than the ternary links (104); eliminating the need of extra bushes on the die height platen (107) as well as the ternary links (104).
Said Die height platen (107) is connected to the toggle linkage (102) such that the die height platen (107) is locked with ternary link (104) with a strain rod (110); wherein the die height platen (107) is used to tolerate the resistive force generated by the ternary links (104). There are such eight-ternary links (104) provided. The toggle pin (109) is locked with the ternary links (104). The Toggle linkage Crosshead (101) is connected to the moving platen (106) through said binary links (103); Said Binary Links (103) have Bushing (108) inside which creates bearing joint with Toggle Pins (109) connecting with Ternary Links (104). The other end of Binary Link (103) connecting with Moving Platen (106) has fixed connection with Toggle Pin (109). Binary has “fork” type design to balance force applied & reaction force on the Moving Platen. Moving Platen has Bushings inside which creates bearing joint. Binary links (103) aids the bushes (108) to be fixed with ternary links (104) without any complex changes, thereby reduces the complexity of machining and the machining cost. Manufacturing complexity of Ternary Links (104) in this invention is reduced compare to prior art thereby has reduces the cost. Binary Link (103) has “fork” type design which is more complex compare to prior art but adds more value also due to force transfer.
Said toggle linkages (102) are used for clamp opening and clamp closing movement. It is also used to apply the clamping force when the toggle clamp unit (100) is in the closed position. The Bushings (108) are attached on the bore, of the die height platen (107) without use of additional bushing; wherein the bushing (108) is placed between die height platen and toggle pin. In this invention the bushes (Bsh) are attached on the bore of the die height platen (107). Said Bushings are made of high strength bronze alloy. Said Controller (111) is provided in the toggle clamping unit (100); wherein the controller (111) controls the auto lubrication system to self-lubricate the bushings (108).
In said toggle clamping unit (100), during the mold opening and clamp closing movement, the toggle linkages takes the load of the clamping force applied on the mold. The load is maximum at the joints between the toggle linkages (102) when the toggle clamping unit (100) is closed as maximum clamping force is applied. The joint between toggle pin (109) and die height platen (107) takes this maximum load. The load reaches maximum and gets released in one clamping cycle. Normally clamping cycle completes in 5 to 30 seconds depending on the size of the machine, preferably 5 seconds in fast cycling machine. Thus, the load on the joint between the toggle pin (109) and the die height platen (107) reaches maximum and releases load every 5 seconds. This creates friction between the toggle pin (109) and the die height platen (107) in every 5 seconds; thereby it is prone to wear and tear in the conventional technologies. To bear the maximum load and sustain the die height platens life bushings (108) are provided.
Said Bushings (108) are attached on the bore of the die height platen (107) without use of additional bushing; wherein the bushing (108) are placed between die height platen (107) and toggle pin (109). The bushings (108) are made of high strength bronze alloy which has very long mechanical life. With the bushings, all the load on the joint between the toggle pin (109) and the die height platen (107) gets transferred to the bushings (108); wherein the bushing (108) bears the load which was damaging the die height platen (107) in the conventional technologies. Said bushings (108) are periodically lubricated through auto lubrication system operated by the Controller (111).
The bronze bushings with self-lubrication eliminates possibility of oxidation process; thus, eliminates fretting corrosion and wear between die height platen toggle joint with toggle pin. Normally replacement of the bushings (108) is not necessary. In any case if bushings (108) wears out, one has to replace only the bushings (108) not the die height platen (107); eliminating the need of replacing the whole die height platen (107). Thereby the invention eliminates the possibility of fretting or corrosion; thus, it eliminates the breakdowns, which in turn extends the life of the machine; boosts the production output, reduces the maintenance cost and eliminates the extra material cost and manufacturing cost of the machine.
Working of the Invention
In said toggle clamping unit (100), during the clamp opening and clamp closing movement, the toggle linkages takes the load of the clamping force applied on the mold.
I. Clamp Closing movement
For injection molding in a injection molding machine, the toggle clamping unit (100) performs the clamp closing movement. During the starting of clamp closing movement, on receiving the command from said controller (111), the toggle clamping unit (1) is driven forward; wherein the moving platen (106), which has one half of the mold, is moved forward and clamps the mold mounted over the stationary platen (112) when it completes the clamp closing movement; building maximum clamping force. The load is maximum at the joints between the toggle linkages (102) when the toggle clamping unit (100) is closed as maximum clamping force is applied. The joint between toggle pin (109) and die height platen (107) takes this maximum load. The load reaches maximum and gets released in one clamping cycle. To bear this load bushings (108) are provided.
said Bushings (108) are attached on the bore of the die height platen (107) without use of additional bushing; wherein the bushing (108) are placed between die height platen (107) and toggle pin (109). The bushings (108) are made of high strength bronze alloy which has very long mechanical life. With the bushings, all the load on the joint between the toggle pin (109) and the die height platen (107) gets transferred to the bushings (108); wherein the bushing (108) bears the load which was damaging the die height platen (107) in the conventional technologies. Said bushings (108) are periodically lubricated through auto lubrication system operated by the Controller (111).
II. Clamp Opening Movement
After the molding is completed in the toggle clamping unit (100) the clamp force on the joints between the toggle linkages (102) is released through the toggle linkage Crosshead (101) and the toggle clamp unit completes the clamp opening movement. After the clamp opening movement, the mold half mounted on the Moving Platen (106) separates from the other mold half mounted over Stationary Platen (112).
Normally the clamp opening movement and clamp closing movement, that is the clamping cycle completes in 5 to 30 seconds depending on the size of the machine, preferably 5 seconds in fast cycling machine. Thus, the load on the joint between the toggle pin (109) and the die height platen (107) reaches maximum and releases load every 5 seconds. This creates friction between the toggle pin (109) and the die height platen (107) in every 5 seconds; thereby it is prone to wear and tear in the conventional technologies. To bear the maximum load and sustain the die height platens life bushings (108) are provided.
The bronze bushings with self-lubrication eliminates possibility of oxidation process; thus, eliminates fretting corrosion and wear between die height platen toggle joint with toggle pin. Normally replacement of the bushings (108) is not necessary. In any case if bushings (108) wears out, one has to replace only the bushings (108) not the die height platen (107); eliminating the need of replacing the whole die height platen (107). Thereby the invention eliminates the possibility of fretting or corrosion; thus, it eliminates the breakdowns, which in turn extends the life of the machine; boosts the production output, reduces the maintenance cost and eliminates the extra material cost and manufacturing cost of the machine.
Advantages of the invention:
• The present invention provides bushings placed to the bore of the die height platen, which is in between toggle pin and die height platen toggle pin hole.
• The present invention provides continuous lubrication in the bushes, which eliminates the possibility of fretting or corrosion.
• The present invention eliminates the need of extra bushings, hence eliminates the extra material cost and manufacturing cost.
• With the help of the present invention, only the bushings need to be replaced incase of wearing of parts instead of replacement of the die height platen as in the conventional machines.
• The present invention eliminates frequent possibilities of breakdowns.
• The present invention provides increased shelf life to the machine by eliminating the problem of fretting
• The present invention eliminates production loss by providing high strength bushings.
• The present invention reduces the maintenance cost of the machine by providing high strength bushings.
• The present invention provides a low-cost solution to overcome the problem of fretting in the die height platen.
,CLAIMS:We Claim:

