US3427760A

US3427760A - Rotary locator for crankshafts

Info

Publication number: US3427760A
Application number: US427019A
Authority: US
Inventors: William E Happel
Original assignee: Landis Tool Co
Current assignee: Landis Tool Co
Priority date: 1965-01-21
Filing date: 1965-01-21
Publication date: 1969-02-18
Anticipated expiration: 1986-02-18
Also published as: DE1577392C3; DE1577392B2; DE1577392A1; DE1937604U; GB1131521A

Description

Feb. 18, 1969 w. E. HAPPEL ROTARY LOCATOR FOR CRANKSHAFTS sheet Filed Jan. 21, 1965 TR] 6 CR3 INVENTOR WILLIAM E.H4PPEL ATTORNEY Sheet 2 of 2 Feb. 18, 1969 w. E. HAPPEL.

ROTARY LOCATOR FOR CRANKSHAFTS Filed Jan. 21, 1965- I Y will!!! illlllllll v m I: 1] ll I Tirlll {in H rill! L lllllllll'l Winn D If!!! g um l IIIII llllllll INVENTOR WI LLIAM E-HAPPEL BY ATTORNEY United States Patent 4 Claims ABSTRACT OF THE DISCLOSURE The apparatus of this application is a steady rest used primarily for supporting crankshaft journals during; a grinding operation. In addition to the'function of sup porting the crankpin journals during a grinding operation, the device also is used to provide a precision rotary location of a crankshaft prior to a grinding operation by effecting a firm contact between locating surfaces which locate each crankpin in axial alignment with the work drive axis. In order to perform this locating operation to best advantage, it has been found advisable to use means other than the members which hold the work engaging shoe against the work during a grinding operation. In this case, the work engaging shoe is mounted on the erid of a piston-type plunger which is held by means of a spring in engagement with a hydraulically operated actuating wedge. The wedge is moved endwise to urge the plunger and shoe into engagement with a crankpin during a grinding operation. A separate source of fluid under relatively low pressure is connected to act directly on the plunger, i.e., independently of the wedge, to urge a work engaging shoe against a crankpin for the rotary locating function. This is a decided improvement over previous devices for performing the same function, none of which involves applying a low pressure directly to the shoe supporting plunger.

This invention relates to grinding machines, particularly machines for grinding the crankpins of crankshafts, and more particularly, to the steady rest for supporting said crankpins during a grinding operation.

In an automatic crankpin grinder, the steady rest performs a dual function. After automatic rotary indexing of a crankshaft, the crank is given an additional turning action to be sure that the locating surfaces are in solid engagement. This function has been performed by advancing the back rest shoe by the same means which advances it during a grinding operation. It has been found that the force exerted by the shoe when actuated in this manner, tends to deflect the crankshaft beyond the point where the locating surfaces are in suitable engagement.

The term index as used here relates to the longitudinal and rotary movement of a crankshaft from the position for grinding one crankpin to a position for grinding the next crankpin, particularly where each crankpin is in a different plane or has a dilferent axis.

The term locate relates to a precision operation on a crankshaft after the above mentioned index operation has been completed. The locating function involves endwise movement of the crankshaft to effect precision alignment of the crankpin with the grinding wheel and a slight rotary movement to insure firm contact between the rotary locating surfaces on the crankshaft and the co acting locating elements on the face plate or work drive member.

It is, therefore, an object of the present invention to provide means for effecting precision angular location of a crankpin in such a manner as to avoid deflecting the crankshaft.

Another object is to :provide one means to advance a steady rest shoe for effecting precision angular location "Ice of a crankpin and another means for advancing said shoe for, a grinding operation.

Another object is to provide low pressure means for effecting precision angular location of a crankpin on a crankshaft.

FIG. 1 shows a hydraulic and electric circuit for successively actuating a steady rest member to effect precision angular location of a crankpin and, thereafter, to support said crankpin for a grinding operation.

FIG. 2 is a partial front elevation, partly in section, showing the relation between the locating pin and the locating hole or notch in the flange.

The invention consists of a frame 10 pivotally mounted at 11 on a base (not shown). Piston and cylinder 21 are suitably mounted to advance and retract frame 10 about its pivot toward and from crankpin W of crankshaft C.

The steady rest consists of an upper plunger member 25 slidable in frame 10 and having a shoe 26 for engaging crankpin W. A lower supporting member 30 is pivotally mounted at 31 on frame 10 for movement by an actuating means 32 to engage and support crankpin W from below against grinding wheel 15.

. The means for advancing and retracting plunger mem ber 25 and shoe 26 consists of a cam member 35 in abutting relation with stub rod 36 of piston 37 in cylinder 38. In order to retract plunger member 25, fluid under pressure must be supplied in the opposite direction to piston 40 having an abutment 41 which engages the other end of cam member 35,- shifting said "cam member upwardly and permitting retraction of shoe 26 and plunger member 25 by means of spring 27. Plunger member 25 may also be actuated by directing fluid under pressure into chamber 28 formed in cylinder 38 between

pistons

37 and 40. This fluid acts on plunger member 25 as a piston to advance shoe 26 to engage crankpin W after said crankpin has been indexed, but before it is clamped, to rotate crankpin W about the axis of the crankshaft so as to effect solid engagement between the internal surface of hole in crank flange 51 and locating pin 52 in index plate 55, which enters hole 50 when crank-pin W is placed in the machine. On some cranks, the flange is notched to provide a surface for engagement by pin 52.

Operation Frame 10 is advanced to horizontal operative position by piston 20. At this time, steady rest shoe 26 is not in contact with crankpin W.

Limit switch 4LS is closed when frame 10 places plunger member 25 in horizontal position, and comletes a circuit to energize control relay 4CR and timer relay TR.

Timer relay contact TR1 closes in the circuit to valve solenoid 3.

Control relay contact 4CR1 closes to energize control relay 6CR.

Control relay contacts 6CR1 and 6CR2 close a circuit through previously closed timer relay contact TR1 to energize valve solenoid 3.

Valve is shifted to the right against spring 61 to direct fluid under pressure from the pump through a pressure reducing valve 62 to chamber 28 to apply a relatively low pressure to cause plunger member 25 to engage and rotate crank-pin W about the axis of the crankshaft C to urge one side of hole 50 in crank flange 51 against locating pin 52.

The purpose of timer relay TR is to permit angular location to be completed before axial location takes place. When timer relay TR times out, timer relay contact TR1 opens, deenergizing control relay 6CR and valve solenoid 3. Valve 60 is shifted to the left by spring 61,

dropping the pressure on plunger member 25 which is then retracted by spring 27.

After a predetermined grinding operation, shoe 26 is advanced to support the crankpin for a grinding operation. In order to accomplish this, relay contacts 40CR1 and 40CR2 are actuated by a suitable size control relay (not shown) to complete a circuit to energize valve solenoid 12.

Valve 65 is shifted by valve solenoid 12 to the right against spring 66 to direct fluid under high pressure to the upper end of cylinder 38, urging piston 37 downwardly against cam member 35. Cam member 35 advances plunger member 25 to engage crankpin W with greater force than for angular locating of crankpin W, for a grinding operation.

At the end of a grinding operation, relay contacts 40CR1 and 40CR2 are opened, deenergizing solenoid 12 which is shifted to the left by spring 66 to direct fluid under pressure to the lower end of cylinder 38. Said fluid under pressure urges piston 40 and abutment 41 against cam member 35 to reset said cam member and permit spring 27 to retract plunger member 25 and shoe 26.

I claim:

1. A device for elfecting precision rotary location of a crankshaft in a crank grinding machine comprising (a) means for rotatably supporting a crankshaft for rotation about an axis coinciding with the axis of acrank-pin,

(b) co-acting locating surfaces on said crankshaft and said supporting means,

(c) a steady rest frame pivotally mounted for movement toward and from work supporting position,

(d) a plunger slidably mounted in said frame,

(e) a work rest shoe on one end of said plunger,

(f) positive means operable after said frame is in said work supporting position for advancing said plunger relative to said frame to support a workpiece during a grinding operation,

(g) and means for effecting firm contact between said co-acting surfaces comprising means operable independently of and prior to operation of said positive means and while said frame is in said work supporting position to advance said plunger relative to said frame for applying a turning force to said crankshaft less than the force applied by said positive means.

2. Apparatus of claim 1 in which the means for applying a turning force to said crankshaft is a supply of fiuid under pressure, connected to act directly against the other end of said plunger.

3. Apparatus of claim 2 in which a timer energized when said frame moves to work supporting position, times out to disconnect said fluid under pressure from said plunger.

4. Apparatus of claim 1 in which yielding means is provided for holding said plunger in retracted position.

References Cited UNITED STATES PATENTS 1,961,091 5/1934 Smith.

2,099,161 11/1937 Leeuw 5l238 X 2,638,719 5/1953 Balsiger 51-238 X 2,655,828 10/1953 Hazen.

3,118,258 1/1964 Price et a1. 51--238 X 3,233,368 2/1966 Price 51238 X 3,041,792 7/1962 LaFleur 51-237 X HAROLD D. WHITEHEAD, Primary Examiner.

US. Cl. X.R.