1. An anti -fretting mold clamping unit in toggle injection molding machine that utilizes existing:
• A Toggle linkage crosshead (101);
• Plurality of Toggle Pins (109);
• Plurality of Strain Rods (110); and
• A Controller (111);
Characterized in that,
• Plurality of Toggle linkages (102);
• A Moving platen (106);
• A die height platen (107);
• A Stationary platen (112); and
• Plurality of Bushing (108)
Said toggle linkages (102) connects the die height platen (107) to the moving platen (106); wherein the toggle linkages (102) comprises of:
• Plurality of Ternary links (104)
• Plurality of Binary links (103)
• Plurality of Crosshead links (105)
Said Die height platen (107) is connected to the toggle linkage (102) such that the die height platen (107) is locked with ternary link (104) with a strain rod (110); wherein the die height platen (107) is used to tolerate the resistive force generated by the ternary links (104); There are such eight-ternary links (104) provided; said Toggle linkage Crosshead (101) is connected to the moving platen (106) through said binary links (103); said Binary Links (103) have Bushing (108) inside which creates bearing joint with Toggle Pins (109) connecting with Ternary Links (104); The other end of Binary Link (103) connecting with Moving Platen (106) has fixed connection with Toggle Pin (109);
Wherein the Binary links (103) aids the bushes (108) to be fixed on the die height platen (107) without any complex changes, not on the ternary links (104);
Said Bushings (108) are attached on the bore of the die height platen (107) without use of additional bushing; wherein the load on the joint between the toggle pin (109) and the die height platen (107) gets transferred to the bushings (108).

2. The mold clamping unit in toggle injection molding machine as claimed in claim 1, wherein the bushing (108) are placed between die height platen (107) and toggle pin (109); said bushings (108) are made of high strength bronze alloy.

Dated this 22nd Day of February 2020

Gopi Trivedi
IN/PA 993
Authorized Agent of Applicant
To,
The Controller of Patents,
The Patent Office
At Mumbai.